冷弯薄壁型钢轻质混凝土组合墙体抗震性能试验研究

Experimental Study on Seismic Performance of Cold-Formed Thin-Walled Steel-Concrete Composite Wall

摘要: 本文提出了冷弯薄壁型钢轻质混凝土组合墙体，该墙体以冷弯薄壁型钢形成的钢骨架作为主要受力构件，外侧固定水泥板或钢网模等免拆模板，其间浇筑混凝土。考虑了组合墙体浇筑不同种类的轻质混凝土(分别为筑粒混凝土和聚苯颗粒混凝土)、型钢骨架是否设置斜撑两种因素，对4个组合墙体进行低周反复加载试验，分析了组合墙体的受力过程和破坏模式，并对组合墙体的滞回性能、骨架曲线、延性、刚度退化等抗震性能指标进行研究。试验结果表明：4个组合墙体的主要破坏形式基本相同，在控制位移较小时，墙体只在角部出现细小裂缝，随着位移的增大，表面的轻质混凝土在沿型钢布置方向处出现细小裂缝，并逐渐沿此方向延伸，直至贯通，最后型钢屈曲，墙体破坏。使用筑粒混凝土和设置斜撑均可以提高组合墙体的抗震性能，但若单独考虑这两种因素时，使用筑粒混凝土对抗震性能的提高效果要好于设置斜撑。

Abstract: In this paper, a cold-bent thin-walled steel lightweight concrete composite wall is proposed. The wall is made of a steel frame formed by cold-bent thin-walled steel as the main force-bearing member, and a free-form template such as a cement board or a steel mesh form is fixed on the outside, and concrete is poured in between. Considering the combination of pouring different types of lightweight concrete (pollterm concrete and polystyrene granulated concrete) and whether the steel frame is provided with braces, the four combined walls were repeatedly tested in low cycles and analyzed. The stress process and failure mode of the combined wall, and the seismic performance indicators such as hysteretic performance, skeleton curve, ductility, and rigidity degradation of the combined wall are studied. The test results show that the main failure forms of the four composite walls are basically the same. When the control displacement is small, the wall only has small cracks in the corners. As the displacement increases, the small cracks gradually appear along the direction of the steel layout, and slowly extend in this direction until it penetrates, and finally the steel buckles and the wall is destroyed. The use of granulated concrete and the installation of diagonal braces can improve the seismic performance of the composite wall, but if these two factors are considered separately, the improvement effect of the use of pollterm concrete on the seismic performance is better than the installation of diagonal braces.