Investigation the effects of HPFRCC materials on the robustness of RC frames subjected to progressive collapse

Reinforced Concrete (RC) Frames cover a large part of our country's structures. Neglect progressive collapse in this type of structures can lead to significant human and financial costs. Most of the regulations related to RC frames have comprehensive measures for resistance to seismic forces but there are only a few general solutions to increase the robustness to progressive collapse have been provided. In this study the effects of using High Performance Fiber Reinforced Cementitious Composite materials (HPFRCC) in the beam-column joints and the effects of its use on the robustness of RC frames against progressive collapse have been evaluated. For this purpose, after verifying the simulations with experimental tests using Opensees software the robustness of two 10-story RC frames under progressive collapse has been evaluated. The performance of the samples was measured using the robustness index proposed by Fascetti et al. The Fascetti robustness index is a combination of nonlinear dynamic and nonlinear static analyzes that evaluate the structural robustness to progressive collapse under multi columns removing scenario. The results of the sample analysis show the use of HPFRCCs materials in the joints beam-column can dramatically improve the robustness of concrete frames against progressive collapse by increasing the stiffness and ductility of the beam-column joints.