不同拼接方式下大跨度钢筋混凝土叠合楼板力学性能分析

Analysis of Mechanical Properties of Long-Span Reinforced Concrete Composite Slabs with Different Joint Methods

基于某装配式建筑项目中的大跨度楼板,运用ABAQUS模拟该楼板分别采用整跨现浇楼板和不同拼接方式的双向叠合楼板情况下楼板的力学性能和破坏形式,结果表明:现浇楼板整体性优于叠合楼板,但平行拼接双向叠合楼板力学性能与现浇楼板相差不大;中间跨叠合楼板现浇拼缝处易出现应力集中而最先开裂,且随着楼面均布荷载的增大,裂缝会越过后浇拼缝向边跨叠合板发展,最终楼板板底混凝土全部开裂失效;大跨度楼板若采用桁架钢筋叠合楼板,应采用双向叠合楼板,且现浇拼缝宜布置在受力较小的方向,不宜双向布置。

Based on a certain prefabricated building project with large-span floor slabs,ABAQUS was employed to simulate the mechanical performance and failure modes of the floor slabs under two scenarios:cast-in-place slabs and two-way overlapping slabs with different joint methods.The results indicated that cast-in-place slabs exhibit better overall performance than overlapping slabs,but the parallel-joint two-way overlapping slabs have almost the same mechanical properties to cast-in-place slabs.In the case of overlapping slabs in the middle span,stress concentration and initial cracking are prone to occur at the joint of the cast-in-place section.As the uniformly distributed floor load increases,cracks may extend beyond the joint and progress towards the edge of the overlapping slab,ultimately leading to complete cracking and failure of the concrete at the bottom of the slab.For large-span floor slabs using truss-reinforced overlapping slabs,it is recommended to choose two-way overlapping slabs,and the cast-in-place joints should be placed in the direction with lower stress,avoiding a bidirectional arrangement.