Overview of FEMA P-58 (ATC-58) Damage/Loss Methodology and Plans for Enabling Commercial Software

Transcription

1 1 Overview of FEMA P-58 (ATC-58) Damage/Loss Methodology and Plans for Enabling Commercial Software Curt B. Haselton, PhD, PE CSU, Chico Jack W. Baker, PhD Stanford University

2 Overview of FEMA P-58 2 P-58 is a performance prediction methodology based on a 10-year FEMA study (enabled by much previous research). P-58 is an alternative to other experience-based or judgment-based methods (e.g. HAZUS, ATC-13, etc.). P-58 is tailored to building-specific analysis (as opposed to regional/portfolio analyses). P-58 provides information useful for seismic ratings. ATC is currently working on another 5-year effort to further advance the methodology, implementation, ease of use. The REDi Rating System (this afternoon) also uses a modified version of FEMA P-58 in their rating process.

3 Overview of FEMA P-58 3 FEMA P-58 Output Results: Losses ($) [Repair Cost Rating] Fatalities & injuries [Safety Rating] Repair time & red tagging [Recovery Time Rating (some translation required)] Types of analysis results: Intensity-based (e.g. DBE) [Approach for ratings] Time-based (annualized values) Scenario-based (for a given event)

4 FEMA P-58: Output Examples Sample results (12-story RC frame): 4

5 FEMA P-58: Output Examples Dig as deep as you like 5

6 FEMA P-58: Methodology 6 Hazard and Ground Motions Soil and hazard curve Ground motions (if needed)

7 FEMA P-58: Methodology 7 Hazard and Ground Motions Soil and hazard curve Ground motions (if needed) Structural Responses Option #1: Response-history Option #2: Simplified method

8 FEMA P-58: Methodology 8 Hazard and Ground Motions Soil and hazard curve Ground motions (if needed) Structural Responses Option #1: Response-history Option #2: Simplified method Damage Prediction Contents (str. and non-str.) Fragility curves

9 FEMA P-58: Methodology 9

10 FEMA P-58: Methodology 10 Hazard and Ground Motions Soil and hazard curve Ground motions (if needed) Structural Responses Option #1: Response-history Option #2: Simplified method Damage Prediction Contents (str. and non-str.) Fragility curves Loss Estimation (loss curves) and other consequences

11 FEMA P-58: Methodology 11 Hazard and Ground Motions Soil and hazard curve Ground motions (if needed) Structural Responses Option #1: Response-history Option #2: Simplified method Damage Prediction Contents (str. and non-str.) Fragility curves Loss Estimation (loss curves) and other consequences Monte Carlo Simulation used ( roll dice thousands of times). Each dice roll gives a single observation of losses (and other consequences). Putting all of the dice rolls together gives solid statistical information on performance.

12 FEMA P-58: Benefits 12 Objective process based on extensive test data and research. Quantitative performance information: Dig as deep as you like. Tools to communicate with owners. Solid statistical basis.

13 FEMA P-58: Perceived Difficulty 13 Hazard and Ground Motions Soil and hazard curve Ground motions (if needed) Structural Responses Option #1: Response-history Option #2: Simplified method Damage Prediction Contents (str. and non-str.) Fragility curves Loss Estimation (loss curves) and other consequences I need to hire a geotech to do this?!?! I need to do a response-history analysis?!?! I need to count and enter every foot of partition wall and other contents?!?!

14 FEMA P-58: Perceived Difficulty 14 It may not be as hard to implement FEMA P-58 as some currently perceive it to be. The What If Question: What if we had a stream-lined FEMA P-58 analysis that could be done in hours rather than days (and provide all of the same benefits)?

15 My Thinking Over Past Couple Years 15 Based on my discussions with practitioners, it looks like most of the barriers to FEMA P-58 use are related to software and ease-of-use. FEMA has funded additional development, currently working on both methodology advancements and design aids (to improve ease of use, etc.). FEMA and ATC have created a useful methodology but are not in the business of maintaining software. For our profession to move forward with use of FEMA P-58 methods, someone needs to step-up to provide/maintain user-friendly enabling software.

16 My Thinking Over Past Couple Years 16 In February, Jack Baker and I decided to work on filling this needed role by: a) Creating user-friendly software to implement P-58. b) Maintaining software over time (fragilities, etc.). c) Improving and extending the methodology in the future after ATC/FEMA work is done (improvements, extensions desired by SE s, etc.). Timing: Our timing lines up well with the USRC building rating system work, so we would like to help support this process.

17 Software Implementation of FEMA P Hazard and Ground Motions Soil and hazard curve Ground motions (if needed) Structural Responses Option #1: Response-history Option #2: Simplified method Damage Prediction Contents (str. and non-str.) Fragility curves Soil and hazard curves embedded. Simplified method embedded (only need period, mode shape, strength, yield drift). Structural and nonstructural contents estimated and prepopulated. Loss Estimation Two-level (loss structure: curves) (1) Simple (basic rating, prelim. design, PML) (2) Refine Presentation and go on as FEMA deep P-58 and as SP3 you like (full new PBD).

18 Status and Timeline 18 Status and Timeline: February: Started software work. April: Secured a National Science Foundation research commercialization grant for funding. Current: Active development (Jack, me, team of 7). November: Commercial Beta release. ATC/FEMA: Being done in coordination with ATC (so all pulling in same direction) but not funded by ATC (because needs to become a commercial tool to be sustainable).

19 Draft SP3 Tool 19

20 Next Steps 20 Our goal is to enable/support the use of newlyemerging tools like P-58 in our profession (both for ratings and for new performance-based design). We are still in active development, so please: Let us know how we can tailor SP3 to be most useful for our structural engineering profession. I would love to meet with you if you have advice! chaselton@csuchico.edu, curt@hbrisk.com Cell: (530)