Development And Study On An Innovative FRP Bridge Deck

FRP (Fiber reinforced polymer) is a new structural material in civil engineering in recent years. FRP hollow decks are the typical FRP structure elements, which can act as bridge superstructures, building floor slabs and walls. FRP bridge deck is one of the most promising applications among them. In this research, a new configuration is devised and an innovative FRP bridge deck with this configuration is developed and fabricated. The mechanism of the configuration is analyzed and explained. Furthermore, the design theory of the flexural members is studied. The design procedure for FRP deck is proposed, and the approaches for every step are also suggested.The behavior of FRP deck mainly depends on the connections between the components and the section configuration due to FRP material properties such as orthotropic and heterogeneous. Two types of FRP decks are tested firstly. Their deformation behaviors and failure characteristics are investigated. The failure characteristics of various FRP decks in literatures are also summarized. Based on the researches, the outside filament-wound reinforcement (OFR), a new configuration is put forward, which is expected to strengthen the connections between the components. It is shown in the comparison experiments that the OFR increases the deformation capacity and the strength of the FRP decks and also slow down the failure progress. The existing FRP decks in literatures are investigated, and the different section configurations are analyzed and compared with finite element program. Based on these, an innovative FRP deck with OFR, named HD deck, is developed. HD deck is composed of two pultruded surface plates, four filament-wound core tubes and OFR. The products are fabricated after optimization design. Then, three HD decks with different thicknesses or winding angles of OFR are tested under static load, and one under fatigue load. The tests show that the developed HD decks are satisfied the deformation limitation under the Truck-Load over 20 Degree and their strengths are more than 4 times higher than that of the design load; and further the stiffness of a HD deck after 2 millions of fatigue loading decreases no more than 10% of the original. Furthermore, the acting mechanism of OFR is analyzed with finite element program. It is shown that OFR can provide the restriction to the fracture in the interface of the bonded components and can stiffen the attached plates in local.Due to the differences between FRP and the conventional structural materials, the performance indices and the safety storage of the flexural members are studied. It is indicated that the safety margin are composed of the loading capacity and the deformability safety margin. Four performance indices are presented to describe the loading capacity and the deformability safety margin of various flexural members generally. Moreover by their use, the same safety margin for FRP members and the conventional materials members is obtained. Finally, the design procedure of FRP deck is proposed, and the approach for each step is suggested.