process of seismic simulationprocess of seismic simulation of a...

Process of Seismic SimulationProcess of Seismic Simulation of a 2-Bay, 2-Story RC Building

Michelle StadelNSF Summer Scholar University of Houston

OVERVIEWOVERVIEW

• National Center for Research on Earthquake qEngineering project

• Open System for EarthquakeEngineering Simulation

• Basics of Tcl/Tk script• 2D Frame example simulation• NCREE structure simulation

R l• Results• Additional research

NCREE Projectj

St d ff t f t i d lti• Study effects of torsion and multi-directional loading on RC structure

• Study real-time data and incorporate computer simulations for applications beyond the project

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OpenSeesOpen System for Earthquake Engineering Simulation

• Developed by Pacific Earthquake Engineering Research Center & the University of California, Berkeley

• Object-oriented framework for finite element analysis

• Uses Tcl/Tk script

BBasics of Tcl/Tk Script

Basic syntax -- Command argument1 argument2

Example: expr 20 + 10

The set command writes and reads variables.

$ ll i l d fi d i bl$ recalls previously defined variables.

M d l f O SModules for OpenSees

MODEL RECORDER ANALYSIS

Defines: Creates an output Defines objects Defines:

• Coordinate system

• Beams

Creates an output file that records data of interest to the programmer.

e es objec snecessary for performing the analysis

• Columns

• Materials

• Cross-sections

2-D frame problem2 D frame problem

ModelingModeling

• ModelModel• Node

C t i t Column cross section• Constraints• Materials

Column cross-section

• Section• ElementElement• Load

Beam cross-section

RecorderRecorder# Define LATERAL LOADS ---------------------------# Define LATERAL LOADS pattern Plain 1 Linear {

# nodeID Fx Fy Mz# nodeID Fx Fy Mzload 15 100.0 0.0 0.0

}}# Create RECORDERS --------------------------------recorder Node file Node15 out time node 15recorder Node -file Node15.out -time -node 15 -dof 1 disp

AnalysisAnalysissystem BandGeneralconstraints Transformationnumberer RCMtest NormDispIncr 1.0e-12 50 0algorithm Newton integrator DisplacementControl 15 1 0.1analysis Staticinitializeanalyze 50

2-D frame results Ulti t St th2 D frame results70

Ultimate Strength64 kips

50

60

30

40

Load

(kip

s)

Ruptures at 63 kips

10

20

L

Modulus of Elasticity

00 2 4 6 8 10 12

Displacement (inches)

2-story 2-bay RC building2 story, 2 bay RC building

Column cross-section

2-story, 2-bay2 story, 2 bay RC building

Beam cross-section

Model differences:

• Numbering of nodes

C tiBeam cross section • Cross-sections

• Section aggregators

• Loadingg

• Shear walls

Shear WallsShear Walls• Reinforced concrete plane• Reinforced concrete plane

stress elements• Modeled by standard brick• Modeled by standard brick

elementM t i l l ti i t i• Material – elastic isotropic

600

700

ResultsResults400

500

600

ad (k

N)

ResultsResults100

200

300Loa

00 1 2 3 4 5

Displacement (mm)

On-going Researchg g• Work is continuing to fine tune to the

OpenSees program to simulate the structure’s response to earthquake loading.

• The structure is set to be tested next week in Taiwan.

References• Howser, Rachel, A. Laskar, Y.L. Mo. (2007) “Seismic Interaction of Flexural

Ductility and Shear Capacity in Reinforced Concrete Columns.”• Hwang, S.J., M. Saiid Saiidi, Sara Wadia-Fascetti, JoAnn Browning, Jerry P. Lynch,

Kamal Tawfig, K.C. Tsai, G. Song, Y.L. Mo. (2006) “Experiments and Simulation of Reinforced Concrete Buildings Subjected to Reversed Cyclic Loading and Shake Table Excitation.”

• Mazzoni Silvia Frank McKenna Michael H Scott Gregory L Fenves et al• Mazzoni, Silvia, Frank McKenna, Michael H. Scott, Gregory L. Fenves, et. al. (2006). “Open System for Earthquake Engineering Simulation User Command-Language Manual,” Pacific Earthquake Engineering Research Center, UC Berkeley, http://opensees.berkeley.edu/OpenSees/manuals/usermanual/index.html.

• Pacific Earthquake Engineering Research Center (PEER). (2001) “Open System for Earthquake Engineering Simulation.” http://peer.berkeley.edu/news/2001spring/opensees.htmlS h d D i l (2006) “S i i h S i A hi ”• Schwerd, Daniel. (2006) “Scriptics.com – the Script Archive.” http://dev.scriptics.com/software/tcltk/.

• Tseng, Chien-Chuang. (2006) Experiment of Reinforced Concrete Building Frame PresentationPresentation.

• http://bi-directional.blogspot.com/

AcknowledgementThe research study described herein wasThe research study described herein was

sponsored by the National Science Foundation under the Award No EEC-Foundation under the Award No. EEC

0649163. The opinions expressed in this study are those of the authors and do notstudy are those of the authors and do not

necessarily reflect the views of the sponsorsponsor.