钢-木屈曲约束支撑增强胶合木框架抗侧性能试验研究

为研究屈曲约束支撑增强胶合木框架的抗侧性能，制作了四榀胶合木框架试件，包括一榀纯木框架、一榀胶合木支撑增强木框架以及两榀碳纤维布缠绕钢-木屈曲约束支撑增强木框架。通过水平低周反复荷载试验，对木框架的损伤模式、滞回曲线、骨架曲线、刚度退化和耗能能力进行了研究，并研究了屈曲约束支撑刚度对木框架抗侧性能的影响。结果表明：侧向力作用下胶合木支撑发生平面外失稳的脆性破坏，屈曲约束支撑除端部钢板平面外弯曲外无明显损坏；胶合木支撑和屈曲约束支撑均能显著增强木框架的抗侧刚度和抗侧承载力，但相对纯木框架，胶合木支撑增强木框架位移延性系数降低了22.5%，屈曲约束支撑增强木框架位移延性系数增加约41.6%；屈曲约束支撑增强木框架刚度退化明显，但其有效刚度始终大于其他木框架；屈曲约束支撑增强木框架的总耗能约为胶合木支撑增强木框架的228%。提高约束屈曲支撑的刚度能够进一步提升木框架的抗侧性能。

Experimental study on lateral performance of glulam timber frames with timber-steel buckling-restrained bracings

To investigate the lateral performance of glulam timber frames with buckling-restrained bracings, four glulam timber frame specimens, including a simple frame, a frame with glulam timber bracings and two frames with CFRP-wrapped timber-steel buckling-restrained bracings, were fabricated and tested under lateral reversed cyclic loading. The failure modes, hysteretic and skeleton curves, stiffness degradation and energy dissipation capacity of the test specimens were studied, and the influence of the stiffness of the buckling-restrained bracings on the lateral performance of timber frames was also studied. The experimental results indicate that the timber bracings have a brittle failure mode of out-plane buckling, whereas noticeable damage is not found on the buckling-restrained bracings except that their end steel plates are bent in the out-plane direction. Both timber bracings and buckling-restrained bracings significantly improve the lateral stiffness and peak loads of the glulam timber frames. However, compared to the simple frame, the ductility coefficient of the timber braced frame is decreased by 22.5%, while the ductility coefficient of the frames with buckling-restrained bracings is increased by 41.6%. Serious stiffness degradation is found for the frame with buckling-restrained bracings, but its effective stiffness is greater than other frame specimens. The total energy dissipated by the frame with buckling-restrained bracings is 228% of that of the timber braced frame. The lateral capacity of frames can be further improved by increasing the stiffness of timber-steel buckling-restrained bracings.