Camber of Skew Precast Prestressed Concrete Bridge Deck Panels

Abstract

A common problem that most contractors are faced with in slab-bridges’ construction is to predict camber of pre-tensioned or post-tensioned corrugated skew slabs due to prestressing force. It is an important factor to achieve bridge design finished levels without any unforeseen construction cost. Presence of skewedness in bridges makes analysis and design of bridge decks intricate. In this paper, three 3100 mm long post-tensioned corrugated slabs with overall height of 200 mm and 50 mm thickness for both inclined and top parts of specimens, and thickness of 77 mm in the bottom part were studied. Corrugation angle of tested slabs was 60° and skew angle was 20°. Specimens are prestressed by two 15.25 mm diameter strands. Camber measurements were carried out during tests by means of measuring the differences of slab bottom levels. Numerical calculation is done utilizing the Finite Element Analysis Program; ANSYS, taking into consideration initial prestress losses. ANSYS program provides a threedimensional element (Solid 65) with nonlinear model of brittle materials similar to concrete material. Three-dimensional spar element was used for modeling reinforcement and prestressed strands. Comparison between experimental and numerical results is made. Numerical results showed good agreement with experimental results. Keywords: Slab, Concrete, Prestress, Skew, Camber, Post-tensioned, Experimental, Numerical, Non-linear.