Abstract:
Confinement introduces deformability in reinforced concrete structural elements. The stress–strain relationship of confined concrete is significantly influenced by the yield strength, configuration and spacing of the confining reinforcement. Performance of confined reinforced concrete components can be studied through their load-displacement response curves. Parameters such as yield, peak load, ultimate displacement, stiffness degradation and ductility can all be measured and evaluated from these curves. The hinge zones of beam and columns, in reinforced concrete frames, are often well confined. However, higher ductility requirements of the system can only be met if the stress path of moment reversals occurring at the face of supports exists through the joint. The joints are often congested. An interior joint, of intermediate floor, is required to accommodate reinforcement of at least six structural components. Due to congestion it is difficult to add confining reinforcement in the joints. In this project, a proposed technique to confine beam-column joints using steel strips will be implemented and examined. The technique uses contact area of steel strips to provide confinement and economize on the overall volume of confining reinforcement provided in the joints. The behavior of steel-strip-confined beam-column joints will be studied in the form of load-displacement curves. The experimentally achieved curves will be modelled in some appropriate FEM tool through simple calibration. The response of joints confined with steel strips will be compared with those confined by stirrups and FRP. The comparison will be used to quantify the effect of proposed confining reinforcement. The study will be helpful in understanding the response of beam-column joints. The calibrated models of steel strip confined and stirrup confined beam-column joints will be available for further application in evaluation of the performance of building structures. Such analysis will be helpful to estimate the improvement in the response building structures containing joints confined by proposed technique.
The idea here is to explore whether the proposed confinement gives better results or at par results, in either case considerable amount of steel is saved in quantity and henceforth the introduction of new confinement technique in the market will be proposed basing on results.
