Study On Mechanical Properties Of Reinforced Concrete Composite Slab With Joint

Reinforced concrete composite slab meets the requirements of building industrialization and building integration in China,has a wide range of application prospects,and has been actively promoted in the domestic and foreign markets.Separated joint is adopted for reinforced concrete composite floor with joint,Compared with the integral lap joint structure,this method can effectively save the formwork,reduce the construction process and greatly shorten the construction period,Because the reinforcement of the bottom slab is not fully involved in the stress,the stiffness of the traditional split joint composite plate is weak in the vertical direction of the joint,and the bearing capacity is not strong,In this paper,a kind of joint structure is proposed,which can effectively enhance the integrity and bearing capacity of composite plates.In this paper,the mechanical properties of reinforced concrete composite plates with joints are studied,the corresponding elastic design method is proposed,and the calculation method of ultimate bending capacity of reinforced concrete composite plates with joints is studied.The work of this paper is as follows:1.In this paper,five separate one-way spliced laminated plates with the same size and different joint structures are tested and studied,and five one-way plates are analyzed from the aspects of deflection,reinforcement strain,cracks between the side and the bottom of the plate,rigidity and bearing capacity,from which an optimal joint structure is selected,and its performance indexes are superior to those of other plates.At the same time,the rigidity of five laminated plates is analyzed And get its short-term bending stiffness.2.Using the large-scale finite element analysis software ABAQUS,five one-way slabs are simulated under the same size and reinforcement,and compared with the test results,it is found that the finite element and test results are in good.agreement;on this basis,the finite element model of prestressed two-way composite slab is established,and the parameters such as deflection,stress and strain of the finite element model are carried out the analysis,It is concluded that it has obvious two-way stress characteristics.3.Based on the theory of orthotropic plates and trigonometric series,the elastic design method of prestressed concrete composite plates with joints is studied,and the tables of elastic design coefficients of bending moment and deflection under various boundary conditions are derived for the designer’s reference.4.Based on the theory of plastic hinge line,the ultimate flexural capacity of prestressed concrete composite slab with joint is calculated and compared with the results of finite element simulation.On this basis,the flexural capacity of various boundary conditions is calculated.Different structures are used to calculate the vertical seam direction,and the results are compared,it is found that the simulation value of finite element is in good agreement with the theoretical value.