Analytical Analysis of Seismic Behaviour of Precast Structure

Precast concrete systems represent an efficient alternative for building construction. The behaviour of a precast system depends on connections and it should be modeled properly in the computational models for analysis and design. The connections between precast members normally constitute the weakest link in the structure, and the satisfactory performance and economy of precast concrete structures depend to a great extent on the proper selection and design of the connections. Due to inadequate guidelines most designers assume the beam-column connection as perfectly hinged connection which leads to unexpected behaviour of the structure. In this paper an attempt is made to resolve this problem by considering the connection as semi-rigid i.e. the actual behavior of connection is modeled discretely to allow limited rotation at the joint. The beam-column connection is allowed with an amount of rotation in accordance with experimental work presented in research papers. The complex behavior of beam-column sub-assembly is counteracted using frame elements with linear links. A 4-storey building is modeled with in SAP2000 and compared with the monolithic building for linear static and dynamic analysis. The models are subjected various earthquake Time Histories i.e. Bhuj, Parkfield, and El Centro so as to cover all the parameters. The results of Top Displacement, Base Shear and Storey Drift are compared for the four models. It concludes that the Top displacement and Storey Drift increases whereas Base Shear decreases for precast building as compared to monolithic RCC structure.