Peak horizontal acceleration and velocity from strong-motion records including records from the 1979 imperial valley, California, earthquake

摘要: We have taken advantage of the recent increase in strong-motion data at close distances to derive new attenuation relations for peak horizontal acceleration and velocity. This analysis uses a magnitude-independent shape, based on geometrical spreading anelastic attenuation, curve. An innovation technique is introduced that decouples determination distance dependence from magnitude dependence. The resulting equations are log A = − 1.02 + 0.249 M r 0.00255 0.26 P ( d 2 7.3 ) 1 / 5.0 ≦ 7.7 V 0.67 0.489 0.00256 0.17 S 0.22 4.0 5.3 7.4 where g , velocity cm/ sec, moment magnitude, closest surface projection fault rupture km, takes value zero rock sites one soil sites, 50 percentile values 84 values. We considered magnitude-dependent but we find no basis it data; adopted shape because requires fewer parameters.