Analysis of RC Frames Using Different Bracing Systems in Different Positions and Zones

Abstract

Structures are mainly built to enhance the performance of several activities like recreation, transportation, power generation, etc. They are built to sustain the loads coming on them during their service life by carrying adequate strength and also limit the deformation by possessing enough stiffness. Strength of a structure depends mainly upon the characteristics of material with which it is constructed. Stiffness is dependent upon the cross-sectional and geometrical properties of the structure. Earthquake damage depends upon a lot of parameters including intensity, duration, frequency content of ground motion, geologic and soil condition, quality of construction, etc. Structure design must be as such as to ensure that the structure has satisfactory or acceptable strength, high ductility and will remain as one unit, even while subjected or undergo a very large deformation. Steel bracing is a highly efficient and economical method of resisting horizontal forces in a frame structure. Steel bracing system enhances the resistance of the structure against the horizontal forces by expanding its stiffness and stability. Bracing holds the structure stable by exchanging the horizontal loads for example, quake or wind burdens down to the ground and oppose the side-long loads, in that way keep influence of the structure. The use of steel bracing systems for strengthening or retrofitting seismically inadequate reinforced concrete frames is a viable solution for enhancing the earthquake resistance. Bracing has been used to balance laterally for the majority of the world’s tallest building frames as well as one of the major retrofit measures. Bracing is effective because of the diagonal work in axial stress and therefore call for minimum member sizes in providing rigidity and strength against horizontal shear. Through the addition of the bracing system, load could be transferred out of the frame and into the braces, by-passing the weak columns while increasing the strength. Steel braced frames are efficient, structural systems for buildings subjected to the earthquake or wind lateral loadings (loads due to earthquake, wind, blast, fire hazards, etc.). The intention of this study is therefore used to investigate the effect of position of bracing systems in earthquake performance by equaling it with the bracing systems at different positions and without bracing systems. This is performed in this study work, by carrying out a comprehensive literature survey and analysis of multi-story (G+13) buildings for various earthquake zones with different geometries.
Keywords: Earthquake force, bracing system, position, shear, moments, displacement