汶川地震峰值加速度多圆组合模型的衰减关系

Wenchuan earthquake peak acceleration attenuation relationship of multiple circle model

考虑近场理论地震图的合成和大震地震动模拟过程,提出多圆组合的地震动衰减关系模型。以汶川地震震害较为严重7省的地震峰值加速度记录为分析对象,分别回归出圆模型、断层破裂模型及多圆组合模型的衰减关系。结果表明:多圆组合模型和断层破裂模型对于汶川地震动峰值加速度的模拟相对于圆模型更加理想;大震近场地震动的饱和现象在地震动衰减关系的分析中是不能被忽视的。

Considering the composition of earthquake map in near site and simulation of ground motions for major earthquake, a multiple circle model was proposed. Taking the records from 7 provinces affected severely in Wenchuan earthquake three models respectively, including the circle model, the fault-rupture model, and the multiple circle model. The result shows that the accuracy of multiple circle model and fault-rupture model is more ideal than circle model for simulating peak ground acceleration （PGA） of Wenchuan earthquake and that saturation of ground motion in near site can not be ignored.