模块化装配式斜支撑节点钢框架试验研究

为了获得模块化装配式斜支撑节点钢框架结构中框架体系的受力性能、破坏模式及破坏机理,对4个原尺寸的一层两跨单榀框架进行了水平和竖向静力加载试验,研究了装配式斜支撑节点钢框架的承载能力、变形特性、传力机理、破坏形态和机理.通过不同斜撑布置和构件截面尺寸框架的受力性能对比分析,获得了影响其极限承载能力的规律.进行了4个一层两跨单榀框架的实体非线性有限元静力分析,并与试验结果对比.研究结果表明:装配式斜支撑节点钢框架抗侧刚度大,延性性能较好,抵抗水平荷载能力强;结构塑性变形均发生在桁架梁和斜支撑上,符合“强柱弱梁”的抗震设计原则;斜撑对抵抗水平荷载和变形至关重要;与桁架梁交汇处是斜支撑受力薄弱的区域,斜支撑槽形截面开口处最先屈服,但屈服后塑性变形没有进一步发展,斜支撑槽形截面的腹板受力较小.

Model Test of Modularized Prefabricated Steel Frame With Lean-brace Joint

To get the mechanical characteristics, failure mode and mechanism, the horizontal and vertical loading tests were performed on 4 full-size one-layer and two-span frames. Its mechanical characteristics, load-bearing capacity, deformation characteristics, failure model and mechanics were studied in the paper. The influence regulation of ultimate bearing capacity was obtained by contrasting analysis with frames having different thickness of components and different layout of lean braces. The finite element models of 4 full-size frames were analyzed, and the results were compared with those of model tests. Results show that the prefabricated steel frames have large lateral stiffness, good ductility, strong ability to resist horizontal load. And plastic deformations only occur on the truss beams and lean braces, which meets the seismic design principle of “strong column and weak beam”. The lean braces play significant roles for resisting horizontal loads and deformation. The junction area between lean brace and truss beam is the weak area, and the top point on flange of channel's cross section of lean brace yields firstly, but the plastic strain does not further develop, and the stress on the web of the cross section is relatively small.