钢筋桁架混凝土叠合楼板试验及有限元分析

Experimental research and finite element analysis of concrete composite floor slabs with steel bar trusses

通过对钢筋桁架混凝土叠合楼板施工阶段和正常使用阶段受力性能的试验研究,发现板在施工阶段的性能是否满足规范要求由其短期刚度控制,而非由其承载力控制;预制层与叠合层之间的叠合面抗剪性能无需进行验算。若预制板在施工阶段的短期刚度满足规范要求,则叠合板在使用阶段的刚度和承载力均会有较高的安全储备。在试验研究的基础上,利用非线性软件ANSYS对试验板进行了建模分析,之后对影响预制板短期刚度的主要因素的数值分析表明:钢筋桁架的高度、间距及上下弦杆的直径对预制板短期刚度的影响比较明显,腹杆直径的变化对板受力几乎没有影响,设计中只需满足构造要求、保证上弦钢筋受压稳定即可。

Mechanical behaviors of concrete composite floor slabs with steel bar trusses under construction and use stage analyzed by the test. Result shows that whether the performance of floor slabs meet specification requirements controlled by short-term stiffness of precast slab, rather than bearing capacity. Shear strength checking of bond-interface of slab is unnecessary. If short-term stiffness of precast slabs meet specification requirements under construction, the stiffness and bearing capacity of composite slabs will have a lot of margin in serviceability stage. Furthermore, nonlinear finite element software ANSYS was applied on validation and parameters analysis which shows that truss＇s spacing and height, diameters of top and bottom chords, has a significant influence on the short-term stiffness of the composite floor slabs under construction. Change of web member diameter has no influence on mechanical performance of slabs, design needs to meet the detailing requirements under construction, as long as meets requirements of stability of upper chords.