The article deals with non-linear modeling of slab-column connection which represents a fragment of flat slab supported by a column and loaded up to the punching shear failure. The aim of this parametrical study is the analysis of the length of reduced control perimeters in the case of columns with significantly elongated rectangular cross-section. The non-linear analysis was performed in program Atena and calibrated by test results obtained from the laboratory experiments carried out at Slovak University of Technology in Bratislava. The results of non-linear analysis are compared with the values of shear resistance calculated according to the current Eurocode 2 model; fib Model Code 2010 and model proposed for the second generation of Eurocode 2 based on the Critical shear crack theory. The reliability of the models is evaluated by comparison of the results of numerical analyses and previously mentioned design models.

The paper deals with the loading test results of an experimental reinforced concrete flat slab fragment, which was supported by an elongated rectangular column. The slab specimens were 200 mm thick and were designed without any shear reinforcement. By experimentally obtained punching shear resistance, the accuracy of the standard design models for prediction punching resistance was compared. The results of the experiments were also compared with the results of a numerical non-linear analysis performed in the Atena program.

This paper deals with both linear and non-linear analysis of shear forces distribution in the area near the supports of the flat slabs. With a cross-section ratio of cmax / cmin > 3, the main amount of the shear stress is concentrated near the column or wall corners bases. As a consequence of this phenomenon, it is necessary to reduce the control perimeter when evaluating the punching shear resistance of a flat slab. The fragments of the flat slabs with the thickness of 200 mm supported by a wall with various loading conditions were analyzed. The results according to the Eurocode 2 were compared to a non-linear shear resistance evaluation that was calibrated based on the results from the previous experiments. Based on thus evaluated punching shear resistances, the theoretical reduced control perimeter was determined and subsequently it was compared to design model Eurocode 2. The physical basis for determining reduced control perimeters is based on the shear force concentration near the support.

The paper deals with the loading test results of an experimental reinforced concrete flat slab fragment, which was supported by an elongated rectangular column. The slab specimen was 200 mm thick and was without shear reinforcement. By experimentally obtained punching capacity, the accuracy of the standard design models for prediction punching resistance will be compared. The results of the experiment were also compared with the results of a numerical nonlinear analysis performed in the Atena program.

This article deals with the punching capacity of a flat slab fragment supported by an internal atypically elongated column. Based on the results of this analysis and the application of Critical Shear Crack Theory, the reliability of two design models was determined. The CSCT model is a mechanical model where the shear force transferred by concrete in shear crack can be determined by accounting for the roughness and opening of a critical shear crack. The crack width is proportional to the slab rotation, which was obtained from a nonlinear program Atena and from experimental test and shear capacity was obtained by integrating the shear strength along the control perimeter. The aim of this analysis was to compare the application of CSCT in non-linear analysis and experimental test to point out the significant difference between obtained results, which shows the importance of experimental tests realization. Non-linear analyses provided unsafe results. Contrary the currently used EC2 model provided safe results when reduction of the control perimeter was applied. The best results were obtained in a combination of the CSCT model with measured rotations of the slab specimen.