【摘要】 强震动记录的使用通常不考虑观测方向对于水平地震动参数计算的影响。文中以2008年汶川Ms8.0级地震中绵竹清平台获取的强震动记录为研究对象,对记录进行水平向旋转以模拟观测方向的变化,分析水平向峰值加速度PGA、峰值速度PGV、相对持时DR、绝对持时DA及谱加速度PSA随观测方向的变化情况。结果表明,PGA、PGV及PSA的计算较大依赖于观测方向,而DR和DA则受观测方向影响较小。为此文中提出了一种与观测方向无关的水平地震动参数计算方法,对于计算诸如PGA、PGV等与周期无关的地震动参数时不考虑周期独立;而对于计算诸如PSA等与周期有关的地震动参数时考虑周期独立。更多还原

【Abstract】 For usage of strong-motion recordings,it is usually not considered the effect of observation-orientation on computing the parameters of horizontal ground motion.The strong motion recording obtained from Qingping Station in Mianzhu City of Ms8.0 Wenchuan Earthquake in 2008 are adopted.Two orthogonal horizontal acceleration time-histors are rotated in horizontal plane,and the variations of peak ground acceleration(PGA),peak ground velocity(PGV),relative duration(DR),absolute duration(DA) and pseudo spectra acceleration(PSA) with respect to different observation orientation are analyzed.The results show that PGA,PGV and PSA are highly dependent on observation-orientation,while DR and DA are independent.Therefore,a new method for computing the parameters of horizontal ground motion is suggested,which is orientation-independent.It includes two schemes that the one is for the period-independent parameters such as PGA,PGV and the other one is for the period-dependent parameters such as PSA.更多还原