2016年10月20日江苏射阳M4.4地震的强震动记录分析

Strong Motion Records from the Sheyang M4.4 Earthquake on October 20,2016

对2016年10月20日江苏射阳M4.4地震的强震动记录进行初步分析,介绍强震动记录的一些基本特征。与ShakMap小震回归公式的预测数据比较,发现实际观测值总体高于预测值。通过对强震动记录的反应谱分析,认为本次地震对震中区建筑的影响轻微。在地震动等值线图产出过程中,采用数据偏差校正、场地效应及空间插值方法,使地震动等值线图的空间表达更为合理。其等值线图长轴呈北西向,与此次地震的主破裂面方向一致。结合地震现场调查结果,讨论了震中区的烈度分布与仪器烈度。

The characteristics of the strong motion records of the Sheyang M4.4 earthquake that occurred on October 20,2016 in Jiangsu Province were analyzed.Comparing the data predicted by using the ShakMap regression formula with the actual observed data revealed that the actual observed data were higher than the predicted data.Analyzing the acceleration response spectra of strong motion records showed that the earthquake exerted negligible effects on buildings in the epicentral area.The methods of data bias correction,site effect analysis,and spatial interpolation were used to draw the contour map of ground motions.This multimethod approach enhanced the rationality of the spatial expression of the contour map.Finally,intensity distribution and instrumental intensity in the epicentral area were discussed in combination with the results of field survey and damage assessment.