Seismic Response of a Periodic Array of Structures

A simplified two-dimensional model of the dynamic interaction, through the soil, among adjacent structures in a densely built area is presented. The model consists of an infinite number of identical parallel infinitely long shear walls placed on equally spaced rigid semi-cylindrical foundations. The steady-state response of the shear walls to obliquely incident plane SH waves is evaluated and compared with the response of an isolated structure. The results obtained indicate that the presence of adjacent structures has a significant effect on the seismic response, particularly, at low frequencies and in the vicinity of the Rayleigh frequencies for the array. For high frequencies, only the immediately adjacent structures affect the response of the central shear wall.