Nonlinear finite element modeling of post-tensioned two-way concrete slabs

Post-tensioning is a technique that was used for constructions of (buildings, bridges, towers and offshore structures… etc..), Due to its efficiency and economy for achieving the requirements of long span with small depth. Post-tensioned concrete two-way slabs are one of the widely used slabs because of their good performance and cost effective compared with another slab type. This thesis investigates the structural behavior of post-tensioned two-way spanning concrete slabs. A nonlinear finite element model for the analysis of post- tensioned bonded concrete slabs 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 behavior, crack pattern in concrete and the failure modes are presented. The numerical analysis was conducted by the finite element ANSYS software and was validated by post-tensioned two-way concrete slab chosen from literature. A parametric study was conducted to investigate the effect of several selected parameters on the overall behavior of post-tensioned two-way concrete slab. The parameters are the effect of tendon layout, type of support, type of loading, position of the tendons, number and area of the tendons. Comparison between one-direction and two-direction tendon layout with the same number of tendons showed that two-direction tendon slab has higher failure load capacity.