Home > News > news >

Advanced civil infrastructure materials

News Group

    Advanced civil infrastructure materials

    Issue Time:2013-10-12

    Sotiropoulos (1991) assembled and tested two FRP bridge superstructure systems consisting of bridge decks and stringers, they used a simplified finite-element model with equivalent plates representing the stringers and the cellular deck, and results were correlated with experimental data. Burnside et al. (1993) presented a design optimization of an all-composite bridge deck; cellular-box

    and stiffened-box geometries were optimized with consideration of deflection and buckling. In 1997, the first all-composite bridge deck in the U.S., consisting of a honeycomb sandwich, was built in Russel (Plunkett 1997). Later, two highway bridgeswereconstructedwith a modular  FRP composite deck in West Virginia (Lopez-Anido et al. 1998a); one was built as an all-composite shortspandeck/stringer system and the other as a modular FRP deck supported by steel stingers. Fatigue and failure characteristics of a modular deck were investigated by Lopez-Anido et al. (1998a;b) and satisfactory performance was observed. An overview on research and applications of fiber-reinforced polymeric bridge decks was presented by Zureick (1997) and Bakis et al. (2002). A critical obstacle to the widespread use and application of FRP structures in construction is the lack of simplified and practical design guidelines. Unlike standard materials (e.g., steel and concrete), FRP composites are typically orthotropic or anisotropic, and their analyses are much more complex. For example, while changes in the geometry of  FRP shapes can be easily related

    to changes in stiffness, changes in the material constituents do not lead to such obvious results. In addition, shear deformations in pultruded FRP composite materials are usually significant, and therefore, the modeling of FRP structural

    components should account for shear effects. For applications to pedestrian and vehicular FRP bridges, there is a need to develop simplified design equations and procedures, which should provide relatively accurate predictions of bridge behavior and be easily implemented by practicing engineers. Closed-form, mechanics-based methods for designing sectional stiffness properties of composite shapes were detailed by Barbero et al. (1993) and Davalos and Qiao (1999). These mechanics concepts combined with

    elastic equivalent analysis can be translated into approximate methods for estimating the equivalent orthotropic plate behavior of decks. In this way, deck designs can be defined as assembles of structurally efficient and easy-to-manufacture pultruded composite sections. A systematic analysis and design approach for single-span FRP deck-and-stringer bridges was presented by Qiao et al. (2000); while systematic methods for optimizing pultruded shapes have been developed (Davalos et al. 1996a; Qiao et al. 1998), optimized deck designs are largely derived by trial and error. A systemic design approach and procedure for FRP composite structures

    is presented in this chapter. First, the material properties involving constituent materials, ply properties,andlaminatedpanelengineering properties are Advanced fibre-reinforced polymer