Serviceability Limit States According to the New Eurocode 2 Proposal: Description and Justification of the Proposed Changes

Abstract

In this paper the main changes introduced into FprEN 1992-1-1:20231 [1] with respect to the current version of EC2 (EN 1992-1-1:2004) [2] with regard to cracking and deflection calculations are introduced and justified. The changes introduced into the cracking formulation account for the variation of stresses in the tensioned zones for bending, the effect of the casting position and the influence of curvature on the increase of surface crack widths. The introduction of these effects, together with a reformulation of the effective area allow for a reduction of scatter in the model when compared to experimental data. For deflections, a simplified method is introduced which is fully consistent with the general method and allows practical application by providing correction factors to be applied to linear elastic calculations. From this method a formulation for the slenderness limits is deduced. This formulation is the basis for the table-based method to avoid deflection calculations. Finally, coefficients are derived to translate the slenderness limits of beams to the slenderness limits of slabs supported on isolated columns and slabs supported on walls.