3332002- Practitioner Critique of PEER Bridge Analysis Methodology

A draft outline of the I-880 Testbed Report was completed with specific assignments. Specific assignments were made one of which was made specifically for industry review with the Goals/Objectives described above. Work completed to date for this specific project includes a compilation and presentation of the historical development of the current practice used for seismic bridge design. Figure 1 illustrates the overall life cycle of a bridge and how changes are implemented into the design process. Seismic design is applied to both new bridges and upgrading existing bridges. Since the current inventory of bridges in the United States is nearly 600,000, new design methodologies should also be applicable to retrofitting existing bridges. As shown in the figure, the new methodologies will have an impact on both the “load” and “resistance” models. Additionally, some effort has been made in some of the problems related to understanding of the proposed PEER Methodology. It is currently envisioned that the new PEER methodology will help to solve some of the problems related to the current trends of increased performance and increased hazard for seismic design. As illustrated in Figure 2, it is envisioned that the “new technologies” will help to achieve these goals.

Project Title/ID Number	Practitioner Critique of PEER Bridge Analysis Methodology—3332002
Start/End Dates	10/1/02—9/30/03
Project Leader	Roy Imbsen (Industrial Collaborator)
Team Members

Project goals and objectives
Critique the newly developed PEER methodology for seismic design of bridges using a portion of the I-880 Caltrans Viaduct located in Oakland, California, i.e., I-880 Testbed.
Role of this project in supporting PEER’s vision
This project will provide PEER with the insight required to tailor the methodology for implementation into practice. Three aspects of the methodology will be evaluated to ensure future implementation. First, the value added beyond that used in current practice. Secondly, how does the application of the new methodology compare with the knowledge base of the practitioner and finally, what are the shortcomings of the new methodology
Methodology employed
A comparison will be made between the proposed PEER Methodology and current practice. The comparison will include the PEER hazard analysis, damage analysis and loss analysis methodologies with current seismic design practice.
Brief description of past year’s accomplishments and more detail on expected Year 6 accomplishments
A draft outline of the I-880 Testbed Report was completed with specific assignments. Specific assignments were made one of which was made specifically for industry review with the Goals/Objectives described above. Work completed to date for this specific project includes a compilation and presentation of the historical development of the current practice used for seismic bridge design. Figure 1 illustrates the overall life cycle of a bridge and how changes are implemented into the design process. Seismic design is applied to both new bridges and upgrading existing bridges. Since the current inventory of bridges in the United States is nearly 600,000, new design methodologies should also be applicable to retrofitting existing bridges. As shown in the figure, the new methodologies will have an impact on both the “load” and “resistance” models. Additionally, some effort has been made in some of the problems related to understanding of the proposed PEER Methodology. It is currently envisioned that the new PEER methodology will help to solve some of the problems related to the current trends of increased performance and increased hazard for seismic design. As illustrated in Figure 2, it is envisioned that the “new technologies” will help to achieve these goals.		Figure 1: Components of Bridge Design Philosophy Larger View
Figure 2: Recent Trends in Seismic Design and Retrofitting
Other similar work being conducted within and outside PEER and how this project differs
There is no known work currently being done that is focused specifically on seismic design of bridges.
Plans for Year 7 if this project is expected to be continued
It is anticipated that the I-880 Testbed Report will be completed and the methodology will be ready for implementation into practice. Completing the report will require completion of the Decision Variables (DV’s) and the Damage Measures (DM).
Describe any instances where you are aware that your results have been used in industry

Expected milestones
Publication of the I-880 Testbed report.
Deliverables
Contributing Chapter(s) from this project.