LINEAR STATIC ANALYSIS OF MASONRY INFILLED R.C.FRAME WITH &WITHOUT OPENING INCLUDING OPEN GROUND STOREY
Masonry infill walls are mainly used to increase initial stiffness and strength of reinforced concrete (RC) frame buildings .It is mainly considered as a non-structural element. In many cities of India, it is very common to leave the first storey of masonry infilled reinforcement concrete (RC) frame building open preliminary to generate parking space or any other purposes (Ex-Reception lobbies) in the first storey. This Open First storey is also termed as “Soft Storey”. The upper storeys have brick infilled wall panels with various opening percentage in it. This type of buildings are highly undesirable in seismically active areas because various vertical irregularities are created in such buildings which have consistently performed very poor behavior during past earthquake. In the present study, it is attempt to access the performance of masonry infilled reinforced concrete (RC) frames with open first storey of with and without opening. In this paper, symmetrical frame of college building (G+5) located in seismic zone-III is considered by modeling of initial frame. With reference to FEMA-273, & ATC-40 which contain the provisions of calculation of stiffness of infilled frames by modeling infill as a “Equivalent diagonal strut method”. Therefore, the infill panels are modeled as a equivalent diagonal strut method. This linear static analysis is to be carried out on the models such as bare frame, strut frame, strut frame with centre &corner opening, which is performed by using computer software STAAD-PRO from which different parameters are computed. In which it shows that infill panels increase the stiffness of the structure. While the increase in the opening percentage leads to a decrease on the lateral stiffness of infilled frame.