Study of Behavior & Strengthening of Beam-Column Joint

Abstract

The beam column joint is the crucial zone in a reinforced concrete moment resisting frame. It is subjected to large forces during severe ground shaking and its behavior has a significant influence on the response of the structure. One of the most important factors affecting the successful strengthening technique of structures is the selection of the strengthening material. The need to lower the cost of maintenance, repair and strengthening techniques, while extending the service life of the structures, has resulted in new systems, processes, or products to save money and time. The objective of this paper is to study and gathering information about the beam-column joint, its structural behavior under seismic conditions, forces acting, types, factors those influences the designing criteria, bond and transverse reinforcement requirements and effective rehabilitation schemes for reinforced concrete beam-column joints thus providing a contribution to a more reliable evaluation of the seismic vulnerability of Reinforced Concrete buildings. Different fiber-wrap rehabilitation schemes are apply to the joint panel with the objective of upgrading the shear strength of the joint. In order to obtain local and global ductility, a series of structural details are required in the seismic design, generally absent or inadequate in the existing RC buildings designed without seismic rules. A reliable evaluation of the seismic performance is particularly needed on these buildings, as a fundamental tool in order to select type, technique, extent and urgency of the strengthening intervention. Many are the factors influencing the structural performances of RC buildings, among them an important role is carried on by the ultimate capacity of the beam-column joints. Some authors performed experimental investigations both on reduced and real scale beam-column sub assemblages to better understand their behavior, also for the development and calibration of software models to be used in non-linear analysis of framed RC structures.