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From PEERBridgePBEEWiki
WELCOME!
BridgePBEE is a PC-based graphical pre- and post-processor (user-interface) for conducting Performance-Based Earthquake Engineering (PBEE) studies for bridge-ground systems. The finite element computations are conducted using OpenSees of the Pacific Earthquake Engineering Research (PEER) Center. The analysis options available in BridgePBEE include: 1) Pushover Analysis, 2) Single 3D Base Input Acceleration Analysis and, 3) Full Performance-Based Earthquake Engineering (PBEE) Analysis.
Note: It is best to use a relatively new Laptop or Desktop with a fast processor, and at least 2 Gig of memory.
The following steps describe how to download, install and run BridgePBEE. For detailed documentation, please see Step 5. In addition, A few demo examples are available in Step 6.
Step 1: Install Tcl
If you have not installed Tcl/Tk on your computer, please download the Tcl/Tk 8.5 installation file below and double-click it to install (OpenSees employs Tcl 8.5). You only need to do this step once for a given PC.
Tcl 8.5
Step 2: Install Java
Most likely you should already have Java installed on your computer. If you don't, please download the installation file below and install the Java software.
Java
Step 3: Install BridgePBEE
Please download the installation file below, and then double-click on the icon and follow the simple installation instructions (you may wish to visit this site periodically to check for updates).
Download BridgePBEE_Setup.exe (Ver 1.0.1, updated 11/9/11)
Step 4: Run BridgePBEE
1) After installing the software on your computer, double-click the BridgePBEE icon to start.
2) To conduct a pushover analysis, click Pushover Analysis in the main window. To conduct single motion analysis or PBEE analysis, click Ground Shaking. For the default mesh, a typical Pushover analysis will be performed in about 5 minutes or less, and a typical earthquake simulation will consume about 20 - 60 minutes. For earthquake analysis with bridge on a rigid base (please see example files below), the runs will be very fast (about 5 minutes each). It is recommended first to do simpler runs such as the bridge on a rigid base earthquake scenario (particularly when exploring a full PBEE analysis with 100s of earthquake motions).
3) To open an existing model, click File in Menu and then click Open Model to open a model (the model file must have an extension of .pbe).
4) Click Execute in Menu and then click Save Model & Run Analysis to conduct the finite element simulation.
Step 5: Download BridgePBEE User Manual
BridgePBEE_UserManual.pdf (5 MB; updated 9/29/11)
This manual includes sections on:
1) Input Interface,Pushover, and earthquake Analysis.
2) Output Interface: For pushover analysis or single earthquake motion analysis, the output interface in BridgePBEE includes Bridge Column Response Time Histories and Profiles, Column Response Relationships, Abutment Responses, and Deformed Mesh.
3)For PBEE analysis scenarios: i) Eleven different intensity measures and response spectra for each input motion are calculated on the fly and are available for display in table and plot formats. After conducting the PBEE analysis eleven different Performance Group (PG) Quantities are also available. In addition Ground surface and Bridge Peak Accelerations (for all motions) are also available to display against any of the eleven intensity measures. Note that the PG quantities can be displayed against the base shaking intensity measures or alternatively against the computed ground surface motions intensity measures.
Click here to view the 11 PGs
Finally, values of the above PGs will trigger certain repairs according to an embedded logic (that is actually mostly automatically modified according to the specified model properties such as percent steel in the bridge column or size of gap between bridge and abutment). The necessary repairs are defined by 29 prescribed repair quantities. Each quantity contributes to an already defined level to the overall repair cost as dictated by the PG values.
Click here to view the 29 repair quantities
The final results will be displayed against any of the 11 available intensity measures (for each employed earthquake motion)in terms of:
- Contribution to expected repair cost ($) from each repair quantity
- Contribution to repair cost std. dev. ($) from each repair quantity
- Contribution to expected repair cost ($) from each performance group
- Total repair cost ratio (%)
- Total repair time (CWD) where CWD stands for Crew Working Day
- Contribution to expected repair time (CWD) from each repair quantity
4) Hazard Assessment for Any User Specified Geographic Location:
The user is also able to specify a Seismic Hazard for a particular geographic location of this bridge system in terms of specified values for any IM (e.g., derived from USGS seismicity maps). Based on this local site Seismic Hazard, losses are estimated and displayed graphically as:
- The defined local site Hazard curve as a Mean annual frequency of exceedance (ground motion)
- Mean annual frequency of exceedance (Loss) against total repair cost ratio
- Return period against total repair cost ratio
5) Mesh Generation: This section describes how to build the finite element mesh in BridgePBEE.
Step 6: Download Demo Examples
| Example 1 | Monotonic Longitudinal Pushover of a Single-Bent Bridge on Rigid Ground |
| Example 2 | Single 3D Motion Analysis of a Single-Bent Bridge on Rigid Ground |
| Example 3 | PBEE Analysis of a Single-Bent Bridge on Rigid Ground |
| Example 4 | Single 3D Motion Analysis of a Single-Bent Bridge on Soil Mesh |
| Example 5 | PBEE Analysis of a Single-Bent Bridge on Soil Mesh |
Example 1: Monotonic Longitudinal Pushover of a Single-Bent Bridge on Rigid Ground
This example demonstrates a pushover analysis of a single-bent bridge on rigid ground (Fig. 1). A longitudinal displacement of 0.2 m was applied at the bridge deck (at the column top) in 40 steps (the longitudinal direction refers to the bridge deck axis).
Click the link below to download the input file:
Download DemoRock.zip (0.2 MB)
Steps on how to run Example 1:
1) After downloading the above file, unzip it to a convenient location (folder). After unzipping the .zip file, you will see a file named DemoRock.pbe.
2) Start BridgePBEE, click File in Menu and then click Open Model to open the DemoRock.pbe file.
3) Click File in Menu and then click Save Model As to save to a different name (DemoRock.pbe is a read-only file and cannot be overwritten).
4) Click Execute in Menu and then click Save Model & Run Analysis to run the finite element analysis.
5) When the analysis is complete, a window will pop up to display the column longitudinal displacement response profile. Click the dropdown list boxes available in the window to see other response profiles or response time histories for the column.
6) Click Display in Menu and then click other (enabled) menu items to see more output. For more information, see documentation in Step 5.
Example 2: Single 3D Motion Analysis of a Single-Bent Bridge on Rigid Ground
This example performs a single 3D earthquake motion simulation of a single-bent bridge on rigid ground (Fig. 1).
Some brief information about the available input motion data sets will be presented first:
Input Motion Sets
Motion Set 1: These 100 motions were obtained directly from the PEER NGA database and all files have been re-sampled to a time step of 0.02 seconds. This PBEE motion ensemble (Medina and Krawinkler 2004) obtained from the PEER NGA database (http://peer.berkeley.edu/nga/) consists of 100 3D input ground motions, sorted into 5 bins. Each motion is composed of 3 perpendicular acceleration time history components (2 lateral and one vertical). These motions were selected through earlier efforts (Gupta and Krawinkler, 2000; Mackie et al., 2007) to be representative of seismicity in typical regions of California. The motions are divided into 5 bins of 20 motions each with characteristics: i) moment magnitude (Mw) 6.5-7.2 and closest distance (R) 15-30 km, ii) Mw 6.5-7.2 and R 30-60 km, iii) Mw 5.8-6.5 and R 15-30 km, iv) Mw 5.8-6.5 and R 30-60 km, and v) Mw 5.8-7.2 and R 0-15 km. The engineering characteristics of each motion and of the ensemble overall may be viewed directly within BridgePBEE. Alternatively, a pdf file may be downloaded, showing these characteristics (for these motions at their original sampling time step, please click here to download the pdf file, 44 M in size). The provided ground motions are based on earlier PEER research (Mackie and Stojadinovic 2005).
Motion Set 2: These motions (160 in total) are developed by Dr. Mackie from the 80 motions of set1 (excluding the 20 motions of SET1 in the bin NEAR), to account for site classification (NEHRP C and NEHRP D). The magnitude, distance, and spectral shape were intended to be similar to the previous bins (and indeed all of the previous motions appear in either the C or D bins now). As such, these motions are divided into 8 bins (compared to the 4 bins of set1, where NGA efforts had determined that site category was not accounted for adequately).
Motion Set 3: These motions (80 in total) are labeled Broadband_* (separated into the two bins, Broadband rock and Broadband soil) as developed by Professor Jack Baker for PEER. Additional information about these motions is available at the website: http://peer.berkeley.edu/transportation/gm_peer_transportation.html
The only outlier in all of this is the Near bin, but this is also documented in my old PEER report. It is a by-product of some old studies by Allin Cornell and his students.
Motion Set 4: These motions (260 in total) include the above Set2 and Set3 as well as the additional Bin NEAR of Set1 (consistent with the original LMSR, etc bins, only with closest distances less than 10km).
Once an input motion data set is specified, the user BridgePBEE interface will extract/calculate Intensity Measures (IMs) for each of these motions. In total, 11 different Intensity Measures are defined for each motion (and presented to the user in table and graphical forms), including quantities such as Peak Ground Acceleration (PGA), Peak Ground Velocity (PGV), Arias Intensity (AI), and so forth.
Now back to Example 2, where the single earthquake input was chosen from those of Motion Set 1.
Click the link below to download the input file of Example 2 (for Motion Set 1):
Download DemoRockEQ1FullMotion.zip (3 MB)
Steps on how to run Example 2:
1) After downloading the above file, unzip it to a convenient location (folder). After unzipping the .zip file, you will see a file named DemoRockEQ1FullMotion.pbe and a folder called DemoRockEQ1FullMotion_plfiles.
2) Start BridgePBEE, click File in Menu and then click Open Model to open the DemoRockEQ1FullMotion.pbe file.
3) Click File in Menu and then click Save Model As to save to a different name (DemoRockEQ1FullMotion.pbe is a read-only file and cannot be overwritten).
4) Click Execute in Menu and then click Save Model & Run Analysis to run the finite element analysis.
5) When the analysis is complete, a window will pop up to display PG quantities (with respect to an Intensity Measure, e.g., PGV, by default). Since this is a single motion analysis, only one point is displayed in the PG Quantities window.
6) Click Display in Menu and then click other (enabled) menu items to see more output. For more information, see documentation in Step 5.
Click the links below to download additional input files for Example 2 (for Motion Sets 2, 3 & 4, all sampled at 0.02 seconds of time step):
Download DemoRockEQ1FullMotion_MotionSet2.zip (5.2 MB) Download DemoRockEQ1FullMotion_MotionSet3.zip (3.8 MB) Download DemoRockEQ1FullMotion_MotionSet4.zip (9.6 MB)
Example 3: PBEE Analysis of a Single-Bent Bridge on Rigid Ground
This example demonstrates a PBEE analysis of a single-bent bridge on rigid ground (Fig. 1). Ten 3D shaking motions (2 motions from each bin of Motion Set 1) selected from a set of 100 motions were employed. To minimize the output size, no detailed output was recorded for individual motions (this is an available user option).
Click the link below to download the input file of Example 3:
Download DemoRockEQ.zip (3 MB)
Steps on how to run Example 3:
1) After downloading the above file, unzip it to a convenient location (folder). After unzipping the .zip file, you will see a file named DemoRockEQ.pbe and a folder called DemoRockEQ_plfiles.
2) Start BridgePBEE, click File in Menu and then click Open Model to open the DemoRockEQ.pbe file.
3) Click File in Menu and then click Save Model As to save to a different name (DemoRockEQ.pbe is a read-only file and cannot be overwritten).
4) Click Execute in Menu and then click Save Model & Run Analysis to run the finite element analysis. The interface allows for more than one motion to be computed at the same time (separate but simultaneous runs to reduce the overall computing time when a multi-core computer is used). The number of motions to be run at the same time is an available user option (set to 4 by default, and can be increased, to reduce overall run time, particularly for multi-core processor machines).
5) When the analysis is complete, a window will pop up to display PG quantities (with respect to an Intensity Measure, e.g., PGV, by default).
6) Click PBEE Analysis in the main window, then click Compute Repairs to view PBEE outcomes or click Display Hazard Curves to view hazard curves.
7) To view responses for an individual motion, Click Display in Menu and then click Detailed Output: Please Select Input Motion to choose a motion. And then click Display in Menu again and click corresponding menu items to see more output. For more information, see documentation in Step 5.
Additional input files for Example 3:
Click the links below to download additional input files for Example 3 (for Motion Sets 2, 3 & 4, all sampled to 0.02 seconds of time step):
Download DemoRockEQ_MotionSet2.zip (4.9 MB) Download DemoRockEQ_MotionSet3.zip (3.7 MB) Download DemoRockEQ_MotionSet4.zip (9.2 MB)
Example 4: Single 3D Motion Analysis of a Single-Bent Bridge on Soil Mesh
This case demonstrates single 3D motion simulation of a single-bent bridge on soil mesh (Fig. 2). The total number of soil elements is 1088. And the total execution time is about 50 minutes on a PC (3.2 GHz).
Click the link below to download the input file of Example 4 (for Motion Set 1):
Download DemoEQ1FullMotion.zip (3 MB)
Steps on how to run Example 4:
1) After download the above file, unzip it to a convenient location (folder). After unzipping the .zip file, you will see a file named DemoEQ1FullMotion.pbe and a folder called DemoEQ1FullMotion_plfiles.
2) Start BridgePBEE, click File in Menu and then click Open Model to open the DemoEQ1FullMotion.pbe file.
3) Click File in Menu and then click Save Model As to save to a different name (DemoEQ1FullMotion.pbe is a read-only file and cannot be overwritten).
4) Click Execute in Menu and then click Save Model & Run Analysis to run the finite element analysis.
5) When the analysis is complete, a window will pop up to display PG quantities (with respect to an Intensity Measure, e.g., PGV, by default). Since this is a single motion analysis, only one point is displayed in the PG Quantities window.
6) Click Display in Menu and then click other (enabled) menu items to see more output. For more information, see documentation in Step 5.
Additional input files for Example 4:
Click the links below to download additional input files for Example 4 (for Motion Sets 2, 3 & 4, all sampled to 0.02 seconds of time step):
Download DemoEQ1FullMotion_MotionSet2.zip (5.1 MB) Download DemoEQ1FullMotion_MotionSet3.zip (3.8 MB) Download DemoEQ1FullMotion_MotionSet4.zip (9.2 MB)
Example 5: PBEE Analysis of a Single-Bent Bridge on Soil Mesh
The users can make the input file for this example based on the Example 4 input files. Below are the steps:
1) Follow the steps described in Example 4 to open an input file (e.g., DemoEQ1FullMotion.pbe).
2) Click File in Menu and then click Save Model As to save to a different name (to avoid overwriting).
3) Click PBEE Motions in the main window. In the new window (PBEE Input Motion), click Select All to choose all motions. To randomly select a certain number of motions for each bin, click the dropdown list below the input motion list.
4) Click Execute in Menu and then click Save Model & Run Analysis to run the finite element analysis.
5) Follow the steps described in Example 3 to view results including PBEE outcomes.
References
Aviram, A., Mackie, K. R., and Stojadinovic, B. (2008). Effect of abutment modeling on the seismic response of bridge structures, EARTHQUAKE ENGINEERING AND ENGINEERING VIBRATION Report No. 4/ vol. 7 [ pdf (502.1 KB) ]
Mackie, K. R. and Stojadinovic, B. (2005). Fragility Basis for California Highway Overpass Bridge Seismic Decision Making, PEER Report No. 2005/02, Department of Civil and Environmental Engineering, University of California, Berkeley, CA. [ pdf (8.7 MB) ]
Medina, R. and Krawinkler, H. (2003). Seismic Demands for Nondeteriorating Frame Structures and Their Dependence on Ground Motions, PEER Report No. 2003/15, Department of Civil and Environmental Engineering, University of California, Berkeley, CA. [ pdf (3.1 MB) ]
