Totally 113 groups of horizontal ground motion were selected from the Wenchuan rnearthquake to study the influence of fault strike on honzontal ground motion. Differences between faultrnnormal (FN) and fault-parallel ( FP) components were researched by comparing the peak ground rnacceleration, duration, response spectra, amplification factor and characteristic period. The research rnresults show that when fault distance is less than 50 km, peak ground acceleration of the FN component rnis larger than that of the FP component, and the mean ratio of their peak ground accelerations is rnslightly affected by site conditions; durations of the two components both increase with the fault rndistance. When the fault distance is less than 100 km, the difference of their durations under site rnclass Ⅰ is larger than that under site class Ⅱ. In near-fault areas, the mean ratio of their response rnspectra is larger than that of their amplification factors, and the differences of their response spectra rnand amplification factors are more obvious under site class Ⅰ than under site class Ⅱ ; characteristic rnperiods of the two components show a sufficient difference, and site conditions have a large effect on rnthe mean ratio and difference of their characteristic periods.%为探讨断层走向对水平地震动的影响,选取汶川地震113组水平地面运动加速度记录,对比研究了垂直断层方向(FN)和平行断层方向(FP)分量的地震动加速度峰值、持时、反应谱、放大系数和特征周期等参数的差异.结果表明:断层距小于50 km时,FN分量地震动加速度峰值大于FP分量,且二者加速度峰值比的均值受场地条件影响较小;断层距越大,FN和FP分量地震动加速度持时越长;断层距小于100 km时,Ⅰ类场地FN和FP分量加速度持时的差别大于Ⅱ类场地;近断层区域内,FN与FP分量加速度反应谱比值的均值大于放大系数比值的均值,Ⅰ类场地FN和FP分量加速度反应谱、放大系数的差别均分别大于Ⅱ类场地;FN和FP分量地震动特征周期差别明显,且二者比值的均值和差值的均值都受场地条件影响较大.
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