International Journal of Civil & Structural Engineering
Author(s) : HUSSEIN M. ELSANADEDY, MOHAMMED A. ALRUBAIDI
The recent terrorist attacks around the world have prompted the respective authorities to address the risks to the critical infrastructure. Precast construction has become increasingly common in the Kingdom of Saudi Arabia because of its speed, which is extremely desirable due the current high rate of development in the Kingdom. In general, buildings are extremely vulnerable to progressive collapse if some of the columns are lost due to blast exposure. As precast buildings lack structural continuity and redundancies in the load paths, they are even more susceptible to progressive collapse than cast-in-situ monolithic buildings. Thus, to avoid catastrophic events, it is important to study the likelihood of the progressive collapse of precast structures in the Kingdom. In this study, the behavior of two different half-scale precast specimens were studied experimentally under middle column removal scenario. These specimens were designed to represent the most common types of exiting precast beam-column connections in the Kingdom of Saudi Arabia. Precast specimens were prepared with beam and column members cast individually and then assembled on test bed as is the norm in the field. One monolithic specimen, which was designed with continuous top and bottom beam reinforcement, was used as a baseline for comparison with the two precast specimens. For the three test specimens, the column removal scenario was simulated by releasing the support of the middle column and applying a high-rate loading, which involved the displacement of the test column at a rate of 100 mm/s to failure. Behavior of different specimens was evaluated and compared on the basis of test results in terms of mode of failure and load-displacement characteristics. Test results reveal that the ultimate load carrying capacity and ductility of precast specimens are much less than that of the monolithic one. The two tested types of precast connections were found to have a very high potential of progressive collapse.