OpenSees Example 8. generic 3D Frame, NStory NBayX NBayZ, Reinforced-Concrete Section & Steel W-Section

Introduction

• Just like Example 6 for the 2D frame, this example utilizes Tcl variable-substitution and array-management tools to optimize the building of the numerical model of a generic 3D frame.
• The user is prompted for the number of stories and the number of bays (the can also be fixed in the input file).
• The same items for 3D modelling as the frame shown in Example 7 are considered here.
• For this example, there is one model-building file with many options for the model. In addition to specific dynamic-analysis files, there is also a dynamic-analysis file where the user is given the option of which dynamic analysis to perform.

Input

Model Building

• The following tasks are performed when building the model

• define units
• define model
• define recorders for output
• define & apply gravity

• The only difference between the two input files is in modelling the element section properties and calculating beam and column weight/mass.

Steel W Section Files Ex8.genericFrame3D.build.Wsec.tcl LibUnits.tcl Wsection.tcl DisplayPlane.tcl DisplayModel3D.tcl Notes 3D building frame: Steel W sections for both columns and beams. (variable elastic or fiber section) As of OpenSees version 3.2.2, you need to define torsion for the 3D fiber sections (https://wp.me/pbejzW-9X)

RC Section Files Ex8.genericFrame3D.build.RCsec.tcl LibUnits.tcl LibMaterialsRC.tcl BuildRCrectSection.tcl DisplayPlane.tcl DisplayModel3D.tcl Notes 3D building frame: Reinforced-concrete rectangular sections for both columns and beams. (variable elastic or fiber section) As of OpenSees version 3.2.2, you need to define torsion for the 3D fiber sections (https://wp.me/pbejzW-9X)

Lateral-Load Analysis

The following tasks are performed in the analysis

• define lateral-load parameters
• analyze

Static Static Pushover Files Ex8.genericFrame3D.analyze.Static.Push.tcl LibAnalysisStaticParameters.tcl Notes One-directional monotonic displacement-controlled static loading Static Reversed Cyclic Files Ex8.genericFrame3D.analyze.Static.Cycle.tcl LibAnalysisStaticParameters.tcl LibGeneratePeaks.tcl Notes One-directional displacement-controlled static loading Displacement cycles are imposed in positive and negative direction

Dynamic EQ Ground Motion Dynamic Uniform Sine-Wave Ground Motion Files Ex8.genericFrame3D.analyze.Dynamic.sine.Uniform.tcl LibAnalysisDynamicParameters.tcl Notes Sine-wave acceleration input Same acceleration input at all nodes restrained in specified direction Dynamic Uniform Earthquake Ground Motion (typical) Files Ex8.genericFrame3D.analyze.Dynamic.EQ.Uniform.tcl LibAnalysisDynamicParameters.tcl ReadSMDFile.tcl H-E12140.AT2 Notes Earthquake (from file) acceleration input Same acceleration input at all nodes restrained in specified direction Dynamic Multiple-Support Sine-Wave Ground Motion Files Ex8.genericFrame3D.analyze.Dynamic.sine.multipleSupport.tcl (this file may need to be corrected for displacement input) LibAnalysisDynamicParameters.tcl Notes Sine-wave displacement input Different displacements are specified at particular nodes in specified directions Dynamic Multiple-Support Earthquake Ground Motion Files Ex8.genericFrame3D.analyze.Dynamic.EQ.multipleSupport.tcl (this file needs to be corrected for displacement input) LibAnalysisDynamicParameters.tcl ReadSMDFile.tcl H-E12140.DT2 (Displacement recording) Notes Earthquake (from file) displacement input Different displacements are specified at particular nodes in specified directions Dynamic Bidirectional Earthquake Ground Motion (typical) Files Ex8.genericFrame3D.analyze.Dynamic.EQ.bidirect.tcl LibAnalysisDynamicParameters.tcl ReadSMDFile.tcl (need to modify ReadSMDFile.tcl for displacement data) H-E12140.AT2 H-E01140.AT2 (acceleration recording in perpendicular direction) Notes Earthquake (from file) acceleration input Different ground motion in two directions Same acceleration input at all nodes restrained in specified direction

Run

The model and analysis combinations for this example are numerous. The following are an small subset, for demonstration purposes:

• To run W-Section Model, Static Pushover Analysis:

puts " -------------Elastic Model -------------"
puts " -------------Static Pushover Analysis -------------"
source Ex8.genericFrame3D.build.Wsec.tcl
source Ex8.genericFrame3D.analyze.Static.Push.tcl

• To run RC Model, Uniform Earthquake Excitation

puts " -------------Uniaxial Inelastic Section, Nonlinear Model -------------"
puts " -------------Uniform Earthquake Excitation -------------"
source Ex8.genericFrame3D.build.RCsec.tcl
source Ex8.genericFrame3D.analyze.Dynamic.EQ.Uniform.tcl

Notes

In this example, the following items are variables:

• Number of stories in Y direction
• Number of bays in X direction
• Number of bays in Z direction
• Elastic/Fiber Section
• Display: none/node numbering/deformed shape/mode shape (can choose which mode) (variable display scaling factor for both the deformed shape and the mode shape, this scaling factor is dependent on the user choice)

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