1. 2020 NEHRP Provisions Issues Ground Motion
C. B. Crouse
2016 BSSC Colloquium

2. Multiperiod response spectra Deterministic caps?
Ground-Motion Issues
Multiperiod response spectra
Deterministic caps?
Physics-based models (numerical simulations)
Fault-rupture directivity & 3-D basins
Site coefficients (Fa, Fv, FPGA) for CEUS
Vertical component (Ch. 11.9)
Induced seismicity?
Soil-structure interaction – Ch. 19
Provisions for foundations on piles
Footing-soil modeling & design
Relax some restrictions

3. New Approach for Computing Long Period Sa
Use Ground Motions from 3-D Numerical Models to Develop Long Period Sa Maps
Application: L.A., SEA, SFO, SLC
ASCE 7-22 Standard

4. Model Regional 3-D Effects on Long Period Motions
a(t)
Basin
Fault
Rock

5. Southern California Earthquake Center
Utilization of Ground Motion Simulations Committee (SCEC UGMS)
Goal: develop GM maps for L.A. region
UGMS Committee formed in 2013; meets twice/yr
SCEC performs calculations under UGMS direction

6. Los Angeles Sites

7. LAPD MCER

8. PAS MCER

9. COO MCER

10. Los Angeles Sites

11. CPP MCER

12. COO MCER

13. Intermediate Goal of UGMS
MCER maps for L. A. City
Amendment to ASCE 7-16 maps for City
Resource to City and consultants
Look-up tool ~ USGS web app tool