Plastic Hinge Zone Effect on Seismic Evaluation of RC Frame under Iraqi Seismic Code Loading

The engineers have been using a nonlinear static procedure or pushover analysis due to its simplicity. Pushover analysis is a useful technique to assess how a structure performs when subjected to earthquake loads. The plastic deformation is located in a small zone, namely the plastic hinge zone. A significant design parameter is the length of the plastic hinge region, where intense containment should be given to increase the member's ductility for safety from severe events such as earthquakes. This work tries to investigate the effect of plastic hinge length on the performance points for two-dimensional reinforced concrete frames. Plastic hinge length is adopted by considering Park and Paulay besides Priestley hinge length formulations. The results conducted that that base shear capacity does not depend on the plastic hinge length for two equations of plastic hinge length, while the results show that the increase of the displacement capacity of Paulay equation was 87.72% and 10.05% higher than Priestly equation for 4- and 7 stories respectively. The results also show that the two expressions don’t affect the performance level by generating the elastic response spectrum according to the updated Iraqi seismic code-2017.