| Cast-in-situ RC hollow flat slab is a new kind of floor structure having circular holes made by hollow pipes. It has the advantage of lightness, large span, and good seismic behavior. It has been increasingly applied in engineering practice recently and has a promising market future. However, the research is only in a initiate stage, the complete theory of design has not been built, and the current method is only refer to the solid slab design process, or according to experience. So it is important problem to make a system study on cast-in-situ RC hollow flat slab and give some reasonable design suggestion.Firstly, experiment on RC hollow flat slab is carried out. The experimental model is 1:3 in scale and has a 3m×3m span. The experimental study is focused on the behaviors of RC hollow flat slab, including moment distribution, deformation, and the ultimate load-bearing capacity subjected to vertical uniform loads and lateral stiffness subjected to transversal loads.In this paper, finite element analysis program ANSYS is used for nonlinear analysis for RC hollow flat slab. The behaviors of RC hollow flat slab under different load-bearing stages are simulated, and the test results and theoretical analysis is verified.Based on elastic theory, in this paper cast-in-situ RC hollow flat slab is converted to orthotropic plates by the pseudo-plates theory and the equilibrium equation is built. In this paper, the formula of the hollow flat-plate's rigidity convert in two ways is deduced and the solution of the important parameter in the equilibrium equation is provoked.Based on the characteristic of the RC hollow flat slab, the traditional equivalent frame method is modified to fit RC hollow flat slab. Analysis and calculation method of equivalent frame-beam and equivalent frame-column is present. Flexural rigidity of plate is reduced because of circular holes in the plate made by hollow pipes. And it generates the change of moment distribution in the plate. The factors which impact moment distribution in the plate are analyzed in detail. The calculation method of moment distribution of RC hollow flat slab in the middle span subjected to vertical uniform loads is present.In this paper, the deflection formula of RC hollow flat slab in the middle span subjected to vertical uniform loads is provoked and the factors which impact deflection are analyzed. Based on the much calculate result of finite element, deflection coefficient of RC hollow flat slab is obtained by method of curve fitting. Lastly, Analysis on crack resistance capacity of RC hollow flat slab has been complete. And the formula of crack resistance capacity is present in this paper. As for the short-term deflection calculation of t RC hollow flat slab subjected to vertical uniform loads, an approximate method is presented. And the results give satisfactory agreement with the test records to verify the theoretical analysis.
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