Analysis On The Demarcation Between One-Way And Two-Way Deck Of Steel-Concrete Composite Bridge

With the application and extension of steel-concrete composite deck in bridge engineering, it was meaningful to study the mechanical performance of steel-concrete composite slab. Generally, one-way or two-way slab was often used to simplify the complex 3-D structure to 2-D model. This is valuable to engineer. Though the codes at home and abroad had made a definition on the demarcation between one-way and two-way slab based on the stress mechanism of concrete slab, there is no corresponding definition for steel-concrete composite slab. Compared with the traditional concrete slab, steel-concrete composite slab has a quite large difference in higher proportion of steel plate. Direct applying the demarcation of concrete slab to steel-concrete composite slab is unfounded and can’t make the best of its good economy.In order to study the demarcation between the one-way and two-way of steel-concrete composite slab, a special research was carried out. Firstly, the geometry parameters of steel-concrete composite slab were designed based on several real steel-concrete composite structure projects. Secondly, finite element modals were built for steel-concrete composite slab under different boundary conditions, shear connection degree and uniform load. Thirdly, elastic and elasto-plastic models were introduced to investigate the deformation, reaction and force influenced by material and boundary. Furthermore, the coefficient of load transfer was introduced to study the load distribution of steel-concrete composite slab. Finally, the side length ratio equals to 3 and 3.5 was suggested to determine the demarcation under elastic and elasto-plastic condition, respectively.