| Steel plate-concrete composite bridge deck is a new-type of composite bridge deck consisting of steel plate and concrete, which is joined by the shear connectors such as stud, PBL shear connectors and other types of shear connectors. Steel plate-concrete bridge deck can effectively achieve the design of wide span bridge deck due to its bigger flexural stiffness and bearing capacity comparing with traditional bridge decks. In the construction of bridge deck, it can function as a formwork, and the use of steel plate forms saves a significant amount of time. At the same time, the plate steel-concrete bridge deck has more advantage to speed up the construction progress and reduce traffic impact during revision and reconstruction of the reinforced concrete bridge deck. Therefore, the steel plate-concrete composite bridge deck has a wide application prospect. In order to study the static and fatigue behaviour of a new type of steel plate-concrete composite bridges decks, static loading experiment of four specimens of the composite decks was carried out and constant-amplitude fatigue tests of ten specimens were conducted.The results of static tests of 4 composite bridge decks show that all the composite bridge decks have high bending stiffness, good ductility as well as better bearing capacity, and share the same failure mode, typical bending failure. For further study on the static behavior of composite bridges decks, the specimens are analyzed by the finite element analysis software ABAQUS under the static loading.In fatigue tests, the study focused on the influence of three main factors including stud layout, the number of PBL connecters and fatigue load level on the failure modes and fatigue damage degree of composite bridge decks under fatigue load. During the experiments, some key factors, such as the dynamic deflection, strains of concrete and steel plate, residual deflection and residual bearing capacity were measured and analyzed. From the test results, it can be concluded that the failure life of composite bridge decks directly relate to the margin of the fatigue stress of plain steel, and the number of PBL connecters and stud layout have little influence on it. Composite deck specimens'fatigue failures are all failed due to the steel plate collapsing at certain fatigue load circle and compressive zone of concrete crushing.Finally, the calculation method of fatigue life and stiffness degradation of composite bridge decks is proposed based on the fatigue experiment. |
