地震地表破裂发育特点及环境条件分析

FEATURES AND CIRCUMSTANCES FOR SURFACE SEISMIC RUPTURES

通过已有震害实例分析,总结出了地震地表破裂的发育特点,在此基础上,结合震源破裂的深、浅部环境条件和形成力学机制、震源破裂和地震地表破裂的相互关系,讨论了地震地表破裂形成的环境条件。认为其所处的地震地质区特点是影响地震地表破裂发育的宏观环境条件,而场地第四系松散地层是影响地震地表破裂发育的微观环境条件。第四系地层对地震地表破裂的影响主要取决于第四系地层的土动力学性状、不均匀性和土层厚度等因素。

By analyzing some seismic damage examples, the features of surface seismic ruptures are summarized. Combining with focal rupture circumstances, mechanisms and the relations of focal and surface seismic ruptures, the circumstances for surface seismic ruptures are discussed. It is considered that the seismogeological condition is the most important factor for influencing the generation of surface seismic ruptures, but the Quaternary layers act as another important role in the arising for seismic rupture at the surface. The main influencing factors of Quaternary layers contain the dynamic indexes of layers, uneven distributions of layers and the layers thickness.