古建木构枓栱侧向刚度的试验研究

通过对典型枓栱的模型的低周反复荷载试验,研究了枓栱侧向刚度的退化规律.试验得出枓栱的力-位移滞回曲线及骨架曲线,并拟合出了力-位移的关系方程和枓栱恢复力模型,由试验结果给出枓栱侧向刚度的线性变化.通过试验得出以下主要结论:枓栱以水平滑移变形为主,并通过摩擦滑移起到耗能、隔振的效果;枓栱的滞回曲线呈平行四边形,形状饱满外包络面积大,说明枓栱具有良好的滞回耗能特性;枓栱的力学模型属于线性强化弹塑性模型.恢复力模型反应了枓栱恢复力特性及刚度变化规律,适应于同类木结构的静力传递和结构动力分析计算研究.研究结果为古建筑的抗震性能研究和修缮加固提供了理论基础.

Experimental research on the lateral stiffness of ancient wooden Dougong

Experiment on the typical model of Dougong was carried out under low cyclic reversed loading to study the lateral stiffness degradation law of Dougong. Force-displacement hysteretic loops and skeleton curves of Dougong were obtained to fit out the force-displacement equation and resilience model of Dougong. Energy dissipation caused by frictional slippage is an important reason for the excellent seismic behavior of cuch ancient wooden structure. Hysteretic loops of Dougong assume to be of the parallelogram-type. Experiment agrees with theoretic analysis and the plump area of hysteretic loop accounts for its excellent energy dissipation performance. The mechanic model of Dougong belongs to linear strengthened elastic-plastic model. Both the fitting equation of force-displacement and resilience model reflect the changes in stiffness of Dougong, and adapt to the research on static load delivery as well as dynamic structural analysis and calculation of similar wooden structure. This provides a theoretical basis for the study on the seismic performance, remedy and strengthening of ancient wooden structures. The result of test provides a theoretical basis for seismic performance studying and reinforcement repairing for Chinese historic buildings.