Interface Shear Strength Of Composite Slab

Concrete composite slab is one of the most widely used composite structures, the interface shear strength has a great influence on the ultimate bearing capacity of composite slab.Firstly, a theoretical research on the interface shear strength of steel truss concrete composite slab is conducted and the interface cohesive model is adopted to simulate interface shear strength. By analyzing the cohesion model parameters, the damages evolution character of concrete interface are captured. A modified equation of the steel truss concrete composite slab interface shear strength is put forward, considering the influences of bent reinforcement at interface.Secondly, based on the concrete shear strength under pure shearing, shear strength of concrete dowel on the precast slab is calculated. Combined with the bond-slip constitutive relationships of the interfaces between the precast and cast-in-place slabs, and the shear capacity calculating model of prestressed concrete composite slabs with ribs is established.Finally, A Finite Element Method (FEM) analysis on steel truss composite slabs and the prestressed concrete composite slabs are carried out. The concrete damage constitutive model and bond-slip interface model are adopted to simulated, the damage intiation and evolution of the composite slab is simulated. Comparing with the theoretical analysis, the simulating results could be used to modify the shear strength model parameters.In conduction, the biomaterial interface bond-slip model could adopted for the analysis of shear strength steel truss concrete composite slabs and prestressed concrete composite slabs with ribs, and thereby evaluates the deformation and energy release rate at interface, which reflects the interface failure process. This method can be applicated in composite slabs design.