Analysis of Mechanical Properties of Long-span Reinforced Concrete Composite Slabs under Different Splicing Methods

Based on the long-span slab in an assembled building project, ABAQUS is used to simulate the mechanical properties and failure modes of the slab under the condition of the whole span cast-in-place slab and the two-way rebar truss composite slab (hereinafter referred to as composite slab) with different splicing methods, in which the slabs adopt fixed support and the slab loads are uniformly distributed load. The finite element simulation results show that the integrity and mechanical properties of the whole span cast-in-place slab are not different from those of the parallel splicing two-way composite slab, but they are obviously better than the parallel cross splicing two-way composite slab; In the same slab span, the cast-in-place seam of the composite slab in the middle cracks first due to stress concentration, and with the increase of the uniformly distributed load of the slab, the crack will pass through the cast-in-place seam and develop to the composite slab on both sides, and finally all the concrete at the bottom of the slab will crack and fail. According to the simulation results, the following suggestions are given: if the truss rebar composite slab is adopted for the long-span slab, the two-way composite slab should be adopted, and the cast-in-place seam should be arranged in the direction of less stress, and the seam should not be arranged in both directions.