Mid-column seismic pounding of reinforced concrete buildings in a row considering effects of soil

Seismic pounding between adjacent non-identical buildings may occur during earthquakes, if the separation between them is insufficient. This paper deals with the seismic pounding between three typical reinforced concrete moment resisting frame buildings in a row, where a 10-story building is located between two identical 9-story buildings, considering the effects of underlying soil on the structural response. The story height of 10-story building is different from those of the two 9-story buildings and this gives rise to mid-column pounding. A finite element analysis software SAP2000 is used to analyze the buildings. The structural components including foundations of the buildings are designed to fulfill the code requirements of ACI 318-02 and IBC 2003. The underlying soil is taken into account through the discrete model at the foundation level and the contacts between the buildings are incorporated through impact elements consisting of a gap element and a Kelvin-Voigt element. Two far-field earthquakes and two near-field earthquakes are used as input motions to investigate the response of buildings. Interstory displacements, impact forces and normalized story shear are computed to evaluate the performance of the buildings. In general, the results of analyses show that the interstory displacements, impact forces and normalized story shear are reduced when underlying soil is considered.