The Effect of Application of High Performance Fiber Reinforced Cementitious Composites (HPFRCC) on the Cyclical Behavior Improvement of Reinforced Concrete Beam-Column Connections

According to recent studies, beam-column connections in concrete structures are highly important since failure in these parts, as the main elements of force transmission in the building, causes the destruction and instability of the entire structure. The use of high performance fiber reinforced cementitious composites (HPFRCC) is one of the new methods to make beam-column connections. These materials include cement mortar with fine aggregates and fiber. They have high pre-failure cracking and energy absorption capabilities due to exhibiting strain hardening behavior under tensile loading, which can lead to the formation of structures with higher resistance and ductility than the conventional concrete structures. In this paper, following the introduction of HPFRCC materials, the impact of using HPFRCC materials on improving the beam-column connection performance was studied. To this end, the results of experimental studies by Chao at the University of Michigan were used as the basis for verification of finite element model. Accordingly, the effects of different connection parameters on the connection performance were examined in the base model individually or in combination. The results of nonlinear finite element models analysis indicated that the ductility ratio of HC-B0-C711.2 and HC-B0-C355.6 models is higher than other models. Thus, their ductility ratio appears to be 50.1% higher than the base connection. In addition, the maximum resistance of the HC-BS50 connection is greater than all other models so that its maximum resistance is 4.6 % more than the base connection.