Research On Mechanical Properties Of The Steel Bar Truss Concrete And Superimposed Precast Slab

As a new style floor slab,the steel bar truss concrete and superimposed slab combined with the advantages of precast slab and cast-in-place slab,not only have a high speed of construction,but also have high stiffness and earthquake-resistance properties.The new style floor slab has already been widely used in our country because it shows good mechanical properties.Most of the research about steel-bar truss concrete and superimposed slab focus on the mechanical properties,stiffness research,joint splicing of the whole composite slab at present.However,the research about precast slab is not sufficient.Therefore,the research about mechanical properties of the precast slab in this paper,in order to provide theoretical basis for the construction of the superimposed slab.It has a positive effect on the promote of the superimposed slab.The bending behavior of one prefabricated slab,one prefabricated slab which cut the top steel-bar-truss and one steel-bar truss concrete and superimposed slab was researched by testing in this paper.The data about performance of three slabs in different period was obtained and the result shows steel-bar-truss can reduce the deflection of the slab during construction stage,improve the anti-cracking performance and stiffness of slab.Static non-linear simulation on the slabs by ABAQUS,compare the calculated results with the experimental results.Then analyzed the influence of four factors on the bending stiffness of the precast slab,including the concrete strength,the diameter of the top chord and bottom chord,the diameter of the web bar steel and the number of steel bar truss.Finally,research the relationship between the number of steel bar truss and temporary support by finite element model.Using equivalent second axial moment of area to deduct stiffness formula of the precast slab based on the relevant specification and literature.Then,compared the calculated stiffness values with the test values to verify the accuracy of the formula.Finally,summarize the content and defect of this paper,put forward the prospect and suggestion of the follow-up research.