Experimental Study on Precast Beam Column Connections Constructed Using RC Corbel and Steel Billet under Progressive Collapse Scenario

Abstract

Progressive collapse denotes a failure of a major portion of a structure that has been initiated by failure of a relatively small part of the structure such as failure of any vertical load carrying element (typical ly columns). Failure of large part of any structure will results in to substantial lo ss of human lives and natural resources. Therefore, it is important to prevent pr ogressive collapse which is also known as disproportionate collapse. Now a days, ther e is increasing trend towards construction of buildings using precast concrete. In precast concrete construction, all the components of structures are produced in controlled environment and they are being connected appropriately at si te. Connections are the most critical elements of any precast structure, because in past major collapse of precast structure took place because of connection failure. In this study , behavior of four different reduced 1/3 rd scaled precast specimens having wet and dry connections is investigated under column removal scenario and their perf ormance is compared with monolithic connection. Precast specimens considered for the study are constructed by adopting different detailing having column with RC corbel and column with steel billet for connection with precast beam. Performance of specimen is evaluated on the basis of ultimate load carrying capacity, maximum deflection and deflec tion measured along the span of the beam. From the results, be tter performance of precast connections is observed up to elastic phase but later on st rength of dry precast connections degrades more as compared to monolithic conne ction. Wet precast connections exhibit superior performance as compared to monolithic connection, which advocates replacement of monolithic connection with appropriate connection detailing. From the results, is also observed that preca st connections constructed using RC corbel performs better as compared to thos e constructed using steel billet.