Numerical analysis of the effect of variation of eccentricity of unbonded post-tensioned tendons on the structural behavior of flat slabs

DOI: https://doi.org/10.21041/ra.v12i2.570
Keywords: post-tensioned concrete, unbonded tendons, strand eccentricity

Abstract

In this study, the effect of variations of eccentricity of tendons in unbonded post-tensioned flat slabs was evaluated. The correct positioning of strands in the assembly of unbonded post-tensioned flat slabs is essential for the structural system to achieve adequate performance and safety. Four different slab models were analyzed with variations in the height of the strands at different positions providing the change in eccentricity and increases in the number of tendons. Pre-compression stresses, stresses on the bottom and top faces, center vertical displacements, load balancing and passive reinforcement of the slabs were evaluated. The ADAPT Floor Pro commercial software was used for the analyses with the design conforming with standard NBR 6118:2014 and recommendations from standard ACI 318:2019. For the models evaluated, it was found that the variation in the eccentricity of the strands in the bottom face of the slab reduced the applied stresses more than variations in the top face.

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Published
2022-05-01
How to Cite
Cattelan Antocheves de Lima, R., Cielo, L., Lübeck, A., & Santos Neto, A. B. da S. (2022). Numerical analysis of the effect of variation of eccentricity of unbonded post-tensioned tendons on the structural behavior of flat slabs. Revista ALCONPAT, 12(2), 210 - 226. https://doi.org/10.21041/ra.v12i2.570
Issue
Vol. 12 No. 2 (2022): Volume 12, Issue 2 (2022)
Section
Basic Research

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