Earthquake responses of clusters of building structures caused by a near-field thrust fault

A numerical simulation method with structures, earth medium and finite-fault sources being considered together is presented for studying responses of building structures to the near-fault earthquake. The multi-degree-of-freedom models are adopted for the structures and the finite-fault model is applied for the causative fault. Investigated lumps of different type are considered to establish the dynamic equilibrium equations for the structures, the earth medium and the connections between them, respectively. The algorithms and the stability conditions have been derived for wave propagations in the structures and the earth medium, respectively. The investigated lumps considered for the connections are used to implement the two-way wave propagations between the structures and the earth medium. The earthquake responses of three clusters of 6-story frame structures, which respectively located on the hanging wall, rupture forward and footwall, are studied during the fault rupture. The inter-story drifts and dynamic deformations of frame structures, and the wave fields in earth medium excited by the vibrating structures show remarkably different characteristics for the structures located on different places. In addition, the structures of different type consisting of 24-story and 6-story frames are also studied. It shows that the high-rise structures influence greatly the neighboring multi-story structures located on the hanging wall and rupture forward of the fault.

► An integrated method is presented.
► Structures, earth media and finite fault can be considered together in the method.
► Two-way wave propagation between structures and earth medium is implemented.
► The method can be used to study the earthquake responses of structure clusters.
► The method is helpful for drawing up land-using plan in the earthquake-prone cities.