中文摘要：

基于在大跨网架结构中的应用，对目前的三重钢管防屈曲耗能支撑进行改进，设计了一种新型支撑，并对该支撑考虑初始缺陷下的力学性能进行了理论分析。根据理论分析，设计了四组不同的支撑，利用ABAQUS有限元软件模拟分析了在拉压循环荷载作用下支撑强度比对其力学性能的影响，包括连接段应力状态、滞回耗能能力和核心管屈曲破坏模式。研究结果表明：该新型耗能支撑结构布置可行，设计方法合理，强度比是影响支撑力学性能的重要参数，在强度比合理范围内，支撑具有良好的滞回耗能性能；在轴向循环荷载作用下，内外套管约束作用明显，核心管破坏模式为多波小幅屈曲破坏，变形稳定，满足防屈曲支撑设计要求。

英文摘要：

Based on the application of long-span space truss structures, a new type of triple-steel tube buckling-restrained brace was proposed by improving and redesigning current triple-steel tube buckling-restrained braces. The mechanical properties of the brace were analyzed in consideration of initial imperfection. According to this analysis, 4 groups of braces were designed and the effect of strength ratio on the mechanical properties, including the stress state of connection parts, hysteretic behavior, and the failure mode of the core tube, were studied under tension-compression cyclic loading using the ABAQUS software. It is shown that the new structure configuration is feasible and the design method is reasonable. Strength ratio is the key parameter affecting the mechanical properties, and within a reasonable range, the hysteretic performance is well. Under the axial cyclic loading, the effect of inner and outer bushing constraints is obvious, the failure mode of the core tube is multiple-wave small buckling, and the deformation is stably. So the new triple steel tube buckling-restrained brace meets the requirements of design.