Affecting aspects on the behaviour of frame joints

Abstract

The variation of reinforcement details, confinement and joints angle are considerable factors which affect the ultimate limit moment of joints and joints efficiency. The variation of joint size is another factor that significantly affects the ultimate limit moment of joints and frame joints efficiency. These previous factors were not considered in design. Corners may be subjected to closing moments, which subject to tensile stresses in the outside of the corner, or to opening moments, which cause tensile stresses in the inside of the corner. The last type of moments arise more detailing problems. Opening joints may be found in retaining walls water tanks, open channels, bridge abutments, high rises due to wind effect, frame structures, etc. in the other hand the closing joint may be found in two hinged and fixed frames and underground water tanks. Hence two types of joints should be compared.The presented paper introduces an experimental and analytical study in order to investigate the effect of reinforcement details, confinement, joints size, joints angle on the frame joints efficiency and comparison between closing joints and opening joints. Experimentally, a total of eleven specimens were tested under vertical load. All specimens were tested up to failure and the behaviour was fully monitored. Moreover, a nonlinear 3D-finite element analysis was established using ABAQUS program and verified with the experimental results in order to give design recommendations for those structural elements.