冷弯薄壁型钢-混凝土组合楼盖受弯承载力影响因素分析

Influencing factors analysis on flexural capacity of cold-formed steel joists concrete composite floor

采用ANSYS非线性有限元分析方法,分析了压型钢板与钢梁连接螺钉间距、钢材屈服强度、混凝土强度、C型钢梁板厚、钢筋混凝土翼板厚度、压型钢板型号、钢梁间距、楼盖宽度、钢梁跨高比及腹板高厚比等因素对冷弯薄壁型钢-混凝土组合楼盖受弯承载力和延性的影响。研究表明:压型钢板与钢梁连接螺钉间距、钢材强度、钢梁板厚、压型钢板型号、钢梁间距、楼盖宽度、钢梁跨高比和腹板高厚比等因素对组合楼盖受弯承载力影响较显著,而混凝土强度则影响较小;钢筋混凝土翼板厚度在50～100 mm范围内时,组合楼盖受弯承载力随混凝土翼板厚度增加呈线性增长,当翼板厚度大于100 mm后,其受弯承载力将不再提高;混凝土强度、钢梁间距及楼盖宽度不影响组合楼盖的延性。组合楼盖可简化为T形截面组合梁模型计算。

Using nonlinear finite element analysis method with ANSYS, and changing the spacing among the screws connecting the profiled steel sheet and the steel joists, yield strength of steel, strength of concrete, thickness of C type steel joists, thickness of concrete slab, types of profiled steel sheet, space between steel joists, width of floor, span- depth ratio of steel joists and height to thickness ratio of the web, the flexural capacity and the ductility of composite floor were researched. The research shows, the effects of the spacing among the screws connecting the profiled steel sheet and the steel joists, yield strength of steel, thickness of C type steel joists, types of profiled steel sheet, spacing between steel joists, width of floor, span-depth ratio of steel joists, height to thickness ratio of the web on the flexual capacity of composite floor are remarkable. The strength of concrete has little influence. The flexural capacity of composite floor increases linearly as the thickness of concrete slab changs from 50 mm to 100 mm, and no further improvement can be obtained wben the concrete slab is thicker than 100 mm. The strength of concrete, spacing between steel joists and width of floor have little influence on the ductility of composite floor. T-shaped section composite beam model can be used as the simplified calculation model of the composite floor.