Title: Punching Shear in Prestressed Concrete Deck Slabs: A Comprehensive Study

Author(s): Sana Amir, Cor van der Veen, Joost Walraven, and Ane de Boer

Publication: Symposium Paper

Volume: 357

Issue:

Appears on pages(s): 160-186

Keywords: Concrete, Deck slab, Punching shear, Transverse prestressing, Wheel loads, Compressive Membrane Action.

DOI: 10.14359/51738765

Date: 4/1/2023

Abstract:
A large number of bridges in the Netherlands have transversely post tensioned deck slabs cast in-situ between flanges of precast girders and were found to be critical in shear when evaluated by Eurocode 2. To investigate the bearing (punching shear) capacity of such bridges, a 1:2 scale bridge model was constructed in the laboratory and static tests were performed by varying the transverse prestressing level (TPL). A 3D solid, 1:2 scale model of the real bridge, similar to the experimental model, was developed in the finite element software DIANA and several nonlinear analyses were carried out. It was observed that the experimental and numerical ultimate load carrying capacity was much higher than predicted by the governing codes due to lack of consideration of compressive membrane action (CMA). In order to incorporate CMA in the Model Code 2010 (fib 2012) punching shear provisions for prestressed slabs, numerical and theoretical approaches were combined. As a result, sufficient factor of safety was observed when the real bridge design capacity was compared with the design wheel load of Eurocode 1. It was concluded that the existing bridges still had sufficient residual bearing capacity with no problems of serviceability and structural safety.