Study On Static Performance Of Prestressed Concrete Composite Slabs With Precast Ribbed Panels

In this paper,the bending behavior of three different ribbed pre-stressed concrete composite slab(6 in total)and the shear properties of 16 pre-stressed concrete composite slabs were tested and numerically analyzed.The specific research contents are as follows:(1)The bending performance test of three different ribbed pre-stressed concrete composite slabs(6 in total)were completed,and the main parameters were ribbed form.According to the failure mode,load-displacement curve and load-strain curve of the ribbed form,the influence of the rib form on the bearing capacity and deformation performance of the test piece was analyzed.The test results show that the bearing capacity and deformation performance of the three ribbed pre-stressed concrete composite slabs are basically the same.(2)The finite element mode of the pre-stressed concrete composite slab was established based on ABAQUS software.The finite element results agree well with the experimental results,and the correctness of the finite element mode was verified.On this basis,the parameters of the pre-stressed concrete composite slabs were analyzed,and the influences of the concrete strength of the precast bottom panel,the reinforcement ratio of the prestressed wire,the span of the composite slab and the prestressing degree on the bearing capacity of the pre-stressed concrete composite slab were studied.Based on the results of the test and simulation,the calculation formula of cracking load and bearing capacity of precast composite slab was proposed.(3)The shear performance test of 16 composite slabs was completed.The main parameters were additional short steel bars and shear span ratio.According to the failure mode,load-displacement curve and load-strain curve of the specimen under different shear-to-span ratios,the effects of various parameters on the failure mode and shear capacity of the specimen were analyzed.The test results show that when the shear span ratio was 0.5 or 2,the failure mode and bearing capacity of the precast composite slab and the cast-in-place specimen were basically the same,the additional short steel bar has less influence on the shear capacity.When the shear-to-span ratio was 3,the longitudinal reinforcement ratio of the precast composite slab has a linear relationship with the bearing capacity.(4)Based on the experimental results,the shear behavior of the prestress composite slab under different shear-to-span ratios was theoretically analyzed.The mechanical model and simplified calculation formula of the precast composite at different shear-to-span ratios were proposed.When the shear span ratio is 0.5,the splitting failure model is adopted.When the shear-span-ratio is 2 or 3,the oblique section failure model is adopted.