International Concrete Abstracts Portal

Title: Precast Concrete Decks for Slab-on-Girder Systems: A New Approach

Author(s): Aftab A. Mufti, Baidar Bakht, and John P. Newhook

Publication: Structural Journal

Volume: 101

Issue: 3

Appears on pages(s): 395-402

Keywords: bridge deck; concrete; corrosion; durability; precast; test

Date: 5/1/2004

Abstract:
Fiber-reinforced concrete (FRC) deck slabs without internal tensile reinforcement are also known as steel-free and corrosion-free deck slabs. The cast-in-place version of these slabs has already been applied to five highway bridges in Canada. This paper describes the significant design details of a 150 mm-thick precast steel-free deck slab supported on girders at a spacing of 3.5 m. The results of tests on full-scale models of the precast slab are also reported. It was found that the precast panels, made composite with the supporting beams, were able to sustain concentrated loads that were several times larger than the factored design loads. The experimental investigation included the study of the panel’s performance to sustain construction loads when it is not connected to the girders. This investigation led to an improved design of the panel, also reported in the paper. When a precast panel without any reinforcement was incorporated in a forestry bridge several years ago, it developed several wide cracks. While these cracks have not impaired the load-carrying capacity of the deck, it is now believed that unsightly wide cracks should be avoided by providing in the panel a crack-control grid of nominal reinforcement, either made of steel or of glass fiber-reinforced polymer (GFRP).