带支撑胶合木框架抗震性能试验研究

针对胶合木框架侧向位移不易满足抗震要求这一问题,研究了增设人字形胶合木支撑和铝合金屈曲约束支撑的带支撑胶合木框架的抗震性能。对纯胶合木梁柱框架和3个增设支撑胶合木框架进行了低周反复加载试验,分析了4个胶合木框架试件的水平承载力、耗能能力、刚度退化、转角变形和木支撑应变。结果表明:增设人字形木支撑和铝合金屈曲约束支撑均可以显著提高胶合木框架的承载力、耗能能力和刚度;支撑端部连接形式对胶合木框架的抗震性能有一定影响;增设支撑的3个胶合木框架试件均在支撑或支撑连接处发生破坏,胶合木框架主体并未发生明显损伤,两类支撑均很好地起到了第一道抗震防线的作用,保证了主体框架的安全。胶合木框架数值模拟和木支撑截面尺寸参数分析结果表明,经柱截面尺寸修正后的有限元模型针对框架抗侧刚度和承载力具有较好的预测精度。

Experimental study on seismic behavior of braced glulam frames

Glulam post-and-beam structures are difficult to meet the requirement on lateral displacement under seismic aotions. In order to solve this problem, the seismic behaviors of three K-braced glulam frames were studied, two of which were using glulam braces and one of which was using buckling restrained braces (BRB) made by aluminum alloy. The four specimens were tested under reversed low-cyclic loading, and the lateral carrying capacity, energy dissipation capacity, stiffness degradation, rotation, and strains of glulam braces were analyzed. Test results show that frames with K-brace and aluminum BRB exhibit higher lateral carrying capacity, energy dissipation capacity and stiffness. The effect of connection details at each end of the braces on the seismic behavior of the braced frames should not be ignored. The failure of the braced frames is caused by the failure of connections or braces, while no obvious damage of glulam beams and columns can be observed. This means these two types of braces can withstand earthquake firstly and ensure safety of the main frame. Finite element analysis was conducted to simulate the seismic behavior of the glulam frames, and parameter analysis of the cross section of the glulam brace was carried out. Numerical results show that the corrected finite element model has good accuracy in predicting the lateral stiffness and carrying capacity of the frames.