Resources · Research Data
Research tools
Tools the SP3 Team built during its research — free to reuse so you don't have to duplicate work that is already done.
This page collects four sets of tools from our research program:
- Excel tools for computing calibrated model parameters for reinforced concrete elements
- A dynamic solution algorithm for use with OpenSees analyses
- Collapse animation videos showing selected results of nonlinear dynamic collapse simulations
- A packaged single-degree-of-freedom model in OpenSees, including MATLAB pre- and post-processors
Reinforced concrete component calibration tools
Two simple Excel tools for calibrated RC component modeling.
RC element backbone tool
Computes predicted component parameters (inelastic deformation capacity, etc.) for an RC column failing in flexure or flexure-shear. Excel (.xls)
Yield moment spreadsheet
Computes the yield moment, based on the ACI publication by Panagiotakos and Fardis (2001). Excel (.xls)
Dynamic solution algorithm for OpenSees
Numerical stability was a persistent problem throughout our collapse work in OpenSees; we developed these algorithms over several years to get past the numerical issues. The full algorithm has some complications that are not easy to follow in the code (it checks the nodal displacement output to search for singularity, etc.), so two file sets are provided.
Simplified solution algorithm
A reduced version without the complications — the place to start for a general idea of how the algorithm is structured. ZIP
Full solution algorithm
The complete algorithm plus the procedure that calls it. ZIP
Collapse animation videos of RC SMF structures
These packaged videos animate the analytical collapse predictions completed as part of this research. Feel free to use them for educational purposes, with proper reference to this research. Animations are available for two ground motions at three intensity levels each, in .wmv format; the PowerPoint package includes all six videos plus summary information.
Videos are in Windows Media (.wmv) format and may require a compatible player on Mac or mobile devices.
Superstition Hills (M=6.7) · El Centro Station
40% of collapse level
Near MCE on average. WMV video
102% of collapse level
Spectral acceleration just past collapse capacity. WMV video
200% of collapse level
Spectral acceleration at twice collapse capacity. WMV video
Loma Prieta (M=6.9) · Gilroy Array #3 Station
40% of collapse level
Near MCE on average. WMV video
102% of collapse level
Spectral acceleration just past collapse capacity. WMV video
200% of collapse level
Note some numerical instability at the end of the record — after dynamic instability and large displacements have already occurred. WMV video
Full packaged set
What the videos show
The collapse videos show the progression of plastic hinging through the nonlinear dynamic analyses. This figure (from Goulet and Haselton et al. 2007) shows the final collapse mechanisms for a 4-story RC SMF subjected to many ground motions.
Video legend
A growing circle indicates the progression of plastic hinging; when the circle turns red, the plastic hinge has reached the "capping point" where strain softening (rebar buckling) occurs.
Example single-degree-of-freedom model in OpenSees
This packaged single-degree-of-freedom model uses a deteriorating component model in the OpenSees structural modeling platform, with MATLAB files included for pre- and post-processing. To use the model, start with the file Driver_RunCollapseAnaMATLAB_SDOF.m and follow the progression of the file structure.
More research resources
OpenSees structural models, ground motion sets, and the RC component calibration database from the same research program.
Structural Model Database → Ground Motion Sets