Abstract:In order to seek a practical model to simulate coherence function of spatial ground motions for different types of sites, 1116 strong motion records of 35 strong earthquakes were collected from strong motion array databases of USA, Japan and China. The random vibration theory and the digital signal processing techniques were used to study the spatial ground motion coherency. By fitting the calculated spatial coherency function of horizontal ground motions and vertical ground motions, a practical spatial coherence model with unified mathematical expression for different sites was proposed and the corresponding parameters were analyzed. The results show that the coherence between two points of spatial ground motions has an exponential reduction tendency along with increasing distance and frequency. For different types of sites (bedrock, normal site and soft soil), the spatial coherency of soft soil site has the fastest attenuation, then is the normal site and the bedrock site has the slowest attenuation speed. The coherence function value is still noteworthy between two points with 20km distance and coherency of horizontal ground motions is more significant than that of vertical ground motions.
陈清军 杨永胜 王沿朝. 基于强震台阵记录的地震动空间相干函数实用模型[J]. 土木工程学报, 2016, 49(S1): 1-6.
Chen Qingjun Yang Yongsheng Wang Yanchao. A practical spatial coherence model of seismic ground motion based on strong earthquake array records. 土木工程学报, 2016, 49(S1): 1-6.