来源:《建筑结构学报》2023 年第 8 期
作者:彭志明,陈忠范,徐志峰,黄宇浩
出处:《建筑结构学报》2023
摘要
冷弯薄壁型钢组合墙体是装配式轻钢结构住宅的主要抗侧力构件,传统湿法现场浇筑施工效率偏低。本文针对 3 组采用不同干法装配连接的冷弯薄壁型钢‑泡沫混凝土组合墙体开展低周往复拟静力试验,对比不同连接构造下墙体的破坏模式、承载能力、刚度退化与耗能能力。试验结果表明:合理设计的干法装配连接构造可以实现 “构件先于节点破坏” 的抗震设计目标;对比传统现浇墙体,干法装配墙体承载力略有下降,但变形能力与耗能性能表现更优;对拉式连接方案综合性能最优,可为冷弯薄壁型钢装配式墙体工程应用提供试验依据。
Abstract
Cold‑formed thin‑walled steel foam concrete composite wall is the main lateral‑resistant component of prefabricated light‑steel residential buildings. Traditional cast‑in‑place construction has low site efficiency. In this paper, quasi‑static cyclic loading tests were carried out on three groups of composite walls with different dry assembly connections. Failure mode, bearing capacity, stiffness degradation and energy dissipation capacity were compared. The test results show that reasonably designed dry connections can realize the seismic target of “component failure prior to joint failure”. Compared with cast‑in‑place walls, dry‑assembled walls show slightly lower bearing capacity but better deformation and energy‑dissipation performance. The tension‑pull connection scheme has the best comprehensive performance, which can provide reference for engineering practice of cold‑formed thin‑wall steel assembled walls。
(一)墙体试件设计与加载方案
设计 3 片足尺冷弯薄壁型钢‑泡沫混凝土组合墙体试件,分别采用不同干法装配连接构造;采用水平低周往复加载方式,观测墙体裂缝开展、局部屈曲现象,获取承载力、刚度、滞回耗能等关键指标。
(二)不同连接构造抗震性能对比
对比三种连接形式的破坏特征:部分构造出现连接件过早撕裂;优化后的对拉连接试件,墙体内部泡沫混凝土先出现斜向交叉裂缝,龙骨发生局部屈曲,连接节点保持完好,实现构件先破坏。
装配干法墙体初始刚度略低于现浇墙体,但延性系数更高,滞回环更加饱满。
(三)参数影响分析
分析墙板厚度、龙骨间距、连接件间距对墙体抗剪承载力的影响;增大连接件数量可以提升节点刚度,但会增加现场安装工作量,需要平衡抗震性能与施工效率。