Influence of the Shear Cap Size and Stiffness on the Distribution of Shear Forces in Flat Slabs

Abstract

The scope of this paper is to investigate analytically and numerically the influence of shear cap size and stiffness on the distribution of shear forces in flat slabs in a slab–column-connections-reinforced concrete structure. The effect of support (shear cap) stiffness on the calculation of the length of the shear control perimeter according to the available methods is presented. Based on the analysis, the authors indicate in what range of support stiffness the corner concentrations become important in the calculation of the punching resistance. For shear caps with high flexibility (α1 ≤ 0.5), the concentration of internal forces in the corners does not occur. The authors compare the numerical results obtained from the calculation methods and indicate the correlations, which can be useful guidance for structural designers. In the case of large shear caps, the simplified MC2010 method gives a significantly lower value of the effective control perimeter length compared to more accurate methods. This paper is intended to provide scientists, civil engineers, and designers with guidelines on which factors influence punching shear load capacity of the slab–column connections with shear caps.

Construction and Building Materials: Masonry Structures and Reinforced Concrete Structures

“…Theoretical tests on slab and column systems are described by Grabski and Ambroziak in the paper [8]. The effect of size and stiffness of thickening and widening of the slab on the distribution of shear forces in flat slabs in a slab-column connection reinforced concrete structure was analysed.…”

“…Also, the advanced FEM models could be used in future analyses. The original methods of validation were used to develop reliable and advanced models of reinforced concrete [1], slab and column systems [8], columns [22], and strengthening [19]. The FEM analyses were also used to model the thermomechanical process in ageing mass reinforced concrete constructions [6,18].…”

Archives of Civil Engineering

“…Stress concentrations at corners contribute to a reduction in punching shear resistance. The issue of punching outward of the head, the stiffness of the head is an important parameter affecting the force concentrations at the corners of the support and the resistance of the connection [46,47]. The proposal for a method to verify the punching resistance of very large supports based on the EN 1992-1-1 (EC2) [48] standard is given.…”