studying the effect of geometry and type of soil on the...

Studying the Effect of Geometry and Type of Soil on the

Stability of Clover -Leaf Cofferdam

Dr. Raad Hoobi Irzooki, and Marwa Kaddori Majeed

Abstract- The stability of glover leaf coffer dam in two soil cases

(dry and wet) and two positions (neutral and longitudinal), with nonlinear finite element analysis has been used in this study to predict the load deflection behavior of cellular cell cofferdam under lateral load. Series of laboratory tests have been carried out on one

(single) glover-leaf cofferdam cells of different width to height ratio (b/H) (0.75, 0.85, 1.0) with three types of soil fill (sand passing sieve No.4, river sand, subbase).

In finite element analysis, AN SYS(version 12.1) computer program with combination of CivilFEM was used, eight-node solid element SOLID 45 has been used to model filling with river sand

soil and the same element for steel sheet pile and foundation, by using glue technique to model of steel sheet pile of cofferdam, the load applied on the one third of the cell cofferdam height and full Newton-Raphson method is used for the nonlinear solution algorithm and the results are compared with experimental data.

The results expressed that the cells fill with wet subbase were more stable against sliding and overturning at different (b/H) ratio

and the cells that put on the longitudinal direction was more stable against sliding and overturning at different (b/H) ratio than the cells with neutral direction. Also, the results obtained using the finite element models show a good agreement with the experimental data. The difference between the numerical ultimate loads and the corresponding experimental ultimate loads is in the range between (0-6.9)%.

Index Terms— ANN, ANSYS, Glover-leaf cofferdam, Stability.

I. INTRODUCTION

Cellular cofferdams are constructed of steel sheet piling

and used primarily as water-retaining structures. They depend

for stability on the interaction of the soil used to fill the cells

of these cofferdams and the steel sheet piling. Both materials

in combination provide a satisfactory means to develop a dry

work area in water-covered sites such as ocean or lakefront or

river area construction projects.

The purpose of the cofferdam is to retain a hydrostatic

head of water as well as the dynamic forces due to currents

and waves, ice forces, seismic loads and accidental loads or to provide a lateral support to the mass of soil behind it.

However, the cofferdam is subjected to unbalanced lateral

forces acting at different heights. These unbalanced forces

will tend to produce a resultant moment which tends to

overturn the cofferdam or to produce a resultant force which

tends to slide the cofferdam on its base.

Dr. Raad Hoobi Irzooki, and Marwa Kaddori Majeed, are with Tikrit

University - Civil Engineering Department, Iraq

The resisting forces and moments against the sliding and

overturning vary in magnitude from soil to soil depending on

the unit weight, the coefficient of friction of the soil, Young’s

Modulus of elasticity, poison’s ratio, and cohesion [1].

Cellular cofferdams are usually classified according to the

configuration and arrangements of the cells. As shown in Fig.

1, the three basic types of cellular cofferdams are:

A. Circular Cells

This type consists of a series of complete circular cells

connected by shorter arcs; these generally intercept the cells at

a point making an angle, (α), of 30 or 45 degrees with the

longitudinal axis of the cofferdam, as shown in Fig. 1-a.

B. Diaphragm Cells

These cells are comprised of a series of circular arcs

connected by 120 degree intersection pieces or cross walls

(diaphragm). The radius of the arc is often made equal to the

cell width so that these have equal tension in the arc and the

diaphragm, as shown in Fig. 1-b.

C. Cloverleaf Cells

This type of cell consists of four arc walls, within each of

the four quadrants, formed by two straight diaphragm walls

normal to each other, and intersecting at the center of the cell.

Adjacent cells are connected by short arc walls and are

proportioned so that the intersection of arcs and diaphragms

can form three angles of 120 degrees, as shown in Fig. 1-c.

(a) Circular cells

(b) Diaphragm cells

(c) Cloverleaf cells

Fig. 1. Cellular cofferdams; [TVA, (2003)]

2015 International Conference on Food Nutrition and Civil Engineering (ICFNCE’2015) March 14-15, 2015 Dubai (UAE)

http://dx.doi.org/10.15242/IAE.IAE0315413 79

The design analysis and stability of cofferdams,

especially circular type, was studied analytically and

experimentally by a number of researchers as follow:

Farrokh and Robert, (1972)[2] presented the design of

circular type cellular cofferdams formulated as a nonlinear

optimization model that takes explicit account of relevant economic and technologic aspects. The objective is to

minimization of total expected cost. The geometric

programming approach provides important design insights by

yielding the proportions of the total cost to be assigned to the

cost components, fill material, sheet piling and flooding in an

optimal design.

Schroeder et al., (1977)[3] performed investigation on 12-

cell wharf at Terminal No.4 along the Willamette River in

Portland, Oregon. Individual cells are 19.74m in diameter,

spaced 25.74m center to center, a freestanding height of

20.1m, and connecting arcs which have a radius of 4.32m. He

was found that the maximum interlock force in the cell was also near the dredge line and the lateral earth pressure values

recommended by Terzaghi are adequate for design[4].

Sorota and Kinner, (1981)[5] presented a description of

design of a steel sheet pile cellular cofferdam that was

required for construction of a graving dry dock. The

cofferdam was constructed approximately 168m offshore

within the Hood Canal of Washington State and was required

to retain 24m of water after basin dewatering. Items discussed

include the need for two pumped dewatering systems, the

need for vibratory probe compaction of the cell fills, site soil

conditions, dredging, and steel sheet pile corrosion protection. Jahren, (1990)[6] stated that the sheet-pile cellular structure

is constructed by arranging straight web sheet piles in a

cylindrical shape and filling the enclosed volume with soil.

Further analysis indicates that the results are sensitive to

changes in several of the input parameters, but that the basic

findings are unchanged within the range of changes in the

sensitivity analysis.

AL-shamkey, (1992)[7] studied the analysis of stability of

circular cell in order to know the behavior of this cell under

the lateral load to back fill loads inside the cell. The

conclusion that obtained was the maximum hoop tension

sheet occurs in the same zone at the level (1/6 ) from cell height.

Mohammod et al., (2001)[8] studied the behavior of

double sheet pile wall cofferdam on sandy soil subjected to

high level of water. Test results imply that: (i) the shear

deformation of the fill dominates the failure mechanism of the

cofferdam, (ii) as the width of the cofferdam increases, the

water height at failure increases and (iii) the sheet pile wall at

the downstream is subjected to higher stresses than the sheet

pile wall at the upstream.

Peng et al., (2007)[9] based on the hydraulic computation

theory, a hydraulic numerical model describing an overflow cofferdam during multi - phase diversion was presented to

achieve the discharge capacities, stream wise water levels,

velocities of both overflow cofferdam and narrowed river.

The calculated values of this model are in good agreement

with the observed data.

Al-Rmmahi, (2009)[10] studied the design and

construction of cellular cofferdams through test models to

observe their stability. Series of laboratory tests had been

carried out on two diaphragm cells of different width to depth

ratios (0.75, 0.85, and 1). Then analysis of cellular cofferdam

by software which is known PLAXIS is used to compute

deformations, stresses, and strain in the body of cofferdam

and foundation. The functions represent the relation between

deformations and embedment depths that occurred after applied loads. Many conclusions had been drawn from this

study. One of the main conclusions is that embedment depth

is greatly effect on the resistance and deformation of the cell.

AL-Khyatt, (2009)[11] studied the stability of cellular

cofferdams through testing the models of three cases of

isolated circular cofferdams with different cell width (b) to

cell height (H) ratio (b/H), with five types of soil fill. The

results of the tests indicate the following: the cells filled with

subbase were more stable against sliding at different (b/H)

ratios, the cells filled with sand passing No.8 were more

stable against overturning at different (b/H) ratios.

AL– Kelabbee, (2010)[12] presented a study about nonlinear finite element analysis that has been used to predict

the load deflection behavior of circular cell cofferdam under

lateral load by using ANSYS (version 5.4). The full Newton-

Raphson method was used for the nonlinear solution

algorithm.

Al-Kassar, (2011)[13] studied the effect of berm and

embedment depth on stability of cofferdam in wet soils. The

results of tests declared that the resistance of cellular retaining

structure (cofferdam) with wetting soils in wet foundations

gives greater resistance than in dry soils.

Al-janabi, (2012)[14] present study of nonlinear finite element analysis predict the load deflection behavior of

cellular cell cofferdam under lateral load by using ANSYS

(version 12.1) computer program.

The main objective of this paper is studying the effect of

geometry and type of filling soil on the stability of glover-leaf

type cofferdams experimentally and analytically using

ANSYS (version 12.1).

II. MATERIALS AND METHODS

A. Testing Instruments

The following testing instruments were selected and

constructed by authors in order reach the objectives of this

study.

1) The Steel Frame

A steel frame used to carry the soil box with dimension

(900*900mm), and 700mm height. At the middle of its width

fastened knee-braced frame. A knee-braced frame made of

two angle beams (50*50 mm) and 850mm length, are welded vertically, at their bottom end, to the steel frame. The upper

side of the angles is connected by a steel beam of 200mm

length, 50mm width and 30mm thickness. A space of 150mm

is provided between the two angle beams to allow passing the

steel cable load, on each side of knee-braced frame. Finally,

two steel angle beams (50*50mm) of 470mm length, are

welded at 350mm height from knee-braced to support it.

In each angle beams, a slit-like opening with dimensions

of 650mm length and 25mm width is made at 50mm height



from the knee-braced base, this slit is use to fix the pulley

system.

1) The Loading System

The load is applied to the cell by steel cable loop 5mm in

diameter hold around the cell tightly from one end and

connected to the weight holder from the other.

The loading system consists of: 1- The dead weight holder comprises of two parts, the first is

a steel beam with dimension 300mm length, and 50mm

diameter.

2- Square steel plate of 100mm length and 10mm thickness.

The first part is welded vertically to the second part. A

different dead weights of were used as a loading unit.

2) The Pulley System

The pulley system consists of a round steel shaft 30mm in

diameter and 200mm length, a pulley 50mm in diameter was

fixed in the middle of the shaft, and two brackets each one

surrounding ball 60mm and internal diameter 30mm, the two

brackets provided with two holes that was used to fix the pulley set to the knee braced frame.

3) The Soil Box

A wooden container with inner dimensions (900*900mm),

and 200mm height, was used for modeling the cellular

cofferdams system. At a distance 150mm from the back end

of this box a steel angle beam of 920mm length, 50mm width

and 50mm height was fastened by screws above the two sides

of the box. There is one hole in the middle of the beam to

support a steel screwed shaft, 15mm diameter, and 800mm

length. The steel shaft was used to support four dial gages.

4) The Dial Gages System

Three dial gages, of 0.01mm accuracy, were used to

measure the displacement of the models throughout the entire

testing program, these dial gages were mounted to the vertical

steel shaft. Fig. 2 shows the cell loading model which was

used in this study.

Fig. 2. Glover-leaf cell testing model

B. Properties of Soil

Three different types of soils were used in all tests, the

dry density, total unit weight and angle of internal friction for

wet and dry conditions of these soils are shown in Table I.

TABLE I

THE PROPERTIES OFTHE FILLING SOILS IN THE CELL

Type of soil Dry Density

(γd)

(kN/m3)

Total unit weight

(γw)

(kN/m3)

Angle of internal

friction (ød)

(Degree)

Angle of internal

friction (øw)

(Degree)

Symbol of soil

Subbase 17.37 19.014 38 36 GM

Sand Passing on Sieve

No.4

15.573

17.455

34

32

SP

River sand 14.3 14.54 31.5 30 SM

C. Experimental Testing Program

In all experimental tests, the soil filling the steel box was

compacted by vibrator to provide uniformly dense bed soil for models which were used in the study [14]. Three types of

soils were used in the experimental tests; for each test the

same type of soil was used as cell fill and foundation, and

two cases of soils were used (dry and wet). Water content,

dry density, direct shear test were executed for all soil types,

the wetting unit weight was found. The second test tries to

find the angle of internal friction (Ø). The glover-leaf cell

was then filled with dry or wet soil at three layers and

compacted carefully. This cell was located on the middle of

foundation testing box, three different types of clover leaf

cells were tested, see Fig. 3, these types have bed width to

height ratio (b/H) equal to (1.0, 0.85, and 0.75). All types of clover leaf cells were tested by applying loads at three

different location heights from the base, 100mm, 150mm,

and at the top point of model, 300mm. Two different

conditions for applying loads, the first applied on two leafs

and the second on one leaf (neutral or longitudinal

directions).

Fig. 3. Glover-leaf cells

III. THEORETICAL MODELING

(ANSYS+CivilFEM), is a finite-element analysis

package, is used to simulate the response of a physical

system to structural loading, and thermal and electromagnetic

effects. (ANSYS+CivilFEM) uses the finite-element method to solve the underlying governing equations and the

associated problem-specific boundary conditions. The

SOLID45 element has been used in the modeling of soil and

steel. This element is defined by eight nodes having three

degrees of freedom at each node: translations in the node’s x,



y, and z directions. The element has plasticity, creep,

swelling, stress stiffening, large deflection, and large strain

capabilities. Loads are described in Node and Element

Loads. Pressures may be input as surface loads on the

element faces. Positive pressures act into the element

temperatures and fluencies may be input as element body loads at the nodes. The geometry and node locations for this

element are shown in Fig, 4, [15].

Fig. 4 SOLID45 element [ANSYS12.1, (2010)][14]

A. Nonlinear Solution

The finite element discrimination process yields a set of

simultaneous equations [14].

[K]{u}={Fa} (1)

Where:

[K] = coefficient matrix. N.m

{u} = vector of unknown DOF (degree of freedom) values.

{Fa} = Vector of applied loads.

(ANSYS + CivilFEM) employs the "Newton - Raphson"

approach to solve nonlinear problems. In this approach, the

load is subdivided into a series of load increments. The load

increments can be applied over several load steps, illustrates

the use of Newton-Raphson equilibrium iterations in a single

DOF nonlinear analysis[14].

Parameters needed to define for the models material such

as (density, angle of internal friction, ect), there are two parts of the material model for each element.

Material model number 1 consisting of soil filling the cell

and foundation and material model number 2 refers to the

steel sheet pile. The SOLID45 element was being used for

modeling the filling material of cofferdam and steel sheet

pile for the cofferdam.

B. Material Properties

Parameters needed to define the material models can be

found in Table II. As shown in this table, there are two parts

of the material model for each element.

C. Cloverleaf Cofferdam in (ANSYS+CIVIL FEM)

Cloverleaf cofferdam was in depth of 300mm, and width

of (300,255 and 225 mm) respectively. The dimensions of the

foundation base (X=900mm, Y=900mm, Z=200mm), Fig. 5

shows the details of cofferdam geometry. The sand river soil

was used in the program model in dry and wet cases. The load

was applied at one third of height 100mm.

Fig. 5-a: Clover leaf Cofferdam and foundation in longitudinal

direction

Fig. 5-b: Clover leaf Cofferdam and foundation in neutral

direction

TABLE II

MATERIAL PROPERTIES

Material Model

Number Element Type

Material Properties

River sand soil

1

SOLID45

𝐸soil Young’s modulus (𝑁/𝑚2) 13*10

3

𝜐soil Poisson’s ratio 0.3

𝜌wet Density of wet soil(𝑘g⁄m3) 1480

𝜌dry Density of dry soil (𝑘g⁄m3) 1457.69

𝐶d Cohesion in dry case(𝑘𝑁⁄m2) 3

𝐶w Cohesion in wet case(k𝑁⁄m2) 5

𝜙d Angle of Friction in dry case 31.5

𝜙w Angle of Friction in wet case 30

2

SOLID45

Steel

𝐸s Young’s modulus (𝑁⁄m2) 201*10

9

𝜐s Poisson’s ratio 0.3

𝜌s Steel Density (𝑘g⁄m3) 7865



IV. RESULTS OF EXPERIMENTAL TESTS

Figs. 6 to 14 represent the relationship between the lateral

load and displacement for experimental tests on glover-leaf

cofferdam cells filling with different soil types and for

applying load at 100mm height from the base only. From

these figures it can be seen the following:-

1-The displacement is linearly proportional to applied load at

the beginning and after that, the curves show non linearly

displacement proportional with load, and then the load-

displacement relationship become again linear with failure

occurrence.

2- For all tests, the displacement of cell which was filled with wet soil is resist more than the cell with dry soil when

applying same load on these two cells. This is because the

weight of wet soil is more than the dry soil, in spite of the

friction between the wet soil and the foundation soil is less

than the friction between the dry soil and the base.

3- The cells filled with subbase was resist more than the two

other soils because the density of subbase is more than the

two other soil, so that the cell which fill with subbase will be

have more weight when the volume was constant.

4- The longitudinal direction of clover leaf cell expressed

more resistance than the neutral direction because the

increasing in the length side that versus to load. 5- By making comparison between the experimental results

of the present study with the experimental results of (Al-

kassar, 2001)[13] which used circular cofferdam cell was

filled with saturated soils (subbase, sand passing sieve

No.4 and river sand) and (b/H) equal to (0.75 and 1), this

comparison show that the failure load required for glover-leaf

cofferdam is more than that load required for circular cell as

following:

- For neutral direction (130-190%) with (b/H)=0.75

- For neutral direction ( 40-80%) with (b/H)=1

- For longitudinal direction (160-250%) with b/H=0.75

- For longitudinal direction (50-100%) with b/H=1

From the above results it can be seen that the glover-leaf

cofferdams is more stable than other types.

Fig. 6. Horizontal displacement and lateral load relationship for

sand (Load at 100mm height and, 𝐛/𝐇=0.75)


river sand (Load at 100mm height and, 𝐛/𝐇=0.75)


subbase (Load at 100mm height and, 𝐛/𝐇=0.75)


sand (Load at 100mm height and, 𝐛/𝐇=0.85)



Fig.10. Horizontal displacement and lateral load relationship

for river sand (Load at 100mm height and, 𝐛/𝐇=0.85)

Fig. 11. Horizontal Displacement and lateral load relationship for

subbase (Load at 100mm height and, b/H=0.85)

Fig. 12: Horizontal displacement and lateral load relationship for

sand (Load at 100mm height and, b/H=1)


river sand (Load at 100mm height and, b/H=1)


subbase (Load at 100mm height and, b/H=1)

V. RESULTS OF THEORETICAL ANALYSIS

Figs. 15 to 26 show the comparison between the

theoretical and experimental results of applied load with

lateral displacement for cloverleaf cofferdam cell using

different (b/H) ratios (0.75, 0.85 and 1), different cases of

soil (wet and dry), different cases of cell location

(longitudinal and neutral) and for case of applying load at

height 100mm from the base. These figures concluded a good

agreement between the results of the above two methods.

Fig.15. Comparison between ANSYS and experimental results for

dry river sand in neutral direction for b/H=0.75




dry river sand in longitudinal direction for b/H=0.75

Fig,17. Comparison between ANSYS and experimental results for

wet river sand in neutral direction for b/H=0.75


wet river sand in longitudinal direction for b/H=0.75


dry river sand in neutral direction for b/H=0.85

Fig. 20. Comparison between ANSYS and experimental results for

dry river sand in longitudinal direction for b/H=0.85


wet river sand in neutral direction for b/H=0.85



Fig, 22. Comparison between ANSYS and experimental results for

wet river sand in longitudinal direction for b/H=0.85


dry river sand in neutral direction for b/H=1

Fig. 24. Comparison between ANSYS and experimental results

for dry river sand in longitudinal direction for b/H=1


wet river sand in neutral direction for b/H=1

Fig. 26. Comparison between ANSYS and experimental results for

wet river sand in longitudinal direction for b/H=1

VI. ARTIFICIAL NEURAL NETWORK (ANN) MODEL

Artificial Neural Network (ANN) is powerful solution to

many complex modeling problems. Many studies have

demonstrated that the (ANN) models are very successful in

hydraulic maters [16, 17, 18]. ANN is an information

processing system that is inspired by the biological nervous

system, such as brain.

The human brain is composed of large number of

interconnected processing elements (neurons). Due to structure in which the neurons arranged and operate, human

are able to quickly recognize patterns and process data. An

(ANN) is a simplified mathematical representation of

biological neural network. It has the ability to learn from

examples, recognize a pattern in the data, adapt solution over

time, and process information[17]. There are many different

types of artificial neural networks in terms of structure and

mode of operation. In this study, one of the most popular



neural networks is examined, the widely used multilayer

perceptron (MLP) network.

Artificial Neural Network is a layered network of artificial

neurons. The neurons or nodes are generally arranged in

parallel to form layers. The first layer, which receives the

inputs, is called input layer and the last layer is called output layer. The rest are hidden layers whose depend on the

problem to be solved.

The input layer which takes the input values from the

outside. All the nodes of the input layer from the inputs of the

neural network. The nodes of the output layer send the

output values to the user’s external environment[19]. The

hidden layers are the processing center of network system.

The weights are adjusted in an iterative manner to achieve

the expected output values. A typical artificial neural is

shown in Fig. 27.

The number of nodes in input and output layer are fixed

according to the number of dependent and independent variable in the training data, while the selection of an optimal

number of nodes in the hidden layer depend on the specific

problem. If the number of neurons is small in hidden layer,

the network may not learn the process correctly. On the other

hand if the number is too high, the training will take a long

time and the over fitting of the training data may produce

[17].

Fig. 27. Typical Artificial Neural Network

VII. RESULTS OF ANN

The SPSS.17 software application allows the selection

of data division into training set. The (ANN) model

comprised of four neurons in the input layer the input data

namely (b, ɣ (Gama), (b/H) and y), the output value was the

failure force (F). The most suitable data division found here

to be 68.5% in neutral direction (37 runs) for training and

31.5% (17 runs) for testing. Also, the most suitable data

division found for longitudinal direction is 68.5% (37 runs)

for training and 31.5% (17 runs) for testing. Table III shows

the relative importance for each input variable in neutral and

longitudinal directions. TABLE III

THE RALATIVE IMPORTANCE OF VARIABLES

From the above table it can be seen that the most important

variable in the stability of glover-leaf cofferdams, in each

direction, is the density of filling soil (γ), while the bed

width of the cell (b) has a little importance.

VIII. CONCLUSIONS

In the present research, the effect of geometry and soil

type on the stability of glover-leaf cofferdams was

investigated experimentally and theoretically. This study

concludes to the following:

1- The clover leaf cells filled with wet subbase were more

stable against sliding and overturning at different (b/H)

ratio. 2- For all tests, the displacement of clover leaf cell which

was filled with wet soil expressed more resistance than

the cell with dry soil when applying same load on these

two cells.

3- The cells that put on the longitudinal direction were more

stable against sliding and overturning at different (b/H)

ratios, because the increase of the opposite load side of

the loading cell.

4- In general, the results obtained using the finite element

models represented by the load applied at one third of the

cell cofferdam height for river sand deflection curves show good results with the experimental. The difference

between the numerical ultimate loads and the

corresponding experimental ultimate loads is in the range

between (0-6.9)%.

5- The glover-leaf cofferdam has more resistance and it’s

more stable than other types against applying load.

6- By using Artificial Neural Network (ANN) program, the

importance of each effecting variables determined in

neutral and longitudinal direction, the results show that

the density of soil is the bigger effect variable on the

failure loading with effect ratio (35.3%) in neutral

direction and (36%) in longitudinal direction. The

effectiveness of , loading height(y) and the cell

position (B) in neutral and longitudinal direction was

(10.2%, 33.3%, 21.2%), (18.6%, 31.9%, 13.5%)

respectively.

REFERENCES

[1] K. M. Nemati,"Temporary structure cofferdam", Department of

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[3] W. L. Schroeder, D. K. Marker, and T. Khuayjarempanishk,

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Vol.103, No. GT3, pp. 153-168, 1977.

Input

Variable

Neutral Direction Longitudinal Direction

Importance Normalized

Importance Importance

Normalized

Importance

b

γ (Gama)

b/H

y

0.130

0.426

0.148

0.296

30.4%

100%

34.7%

69.5%

0.135

0.360

0.186

0.319

37.5%

100%

51.7%

88.8%



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[13] H. M. Al-kassar, "Experimental study of the stability of the cellular

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http://dx.doi.org/10.1623/hysj.48.3.349.45288

[17] O. Kisi, "Daily river flow forecasting using artificial neural

networks and auto-regressive models", J. Eng. Sci., 2005, pp. 9-20.

[18] R. Teschl and W. L Randue. A neural network model for short term

river flow prediction", Nat. Hazards Earth Syst. Sci., 6, 2006, pp.

629-635.

http://dx.doi.org/10.5194/nhess-6-629-2006

[19] M. S. Erdurmaz, "Neural network prediction of tsunami parameters

in the Aegean and Marmara seas. M.Sc. thesis. Middle East

Technical University, 2004.

Dr. Raad Hoobi Irzooki, birth in Iraq, Baghdad,

October-1963, Assistant Professor, B.Sc. in Water

Resources Engineering from Baghdad University,

Iraq in 1985. M.Sc. in Water Resources

Engineering – Hydraulic Structures from Baghdad

University in 1991. Ph.D. in Building and

Construction Engineering-Water Resources

Engineering from University of Technology, Iraq

in 1998. Areas of Expertise: Hydraulic Structures and Seepage Through

Earth Dams.

He is instructor in the College of Engineering – Tikrit University, Iraq

from 1992 till now. He is a head of Civil Engineering in Tikrit University

from 2001 to 2003 and the director of consulting engineering bureau from

2007 to 2011.

Dr. Irzooki issued supervised more than 20 Ph.d , M.Sc. and Higher

Diploma students and published 15 papers in local and international

journals. E-mail: [email protected]

Marwa.k Majeed from Iraq, Samarra, birth in June

1990, B.Sc. in Civil Engineering 2012 from Tikrit

University, Iraq, She is a master Student in Tikrit

university too.

She is work as a lecturer in Engineering College in

Samarra University.











studying the effect of geometry and type of soil on the...

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