| Steel bar truss composite type two-way slab under the push of housing industrialization, by the form of floor has the advantages of reasonable performance achieved larger promotion and has obtained certain social and economic benefits. Steel bar truss composite type two-way slab by flat-fell seam, the stress performance and through analyzing the integrity of the floor.There is no effective calculation method for bending moment and deflection for superimposed two-way floor because the floor seam weakens the cross-section stiffness. Using ABAQUS software, analysis model of superimposed two-way floor was established and variation rules of mid-span bending moment and deflection of superimposed two-way floor were studied according to the theory of elasticity. By using the method of quantitative calculation and qualitative analysis, mechanical conditions of the superimposed two-way floor were compared with that of the cast-in-place two-way floor with four edges simply supported. The results show that the stiffness in long side direction for superimposed two-way floor is reduced and flexural capacity in short side direction decreases; bending moment in short side direction for superimposed two-way floor increases, and bending moment value in long side direction is still reinforced according to cast-in-place two-way floor elasticity theory of reinforcement.; calculated results according to the elasticity theory, ABAQUS software simulation and experimental measured data agree well with each other, providing a reference for the research and engineering application of the same floor.Lattice steel truss based on the equivalent stiffness of truss theory into the research of equivalent steel, lattice steel truss composite floor increases the overall stiffness, in normal use phase, parallel to the X lattice steel truss composite floor than the ordinary superimposed floor across the maximum deflection decreases by about 8%, parallel to the Y lattice steel truss composite floor than the ordinary superimposed floor across the maximum deflection decreases by about 5%, load- deflection curve and anastomosed with the cast-in-situ two-way slab more basic indiscriminate force performance and ductility, lattice steel truss set up reasonable and effective. Parallel to the X lattice steel truss composite type two-way slab is parallel to the Y overall superior mechanical properties and the bending stiffness of the floor slab, but the difference is small, engineering design can ignore its influence.Defines the "vertical lattice steel truss composite type two-way slab", using the theory of equivalent analysis of the parallel to the parallel to the X and Y to the lattice steel truss composite type two-way slab load- accord well with those of the deflection curve of the deflection rate within 3%, 1% respectively, the basic can be ignored form different lattice steel truss composite floor the overall mechanical performance impact, three kinds of equivalent lattice steel truss composite floor slab and the deflection of cast-in-situ two-way slab in the normal use of phase change, flat-fell seam place have a certain amount of stress concentration of the floor slab, three types of lattice steel truss composite floor overall mechanical properties similar to site casting, can be used in engineering design.Coefficient of the plastic hinge line method limit load and increase short-term section flexural stiffness of reinforced composite type two-way slab theory is applied to the truss analysis, combining the theory of predecessors' research, studies and summarizes the seam and the seam reinforcement treatment method, the lattice steel truss layout vertical or parallel to the floor of the adjacent flat-fell seam to the impact of stress superposition type two-way slab theoretical Suggestions. The life and death of finite element software unit technology can be a very good simulation of the stress of the composite type two-way slab floor process, research and analysis of worth in the future in application. |
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