Modeling of Cyclic Behavior of Retrofitted Beam-Column Joint
Ali H. Al-Gadhib, Mohammed H. Baluchi, عبد السميع محمد عبدالهادي حلاحله
كلية الهندسة-جامعة الملك فهد للبترول والمعادن · السعودية
Reinforced Concrete (RC) moment resisting frame structures are commonly used for lateral load resisting systems. However, such structures have often suffered damages caused by earthquakes, including permanent damage and/or failure where Beam-Column Joints (BCJs) have been identified as the weakest link in such systems. If BCJs could regain their original shape and strength with a minimum repair after an earthquake then the problems associated with permanent damage could be mitigated. Also, in a seismically active area of Saudi Arabia, prior to 1990’s, most of the BCJs were constructed with seismic detailing with no shear reinforcement in the joint. This could result in the failure of these joints in the case of a seismic event.The objectives of this research, entitled “Modeling of Cyclic Behavior of Retrofitted Beam-Column Joint” were to investigate the behavior of BCJs under cyclic loadings for two scenarios: (1) Non-retrofitted normal reinforced concrete beam column joints, (2) CFRP wrapped externally around the existing RC BCJs for the purpose of retrofitting. Three types of Beam-Column Joints specimens were tested with different detailing reinforcement and retrofitted with CFRP sheet wrapped around the joint. A numerical modeling of joints with and without CFRP were also conducted by using finite element analysis software (ABAQUS) which helped to interpret the monitored behavior of BCJs through comparison with the numerical simulation and mechanistic models. The ABAQUS finite element software has the ability to model the nonlinear response of reinforced concrete member using Elasto-plastic-damage theory which simulates the cyclic and monotonic loading behavior of BCJs. These Beam-Column Joints are representative of existing detailed building in seismically active areas of Saudi Arabia.