13th ICSGE PPR RO OC CE EE ED DI IN NG GS S OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING December 27-29, 2009 ORGANIZED BY Structural Engineering DepartmentFaculty of Engineering Ain Shams University CAIRO- EGYPT 2009 PREVIOUS COLLOQUIUMS

Theme Date MODERN TRENDS IN REINFORCEDCONCRETE DESIGN17-19 January, 19841 COST EFFICIENT BUIULDING SYSTEMS5-8 January, 19852 THE USE OF MICRO-COMPUTERS IN CIVILENGINEERING6-9 December, 19863 STRUCTURAL SAFETY12-14 April, 19884 STRUCTURAL ENGINEERING16-18 May, 19895 INTERNATIONAL COLLOQUIUM ON STRUCTURAL ENGINEERING 14-16April, 19926 SEVENTH INTERNATIONAL COLLOQUIUM ON STRUCTURAL AND GEOTECHNICAL ENGINEERING 17-19December, 19967 EIGHTH INTERNATIONAL COLLOQUIUM ON STRUCTURAL AND GEOTECHNICAL ENGINEERING 15-17 December, 19988 NINTH INTERNATIONAL COLLOQUIUM ON STRUCTURAL AND GEOTECHNICAL ENGINEERING 10-12 April, 20019 TENTH INTERNATIONAL COLLOQUIUM ON STRUCTURAL AND GEOTECHNICAL ENGINEERING 22-24 April, 200310 ELEVENTHINTERNATIONAL COLLOQUIUM ON STRUCTURAL AND GEOTECHNICAL ENGINEERING 17-19May, 200511 TWELFTHINTERNATIONAL COLLOQUIUM ON STRUCTURAL AND GEOTECHNICAL ENGINEERING 10-12 December,2007 12 Copyright@2009AINSHAMSUNIVERSITY,FACULTYOFENGINEERING, DEPARTMENT OF STRUCTURAL ENGINEERING, CAIRO, EGYPT. All papers were refereed and prepared by the authors accordingtotheguidelinesprovidedbythecolloquiumcommittees,andtheabstractshavebeen photographicallyreproducedfromtheoriginalcopies.Thecompletemanuscriptsofallpapersare available upon request on the official colloquium CD.Please contact the individual authors for permission to reprint or to use information from their papers. Printed in Cairo, Egypt December 2009 PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-1 December 27-29, 2009Preface This is the thirteenth conference to be organized by the Department of Structural EngineeringofAinShamsUniversitySince1984.Theprevioustenconferences focused on different themes of structural and geotechnical engineering. Itisbelievedthatthesecolloquiumshavebeenanexcellentopportunityfor engineers,consultantsandresearcherstodiscusrecentdevelopmentsindifferent fieldsofstructuralandgeotechnicalengineering.Theeleventhinternational colloquiumischaracterizedbydistinguishedinternationalandnationalkeynote speakerstodeliverspeciallecturesonselectedtopicsrelevanttotheirareasof expertise. . Atotalof103technicalpapersandthreekeynotelecturesareincludedinthe official conference CD and proceedings, which cover the following main topics: 1)Structural Analysis, 2)Steel Structures, 3)Concrete Structures, 4)Geotechnical Engineering, 5)Properties of Materials, 6)Construction Management, and 7)Composite Constructions. Alltechnicalpaperssubmittedtothisconferencewereevaluatedbyscientific refereesselectedfromdifferentEgyptianuniversitiesandresearchcenterswhohave doneanexcellentjobtoassurethehightechnicalcaliberofthechosenpapers.The keynotelectureswillbedeliveredover3plenarysessionsandthetechnicalpapers have been grouped in 24 parallel sessions through the 3-day conference. Wehavebeenfortunateinthisconferencetoattractresearchersfromalmostall Egyptianuniversitiesandresearchcenters,theArabworld(Syria,UnitedArab EmiratesandAlgeria),andtheinternationalcivilengineeringcommunity(USA, Canada, Germany and Malaysia) Iwishtoexpressmysincereappreciationtotheorganizingandeditorial committeesfortheirpatienceandtheremarkableeffortinrespondingtothemany demandsoftheconference.Iwishalsotothankallauthorsfortheirsignificant contribution and cooperation towards the success of the conference. Conference Chairman Prof. Dr.ABDELRAHIM KHALIL DESSOUKI December, 2009 PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-2 December 27-29, 2009 CHAIRMAN Prof. Dr. Abdelrahim Khalil Dessouki SECRETARY GENERAL Prof. Dr. Emam Soliman ADVISORY COMMITTEE Prof. Dr. Mohamed Mohamed El-Hashimy Prof. Dr. Adel Helmy Salem Prof. Dr. Abdel Hady Hosny Prof. Dr. Saafan Abdel Gawad Saafan Prof. Dr. Abdel Monem Moussa Prof. Dr. Kamal Hassan Prof. Dr. M. Nabil El Atrouzy Prof. Dr. Gamal Nassar Prof. Dr. Hamdy Abdel Azim Mohsen Prof. Dr. Hassan Osman Prof. Dr. Shaker El-Behairy Prof. Dr. Abdel Wahab Aboul Enain Prof. Dr. Said Y. Debaiky Prof. Dr. Ahmed Abdel Monem Korashy Prof. Dr. Farouk El-Kadi Prof. Dr. Samir Hassan Okba Prof. Dr. Mohamed Ibrahim Soliman Prof. Dr. Mostafa Kamel Zidan Prof. Dr. Hassan Ibrahim Hegab Prof. Dr. Mahmoud Ibrahim El-Banna Prof. Dr. MostafaKorashy Prof. Dr. Amin Saleh Ali Prof. Dr. Mona Moustafa Eid Prof. Dr. Fathalla Mohamed El-Nahhas Prof. Dr. Ezzat Abd El Fattah Emirah Prof. Dr. Omar El-Nawawy Prof. Dr. El Sayed Ibrahim El Sayed Prof. Dr. Abdalla Abou-Zid SCIENTIFIC COMMITTEE Prof. Dr. Abdelrahim Khalil Dessouki Prof. Dr. Mohamed A. Elaghoury Prof. Dr. Ibrahim Moharram Prof. Dr. Ali AbdelfattahProf. Dr. Ahmed Sherif Essway Prof. Dr. Emam Soliman Prof. Dr. Amr Ali Abdelrahman Prof. Dr. Ibrahim Abdelrasheed

ORGANIZING COMMITTEE Prof. Dr. Fathalla Mohamed El-Nahhas Prof. Dr. Abdelrahim Khalil Dessouki Prof. Dr. Emam Soliman Prof. Dr. Fathy Saad Dr. Fatma Shaker EDITORIAL COMMITTEE Prof. Dr. Emam Soliman Prof. Dr. Magda El-Rakabawy Prof. Dr. Fathy Saad Dr. Mohamed A. Abdel-Motaal Dr. Khalid Morsy Dr. Mohamed Farouk Dr. Ahmed Abdel Mageed CD DESIGN AND DATA BASE Dr. Said Youssef Abou El-Haggag THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING13th ICSGE - Cairo, 27 - 29 December 2009 Ain Shams University - Cairo, Egypt CONFERENCE COMMITTEESPROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-3 December 27-29, 2009 SCIENTIFIC REFEREES (Alphabetic Order) Prof. Dr.Abdel Hady Hosny (Ain Shams University)Prof. Dr.Abdel-Monem Moussa (Ain Shams University)Prof. Dr.Abdelaziz Mahmoud Ibrahim (Alexadria university)A. Prof. Dr.Abdelrahim Badawy (Ain Shams University) Prof. Dr.Abdelrahim Dessouki (Ain Shams University)A. Prof. Dr.Abdelwahab Elghandoor (Ain Shams University)Prof. Dr.Adel Abo El-Yazied El Samadony (Helwan University)A. Prof. Dr.Adel Fathi (Ain Shams University)Prof. Dr.Adel Helmy Salem (Ain Shams University)Prof. Dr.Ahmed Sherif Essawy (Ain Shams University)Prof. Dr.Ahmed Abdelrahman (National Research Center) Prof. Dr.Ahmed Abdelsalam (Ain Shams University) Prof. Dr.Ahmed Samieh (Helwan University) Prof. Dr.Ahmed Atef Rashed (Cairo University ) Prof. Dr.Ahmed Moussa (Helwan University)Prof. Dr.Ahmed Maged ElHousiny (Ain Shams University) A. Prof. Dr.Ahmed Hassan (Ain shams university)A. Prof. Dr.Ahmed Fathy Abdel-Aziz (Ain Shams University)Prof. Dr.Ahmed Kamal Abdel Khalik Soliman ( 6th October University) Prof. Dr.Ahmed Korashy (Ain Shams University)Prof. Dr.Ahmed Samer EzeldinProf. Dr.Ali Abdelfattah (Ain Shams University)Prof. Dr.Amira Mohamed Mohamed Abdelrahman (HBRC) Prof. Dr.Amr Abdelrahaman (Ain Shams University)Prof. Dr.Amr Darrag (Cairo University ) Prof. Dr.Amr S. Eldieb (Ain Shams University)A. Prof. Dr.Amr Helmy (Ain Shams University) Prof. Dr.Ashraf Biddah (UAE University)Prof. Dr.Ashraf El-Zanaty (Cairo University ) Prof. Dr.Ayman Abou Elfetouh (Ain Shams University)Prof. Dr.Ayman Hussein Khalil (Ain Shams University)Prof. Dr.Ehab ElsalakawyProf. Dr.ElSayed Abdelraaouf Nasr (Ain Shams University) Prof. Dr.Emad E. Elbeltagi (Mansoura University)Prof. Dr.Emam Soliman (Ain Shams University) Prof. Dr.Ezzeldien Yazeed (Ain Shams University) Prof. Dr.Ezzat Emirah (Ain Shams University) Prof. Dr.Farouk El-Kadi (Ain Shams University) Prof. Dr.Fathalla El-Nahhas (Ain Shams University) Prof. Dr.Fathy Abdrabbo (Alexandria University) Prof. Dr.Fathy Saad (Ain shmas University)A. Prof. Dr.Fatma Ahmed Shaker (Ain Shams University)Prof. Dr.Gamal Nassar (Ain Shams University) Prof. Dr.Gamil TadrosProf. Dr.Gouda Ghanem (Helwan University) Prof. Dr.Hamdy Mohsen (Ain Shams University)Prof. Dr.Hany El SawaProf. Dr.Hany El-Hashmy (Cairo University ) A. Prof. Dr.Hany El-Shafie (Ain Shams Uinversity)Prof. Dr.Hassan Osman (Ain Shams University)PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-4 December 27-29, 2009Prof. Dr.Hesham Sobhy (Cairo University )Prof. Dr.Hussain Abbas (Azhar University) Prof. Dr.Hussein Elmamlouk (Cairo University ) Prof. Dr.Ibrahim Abdelrasheed (Ain-Shams University) Prof. Dr.Ibrahim Shaaban (Zagazig University, Shoubra)Prof. Dr.Ibrahim Moharram(Ain Shams University) Prof. Dr.Ibrahim Mahfouz (Zagazig University, Shoubra) Prof. Dr.Ishac Ibrahim Ishac(Zagazig University)Prof. Dr.Kamal Hassan (Ain Shams University) Prof. Dr.Khaled Soudki A. Prof. Dr.Khaled Morsi (Ain Shams University) Prof. Dr.Khaled El-Zahaby (HBRC)Prof. Dr.M. El-Said Essa (Cairo University)Prof. Dr.Magda El-Rakabawy (Ain Shams University)Prof. Dr.Mahmoud Elbanna (Ain-Shams University) A. Prof. Dr.Mahmoud Ghorab (Ain Shams University) Prof. Dr.Mashour Ghoniem (Cairo University) Prof. Dr.Mazhar Mohamed Saleh (Cairo University)Prof. Dr.Metwaly Abohamd (Cairo University) A. Prof. Dr.Mohamed Salah (Banha University, Shoubra) A. Prof. Dr.Mohamed Abdel Moaty (Ain Shams University) Prof. Dr.Mohamed Mohamedain (Seuz Canal University)A. Prof. Dr.Mohamed Taha (Ain-Shams University) Prof. Dr.Mohamed El-Aghoury (Ain Shams University)Prof. Dr.Mohamed Nour Fayed (Ain Shams University) Prof. Dr.Mohamed AmmarProf. Dr.Mohamed Amer (Cairo University ) Prof. Dr.Mohamed NagibProf. Dr.Mohamed Dabaon (Tanta University).Prof. Dr.Moheeb El Saed (Cairo University)Prof. Dr.Mohssen Mashhour (Zagazig University) Prof. Dr.Mokhtar Seddeik (Cairo University ) A. Prof. Dr.Mona Mostafa (Ain Shams University)Prof. Dr.Mona Eid (Ain Shams University)Prof. Dr.Mostafa Mossaad (Cairo University ) Prof. Dr.Mostafa Zidan (Ain Shams University)Prof. Dr.Mustafa Korashy (Ain Shams University)Prof. Dr.Nabil GraceProf. Dr.Nabil Sayed Mahmoud (Mansoura University)Prof. Dr.Nabil Abdel Badeia Yehia(Cairo University )Prof. Dr.Nahla Hassan (Ain Shams University) Prof. Dr.Omar El-Nawawy (Ain Shams University)Prof. Dr.Osama MoselhyProf. Dr.Osama Elnesr (Ain Shams University)Prof. Dr.Osama Elhoseiny(Zagazig University) Prof. Dr.Osama Hosny (Helwan University) Prof. Dr.Osama Hamdy (Ain Shams University) Prof. Dr.Raafat El-Hacha (University of Calgary ) Prof. Dr.Refaat Abdl Razik (Zagazig University) Prof. Dr.Saafan Abdel Gawad Saafan (Ain Shams University) Prof. Dr. Said Hassanein (Azhar University) Prof. Dr.Sami Rizkalla Prof. Dr.Samir Okba (Ain Shams University) Prof. Dr.Samir Hekal (Ain Shams University) Prof. Dr.Sherif Hassan (Ain Shams University)A. Prof. Dr.Sherif Abdel-Basset Ibrahim (Ain Shams University) PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-5 December 27-29, 2009Prof. Dr.Sherif Ahmed Mourad (Cairo University)Prof. Dr.Tahia Abdel Monam(Ain Shams University) Prof. Dr.Tamer El Maaddawy (UAE University) Prof. Dr.Tarek ZaedProf. Dr.Yasser Elmosallamy (Ain Shams University) A. Prof. Dr.Yehia Abdel Zaher (Ain Shams University) PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-6 December 27-29, 2009

EGYPT13 thInternational Conference on Structural and Geotechnical Engineering December 27- 29, 2009 CAIRO EGYPT 2009 ORGANIZED BY Structural Engineering Department Faculty of Engineering Ain Shams University ACIEgypt Egyptian National Group Main Sponsors PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-7 December 27-29, 2009 TABLE OF CONTENTS SUBJECT Page GEOTECHNI CAL ENGI NEERI N 1 ENGI NEERI NG MANAGEMENT 180 REI NFORCED CONCRETE 271 STEEL STRUCTURES 604 THEORY OF STRUCTURES 855 STRENGTH OF MATERI ALS 994 COMPOSI TE MATERI ALS 1102 PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 A-8 December 27-29, 2009 GEOTECHNI CAL ENGI NEERI NG GEO- 001NUMERI CAL I NVESTI GATI ON OF SPATI AL PASSI VE EARTH PRESSURE Somar GHASSOUN,Khalid ABDEL- RAHMAN,and Mar t in ACHMUS GEO- 002I MPLI CATI ONS OF EARTHQUAKE AND STRUCTURAL PARAMETERS ON DAMAGE OF I NELASTI C STRUCTURES Abbas Moust afa GEO- 003TWO DI MENSI ONAL SI MULATI ON FOR THE EARTH RESSURE ofPoi ntLoad Act i ng Behi nd a Cant i l ev erWal lGeorge Maurice I skanderGEO- 004SEI SMI CI TY OF EGYPT AND NATI ONAL SEI SMI C NETWORK Abbas Moust afaGEO- 005DESI GN OPTI MI ZATI ON OF URBAN NATM TUNNELLI NG Most afa Zaki Abd Elrehim and Ahmed Mohamed MarwanGEO- 006ASSESSMENT OF VI BRATI ON HAZARDS DUE TO PI LE DRI VI NG Ali Abdel- Fat t ah Ali,Mohamed Ahmed Abdel- Mot aal,and Tamer Mohamed SorourGEO- 007CHARACTERI STI CS OF SHELLY SANDGihan Elsayed AbdelrahmanGEO- 008I MPACT OF UNDERGROUND PI PELI NES FAI LURE ON STRUCTURES Kamal Ghamer y Met wally,Manar Mohamed HUSSEI N,and Adel Yehia AklGEO- 009DAMAGE ASSESSMENT USI NG I NTEGRATI ON BETWEEN FEM AND GI S KAMAL GHAMERY METWALLY,MANAR MOHAMED HUSSEI N,and ADEL YEHI A AKLGEO- 010MODELI NG OF GROUNDWATER LOWERI NG I N A SEMI - CONFI NED AQUI FER AREAAhmed Mosalem Samieh and Asmaa Hanafy MahmoudGEO- 0113- D FI NI TE ELEMENTS ANALYSI S OF TUNNEL SYSTEM PERFORMANCE FROM APPLI CATI ON TO PRACTI CE Sh At rash,Sa Mazek,and Mk El GhamrawyGEO- 012RATE EFFECT ON PORE PRESSURE BEHAVI OUR UNDER COMPRESSI ON TRI AXI AL LOADI NGI hcene Lamr i,Must apha Hidj eb,Noureddine Chelghoum,and HarratKamelGEO- 013THREE- DI MENSI ONAL ANALYSI S OF THE DYNAMI C I NTERACTI ON EFFECTS BETWEEN TWO SURFACE FOUNDATI ONSAhmed BoumekikGEO- 014THE ROLE OF SMALL STRAI N CONSTI TUTI VE MODEL FOR PREDI CTI NG DI FFERENTI AL SETTLEMENT ABOVE TUNNELS Fat halla Mohamed El- Nahhas and Yasser Moghazy El- MossallamyGEO- 015SHAKEDOWN ANALYSI S OF ASPHALT PAVEMENTS UNDER MOVI NG WHEEL LOADS Most apha BoulbibaneGEO- 016PORE WATER PRESSURE ARI SI NG DURI NG PI LE DRI LLI NG I N SAND Fat hi Mohamed Abdrabbo and Khaled El- Sayed Gaaver PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERINGICSGE-13 December 27-29, 2009 13th ICSGE 27-29Dec.2009 Cairo - Egypt Ain Shams University Faculty of Engineering Department of Structural Engineering Thirteenth International Conference on Structural and Geotechnical Engineering NUMERICAL INVESTIGATION OF SPATIAL PASSIVE EARTH PRESSURE

Eng. SOMAR GHASSOUN Institute of Soil Mechanics, Foundation Engineering and Waterpower Eng.Leibniz University of Hannover, Appelstr. 9A, Hannover, GermanyE-mail: ghassoun@igbe.uni-hannover.de Dr. KHALID ABDEL-RAHMANInstitute of Soil Mechanics, Foundation Engineering and Waterpower Eng.Leibniz University of Hannover, Appelstr. 9A, Hannover, GermanyE-mail: khalid@igbe.uni-hannover.de Prof. MARTIN ACHMUS Head of Institute of Soil Mechanics, Foundation Engineering and Waterpower Eng.Leibniz University of Hannover, Appelstr. 9A, Hannover, GermanyE-mail: achmus@igbe.uni-hannover.de ABSTRACT: Inordertoinvestigatethespatialpassiveearthpressure,thisboundaryvalueproblem wasmodelledusingthefiniteelementmethod(FEM)withtheprogramABAQUS. Thesoilwasmodelledasasandysoil.Theconstitutivemodelusedisbasedonthe theory of hypoplasticity. This special material law simulates the non-linear stress-strain behaviour of the soil and takes implicitly the stress-dependence of the angle of internal friction into account.The interface between the rigid walls and soil was modelled using contactelements.Thecomputationsweredevelopedforthreedifferentmodesofthe wallmovement(parallelmovement,rotationaroundthetopofthewallandrotation around the toe of the wall).Thepassiveearthpressurecoefficientsfordifferentwalldimensions(breadth/height) were calculated. The results are compared with the analytic computation models based ontheGermancode,inordertobeabletoderivestatementsabouttheirqualityand range of their validity. GEO-001-1PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-1-ICSGE-13 December 27-29, 20091INTRODUCTION The calculation of passive earth pressures acting on underground structures is a central probleminsoilmechanics.Thehorizontalpressureactingonafixedrigidwallis termed the earth pressure at rest. The earth pressure decreases when the wall is moving away from the subsoil until a minimum value, which is called the active earth pressure. Onthecontrarytheearthpressureincreaseswhenthewallmovestowardsthesoil mediumuntilitreachesitsmaximumsoilresistancewhichiscalledpassiveearth pressure.ForawallwithheightHandabreadthBmuchlargerthanHthetwo-dimensional(planestrain)solutionoftheearthpressureproblemapplies,withthe passiveearthpressureforceinnon-cohesivesoilstobedeterminedbythefollowing equation: p2pk B H 21E =(l) with: :Unit weight of soil H, B:Height and breadth of the wall kp:Passive earth pressure coefficient The earth pressure coefficient in the two-dimensional case is dependent on the angle of internal friction of the soil and on the wall friction angle .AccordingtotheGermanregulationDIN4085,equation(1)isvalidforparallel movement of a wall. For other deformation modes, the resulting force is smaller. For a wall rotating around the top the reduction factor can be estimated to about 0.67 and for a rotation around the toe between 0.5 and 0.67 (DIN 4085).The problem of two dimensional passive pressure has been sufficiently investigated, in contrast to its three dimensional counterpart. The latter can be registered in special cases suchas:anchorblocks,anchorplatesandretainingwallswithlimitedbreadths. Moreover,the3-Dpassivepressureproblemaffectsthedesignoflaterallyloaded beams,piles,pilecapsandthesupportingwallsusedintunneling(orpipes)heading starting shaft.Thepassiveearthpressurecoefficientforthethree-dimensionalcaseislargerthanfor thetwo-dimensionalcase.AccordingtoanapproachinDIN4085basedon investigationsofWeienbach(1961),theincreaseisdependentonthespatialityratio B/H and on the angle of internal friction .Openquestionsregardingspatialpassiveearthpressureconcerntheexactvalueofthe earthpressurecoefficient,itsdependenceonthewalldeformationmodeandtheshape of load deformation curves. 2PREVIOUS INVESTIGATIONS OF SPATIAL PASSIVE EARTH PRESSURE Different experimental investigations were done firstly by Weienbach (1983) on model walls(I-beam)withandwithoutverticalwallmovementsembeddedinsand.He concluded that the spatial passive earth pressure is higher than the classical 2D passive GEO-001-2PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-2-ICSGE-13 December 27-29, 2009earthpressureanddevelopedanempiricalformulatocalculatethespatialearth pressure.Ovesen(1964)conductedanextensiveseriesofmodeltestsonanchorplates toinvestigatethe3-Deffects.Histestsshowedthatpassiveearthpressuresarehigher thanthosepredictedusingconventionalmethods.BrinchHansen(1966)developeda methodforcorrectingtheresultsofconventionalpassivepressuretheoriesbehind anchorplatestoaccountfor3Deffects.Hefoundalsothatthedimensionofthe supporting structure is an important factor for the analysis of 3D passive earth pressure. Neuberg (2002) made an experimental model of a retaining wall (I-profile) at University ofDresdeninordertocalculatethe3Dpassiveearthpressure.Basedonhisresults,a computationapproachforearthpressureatpeakandamobilizationequationwere developed. A number of investigators developed alternative theoretical approaches for determining spatialpassiveearthpressure.Blum(1932)developedafailuremechanism,asin Coulombs theory, by creating a three-dimensional flat failure surface. Based on the log spiral method, a spreadsheet was developed by Duncan and Mokwa (2001) to calculate thespatialpassiveearthpressure.Theyobtainedahyperbolicload-deflection relationship to estimate the spatial passive earth pressure. Soubra and Regenass (2000) developedamethodtocalculate3-Dpassiveearthpressurecoefficientsbasedonthe upper-bound method of limit analysis. The method consists of three phases considering different block mechanisms. Merifield and Solan (2006) published numerical modelling in order to calculate the capacity of anchors in frictional soils based on a certain failure mechanism.Stefan(2007)usedABAQUStoinvestigatethebehaviourofasolidpile wall and derived a mobilization curve for medium-dense sand. Benmebarek et al. (2007) performed a numerical study of 3D passive earth pressure by parallel movement of rigid wallsusingFLAC3D.Theirresultswerepresentedindesigntablesrelatingdifferent geometrical parameters and 3D passive earth pressure coefficients. 3 MATERIAL BEHAVIOUR Thenumericalmodellingwasdoneforsandysoil.Regardingthewell-reported experimentaldataaboutKarlsruhesand,thematerialparametersrequiredwere determinedforthissand.Karlsruhesandconsistsmainlyofsubroundquartzgrains. The index properties of the sand are given in Table 1. The behaviour of Karlsruhe sand intriaxialtestswasinvestigatedbyKolymbas&Wu(1990).Resultswithdense samples (e0 = 0.53) for different confining pressures (3) are shown in Figure 1. Table 1: Index properties of Karlsruhe medium sand Unit weight of the grains, kN/m326.5 D10, mm0.240 D60, mm0.443 Uniformity coefficient, Cu1.85 Min. void ratio, emin0.53 Max. void ratio, emax0.84 GEO-001-3PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-3-ICSGE-13 December 27-29, 2009Stress ratio 1 3/ Volumetric strain vAxial strain 1Axial strain 1 Fig. 1 Experimental triaxial test results for dense Karlsruhe sand(Kolymbas & Wu1990) Themodellingofthematerialbehaviourofthesoilisofcourseofcrucialimportance forthequalityofthecomputationresults.Thecomputationswereexecutedforeach movement mode using the hypoplastic material law developed for sandy soil.HypoplasticitywasfirstlydevelopedatuniversityofKarlsruheinthefollowingform (tensor equation): ( ) e D, T, h TJ=(2) with: TJ:Jaumanns' stress rate h: Tensor function T: Cauchy stress tensor D:symmetric part of the velocity gradient e: void ratio Theformulationforsandsisrateindependent,whichmeansthatthefunctionhis positivehomogeneousoffirstorderinD.Theconstitutiveequationallowsforthe application for large strain problems. The numerical modelling is based on the version developed by von Wolffersdorf (1997) in the following equation GEO-001-4PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-4-ICSGE-13 December 27-29, 2009( ) ( ) [ ] D T N f D T L f f T*d*e b J+ = ,(3)with tensor functions L and N. D is the euclidian norm of the symmetric part of the velocitygradient.Thefunctionsfeandfddescribetheinfluenceofdensityandfbthe influence of mean pressure. T* is the normalized cauchy stress tensor using the trace of T.Theconstitutiveequationhaseightconstants,whicharemeasuredinasimpleway fromstandardtestsinsoilmechanics.Theeightconstantsusedinthefiniteelement analysisarelistedintable(2).Foradetaileddiscussionaboutthemathematical backgroundandphysicalmeaningoftheinputparametersfortheconstitutivemodel refertoHerle(1997).FormoredetailsconcerningthismateriallawrefertoHerle& Gudehus (1999). Table 2: Input parameters for hypoplastic material law for Karlsruhe Sand. cgrain stiffness (hs) ed0ec0nei0 30.05800.0 MN/m20.53 0.84 0.25 1.00 0.131.05 4NUMERICAL MODEL Forthenumericalinvestigationwiththefiniteelementmethod(FEM),theprogram ABAQUS was used. The main aspects of the modelling are listed below: Due to symmetry, only the half of the model was discretized; Thedimensionsofthethree-dimensional model area were varied in order to fit differentwalldimensions(breadth/height).ForexampleforB=10.0mthe dimensionsofthemodelwassetto130.0m*100.0m*20.0m.Thegeometrical modelisshowninfigure2.Withthesemodeldimensionsthecalculated behaviour of the wall is not influenced by the boundary conditions; Thesoilwasmodelledwith8-nodedsolidelements(Figure3).Theinteraction behaviourintheboundarysurfacebetweenwallandsoilwasmodelledusing interfaceelements.Relativedisplacementsoccur,iftherelationshipbetween shearing and normal stresses exceeds a defined limited value (); In the front surface of the model area twelve different smooth rigid walls (W1 to W12)werespecified(s.Fig.2).Theearthpressureonthemovablewallwas calculated by integrating the horizontal soil stresses behind the wall. Regarding themodeofwallmovement,parallelmovement,rotationaroundthetoeofthe wallandrotationaroundthetopofthewallwereexamined.Theotherwalls remain unmoved during the modelling process; Geometrical non-linearity was also implemented; For the results reported in this paper, the coefficient of friction between the soil and the smooth rigid walls was set to zero (frictionless); The modelling process was made for three different initial void ratios (e0=0.55, 0.65, 0.75), i.e. three different relative densities, as shown in Table 3. The modelling process is executed stepwise. Firstly, the primary stress state using own weightofthesoilmediumisgeneratedfordifferentinitialvoidratios.Thefollowing table(Table3)showstherequiredparametersforthisstage.Thefrictionsanglewas GEO-001-5PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-5-ICSGE-13 December 27-29, 2009estimatedregardingtheinitialrelativedensity.Inthesecondsteptherequiredrigid walls were moved under three different basic wall movements as mentioned before. Table 3: Input parameters for primary stress state. eo void ratio no porosity D relative density () friction angle (/m3) unit weight Ko earth press.0.550.35592.0%38.517.10.46 0.650.39456.8%35.016.10.48 0.750.42826.0%30.515.10.50 Fig.2 Geometrical model used Fig. 3 Finite element mesh 5 NUMERICAL MODELLING RESULTS 5.1Effect of the relative Density (D) The first wall examined with the finite element method (FEM) exhibits a height (H) of 10.0mandawidth(B)of10.0m(B/H=1.0)forthreedifferentinitialvoidratios.A parallelmovementof1.30mto1.40mwasappliedtomobilizethepassiveearth pressure conditions. Figure 4 shows the relationship between the passive earth pressure coefficient (kph) and the normalised displacement (U/H) under parallel movement. GEO-001-6PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-6-ICSGE-13 December 27-29, 2009 Fig. 4 Passive earth pressure coefficient as a function of the normalized wall displacement for parallel translation Theearthpressurecoefficientatpeakrangesfrom8.0bydensesand(e0=0.55)till5.0 byloosesand(e0=0.75).AccordingtotheGermancode4085,theearthpressure coefficientcalculatedforplanestrainconditionsshouldbemultipliedbyacorrection factor (D) to calculate the spatial passive earth coefficient as follows ( ) ( )BH tan 0.6 1 DIN + =(4) The following table summarises the obtained results: Table 4: The earth pressure coefficient from the German Code 4085 and FE-results. initial void ratio friction angle () earth press. coeff. (kp2DDIN)earth press. coeff. (kp3Dfem)kp3Dfem/kp2DDIND0.7530.53.105.01.611.350.6535.03.706.01.621.420.5538.54.308.01.861.48 Fromtheprevioustable(Tab.4),thecorrectionfactorsobtainedfromFE-resultsare higherthanfromtheGermancode,whichmeansthattheGermancodeisonthesafe side. 5.2Effect of the wall deformation mode Inordertostudytheeffectofwalldeformationmode,anothermodelforamedium-dense sand (e0=0.65) with the same spatiality ratio (B/H=1.0) under three different wall movements was developed. In the case of rotation around the toe the limit value could not be reached so an approximate value was calculated for U/H equal to 15%. Theearthpressurecoefficientreachesitsmaximumvalue(6.0)byparallelmovement andtheminimumvalue(4.0)byrotationaroundthetoeofthewall(Fig.5).Whereby GEO-001-7PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-7-ICSGE-13 December 27-29, 2009the rotation around the top of the wall gives a passive earth pressure coefficient equal to 5.10.Thismeansthatthecoefficientbyrotationaroundthetopofthewallisalmost equalto0.85ofthecoefficientforparallelmovementandthecoefficientbyrotation around the toe is equal to 0.67 of the coefficient of parallel movement. Compared with the German code DIN 4085, it is found that ratios are larger, i.e. again the German code gives results lying on the safe side.

Fig. 5 Passive earth pressure coefficient as a function of the normalized wall displacement for medium-dense sand (e0=0.65) 5.3Effect of the spatiality ratio (B/H) Inthefollowing,thenumericalmodellingwasdoneforacertainwallheight(H)of 10.0m and the wall breadth (B) was varied from 10.0m till 50.0m. In the Figures 6 a) to c) the dependence of the passive earth pressure coefficient (kp) on the normalized wall displacement(U/H)isrepresentedforthethreedifferentwallmovementmodes.The kph-valuesresultingfromtheanalyticproceduresarelikewisepresented.Thesefigures show the following: 1.The limit value of the passive earth pressure depends on the wall breadth or on the spatiality ratio n = B/H for the three different wall movements. With a higherspatialityratio(n),thepassiveearthpressurecoefficient(kph) decreases until it reaches the standard 2D-passive earth pressure condition. 2.TheGermancodes(DIN4085)givesatpeakgenerallyaconservative passive earth pressure coefficient compared with the numerical results. 6.SUMMARY AND CONCLUSIONS FortheinvestigationspresentedaFEMmodelwasdevelopedtosimulatethespatial passiveearthpressureproblemsinsand.Thecomputationswereexecutedusingthe hypoplastic material model developed for granular materials e.g. sand. It is evident that fortheinvestigatedcase(smoothwall)theGermancodegivesveryreasonableresults comparedwiththenumericalmodellingresults.Thespatialpassiveearthpressure coefficientdependsmainlyonthewalldeformationmodeandontherelativedensity (D). Also the breadth to height ratio (B/H) affects the passive earth pressure. GEO-001-8PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-8-ICSGE-13 December 27-29, 2009 Fig. 6 (a): Passive earth pressure coefficient (kp) as a function of the normalized wall displacement (U/H) for parallel movement Fig. 6 (b): Passive earth pressure coefficient (kp) as a function of the normalized wall displacement (U/H) for rotation around the top of the wall Fig. 6 (c): Passive earth pressure coefficient (kp) as a function of the normalized wall displacement (U/H) for rotation around the toe of the wall The need for research regarding the spatial passive earth pressure problem is shown by thenumericalcalculations.Ononehand,themobilizationcurvesbetweenthe normalizedwalldisplacement(U/H)andthepassiveearthpressureshouldbederived GEO-001-9PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-9-ICSGE-13 December 27-29, 2009fordifferentwallmovementmodes.Ontheotherhand,earthpressuredistribution shouldbeinvestigated.Alsoaparametricstudyregardingdifferentsoil-wallfriction angle and different wall heights should be performed. REFERENCES: [1]ABAQUS (2008). User Manual, Version 6.8. [2]Blum,H.WirtschaftlicheDalbenformenundderenBerechnung,Bautechnik 10(5) 1932. [3]BrinchHansen.ComparisonofMethodsforstabilityAnalysisThree-dimensionalEffectinstabilityanalysisresistanceofarectangularanchorslab- Danish Geotechnical Institute Bulletin No.21, 1966. [4]DIN 4085. Berechnung des Erddrucks, Deutsches Institut fr Normung. Beuth Verlag, (2007). [5]Duncan,M.,Mokwa,R.PassiveEarthPressures-TheoriesandTests,ASCE journalofgeotechnicalandgeoenvironmentengineering,Vol.127,No.(3), 248-257, (2001). [6]Herle,I.,HypoplastizittundGranulometrievonKorngersten, VerffentlichungendesInstitutsfrBodenmechanikundFelsmechanikder Universit Karlsruhe, Germany, Heft 142, (1997). [7]Herle,I.,Gudehus,G.,Determinationofahypoplasticconstitutivemodelfrom propertiesofgrainassemblies.MechanicsofCohesive-frictionalMaterials,4: 461-486, (1999). [8]Kolymbas,D.andWu,W.Recentresultsoftriaxialtestswithgranular materials, Powder Technology, 60, 99-119, (1990). [9]Neuberg,C.EinVerfahrenzurBerechnungdesrumlichenErddruckesvor parallelverschobenenTrgern,VerffentlichungendesInstitutsfr Geotechnik, Technische Universitt Dresden, Heft 11,(2002). [10]Ovsen,NK.Anchorslabs,CalculationmethodsandModeltests,Danish Geotechnical Institute Bulletin, NO. 16, 5-39, 1964. [11]Soubra,A-H,Regenass,P.Three-dimensionalPassiveearthPressuresby KinematicalApproach,ASCEjournalofgeotechnicalandgeoenvironment engineering, Vol. 126, No. (11), 969-978 ,(2000). [12]Stefan,J.NichtlinearerHorizontalerBettungsmodulansatzfr TrgerbohlwndeinmitteldichtgelagertemSandVerffentlichungendes institutsfrBodenmechanikundGrundbau,TechnischeUniversitt Kaiserslautern (2007). [13]Weienbach,A.BeitragzurErmittlungdesErdwiderstands,Bauingenieur 58, 161-173,(1983). [14]VonWolffersdorf,P.A.VerformungsprognosenfrSttzkonstruktionen, VerffentlichungendesInstitutsfrBodenmechanikundFelsmechanikder Universitt Karlsruhe, Germany, Heft 141, (1997). GEO-001-10PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-10-ICSGE-13 December 27-29, 2009 13th ICSGE 27-29Dec.2009 Cairo - Egypt Ain Shams University Faculty of Engineering Department of Structural Engineering Thirteenth International Conference on Structural and Geotechnical Engineering IMPLICATIONS OF EARTHQUAKE AND STRUCTURAL PARAMETERS ON DAMAGE OF INELASTIC STRUCTURES ABBAS MOUSTAFADepartment of Civil Engineering, Faculty of Engineering, Minia UniversityMinia, P.O. Box 61111, Egypt E-mail: abbas.moustafa@yahoo.comIZURU TAKEWAKI Department of Urban and Environmental Engineering, Kyoto UniversityKyotodaigaku-katsura, Kyoto, P.O. Box 615-8540, Japan E-mail: takewaki@archi.kyoto-u.ac.jp ABSTRACT Thispaperinvestigatestheimplicationsoftheearthquakecharacteristics,suchas,the totalenergyandenergyconcentrationofthegroundmotionontheearthquakeinput energy,dissipatedenergiesanddamageofinelasticstructures.Influencesofthe structures parameters on the structural damage are also studied. The structural damage is quantified in terms of Park and Ang damage indices. Strong ground motions recorded inUSA,JapanandEgyptareemployedinthenumericalinvestigations.Thematerial force-deformationrelationismodelledusingelastic-plasticandbilinearlaws.The numerical analyses carried out in the Matlab platform reveal the significant effect of the earthquake parameters and the structural properties on damage of inelastic structures. KEYWORDS Stronggroundmotion,earthquakecharacteristics,inelasticstructures,elastic-plastic, input energy, hysteretic energy, damage indices, Egypt National Seismic Network. 1 INTRODUCTION Damageofstructuresduringearthquakesdependsonthestructuralproperties(natural frequencies,modeshapes,dampingmechanism,materialofconstructionandthe structural model) and also on the earthquake characteristics (source properties, epicentre distance, earthquake intensity, duration, Fourier amplitude and frequency content). The 12October1992DahshurearthquakethathittheGreaterCairoareaisaremarkable example on this aspect. Several buildings were severely damaged during this earthquake while other buildings experienced minor or no damage [1]. In earthquake engineering it is essential to model nonlinear structural behaviour, which in turn is encapsulated in the structural model adopted [2, 3]. When dealing with inelastic structures it is of interest to GEO-002-1PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-11-ICSGE-13 December 27-29, 2009investigatethestructuralresponseintermsofmodernmeasuresusingenergyconcepts anddamageindicesratherthanthestructuraldeformations[4-6].Thisisbecause structures get damaged due to not only maximum displacement excursion but also due to accumulated hysteretic energy dissipated by repeated yielding [7-9]. AccordingtotheEgyptianseismiccode,thenonlineartime-historyanalysisof structuresconstitutesthemostaccuratewayforpredictingthestructuralresponses understronggroundmotion[10].TheestablishmentoftheEgyptiannationalSeismic Network (ENSN) during 1993-1997, following the 1992 Dahshur earthquake, provided seismicdataonrecordedstronggroundmotionsforEgyptterritory.However,given thatadequateinformationonsoilconditionsbeneathrecordingstationsinEgyptisnot currently available, this paper examines implications of adopting alternative earthquake records, in terms of their characteristics, such as, energy and energy concentration, and alsothestructuralpropertiesonthestructuresdamage.Thenextsectiondemonstrates the dynamicanalysisofinelastic structures to earthquake loads. Section 3 explains the quantificationofthestructuralresponseusingenergyconcepts.Thedevelopmentof damage indices for inelastic structures under seismic loads is demonstrated in section 4. Section 5 provides numerical illustrations and discussions. 2 RESPONSE OF INELASTIC STRUCTURES TO EARTHQUAKE LOADS The equation of motion for an Nmulti-degree-of-freedom (MDOF) nonlinear structure driven by a single component of earthquake acceleration is given by [11]) (t xg& &) ( ) ( ) ( ) ( ) ( t x t t t tg s& && & &r M P F X C X M = = + +(1) where, M and C, are the mass and the damping matrices of the structure, respectively, isthevectorofhystereticrestoringforces,risavectorofones,X(t)isthe structure displacement vector and dot indicates differentiation with respect to time. Note that, for nonlinear damping models, the damping matrix C is a time dependent function. To proceed further, the incremental form of equation (1) can be written as ) (tsF)] ( ) ( }[ {1 k g k g st x t x & & & && & & = = + + +1 M P X K X C X M (2) ); ( ) (k 1 kt t X X X& & & & & & = +); ( ) (k 1 kt t X X X& & & = +) ( ) (k 1 kt t X X X = +(3) where Ks is the stiffness corresponding to the displacement from X(tk) to X(tk+1). Using Newmark- method, the velocity and displacement responses at time tk+1 are given as 2 2) ( ) ( )21( ) 1 (t t tt1 k k k k 1 k1 k k k 1 k + + + =+ + =+ ++ +X X X X XX X X X& & & & && & & & & & t (4) whereandaretheparametersoftheNewmark-methodandisthe time step. Equations (4) can be recast in an incremental form as k kt t t = +12121 21; 1 ) ( ) ( ) ( ) ( t t t t tk k k k k + ++ + = + = X X X X X X X& & & & & & & & & & (5) Substituting equations (5) into equation (2) we get P X X X K X X C X M = + + + + + + +] ) ( ) ( )21( [ ] ) 1 [(2121t t t t t k k k s k k& & & & & & & & & & & (6) GEO-002-2PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-12-ICSGE-13 December 27-29, 2009Substitutingin the above equation leads toX X X& & & & & & + =+ k k 1P X K X KX K X K X C X C X C X M = + + + + + + + & & & && & & & & & & & & & &s k sk s k s k kt t t t t t t 2 22) ( ) () )(21( ) 1 ( (7) Collecting similar terms and simplifying, it follows that P X K X K X C X K C M = + + + + +k s k s k st t t t t & & & & & & &2 2) (21] ) ( [ (8) Solving forwe getX& &] ) (21[ ] ) ( [2 1 2k s k s k st t t t t X K X K X C P K C M X& & & & & & & + + = (9) To represent the solution in a matrix form, equation (9) can be recast as s k s k st t t t t K C M B X K B C B X K B P B X2 1 2 1 1 1) ( ; ] ) (21[ ] [ + + = + = & & & & & (10) From equation (10), the acceleration is given as 1 + kX& &k s k sk s k s k k kt t tt t tX K B C B I X K B P BX K B C B X K B P B X X X X& & && & & & & & & & & & &] ) (21[ ] [] ) (21[ ] [1 2 1 1 11 2 1 1 11 + + = + + = + = (11) Substituting equations (11) into equations (5) and making use of equation (3), we get )]; ( ) ( [ ) ( ) ( or 1 1111k g k g k kkkkkkkt x t x t t & & & && &&& && + = +=+ ++++H q G q P HXXXGXXX(12) ;) (210) (21) ( ) ( 0) (21) ( ) (21) ( ) (1 2 1 11 3 1 2 1 21 4 1 3 2 1 3 = s ss ss st t tt t t tt t t t tK B C B I K BK B C B I K B IK B C B I K B I IG

(13) =M BM BM BH111 2) (t t NotethatthematricesKs,GandHaretimedependentfunctions.Intheabove formulation a viscous damping model is considered, and, thus the damping matrix C is constant.Hystereticnonlineardampingcanalsobeconsideredinwhichthedamping matrix is treated as a time dependent function (see Section 5). The stiffness used in the solution for time step tk+1 is taken as the secant stiffness from timesteptk-1totk.Tocorrectforthisapproximation,aniterativeprocedureforthe GEO-002-3PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-13-ICSGE-13 December 27-29, 2009stiffness Ks is performed where the initial stiffness is replaced by Ks(1) , Ks(2), , Ks(n) untilaconvergencecriteriononKsisachieved.Thenextsectiondemonstratestheuse of energy concepts in characterising the structural inelastic response. 3 INPUT AND DISSIPATED ENERGIES BY INELASTIC STRUCTURES Severalstudieshavecharacterizedthestructureresponseintermsofearthquakeinput energyandenergydissipatedbythestructure[4-6].Theseenergytermsarequantified by integrating the structure equation of motion as follows = + +t tgTtsT TtT d x d d d 0 0 0 0) ( } { ) ( ) ( ) ( ) ( ) ( ) ( ) ( & && & & & & & &1 M X F X X C X X M X (14) The right side of equation (14) represents the input energy to the structure since ground starts shaking until it comes to rest. The first energy term of the left side is the relative kinetic energy EK(t) of the masses associated with their motion relative to the ground == =Nii itTt x m d t E120K) (21) ( ) ( ) ( && & & X M X (15) The second term in equation (14) is the energy dissipated by damping ED(t) == =tNitDi iTd f x d t E010D) ( ) ( ) ( ) ( ) ( && &X C X(16) Forviscousdampingmodels,theaboveexpressionreducesto . The third term of equation (14) is the sum of the recoverable strain energy E= =NiNjtj i ij d x x c1 10) ( ) ( & &s(t) and the hysteretic cumulative plastic energy dissipated by yielding EH(t) ) ( ) ( ) ( ) (s10si Ht E d f x t ENiti == &(17) The recoverable strain and kinetic energies vanish by the end of the earthquake duration and the earthquake input energy to the structure is absorbed by damping and hysteretic mechanisms. The next section explains the use of maximum deformation and hysteretic energy in developing damage indices for inelastic structures. 4 DAMAGE MEASURES FOR INELASTIC STRUCTURES Theliteratureondamagemeasuresforstructuresunderearthquakegroundmotionsis vast,seee.g.,Refs.[12-14].Damageindicescanbebasedoneitherasingleor combinationofstructuralresponseparameters.Examplesofdamagemeasuresthatare based on a single response parameter are the ultimate ductility and number of yieldings during ground shaking [12,14]. Clearly, these measures do not incorporate information on how the earthquake input energy is imparted on the structure nor how this energy is dissipated.Earthquakedamageoccursduetonotonlythemaximumdeformationor ductility but is associated with hysteretic energy dissipated by the structure as well. The definitionofstructuraldamageintermsoftheductilityfactoristhereforeinadequate. The rate of the earthquake input energy to the structure has been used as a measure of the structural damage [15]. Damage indices can be estimated by comparing the response parametersdemandedbytheearthquakewiththestructuralcapacities.Ref.[14] GEO-002-4PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-14-ICSGE-13 December 27-29, 2009proposedadamageindexintermsoftheultimateductility(capacity)andthe maximum ductility attained during ground shaking (demand) umax11umaxy uy max==x xx xDI(18) Howeverdoesnotincludeeffectsfromhystereticenergydissipation.References [12,13] proposed a damage index based on the structure hysteretic energy DIHE1) /(uy y HH=x f EDI(19) wherearetheyieldforceanddisplacement.Arobustdamagemeasureshould includenotonlythemaximumresponsebutalsotheeffectofrepeatedcyclicloading. Park and Ang developed a simple damage index given as [7,16,17] y y, x fuy y Humaxu yHumaxPA) /(x f Ex fExxDI + = + = (20) Here,aremaximumabsolutedisplacementanddissipatedhystereticenergy under the earthquake. is the ultimate deformation capacity under monotonic loading andisapositiveconstantthatweightstheeffectofcyclicloadingonstructural damage. Note that if= 0, the contribution to DIH max, E xuxPA from cyclic loading is omitted. Thestateofthestructuredamageisdefinedas:(a)repairabledamage( ), (b)damagedbeyondrepair( ),and(c)totalcollapse( ). ThesecriteriaarebasedoncalibrationofDI40 . 0PA < DI0 . 1 40 . 0PA < DI 0 . 1PA DIPAagainstexperimentalresultsandfield observationsduringearthquakes[17].Equation(20)revealsthatbothmaximum ductilityandhystereticenergydissipationcontributetothestructuredamageduring ground motions. Herein damage is expressed as a linear combination of damage caused byexcessivedeformationandthatcontributedbyrepeatedcyclicloadingeffect.The quantitiesdependontheloadinghistorywhilethequantitiesH max, E xy u, , f x are independent of the loading history and are determined from experimental tests. Equation(20)canbeusedforastructuralmemberorasingle-degree-of-freedom structure.ForMDOFstructures,theglobaldamageindexisexpressedasaweighted sum of members local damage indices N i E E DI DINii i iNii i,..., 2 , 1 ; / ;1 1G= = = = = (21) Hereinistheenergyabsorbedbytheithmember.InthispaperweadoptParkand Angdamageindicesinquantifyingthestructuraldamage.Thenextsectionprovides numerical illustrations and discussions on the formulation developed in this paper. iE5 NUMERICAL ILLUSTRATIONS AND DISCUSSIONS 5.1Elastic-plastic single-storey frame building GEO-002-5PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-15-ICSGE-13 December 27-29, 20090 10 20 30 40-1-0.500.511940 El Centro 0 10 20 30 40-1-0.500.511966 Parkfield 0 10 20 30 40-1-0.500.510 10 20 30 40-1-0.500.512001 Egypt1995 Kobe Fig. 1: Earthquake records adopted as design inputs to inelastic structures Time [s]Time [s] Time [s]Time [s] Acceleration / g Acceleration / g Acceleration / g Acceleration / g Table 1: Earthquake records used as inputs to inelastic structures EarthquakeM Dss (km) Component td (s)Station siteRemarks 1940 El Centro 1966 Parkfield 1995 Kobe 2001 Egypt 7.0 6.1 6.9 6.2 12.99 31.04 13.12 30.00 EW C02065 TAK000 N 40.00 43.69 40.9645.00 ELC#9 Chol#2 Takatori Ariesh quarry USA USA Japan Egypt M = Richters magnitude, Dss = Source-site distance, td = earthquake duration. This example examines the earthquake input energy, dissipated energy by the structure anddamagestateofasingle-storeyinelasticframestructuretotheearthquakerecords showninFig.1.InformationontheserecordsisprovidedinTable1.Theserecords includerecordedgroundmotionsinUSA,JapanandEgypt.NotethatParkfieldand Kobe records have narrow frequency contents compared to El Centro and Egypt records as confirmed by the Fourier amplitude spectra. This could be attributed to source, path and local soil site effects. All records are normalized to 0.51 g peak ground acceleration. TheAriasintensitymeasure(squarerootofareaundersquareofgroundacceleration) for these records was computed as 28.24, 12.77, 37.74 and 17.21 m/s1.5, respectively.Thematerialnonlinearityismodelledusingelastic-plasticforce-deformationrelation. Theframesupportsatotalmassof9103kgandtheinitialstiffnessofthecolumns 3.5510 =0k5N/m.Theinitialnaturalfrequencyofthestructurewascomputedas =n 1.0Hz.Aviscousdampingmodelwith0.05dampingratioisadopted.Theyield GEO-002-6PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-16-ICSGE-13 December 27-29, 2009strengthofcolumnsintensionandcompressionaretakenas2104and-2104N, respectively. The dynamic analysis is performed following the formulation of Section 2. Figure 2 depicts the input and dissipated energies by the structure from the four records. Themaximumductilityfactoriscomputedas3.50,2.45,8.89and0.28forElCentro, Parkfield, Kobe and Egypt records, respectively. Thus, Egypt record does not drive the structureintotheinelasticrangealthoughtheAriasintensityishigherthanthatfor Parkfieldrecord.Infact,Egyptrecordhasitsenergylocatedatthehighfrequency range.Whenischangedsuchthat 0k =n 2.0Hz, max iscomputedas4.45,13.23, 16.56and1.03,respectively.Thispointstowardstheeffectofenergyconcentrationof ParkfieldandKobeaccelerationscomparedtoElCentroandEgyptrecords[18,19]. The total energy alone does not significantly affect the structural maximum ductility. Fig. 2: Response of inelastic single-storey structure to earthquake ground motion (a) Earthquake input energy (b) Hysteretic dissipated energy 0 10 20 30 40 500246810x 104 1940 El Centro1966 Parkfield1995 Kobe2001 Egypt(a) Time [s] EI N m 0 10 20 30 4001234x 104 1940 El Centro1966 Parkfield1995 Kobe2001 EgyptEH N m (b) Time [s] Table 2: Damage index for the single-storey frame building ( 0 , 15 . 0u= . 8 = ) Initial natural frequency of the structure Earthquake 0.501.002.004.00 1940 El Centro 1966 Parkfield 1995 Kobe 2001 Egypt 0.17 (RD) 0.21 (RD) 0.59 (DBR) -*0.55 (DBR)0.39 (RD) >1.0 (TC) -*> 1.0 (TC) > 1.0 (TC) > 1.0 (TC) 0.13 (RD) > 1.0 (TC) > 1.0 (TC) > 1.0 (TC) 0.90 (TC) * Linear behaviour, RD = repairable damage, DBR = damaged beyond repair, TC = total collapse. The damage state of the structure is determined using Eq. (20) with0 . 8 , 15 . 0 = =u (see Table 2). The effect of the structure initial natural frequency, the frequency content and concentration of acceleration energy on DIPA is obvious from the numerical values of Park and Ang damage index shown in Table 2. 5.2Bilinear inelastic two-storey frame building Thetwo-storeybuildingframeshowninFig.3isconsideredunderthesamesetof earthquakerecordsofTable1.ThisstructurewasstudiedbyMoustafa[20]for modellingcriticaldesignearthquakeloadsoninelasticstructures.Thebehaviourof braces 1 and 2 is taken as bilinear (k1= k0,= strain hardening ratio). The mass and initial stiffness matrices of the structure are given as GEO-002-7PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-17-ICSGE-13 December 27-29, 2009 += =222112 1cos ;0E ALE ALE Am K M2222220LE ALE ALmel(22) Thefloorsmassesaretakenas 52 110 75 . 1 = = m m kg,thecross-sectionalareasof bracesare 42 110 45 . 6 = = A A m2,theYoungsmodulus 1110 59 . 2 = E N/m2,and thestrainhardeningratio(ratioof topre-yieldstiffness)=0.10. Whenbothelastically,thestiffnessma ,ifbrace1 yields 1K K =s, if brace 2 yields 2K K =s and if both braces yield 12K K =s, where post-yieldstiffnessbracesarebehaving trix el sK K == = += +==LAELAE1 1) 1 ( cos11 2 cos2 2 LAE LAEelel2cos ;) 1 ( cos;1;1212221K K KK K (23) The first two natural frequencies of the elastic structure are computed as18 . 61 = rad/s and18 . 162 = rad/s.ARayleighproportionaldampingwitha= irsttwomosb a K M C + =0.2683, b = 0.0027 is adopted. These values are selected such that the damping ratio in thef desis0.05.Lettheyieldstrainofbraces y002 . 0 = forbothtension andcompression.Bracesyieldatarelativedisplacement04 . 0 cos / = = y yL x m. Brace1yieldswhen04 . 0 | |1 = x mandbrace2yieldswh 04 . 0 |1 = m.The parameters of the Newmark- method are taken as; 2 / 1 = = . Fig.4showstheearthquakeinputenergyandenergydissip ng.Itis observedthatKoberecordproducesthehighesti ilet inpen|2 x xand atedbyyieldinputenergywh helowestut 6 / 1 004 . 0 = t senergy is produced by Egypt record. The global damage index computed using equation (21)was0.41,0.38,0.69,and0forElCentro,Parkfield,KobeandEgyptrecords, respectively.Theeffectofthestrain-hardeningratio anddampingratio onthe earthquake input and dissipated energies were studied and are shown in Fig. 5. It is seen thattheglobaldamageindexreducesforhighervaluesof and .Theinfluenceof theearthquakeenergyconcentrationisseentobehigherthantheeffectofthestrain-hardeningratio.Similarly,thedampingratiosignificantlyinfluencestheearthquake E, A2E, A1Brace Brace 9.14 m9.14 9.14 mm2m1x2x1) (t xg& & ) (t xg& &Fig. 3: Two-storey frame building GEO-002-8PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-18-ICSGE-13 December 27-29, 2009input energy compared to the strain-hardening ratio (see Fig. 5). Tab3 summarizes the global damage index for alternative values of lewhich confirms these results. Fig. 4: Input energy and energy dissipated by the two-storey inelastic structure (a) Input energy (b) Hysteretic energy Table 3: Global damage index for the two-storey frame building ( 0 . 8 , 15 . 0 = =u ) Strain-hardening ratio ( ) Earthquake 00.050.100.20 1940 El Centro0.44 (DBR)0.41 (DBR)0.41 (DBR) 1966 Parkfield0.39(RD) 0.75 (DBR)0.68 (DBR) 0.39 (RD) 0.36 (RD) 0.66 (DBR)1995 Kobe 2001 Egypt-*0.38 (RD)0.38 (RD) 0.69 (DBR) -*-*-** Li r,pse. 6CORETh he structuralpropertiesonthedamageofinelasticstructures.Thestructuraldamageis ngdamageindices.Earthquakeaccelerograms near behaviour, RD = repairable damage g , DBR = dama e i d beyond repa TC = total collaNCLUDING MAR SKispaperinvestigatedtheimplicationsoftheearthquakecharacteristicsandtquantifiedintermsofParkandArecordedinUSA,JapanandEgyptareadoptedasseismicinputstotheinelastic structures considered. The material force-deformation relation is modelled using elastic-0 10 20 30 4005101520 1940 El Centro1966 Parkfield1995 Kobe2001 EgyptTime [s] EI kN m (a) 0 10 20 30 400510152025 1940 El Centro1966 Parkfield1995 Kobe2001 EgyptEH kN m Time [s] (b) Fig. 5: Influence of structure properties on earthquake input energy for the two-storey inelastic structure (a) Strain-hardening ratio (b) Damping ratio 0 10 20 30 4005101520 = 0.20 = 0.10 = 0.05 = 0EI kN m Time [s] (a)(b) 200 10 20 30 400510 15 = 0.01 = 0.03EH kN m (b) = 0.05 = 0.10Time [s] GEO-002-9PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-19-ICSGE-13 December 27-29, 2009plastic and bilinear laws. It is shown that the concentration of acceleration energy close tothefundamentalfrequencyofthelinearstructurehasasubstantialeffecton producing large structural damage. Other parameters such as the acceleration energy do notsignificantlyaffectthestructuraldamagecomparedtoenergyconcentration.The dampingratioisalsoseentosubstantiallyreducethedamageindexcomparedtothe strain-hardening ratio which has smaller effect on the structural damage. REFERENCES [1] Sadek, A.W. Earthquake Engineering & Structural Dynamics 26 (1997) 529-540. al of Faculty of Engineering, Tokyo university 36(2) (1981) 407-441. E 09) [2] Otani, S. Journ[3]Takeda,T.,Sozen,M.A.andNielsen,N.JournalofStructuralDivision,ASC96(ST12) (1970) 2557-2573. [4]Zahrah,T.F.andHall,W.J.JournalofStructuralEngineering,ASCE110(1984) 1757-1772. [5]Uang,C.M.andBereto,V.V.EarthquakeEngineering&StructuralDynamics19 (1990) 77-90. [6] Takewaki, I. Journal of Structural Engineering, ASCE 130 (2004) 1289-1297. [7] Park, Y.J. and Ang, A.H-S. Journal of Structural Engineering, ASCE 111(4) (1985) 722-739. [8] Moustafa, A. Journal of Structural Engineering, ASCE (2009) in press. [9]Decanini,L.D.andMollaioli,F.SoilDynamicsandEarthquakeEngineering21 (2001) 113-137. [10]PermanentCommitteeforCode-201.TheEgyptiancodeforcalculationofloads and forces on structural works and buildings, Cairo (2008). [11] Hart, G.C. and Wong, K., Structural dynamics for structural engineers, John Wiley & Sons, NY (2000). [12] Cosenza, C., Manfredi, G. and Ramasco, R. Earthquake Engineering & Structural Dynamics 22 (1993) 855-868. [13]Ghobara,A.,Abou-Elfath,H.andBiddah,A.EarthquakeEngineering& Structural Dynamics 28 (1999) 79-104. [14]Powell,G.H.andAllahabadi,R.EarthquakeEngineering&StructuralDynamics 16 (1988) 719-734. [15] Takewaki, I. Journal of Engineering Mechanics, ASCE 132 (2006) 990-1000.[16] Park, Y.J., Ang, A.H-S. and Wen, Y.K. Journal of Structural Engineering, ASCE 111(4) (1985) 740-757. [17] Park, Y.J., Ang, A.H-S. and Wen, Y.K. Earthquake Spectra, 3(1) (1987) 1-26. [18] Moustafa, A. Soil Dynamics and Earthquake Engineering, 29 (2009) 1181-1183. [19] Cao, H. and Friswell, M.I. Soil Dynamics and Earthquake Engineering, 29 (20292299. [20] Moustafa, A. Journal of Sound and Vibration, 325 (2009) 532-544. GEO-002-10PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-20-ICSGE-13 December 27-29, 2009 13th ICSGE 27-29Dec.2009 Cairo - Egypt Ain Shams University Faculty of Engineering Department of Structural Engineering Thirteenth International Conference on Structural and Geotechnical Engineering TWO DIMENSIONAL SIMULATION FOR THE EARTH RESSURE of Point Load Acting Behind a Cantilever Wall G. M. ISKANDER Department of Structural Engineering, Ain Shams University El-Sarayat Street, Abbassia, Cairo, P.O. Box 11517, Egypt E-mail: gmiskander@yahoo.com ABSTRACT The problem of earth pressure due to point load acting behind a cantilever wall is a three dimensionalone.Thelateralearthpressurevariesintheverticalandthetransverse directions. In this research, the equations of earth pressure due to point load described in theEgyptianCodeofPracticeareintegratedandsubmittedtoanalyticalprocedure throughwhichanequivalenttwodimensionalequationsaredeveloped.Anew parameterknownasthedesignwidth,whichisthehorizontaldistanceretainedbythe individual vertical retaining element is introduced. The used procedure and the resulted equations are tested and verified, by adopting different cases of the design width values covering the practical range. The resulted equations can be easily used together with the equationsofthelineloaddescribedintheEgyptianCodeofPracticefortwo dimensional analysis of the point load.KEYWORDS Earth pressure, retaining wall, cantilever wall, point load, and line load. 1INTRODUCTION Theretainingstructuresareusedtoavoidthecollapseoftheretainedsoil,andto support the adjacent structures. The reliable prediction of the effect of external loads on the retaining structure is very important step to achieve a safe and economic design. The supportingwallshouldbedesignedtolimitgroundmovement,Chandrasekaranand Hong [1].There are a number of methods to estimate the effect of external loads on the adjacent retainingwall.TheelasticitysolutiondevelopedbyBoussinesqhasbeencommonly adopted to estimate the earth pressure due to external loads. Many of the external loads canberepresentedbypointandlineloads.Researchersinvestigatedthelateralearth pressure on a retaining wall due to point and line loads; Kim and Barker [2], Greco [3], Wang [4], Greco [5], Wang [6], Wang [7], and El-Attar [8]. GEO-003-1PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-21-ICSGE-13 December 27-29, 2009Analytical closed form solutions have the great advantage of providing easy, direct, and powerful tool for the design process. The Egyptian Code of Practice [9] provides semi-empirical solutions for the cases of point and line loads. In this research, a new attempt hasbeenperformedanddiscussedtoachieveaneasieranalyticalprocedurefor analyzing the problem of a point load, by adopting the Egyptian Code equations. 2ANALYSISOFEXTERNALLOADSACCORDINGTOTHEEGYPTIAN CODETheEgyptianCodeofPracticeadoptsthesemi-empiricalexpressionsdevelopedfrom experimentalworkbyTerzaghi[10],toestimatetheearthpressureduetoexternal loads. 2.1 Case of Point Load Considerapointloadonthesurfaceofthegroundatdistance(x)fromacantilever unyielding rigid wall as shown in Fig. (1). For a free height of wall (H), the lateral earth pressure distribution on the wall due to point load (Q) in the vertical and the transverse directions is shown in Fig. (1-a) and Fig. (1-b), respectively. a- Vertical direction b- Transverse direction Fig. 1: Lateral earth pressure distribution on the wall due to point load Theinducedearthpressure( onthewallforapointatdepth(z)locatedalongthe vertical line just in front of the point load, is given by NAVFAC [11] as follows:form > 0.4 (1) form 0.4(2) Where; (3) GEO-003-2PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-22-ICSGE-13 December 27-29, 2009 (4) The corresponding earth pressure (for any other point at the same depth, located at horizontaldistance(y)apartfromtheloadlocation,alongthewallinthetransverse direction, is given by U.S. Army Corps of Engineers [12], as follows: (5)Where; (is the horizontal angle as shown in Fig. (1-b), and can be calculated from the formula: (6) Consequently: (7) 2.2Case of Line Load Consideracaseoflineload(q)onthesurfaceofthegroundatdistance(x)froma cantilever unyielding rigid wall as shown in Fig. (2). Fig. 2: Lateral earth pressure distribution on the wall due to line load For a free height of wall (H), the induced earth pressure (on the wall for a point at depth (z) is given by NAVFAC [11] as follows: form > 0.4(8) form 0.4 (9) Where; (m) and (n) are as previously given by equations (3) and (4), respectively. 3PROPOSED ANALYTICAL TECHNIQUE The analysis of a cantilever wall in the vertical direction is a plane strain problem. For the case of an adjacent point load, the induced earth pressure is usually approximated to a certain plane strain distribution in order to be included in the analysis. This process is generallyinaccurateone,whichmayleadtouneconomicorunsafedesignedsections. GEO-003-3PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-23-ICSGE-13 December 27-29, 2009Gourvenec et al. [13] highlighted the potential significance of three dimensional effects in the case of a retaining wall. Uncertainties in the geotechnical design variables have a significant impact on the safety of cantilever retaining walls as stated by Goh et al. [14]. Therefore,itisagreatneedtoconsiderproperlythethreedimensionaleffectofthe point load when analyzing the wall in the vertical direction. 3.1Design Width It would be a practically oriented step to define a parameter known as the design width (2D), which is the horizontal distance retained by the individual supporting element. In casethesupportingelementsarenotcompletelyworkingtogetherlaterally,thedesign width is the width retained by single pile for tangent or secant piles, and width retained by single panel for case of diaphragm wall, as shown in Fig. (3). For vertical elements completely working together laterally, this width could be chosen a considerable design valueinthelateraldirectionorcanbeevaluatedbasedonpracticalexperience considering the construction circumstances. Fig. 3: Lateral earth pressure distribution along the design width due to point load Theplanestrainanalysisofthewallshouldbecarriedoutconsideringtheadditional earthpressureduetothepointload.Themostimportantcasetobeconsideredisthe case of the design width is totally centered with respect to the load location as shown in Fig.(3),whichwillresultinthehighestadditionalstressduetopointload. Consequently,itisimportanttoevaluatetheaverageearthpressuredistributioninthe lateraldirectionthroughoutthisdesignwidth.Theaveragepressurevaluecannotbe directly obtained, but it should be evaluated through an integration procedure. 3.2Integration Procedure Itisnowrequiredtoevaluatethehorizontalstressarea(2A)boundedbythecurve within the design width as shown in Fig. (4-a).An infinitesimal portion of this area (dA) of width (dy), shown in Fig. (4-b) is calculated as follows: (10) GEO-003-4PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-24-ICSGE-13 December 27-29, 2009By substitution from equation (7), we get: (11) a-Area (2A)b- Portion of area (dA) Fig. 4: Area of stress in front of the design width due to point load Duetothesymmetryofthecurve,wecancalculatehalfofthisarea(A)forhalfthe design width (D) from the following integral: (12) Using equation (11), the integral form becomes: (13) Theexactclosedformsolutionofthisintegralisnotavailable.However,averyclose solution can be obtained through the following formula: (14) By substituting with the integral limits to evaluate its value, we finally get: (15) Andthisrepresentshalfthesymmetrichorizontalstressareaboundedbythecurve withinthedesignwidth.Thevalueoftheangle( )shouldbeinradians. Before using this final result, it is important to check the validity of this formula. 4TECHNIQUE VERIFICATION Before applying the developed formula, it should be carefully checked, to achieve safe design for the wall and provide sufficient stability for the ground and the neighbouring buildings. The induced ground movement affects the building damage risk-assessment, Aye et al. [15], and the building serviceability assessment, Hsiao et al. [16]. GEO-003-5PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-25-ICSGE-13 December 27-29, 2009Themethodofevaluatingtheaccuracyoftheformulaobtainedinequation(15),is basedoncalculatingthearea(A)byanothermethodandcomparingtheresults.The other method will be the numerical integration; by dividing this area into large number (100) of small rectangles each having area of (dA), and summing up the areas of these rectanglestocalculatethearea(A).Thewidthofeachrectangle(dy)willbe(D/100). ThistestingprocedureisbeencarriedoutthroughpreparinganExcelsheet.Two proposed examples are presented and each has two different cases. 4.1First Numerical ExampleThedataforthisexampleare:Q=1000kN,x=2m,H=5m,andz=1m.Therefore usingequations(3)and(4),wegetm=0.4andn=0.2,respectively.Sincem=0.4, thenweshalluseequation(2);thereforeh=56.0kN/m2.Thisexampleissolvedfor two cases. In the first case; D = 0.5m. By substitution in equation (15), we get A = 27.44kN/m. By evaluating this area numerically after dividing it into 100 slices as described above, we get A = 27.31kN/m. The percentage of difference between both methods is 0.5%. In the second case; D = 2.0m. By substitution in equation (15), we get A = 87.96kN/m. By evaluating this area numerically after dividing it into 100 slices as described above, we get A = 83.40kN/m. The percentage of difference between both methods is 5.5%. 4.2Second Numerical ExampleThe data for this example are: Q = 2000kN, x = 3m, H = 6m, and z = 1.5m. Therefore usingequations(3)and(4),weget m = 0.5 and n = 0.25, respectively. Since m = 0.5, thenweshalluseequation(1);thereforeh=50.35kN/m2.Thisexampleissolvedfor two cases. In the first case; D = 1.0m. By substitution in equation (15), we get A = 48.60kN/m. By evaluating this area numerically after dividing it into 100 slices as described above, we get A = 48.21kN/m. The percentage of difference between both methods is 0.8%. In the second case; D = 3.0m. By substitution in equation (15), we get A = 118.63kN/m. By evaluating this area numerically after dividing it into 100 slices as described above, we get A = 112.48kN/m. The percentage of difference between both methods is 5.5%.4.3 Technique Overview Twodifferentnumericalexamplesusingpracticalvaluesforthedifferentparameters, andeachhastwodifferentcasesofthedesignwidthvaluescoveringtherangeofthe practicallimits,areadoptedastestingtoolsforthevalidityandapplicabilityofthe developed formula in equation (15). The results indicate that the difference between the developed formula and the numerical integration is less than 1.0% for values of design width (2D) of about 1.0 to 2.0m, and is less than 6.0% for values of design width (2D) of about 4.0 to 6.0m. All the obtained differences are in the direction of the developed formula;theresultsofthedevelopedformulaaregreaterthanthoseofthenumerical integration,andthisisinthesafesideandgivesmoreconfidencefortheresulted design. GEO-003-6PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-26-ICSGE-13 December 27-29, 2009We can conclude that the developed formula in equation (15) can be practically applied toobtainaplanestraindistributionfortheearthpressureduetopointloadwithinthe distance of the design width.5TWO DIMENSIONAL SIMULATION OF POINT LOAD From the Egyptian Code equations, it is clear that the earth pressure due to a point load is a three dimensional distribution, whereas the earth pressure due to a line load is a two dimensionalone.Practically,engineersprefersimpleunsophisticatedtoolsin calculating straining actions for design, considering both economic and safety purposes. Therefore,thefinalobjectiveofthisresearchistodevelopatwodimensional simulationoftheearthpressureduetoapointload,bymakinguseofthepreviously developed and verified technique.5.1Average Stress Applying equation (15), thus, the average earth pressure throughout the design width is: (16) By substituting with the value of (from equations (1) and (2) into equation (16), we obtain equations (17) and (18), respectively: form > 0.4 (17) form 0.4(18) 5.2Equivalent Line Load Theaverageearthpressureduetoapointloadthroughoutthedesignwidthevaluated usingequations(17)and(18),canbesimultaneouslyobtainedfromacorresponding lineloadofacertainvalue.Tocalculatetheequivalentcorrespondinglineload,the obtained average stress in equations (17) and (18) should be equal to the earth pressure due to line load in equations (8) and (9), respectively. Therefore, form > 0.4, by equating equations (8) and (17), we get: (19) Consequently, the equivalent line load value is: (20) Form 0.4, by equating equations (9) and (18), we get: (21) And, the equivalent line load value is: (22) It should be clear that the values of line load, which provides earth pressure equivalent tothatresultedfromapointload,obtainedinequations(20)and(22)arevalidfora GEO-003-7PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-27-ICSGE-13 December 27-29, 2009certaindepth.Fordifferentdepths,thevalueof(n)varies,andconsequently,the resultedvalueof( )differs.Therefore,theearthpressuredistributionalongthewall height,equivalenttoapointload,willbeobtainedusingdifferentresultedvaluesof ( ). Nevertheless, this obtaineddistribution has the privilege of being calculated once andcanbesafelyusedasaplanestraindistributionwithinthespecifieddesignwidth (2D). 6CONCLUSIONS In this research, the semi-empirical expressions of earth pressure due to point load and lineload,describedintheEgyptianCodeofPracticearereviewed.Anewparameter knownasthedesignwidth(2D),whichisthehorizontaldistanceretainedbythe individualverticalretainingelementisintroduced.Thecaseofthedesignwidthis totallycenteredwithrespecttothepointloadlocationwhichresultsinthehighest additional stress due to point load, is considered and subjected to analytical procedure, throughwhichanintegratedformulaisdevelopedtoevaluatehalfthesymmetric horizontalstressarea(A)boundedbythecurveofthetransverseearthpressure distribution within the design width. Twodifferentnumericalexampleseachhastwodifferentcasesofthedesignwidth valuescoveringtherangeofthepracticallimits,aretestedandcomparedwiththe numerical integration results as a corresponding technique. The results indicate that the differencebetweenthedevelopedformulaandthenumericalintegrationislessthan 1.0%to6.0%,andthedifferenceisusuallyinthesafesidefordesign.Thedeveloped formulabecomesvalidandcanbeappliedpracticallytoobtainaplanestrain distribution for the earth pressure due to point load within the distance of design width.Thedevelopedformulaisusedtocalculatetheequivalentcorrespondinglineload formula.Theresultedequationscanbeeasilyusedtogetherwiththeequationsofline loaddescribedintheCodeofPractice for providing a two dimensional analysis of the point load. REFERENCES [1]Chandrasekaran, B., and Hong, L.P. Performance of a temporary earth retaining walldesignedtolimitgroundmovement,InternationalSymposiumon Underground Excavation and Tunnelling, Bangkok, Thailand (2006) 405-412. [2]Kim, J.S., and Barker, R.M. Effect of live load surcharge on retaining walls and Abutments,GeotechnicalandGeoenvironmentalEngineering,ASCE128(10) (2002) 803-813. [3]Greco,V.R.Activeearththrustbybackfillssubjecttoalinesurcharge, Canadian Geotechnical Journal 42 (5) (2005) 1255-1263.[4]Wang,C.D.Lateralstresscausedbyhorizontalandverticalsurchargestrip loadsonacross-anisotropicbackfill,InternationalJournalforNumericaland Analytical Methods in Geomechanics 29 (14) (2005) 1341-1361. [5]Greco,V.R.Activethrustduetobackfillsubjecttolinesofsurcharge, GeotechnicalandGeoenvironmentalEngineering,ASCE132(2)(2006)269-271. GEO-003-8PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-28-ICSGE-13 December 27-29, 2009[6]Wang,C.D.Lateralforceinducedbyrectangularsurchargeloadsonacross-anisotropicbackfill,GeotechnicalandGeoenvironmentalEngineering,ASCE 133 (10) (2007) 1259-1276. [7]Wang,C.D.Lateralforceandcentroidlocationcausedbyhorizontaland verticalsurchargestriploadsonacross-anisotropicbackfill,International Journal for Numerical and Analytical Methods in Geomechanics, 31 (13) (2007) 1443-1475. [8]El-Attar,A.N.Theeffectofexternalloadontheexcavationsupportingsystem, M.Sc. Thesis, Ain Shams University, Cairo, Egypt (2009). [9]Egyptian Code of Practice for Soil Mechanics and Foundations, Part 7 (2001). [10]Basedonworkby Terzaghi,K.Anchoredbulkheads,Transaction,ASCE119 (1954) Paper No. 2720. (Quoted from NAVFAC [11]). [11]NAVFAC. Foundations & Earth Structures, Design Manual 7.02, United States Department of Navy, Naval Facilities Engineering Command (1986). [12]U.S.ArmyCorpsofEngineers.Engineeringanddesignretainingandflood walls,ManualEMNo.1110-2-2502,U.S.Army,Washington,D.C.(1989). (Quoted from Kim and Barker [2]). [13]Gourvenec,S.M.,Powrie,W.,andDeMoor,E.K.Three-dimensionaleffectsin theconstructionoflongretainingwall,GeotechnicalEngineeringJournal, Institution of Civil Engineers 155 (3) (2002) 163-173. [14]Goh,A.T.C.,Phoon,K.K.,andKulhawy,F.H.Reliabilityanalysisofpartial safetyfactordesignmethodforcantileverretainingwallsingranularsoils, GeotechnicalandGeoenvironmentalEngineering,ASCE135(5)(2009)616-622. [15]Aye, Z.Z., Karki, D., and Schulz, C. Ground movement prediction and building damagerisk-assessmentforthedeepexcavationsandtunnelingworksin Bangkoksubsoil,InternationalSymposiumonUndergroundExcavationand Tunnelling, Bangkok, Thailand (2006) 281-297. [16]Hsiao, E.C.L., Schuster, M., Juang, C.H., and Kung, G.T.C. Reliability analysis andupdatingofexcavation-inducedgroundsettlementforbuilding serviceabilityassessment,GeotechnicalandGeoenvironmentalEngineering, ASCE 134 (10) (2008) 1448-1458. GEO-003-9PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-29-ICSGE-13 December 27-29, 2009 13th ICSGE 27-29Dec.2009 Cairo - Egypt Ain Shams University Faculty of Engineering Department of Structural Engineering Thirteenth International Conference on Structural and Geotechnical Engineering SEISMICITY OF EGYPT AND NATIONAL SEISMIC NETWORK ABBAS MOUSTAFADepartment of Civil Engineering, Minia University, Minia 61111, EgyptE-mail: abbas.moustafa@yahoo.com ABSTRACT DespitethemoderateseismicityofEgypt,manystructuresintheGreaterCairoareahavebeen severely damaged during the 12th October 1992 Dahshur earthquake. This is because most buildings werenotdesignedtowithstandseismicloadsbefore1992.Followingthisearthquake,theEgyptian GovernmentestablishedtheEgyptianNationalSeismicNetwork(ENSN).Thisnetworkconsistsof the main center at Helwan and five sub-centers at Hurghada, Burg El-Arab, Mersa Alam, Aswan and Kharga. The ENSN contains 70 recording stations, 25 of which represent strong-motion instruments. This paper provides overviews on the seismic activity of Egypt from an engineering perspective, and onthedevelopmentoftheENSN.Thepapersummarizesalsoinformationonhistoricalandrecent earthquakes hit Egypt. Ninety strong-motion records from 14 earthquakes measured by the ENSN are analyzed.Thepaperemphasizestheneedforupgradingexistingstrong-motioninstrumentsto measurethethreeaccelerationcomponentsandforinstallingnewstrong-motioninstrumentsin seismicallyactiveregions.Giventheaccumulationofstrong-motionearthquakesrecordedbythe ENSN over more than one decade, it is essential to construct strong-motion database for the country. This will facilitate performing seismological applications (locating hypocenters of future earthquakes, studyingsourcemechanismsandattenuationanalyses)andengineeringapplications(constructing design response spectra, providing acceleration inputs for time-history analysis of inelastic structures and safety assessment of lifeline structures, critical facilities and historical monuments). KEYWORDS Egypt seismicity, ENSN, NRIAG, seismic codes, Aswan high dam, historical monuments. 1INTRODUCTION Egypt seismicity is known for a long period of time and some of the historical earthquakes hit thecountryaredocumentedintheannalsofancientEgyptianhistory[1-3].Similarly, destructivestrong-motionearthquakeshitthecountryin1981,1987andmorerecentlyin 1992 [2,3]. Egypt seismicity results from the interaction between the three plates of Eurasia, AfricanandArabianplates,aswellastheSinaimicro-platethatispartiallyseparatedfrom the African plate by rifting along the Gulf of Suez. Thestructuraldamageandlossoflifecausedbythe1992Dahshurearthquake(35kmof southwest Cairo and magnitude = 5.6) in the Greater Cairo area have been reported in [4,5]. This earthquake resulted in 561 deaths, about 10,000 injuries and structural damage of about GEO-004-1PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-30-ICSGE-13 December 27-29, 2009$35million.Ref.[4]presentsinformationontheearthquakecharacteristics(location,focal depth, magnitude, and fault mechanism) of the main shock. Field surveys of the damaged and collapsedstructuressuchasbridgesandbuildingshavebeenalsocarriedout[4].Insightful anddetailedstatisticalanalysisofdamagecausedbythisearthquakeiscontainedin[5].A sample of 2270 buildings covering a wide geographical distribution, date of construction and structuralsystempropertieshasbeenconsidered.Thespecificpercentagesofdamage reported provide insight as to the seismic performance of different structures in terms of day ofconstruction,constructionmaterialandtypeofstructuralsystem[5].Followingthis earthquake,theEgyptianGovernmentestablishedtheEgyptianNationalSeismicNetwork (ENSN)during1993-1997.Thisnetworkhasbeenunderacontinuousupgradingwithnew seismicinstrumentsduringthelastfewyears.Meanwhile,actualseismicprovisionsagainst earthquakeloadshavenotexistedbefore1992.Nowadays,recentversionsoftheEgyptian standards contain seismic provisions against earthquake and wind loads. This paper provides overviews on seismic activity of Egypt from an engineering perspective, the development of the ENSN and on the evolution of national seismic provisions in Egypt. Ninetystrong-motionaccelerogramsrecordedbytheENSNarealsoanalyzed.Thepaper sheds the lights on the need for establishing strong-motion database for the country (detailed informationonstrong-motionearthquakesandknowledgeonsoilprofilebeneathrecording stations). The next section provides an overview on the seismicity of Egypt. 2SEISMICITY OF EGYPT Egypt has moderate seismicity and is known for its seismicity for a long time. In fact, some of the large historical events are documented in the annals of ancient Egyptian history and in temples [1-3]. Fig. 1 shows the location of historical earthquakes struck Egypt between 2200 BC and 1900 AD. The largest earthquake has a magnitude of 6.7 on the Richters scale. EgyptislocatedclosetoHellenicarc,oneofthecontinentalfracturesystematthe convergenceboundaryoftwobiglithosphericplates,namely,EurasiaandAfrica.The countryisalsoaffectedbytheopeningoftheRedSea(MidOceanicSystem)anditstwo branches, the Gulf of Suez and the Gulf of Aqaba-Dead Sea transform system [2,6,7]. Thus, Egypt seismicity results from the interaction between the three plates of Eurasia, African and Arabian plates, as well as the Sinai micro-plate which is partially separated from the African platebyriftingalongtheGulfofSuez.Inadditiontotheseismicactivityalongtheseplate margins,mega-shearzonesrunningfromsouthernTurkeytoEgypthavebeendefinedin somestudies[8,9].Historicalandinstrumentalseismicityintheregionismainlyassociated with six tectonic trends, namely, the Levant-Aqaba transform system, the northern Red Sea-Gulf of Suez-Cairo-Alexandria trend (Suez trend), the Eastern Mediterranean-Cairo-Fayoum trend,HellenicandCyprianarcs,Mediterraneancoastaldislocation,andthesouthern Egyptiantrends.IntensivehistoricreviewsontheseismicityofEgypt,ArabiaandtheRed Searegioncanbefoundin[2,3].Thetotalnumberofhistoricalearthquakesuntil1900is reported to be 83 [3]. Some of these earthquakes were initiated from seismic sources outside Egypt. The lack in number of earthquakes in some eras is attributed to the political situations and disappearanceofdocuments[3]. The period of observations has been grouped into four intervals,namely,2200BC-1300AD,1300-1800(startswiththebeginningofMamluk period), 1800-1990 (starts with the end of Ottoman Empire), and 1900-2004. The number of reported events was 34, 36, 17 and 54, respectively (i.e. 1, 6, 17 and 51 per century). Fig. 1 shows the map of local seismicity from 1900-1997 (before the installation of ENSN) [3]. The number of observed events has remarkably increased after 1997. GEO-004-2PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-31-ICSGE-13 December 27-29, 2009In 7 August 1847 a large earthquake with an estimated magnitude of about 5.5-5.9 shook El Faiyum-Cairo region. Hundreds of people were killed and injured and thousands of structures were destroyed. The earthquake was felt across Egypt and much of North Africa with heavy damage reported as far as Assuit, southeast Egypt. Fig. 1: Location of historical earthquakes in Egypt (2200 BC-1900 AD) [6] The surprise occurrence of a moderate earthquake of magnitude 5.3 in 14 November 1981, at Naserlakeabout55kmsouth-westofAswandam,generatedsignificantconcerninEgypt regardingsafetyofthedam.NotethatanydamagetoAswandamwouldcausecatastrophic consequencesontheEgyptiancommunity.Acomprehensivestudytoidentifyareasof seismicgeology,engineeringandotherworkstoevaluatetheseismicsafetyofthedamhas beenconductedin[10].ThestudyconcludedthatAswanregionislocatedinatectonically stable area, and that future earthquakes would not affect the integrity and safety of the dam. Similar concerns were recently raised again and the same conclusion was also reached by the NRIAG center [11]. The local seismic activity during the last few years, however, reflects a remarkable increase in number of small earthquakes. Note that the large number of recorded events could be attributed to the increase in recording stations of the ENSN. The installation ofnewseismicstationsatremotesiteshasgivengoodazimuthcoverageoverregionsthat were not covered before. In 23 August 1987 an event of magnitude = 3.5 and epicenter near Gabal Maghara north Sinai, far from faults related to the Gulfs of Suez and Aqaba, but along El Faiyum-North Sinai fold belt. The present seismic activity and well-documented evidence of historical earthquakes in the region, together with the exploration for economic petroleum GEO-004-3PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-32-ICSGE-13 December 27-29, 2009depositsintheQarunoilfieldledtounderstandingofthestructuralgeologyofElFaiyum depression[8].Ingeneral,theregionalseismicactivityofEgyptduringthelastfewyears shows a cluster of the seismic activity to the southern part of Hellenic and Cyprean arcs. The seismicactivityextendstowardnorthtothesouthernpartofGreeceandTurkey.AFew events were located along Southern Jordan, Northern Sudan and Central Red Sea. Fig. 2: Distribution of earthquakes hit Egypt during the period 1900-1997 The 1992 Dahshur earthquake of magnitude 5.6 has caused severe damage to many structures intheGreaterCairoarea.Whilethisearthquakerepresentsamoderateevent,thelarge damagecausedisattributedtononexistenceofactualcodeprovisionsforbuildingsagainst earthquakes[12].Mostexistingbuildingsbeforethisearthquakewerenotdesignedagainst seismicloads.Thedamagereportedisalsoattributedtooldageandpoorconstructionof somestructuresandtothedensepopulationintheGreaterCairoarea(about18million inhabitants). Cairo is one of most densely populated cities in the world. Thus, the occurrence of a moderate earthquake in that area could cause large damage and significant loss of life. 3DEVELOPMENT OF THE EGYPTIAN NATIONAL SEISMIC NETWORK InstrumentalrecordingofearthquakesinEgyptstartedin1899withtheestablishmentof HelwanObservatory[3,7].AMilne-Shawseismograph(east-westcomponent)wasinitially installed. An east-west component of a Milne-Shaw and a vertical component of a Galitzin-Willipwereaddedin1922and1938,respectively.Modernizedshort-periodSprengnether GEO-004-4PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-33-ICSGE-13 December 27-29, 2009seismographswereinstalledin1951.In1962aseismicstationwasinstalledatHelwan Observatory as part of the Worldwide Standardized Seismograph Network (WSSN). In 1972 four analog stations (one Japanese short-period and three intermediate Russian seismographs) wereinstalledatHelwan,Aswan,Abu-SymbilandMatrouh.Followingthe14November 1981 Naser Lake earthquake, a radio-telemetry network of eight seismographs was installed around the northern part of Aswan reservoir. The network was extended to eleven stations in 1984 and to thirteen stations in 1985. Six analog strong-motion accelerographs were installed atAswandam(about700kmsouthofCairo).Fourshort-periodverticalcomponents seismographswereaddedduring1986-1990atKottamia(KOT),Hurghada(HUR),TellEl-Amarna (TAS), and Mersa Alam (MRS) [7]. Table 1: List of recording stations of the ENSN connected to the main-center at Helwan [6] Location Station code Lat.Long. Height (m) Connection modeComponents (sensor type) HLW KOT FYM HAG FYD ZNM KHB MYD NAT AYT SAF GLL SQR BNS ZAF SUZ RSH RDS GRB TR1 TR2 EDF NKL CAT BST DHB NUB SFG QSR ADB SHL AGS DK2 SWA1 SWA2 29.858 29.927 29.692 29.952 30.293 29.375 29.928 29.275 29.633 29.704 29.622 29.577 29.881 28.952 29.282 29.840 30.960 28.711 28.270 28.007 28.385 25.102 29.929 28.775 29.216 28.722 29.027 26.568 25.755 25.351 23.107 24.375 24.320 29.263 29.243 31.343 31.829 31.043 32.093 32.231 32.877 30.972 30.799 30.617 31.153 31.555 31.708 31.196 31.212 32.550 32.830 33.722 33.297 32.786 33.952 33.723 33.181 33.980 33.979 34.732 34.618 33.648 33.929 34.387 34.623 35.399 34.987 28.955 25.709 25.455 115 495 204 480 200 41 265 250 570 160 460 515 115 207 155 275 217 260 175 280 275 410 440 410 200 30 145 460 166 206 147 326 410 50 55 Radio to HLWC Radio to HLWC Radio to HLWC Radio to HLWC Telephone to HLWC Satellite to HLWC Radio to HLWC Radio to HLWC Radio to HLWC Radio to HLWC Radio to HLWC Radio to HLWC Radio to HLWC Telephone to HLWC Radio to ZNM Radio to ZNM Telephone to HLWC Radio to ZNM Radio to ZNM Radio to ZET Radio to ZET Telephone to HLWC Satellite to HLWC Satellite to HLWC Satellite to HLWC Radio to BST Radio to BST Satellite to HLWC Satellite to HLWC Satellite to HLWC Satellite to HLWC Satellite to HLWC Satellite to HLWC Satellite to HLWC Radio to SWA1 3/3 Components (SP/LP) 3 Component (VBB) 3 Component (SP) 3 Component (SP) 3 Component (SP) 3 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 3 Component (VBB) 1 Component (SP) 3 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 1 Component (SP) 3 Component (SP) 3 Component (VBB) 1 Component (SP) Until1992,manypartsofthecountrywerenotcoveredwithearthquakerecording instruments. Except of the six instruments installed at Aswan high dam, there was no strong-motion instruments in the Greater Cairo area. Following the 12th October 1992 earthquake in Dahshurarea,theEgyptianGovernmentwaspromptedtoconstructtheEgyptianNational Seismic Network (ENSN). The network was completed in 1997 and included 63 instruments GEO-004-5PROCEEDINGS OF THE THIRTEENTH INTERNATIONAL CONFERENCE ON STRUCTURAL AND GEOTECHNICAL ENGINEERING-34-ICSGE-13 December 27-29, 2009coveringtheEgyptianterritory.Theseinstrumentscontain47seismicstationsbasedon satellite communication, 11 stations based on telemetry communication and 5 stations based ontelephonelines.Thenetworkrecordslocalandregionalearthquakesaswellastele-seismicevents.Thedatacommunicationsystemwasalsoupgradedfromtelephonelinesto satellite to increase the efficiency of the network. By the end of 2002, the installation of the wholeseismicfieldstationswascompletedcoveringthemaincenterandfivesub-centers werealsoconstructedandequipped.TheENSNconsistsofthemaincenteratHelwanand fivesub-centersatHurghada,BurgEl-Arab,MersaAlam,AswanandKharga.An Earthquake Disaster Reduction Data Center (EDRDC) was also established and supported by GIS technology. In 2003, the number of recording stations was upgraded to 70 stations. Table 1providesinformationonrecordingstationsconnectedtothemaincenter.Thiscenter receives seismic data from near distance stations through telemetry communication and from remote stations and sub-centers via telephone lines and satellite communications. Although,theENSNcontains