The Mechanical Performance Study Of Reinforced Concrete Flat Slabs With Openings

As a widely used modern structure, Flat slabs with openings can be seen in practical construction and reconstruction of building existing with more requirement for function. This paper deals with the mechanical performance of flat slabs with openings which have been few studies on this topic.On the basis of finite element software ANSYS, a flat-slab model of 4 spans and 16 lattices is made. Paralleling calculating result with the one counted by the classical elastic slabs theories proves the reliability of this model. By the aid of finite procedure this paper analyses the effect of the opening shape, dimension and location on the flat slabs mechanical behavior in detail. Then interrelated coefficient is given to help to calculate the maximum stress on the slab with opening.This paper also puts emphasis on the regular flat slabs with openings in the center bearing the lateral uniform load for the convenience in practical engineering design. The static bending moment is calculated after making the flat slabs with openings equivalent to a continuous beam based on the same bending capacity. Then yield line theory is used to get the ultimate resistance of a slab with opening. A simplified calculation formula of each slab belt is given after detailed deduction.Large data calculating result and contrast analysis prove the integer mechanical behavior of flat slabs have not been changed by the openings, no matter what the opening shape dimension and location are. Except the mechanical performance of slab with opening has been changed the stress on the rest slabs distribute as straps distinctly. So as a whole structure, the flat slabs can be calculated by traditional experimental coefficient or equivalent frame.