- See Section 2.274.
- Response parameter is pseudo-acceleration for 5% damping.
- Do not use pseudo-accelerations at periods > TMAX, the inverse of the lowest useable frequency in the
- Constant number of records to 1s, slight decrease at 2s and a rapid fall off in number of records for periods
- For long periods very few records for small earthquakes (M < 6.5) at any distance so magnitude scaling
at long periods poorly determined for small events.
- Choi and Stewart (2005) do not provide coefficients for site amplification for periods > 5s so linearly
extrapolate blin in terms of log period by assuming relative linear site amplification to decrease.
- To assign c3 for entire period range fit quadratic to c3s from four-event analysis with constraints for short
and long periods.
- No data from normal-faulting events for 10s so assume ratio of motions for normal and unspecified faults
is same as for 7.5s.
- Possible underprediction of long-period motions at large distances in deep basins.
- Chi-Chi data major controlling factor for predictions for periods > 5s even for small events.