采用抑制屈曲支撑的钢框架结构性能分析

Performance of steel frame installed with buckling-restrained braces

为了对比分析抑制屈曲支撑与普通钢支撑构件在反复荷载作用下的滞回性能,比较了2种支撑钢框架体系在单调、往复水平荷载和地震荷载作用下的抗侧力和抗震性能.基于ANSYS对结构构件和体系进行了分析,并与试验结果进行了对比.分析表明,抑制屈曲支撑可在拉压循环荷载作用下均达到屈服,拉压承载力基本一致,恢复力模型可简化为对称的双线型,其滞回曲线稳定饱满,滞回耗能能力大大优于普通钢支撑.同时数值分析结果与试验结果也得到了很好的吻合.抑制屈曲支撑相对于普通钢支撑可进一步提高钢框架结构的后期刚度、极限承载力和耗散能力,更大地降低了结构的地震响应,提高了结构的抗震性能.因此抑制屈曲支撑较普通钢支撑更适于在有更高抗侧力和抗震要求的钢结构中应用,其更为简单的恢复力模型也使结构体系的分析和设计十分简便.

The hysteretic behavior of buckling-restrained brace （BRB） and conventional brace under cyclic load, the performance of the steel frame with BRBs or conventional steel brace under monotonic, cyclic horizontal load and seismic load were analyzed based on ANSYS. The results were compared with experimental results. The results indicate that BRB can undergo fully-reversed axial yield cycles without loss of stiffness and strength. BRB is confirmed to have nearly the same yielding stress and ultimate strength under tension and compression, whose superior seismic energy dissipation ability is better than the conventional steel brace. The symmetrical bilinear resilience model of BRB is confirmed. The results of numerical analysis based on ANSYS agree well with experiments. Compared with conventional steel braces, when BRBs are applied into steel frame, the intensified stiffness, strength and energy dissipation ability of the steel frames will be improved. Compared with the steel frame structures with conventional steel braces, the seismic responses （displacement, acceleration, force） of the steel frame structures with BRBs are greatly reduced and seismic performance is improved. Therefore BRB with simple bilinear resilience is adapted to apply in structures with more requirement to resist horizontal and seismic load. It makes the analysis and design of structures more convenient.