Flat slabs - locally supported slabs are an important and preferred type of modern buildings structures. The column – slab contact point has the concentration of compression but especially shear and tensile stresses which may cause sudden failure – punching of slabs. The paper deals with the analysis of flat slab sample with two openings near the column - the typical example of real structures. The results are presented only for one size and location of openings. Material properties for analysis were obtained from experimental work carried out at the Department of Concrete Structures at STU in Bratislava. The phenomenon of the punching was calculated according EN1992 and Model Code 2010, and also numerically analyzed by nonlinear methods based on the finite element method. Results of these processes of resistance determination are compared separately for flat slab without and with openings.

There are many analytical methods to solve internal forces of slabs. But structural engineers work with structural analysis software, based mainly of finite element method (FEM). Interpretation of that analysis results may lead to errors during concrete slab reinforcement design. There are some methods to solve the problem. Most familiar are Wood-Armer equations, introduced in 1968. But other methods exists furthermore. It is common, that design engineer doesn’t know, which method his program uses. This article deals with common – not only Wood-Armer - methods of concrete slab reinforcement design incorporating twisting moments, design of skew angle reinforcement etc. Description of selected software approach.

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