钢框外敷混凝土和石膏板复合墙体受压性能试验

Experiment on compression performance of steel frame composite wall sheathed with concrete and plasterboard

摘要:

为了提升传统冷弯薄壁型钢组合墙体的装配效率和防护性能,提出一种钢框外敷混凝土和石膏板复合墙体（简称“复合墙体”）,骨架为槽型截面外边框加冷弯薄壁C型钢立柱,外墙板为带有钢筋网的现浇混凝土面层,内侧用石膏板敷面,中间填充保温隔热材料。对4片复合墙体的受压性能进行了试验研究,考察混凝土面层、洞口尺寸和位置对墙体承载力的影响,得到了不同构造墙体在竖向荷载作用下的破坏形态。建立有限元分析模型,对影响墙体受力性能的因素进行分析,包含混凝土面层厚度、配筋率、内覆板材料、墙板螺钉间距、面层混凝土和钢框材料强度、洞口尺寸。研究结果表明:带混凝土面板的墙体竖向承载力比不带混凝土面板的墙体有较大程度的提升,门窗洞口对墙体的承载力影响较大,墙体的破坏是墙体内侧立柱首先局部屈曲,引起墙体沿着各墙柱屈曲部位的连线向内侧失稳；混凝土面层配筋率、墙板类型和螺钉间距对复合墙体竖向承载力影响较小,建议钢筋网间距取50 mm,石膏板采用150 mm螺钉间距。

Abstract:

In order to improve the assembly efficiency and protection performance of traditional cold-formed thin-walled steel composite wall, a steel frame composite wall sheathed with concrete and plasterboard (referred to as “composite wall”) was proposed, where the main skeleton consists of channel-shaped beams framed with cold-formed thin-walled C-steel column, the external wall is cast-in-place concrete panel reinforced with steel mesh, the inner side is covered with plasterboard, and the thermal insulation material is filled inside between the external and internal panels. Four composite walls were tested, and the compression behavior of the walls was studied. The effects of concrete panel and the size and positions of the opening on the bearing capacity of the walls were investigated. The failure modes of walls with different configurations under vertical load were identified. A finite element analysis model of the wall was established, and the factors affecting the structural performance of the wall were analyzed, including the thickness of the concrete panel, the steel reinforcement ratio, the type of inner wallboard, the screw spacing of the wallboard, the strengths of both concrete and steel sections, and the size of the opening. Research results show that compared with the wall which has no external concrete panel, the wall with concrete panel possessed higher vertical bearing capacity, and the openings in the wall such as door and window had greater impact on the bearing capacity of the composite wall. The failure of the wall began with the local buckling of the column on the inner side of the wall, causing the wall to lose stability to the inner side along the connecting line of the buckling parts of each wall column. The reinforcement ratio of concrete panel, the type of wallboard, and the screw spacing had little influence on the vertical bearing capacity of the composite wall. It is suggested that the spacing of steel mesh should be 50 mm and the distance of screws of plasterboard should be 150 mm.