[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.12989/sem.2017.62.5.595

Modelling of bonded and unbonded post-tensioned concrete flat slabs under flexural and thermal loading

Mohammed, Abbas H. (Department of Civil Engineering, Gaziantep University)
Taysi, Nildem (Department of Civil Engineering, Gaziantep University)

Publication Information

Structural Engineering and Mechanics / v.62, no.5, 2017 , pp. 595-606 More about this Journal

Abstract

During their life span, post-tensioned concrete structures may be exposed to thermal loads. Therefore, there has been a growing interest in research on the advanced analysis and design of post-tensioned concrete slabs subjected to thermal loads. This paper investigates the structural behaviour of post-tensioned one-way spanning concrete slabs. A nonlinear finite element model for the analysis of post- tensioned unbonded and bonded concrete slabs at elevated temperatures was developed. The interface between the tendon and surrounding concrete was also modelled, allowing the tendon to retain its profile shape during the deformation of the slab. The load-deflection behaviour, load-force behaviour in the tendon, and the failure modes are presented. The numerical analysis was conducted by the finite element ANSYS software and was carried out on two different one-way concrete slabs chosen from literature. A parametric study was conducted to investigate the effect of several selected parameters on the overall behavior of post-tensioned one-way concrete slab. These parameters include the effect of tendon bonding, the effect of thermal loading and the effect of tendon profile. Comparison between uniform thermal loading and nonuniform thermal loading showed that restrained post tensioned slab with bottom surface hotter has smaller failure load capacity.

Keywords

post-tensioned slabs; computer modelling; finite element method; concrete; unbonded tendons; bonded tendons; thermal loading;

Citations & Related Records

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