Seismic response of masonry buildings with sliding substructure

In spite of poor record of safety of masonry buildings during past earthquakes, it continues to be the most common method of building construction. A building system, is considered here to investigate the ground motion isolation feasibility, in which a clear smoothened surface is created at plinth level and is free to slide except for the frictional resistance. The sliding arrangement introduces an isolation effect and reduces the energy input by dissipating part of the seismic energy through friction. The seismic response of the masonry buildings with sliding substructure subjected to Koyna and El Centro shocks is computed through a two mass-spring-dashpot mathematical model assuming the frictional resistance as rigid plastic. The parameters involved in the analysis are time period, mass ratio, and coefficient of friction. The spectral quantities of the sliding system are plotted against the natural period for various mass ratio and coefficient of friction. These spectra show the reduction in response of the buildings with sliding arrangement as compared with the conventional buildings.