ANALYSIS OF STEEL FRAMES WITH BRACINGS FOR SEISMIC LOADS

In recent decants steel structure had played an important role in construction industry. Providing strength, stability, ductility for buildings designed for seismic loads. It is necessary to design a structure that can withstand under seismic loads. Providing steel knee braces is one of the structural systems used to resist earthquake forces on structures. Steel bracing is economical, easy to erect and occupies less space which is flexible to design to meet the required strength and stiffness. There are various types of steel bracing (X, knee bracing). In knee brace frame system (KBFS) the non-buckling diagonal bracing provide most of the lateral stiffness, the flexural yielding of knee element. In our project a 6 storey steel frame building with knee bracing system with floor plan of 9 m x 9m is considered. We studied the performance of a 6 storied steel frame building with knee bracing system and compared with bare frame. Pushover analysis, equivalent static analysis, Response Spectrum analysis, Time history analysis is performed in ETABS based on IS 1893:2002 (part 1) guidelines. The manual calculation was done on the basis of Equivalent static analysis and Response spectrum analysis to find out base shear for foundation and lateral force for each storey deck slab and compared the values with bare frame. Depending on the complexity in the problem for bracing models, we had used Etabs software in order to analysis the Base shear and lateral shear.