@ ŒfÚŽGŽi˜ajF “ú–{’nkHŠwƒVƒ“ƒ|ƒWƒEƒ€u‰‰W VolF 5Šª ”NF 1978”N •ÅF 33-40•Å ’˜ŽÒi˜ajF - ƒ^ƒCƒgƒ‹i˜ajF - ´˜^i˜ajF
- ƒL[ƒ[ƒhi˜ajF - ŒfÚŽGŽi‰pjF PROCEEDINGS OF JAPAN EARTHQUAKE ENGINEERING SYMPOSIUM ’˜ŽÒi‰pjF F. K. Chang, E. L. Krinitzsky ƒ^ƒCƒgƒ‹i‰pjF EFFECTS OF MAGNITUDE, DISTANCE, AND SITE CONDITIONS ON DURATION OF STRONG EARTHQUAKE MOTIONS ´˜^i‰pjF
The observed spread in the frequency content of strong-motion accelerograms does not vary greatly with duration, magnitude, and site geological conditions though there is a predominance of low frequencies (<2 Hz) at alluvial sites. Maximum bracketed durations (>0.05 g) appear to be greater in soil sites than in rock sites by a factor of at least 2 to 1. A decrease in bracketed duration with distance from source is very pronounced for soil sites in the near field. Resonance can greatly increase the duration of shaking, particularly in soft alluvium. ƒL[ƒ[ƒhi‰pjF - ‹LŽ–‹æ•ªF - ‹æ•ª @@@ˆÏˆõ‰ï˜_•¶W