Abstract：Four 1/3-scale high-strength lightweight aggregate concrete (HSLAC) interior beam-column joints with respect to two levels of axial compressive forces and joint stirrup ratios were prepared and tested under the reversed quasi-static cyclic loading. The shear performance, including the failure modes and failure processes, hysteretic curves and skeleton curves, stiffness and strength degradations, displacement ductility, energy dissipation, and the stirrup strains, were systematically studied. The failure characteristics and the shear strengths of these specimens and the discrepancies with normal weight concrete (NWC) specimens were mainly analyzed. Test results indicate that, similar to NWC specimens, all HSLAC specimens may experience four phases, namely, initial cracking, running-through cracking, ultimate phase and failure phase during the entire failure process. In terms of the hysteretic curves and the displacement laws of joint, the specimens are almost the same as the NWC specimens. In terms of the energy dissipation and the ductility, the specimens are close to the NWC specimens. The failures of HSLAC specimens may occur at the aggregate boundary and across the aggregate, and during the failure concrete, peeling off in a large area, cutting off of some aggregates in the concrete cover and the entire spalling of concrete can be seen. Properly increasing the axial compression ratio and the transverse reinforcement ratio can effectively enhance the shear strength and improve the ductility and energy dissipation properties of joints. Due to the increased strength of lightweight aggregates, the bond property between HSLAC and longitudinal bars within joint core can also be improved to some extent. Only a few of stirrup may yield. Hence, it is recommended that the composite stirrup or confined concrete shall be used to enhance the confinement. Additionally, calculation results indicate that, under the condition without reducing the HSLAC strength, the predicted results from the shear models are in good agreement with the test results, and appropriate increase of the HSLAC strength reduction factors for various shear models is suggested.
吴涛 刘喜 魏慧. 高强轻骨料混凝土框架中节点抗震性能试验研究[J]. 土木工程学报, 2018, 51(6): 32-42.
Wu Tao Liu Xi Wei Hui. Experimental study on seismic behavior of frame interior joints with high-strength lightweight aggregate reinforced concrete. 土木工程学报, 2018, 51(6): 32-42.
