ABSTRACT
The flexural capacity of unrestrained concrete slabs is governed by the percentage and strength of the reinforcement and only marginally by the concrete strength (Zheng et al 2010). In contrast, in-plane restrained slabs fail in compression due to an internal arching action and so the capacity is significantly influenced by the concrete compressive strength in addition to the stiffness of the inplane restraint (Taylor et al 2001). It was shown in recent study that the utilization of the benefits of arching action and FRP reinforcement should produce an economic and durable concrete deck slabs
1 INTRODUCTION
Deterioration of our ageing concrete infrastructure and a drive for lower carbon, yet durable, concrete is a major challenge facing designers, inspectors, assessors and owners. The principle of sustainable construction stands on a basis of material together with structural design optimization, which can result in low-cycle costs. Self-Compacting Concrete (SCC) with additional mineral (GarciaTaengua et al. 2015) and Fiber Reinforced Polymer (FRP) (Taylor and Mullin 2006) are two engineering materials which gained wide attention from researchers and engineers due to their advantage. By using the post-wastes materials, such as Ground Granulated Blast Furnace Slag (GGBS) and Limestone Powder (LSP), SCC is high-performance and low-energy concrete with high workability and consistency allowing it to flow under its own weight without vibration and making the construction of heavily congested structural elements easier (Garcia-Taengua et al. 2015; Sonebi and Nanukuttan 2009). As well known, FRP reinforcement with excellent mechanical properties and non-characteristics is being used as a replacement of conventional steel reinforcement (El-Salakawy
(Gobithas et al. 2013; Zheng et al. 2012). The previous laboratory tests showed the beneficial influence of arching action on service behavior despite the lower elastic modulus of FRP rebar compared to steel (Taylor and Mullin 2006; Zheng et al 2012; Gobithas et al. 2013). However, the study of structural behaivour SCC bridge deck with FRP bars in a real bridge has not been developed. To extend the understanding of arching action in SCC slabs with FRP bars, this paper reveals a field test and study on SCC slabs reinforced with corrosion resistant Basalt Fibre Reinforced Polymer (BFRP) rebars to use in a real bridge. Hence, this study on a real bridge is aimed at providing information on the service behavior in a real bridge deck and aimed at corroborating the findings of laboratory tests. Although a primary objective is to test BFRP reinforced SCC deck slabs with external restraint typical of many bridge in Europe, the field test is also designed to investigate the influence of reinforcing materials (BFRP vs. Steel) and reinforcement percentage of the serviceability of a typical bridge deck slab in practice. As shown in Figure 1, a total six panels were tested under a concentrated load (see Figure 2) of round three times the maximum wheel load given by Europe Code (BS EN 2004), that is 150 kN. The deflections along the centre line of deck soffit and strain values of BFRP reinforcing bars were also measured. Comparisons between BFRP reinforced SCC deck slab and equivalent steel reinforced SCC deck slabs were carried out using discrete optical sensors embedded in the concrete.
