Progress 12/01/04 to 11/30/08
Outputs
OUTPUTS: The project resulted in a database for wood shear walls to be used in the design of light-frame wood buildings in the United States. This was done by developing a performance-based design framework with several key techniques proposed to the wood seismic design community. Included in this was a new, more versatile, hysteretic model for wood shear walls, a new software package that is user friendly and is now being used in several countries including the U.S., Chile, Japan, Canada, and India. Numerous technical presentations to industry in the U.S., Canada, and Japan including seminars and workshops resulted in broad dissemination of the project results. PARTICIPANTS: Weichiang Pang - Post Doctoral scholar at Texas A&M University, now Assistant Professor at Clemson University. Shiling Pei - Ph.D. student at Colorado State University; moving to South Dakota State University as an Assistant Professor. TARGET AUDIENCES: In general, the target audience was the research and practitioner seismic wood community. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The objective of the project was to develop a wood shear wall selection procedure based on lowest cost over time. This was fully accomplished by utilizing Bayesian decision theory in a loss-based framework. A software package that encompassed all of this and was not transparent to the user, i.e. it was user friendly for designers and engineers, was developed and distributed via the web page. The method was reviewed by peers and felt to be sound and thus various facets and applications have been published throughout the structural engineering and seismic literature. The full impact of the project is that loss-limiting seismic design for wood frame building can be considered an option in performance-based design.
Publications
- Pei, S. and J.W. van de Lindt. (2010). Influence of Structural Properties and Hazard Level in Seismic Loss Estimation. Engineering Structures: The Journal of Earthquake, Wind, and Ocean Engineering, In Press.
- Pei, S. and J.W. van de Lindt. (2009). Methodology for Long-Term Seismic Loss Estimation: An Application to Woodframe Buildings. Structural Safety, 31 (2009), 31-42.
- S. Pei and J.W. van de Lindt. (2009). Coupled Shear-Bending Formulation for Seismic Analysis of Stacked Shear Wall Systems, Earthquake Engineering and Structural Dynamics, 38 (2009), 1631-1647.
- S. Pei and J.W. van de Lindt. (2009). Systematic seismic design of woodframe structures for manageable loss, Earthquake Spectra, 25(4), 851-868.
- Pang, W.C., D.V. Rosowsky, S. Pei, and J.W. van de Lindt. (2007). Evolutionary Parameter hysteretic Model for PBSD Applications. ASCE Journal of Structural Engineering; 133 (8); 1118-1129.
|
Progress 12/01/06 to 11/30/07
Outputs
OUTPUTS: The goal of the project was to develop a selection procedure for wood shear walls in seismic zones, to do this required software and a methodology. The project software was completed and released via the Internet and through a large e-mailing. This is the most comprehensive software of its kind, to date. The concept of loss-based seismic design was formulated and is being released in numerous conference papers and several journal papers.
TARGET AUDIENCES: The software release was designed to provide practitioners with enough information that they can perform a basic loss-based seismic design.
Impacts
The ability to design a wood frame building in a seismic zone based on an expressed goal of limiting financial loss will provide the basis for the next generation of design codes in this area. Once fully implemented and demonstrated over the next several years the results will be seminal. The beta version of the software developed has provided the mechanism to demonstrate the methodology described above.
Publications
- Pei, S. and J.W. van de Lindt. 2007. "SAPWood: Seismic Analysis Package for Woodframe Buildings", Software Users Manual.
- Pei, S. 2007. "Loss Analysis and Loss-Based Seismic Design for Woodframe Structures." Ph.D. Dissertation, Colorado State University.
- W.C. Pang, D.V. Rosowsky, S. Pei, and J.W. van de Lindt. 2007. "Evolutionary Parameter hysteretic Model for PBSD Applications." ASCE Journal of Structural Engineering; 133(8): 1118-1129.
- Pei, S. and J.W. van de Lindt. 2007. "Seismic Design of Woodframe Residential Structures for Lifetime Loss Minimization: A Bayesian Approach." Submitted to ICASP10, Tokyo, Japan.
- S. Pei and J.W. van de Lindt. 2007. "Long-Term Seismic Loss Evaluation for Woodframe Structures: A Performance-Based Procedure." 9th Canadian Conference on Earthquake Engineering, Ottawa, Ontario, June 27-29, 2007.
|
Progress 12/01/05 to 12/01/06
Outputs
A probabilistic framework to estimate long term seismic-induced economical loss for woodframe structures has been developed. The concept of a damage fragility system which can be used to quantitively model the uncertainty in the response-damage-cost relationship is developed and applied to woodframe residential building components. Bayesian models were used in the framework in order to incorporate subjective engineering experiences and test/monitored data. Both the analytical and simulation procedures to implement the loss estimation framework were investigated with a portfolio of examples. To do this a software package is under development which will enable practitioners to design woodframe structures based on minimization of annualized losses. The project is going very well and we plan to request a one year no-cost time extension to further complete the work.
Impacts
The impact of this project will be that both researchers and practitioners will be enabled with a framework and the tools needed to optimize a woodframe structural design for earthquake damage minimization over its lifetime. To date, this has been discussed but was only conceptualized. Over the next decades the results of this work will find their way into performance-based design codes that we are developing as part of other projects and at the national committee level.
Publications
- van de Lindt, J.W., D.V. Rosowsky, S. Pei, and W.C. Pang. 2006. "Next Generation Hysteretic Models for Development of a Performance-Based Seismic Design Philosophy for Woodframe Construction." 8th National Conference on Earthquake Engineering, San Francisco, CA.
- W. Pang, Pei, S., J.W. van de Lindt, and D.V. Rosowsky. 2006. "Formulation of Evolutionary Parameter Hysteretic Models for Woodframe Shearwalls." 2006 World Conference on Timber Engineering, Portland, OR.
|
Progress 12/01/04 to 11/30/05
Outputs
Wood shear walls are the primary lateral load-resisting components in light-frame residential wood construction in the United States. Much of the design is prescriptive in nature, with engineered shearwalls typically built in more active seismic regions of the country. This work seeks to provide a logical, easy to understand, design procedure for shearwalls that will help reduce damage during earthquakes for woodframe structures in the U.S. To date, a next-generation of wood shearwalls has been formulated based on a test database gathered from numerous sources around the country. Specifically, wood shearwall data from nine universities and labs has been gathered, and is being used in conjuction with this model.Software for the preliminary design procedure is underway and should be completed during the second year of the project. This software will enable engineers to utilize the robustness of these next-generation numerical models without confusion due to details such
as parameter calibration. This is the key to eventualy implementation, i.e. a user friendly methodology for multi-criteria design. The work from the first year of the project has resulted in a new hysteretic wood shearwall model (being integrated into a full-structure software package) that will provide the accuracy and flexibility necessary to develop the new design procedure. The results of this study will have a signifcant societal impact over the next 20 years, particularly for multi-family homes, which tend to be engineered more often than single family homes. Eventually, the way that woodframe structures are designed will change for the better, resulting in signifcantly less damage during earthquakes.
Impacts
The results of this study will have a signifcant societal impact over the next 20 years, particularly for multi-family homes, which tend to be engineered more often than single family homes. Eventually, the way that woodframe structures are designed will change for the better, resulting in signifcantly less damage during earthquakes.
Publications
- No publications reported this period
|
|