Numerical Modelling of Joint Shear Capacity for Non-Ductile RC Structures: A Comparative Study

Abstract

Beam-column joints play a key role in ensuring the structural integrity of building subject to seismic forces, particularly older-type reinforced concrete structures. Lack of proper detailing of the joint panel of such systems tends to increase its shear deformation, thus making it highly flexible. For this reason, it is important to develop models that will be able to accurately predict the shear strength capacities of beam-column joints, which in turn can be used in simulation studies of buildings under earthquake loading. Two joint shear strength models, by Bakir and Bodurog (2002) and by Hassan (2011) were evaluated using three beam-column joint sub-assemblages. These assemblages were formulated in the non-linear finite element program, where a zero-length rotational spring was introduced at the joint to induce the joint flexibility. A constitutive model that admits in-cycle strength and stiffness degradation, and having highly pinched hysteretic loops, is used to simulate the experiment responses. Results obtained from Hassan (2011) model corroborated with the experimental results with accuracies lying between 98% to 92%. The model by Bakir and Bodurog (2002) produced accuracies between 92% to 82% as compared to the experimental results. Drift ratios however were not accurately predicted.