Structural Behaviour of Steel Building with Diagonal and Chevron Braced CBF (Concentrically Braced Frames) by Pushover Analysis

This paper presents diagonal and chevron braced steel structure design with pushover analysis conducted following ATC-40 guidelines. In this study, the lateral load used is increased gradually until plastic hinge and collapse occur. The results are capacity curve, performance point, and the process of plastic hinge until the building collapse. There are five steel structure models designed based on the various types of bracing and bracing configuration. Model 1 is steel structure without bracing, model 2 and 3 are chevron braced steel structure, model 4 and 5 are diagonal braced steel structure. The results of this study indicate that the performance level of five models structure for earthquake in x direction and y direction according to ATC-40 is IO (Immediate Occupancy). Model 4 has the best effectiveness in terms of plastic hinge mechanism compared to other models. In the last step, model 4 is able to reduce plastic hinge 84% from model 1 for earthquake in x direction and 79% from model 1 for earthquake in y direction. Model 3 has the greatest ability to carry the forces of an earthquake compared to other models. It is 185% bigger than model 1 for x direction and 181% bigger than model 1for y direction. Model 3 has the greatest effectiveness in reducing lateral displacements compared to other models in the amount of 65.47% of model 1 for x direction and 72.14% of model 1 for y direction. Model 3 has the greatest effectiveness in reducing storey drift compared to other models in the amount of 73.89% of model 1 for x direction and 80.55% of model 1 for y direction.