基于增量动力分析的重力-侧力承载体系分离钢木混合结构抗震性能研究

Seismic performance of steel-timber hybrid structures with separated gravity and lateral resisting systems based on incremental dynamic analysis

为充分发挥钢木材料及钢木结构受力性能的优势,提出一种重力-侧力承载体系分离的钢木混合结构。通过可变形连接降低结构在地震作用下的响应。以钢板剪力墙-胶合木框架混合结构为例,对钢、木结构之间的连接参数设计范围进行确定,进而基于增量动力分析研究钢木混合结构在各性能水准地震作用下的最大层间位移角,并通过概率地震需求分析方法对结构的损伤指标进行评估。结果表明:在重力-侧力承载体系分离钢木混合结构中,通过可变形连接可降低连接内力和结构楼层加速度,结构在立即居住、生命安全和防止倒塌性能水准下的层间位移角限值建议分别取为0.2%、0.7%和2.6%;地面峰值加速度与结构最大层间位移角之间总体呈对数线性关系,结构在浅表地震作用下的最大层间位移角比在深层地震作用下更大;重力-侧力承载体系分离钢木混合结构的抗震性能良好,各性能水准下的最大层间位移角超越概率较低。

Steel-timber hybrid structures with separated gravity and lateral resisting systems were proposed in this paper to take full advantage of the mechanical properties of steel and timber materials and substructures.The introduction of deformable connections reduces the seismic structural response.Taking the steel plate shear wall-glulam frame hybrid structures as an example,an approximate feasible parameter design space for the deformable connection between steel and timber structure was defined.Furthermore,the maximum inter-story drift ratios of the structure under different seismic hazard levels were determined based on incremental dynamic analysis,and the damage indices were assessed by probabilistic seismic demand analysis.The results show that the introduction of deformable connections in steel-timber hybrid structures with separated gravity and lateral resisting systems can reduce the internal force of connections and the floor acceleration of glulam structures.The limit states of maximum inter-story drift ratio under immediate occupancy,life safety,and collapse prevention are 0.2%,0.7%,and 2.6%,respectively.Besides,a log-linear relationship between the peak ground acceleration and the maximum inter-story drift ratio is observed,and the maximum inter-story drift ratio under shallow earthquakes was larger than that under deep earthquakes.The seismic performance of steel-timber hybrid structures with separated gravity and lateral resisting systems is satisfactory,with a low maximum inter-story drift ratio exceedance at each performance level.