Study The Effective Width Of Steel Truss-concrete Composite Beam

Composite structure is the structure that the same cross-section made up by two or more materials. As the needs of engineering, steel-concrete composite structure is used more and more in recent years. Steel truss-concrete composite beam is one kind of steel-concrete composite structure. It is composited by steel truss and concrete slab which are connected by connecting pieces and bear loads together. This structure has played a very good tensile property of steel and the compressive properties of concrete, at the same time it has big stiffness, big load support capability, small flexure and small construction cost. At present steel-concrete composite beam has been widely used in the bridge structure, large space structure.The effective width of the concrete slab is a very important factor in designing steel-concrete composite beam. It impacts the carrying capacity of composite beams directly. Concrete slab will be vertical shear as shear transfer between concrete slab and steel truss when the composite beams under load. With the reason of the vertical shear, non-uniform stress distribution can be appeared in concrete board and stress mutations phenomenon will be occurred at the connection of the concrete slab and the web. The phenomenon described above is called the shear lag or Shear lag effect. The elementary beam theory of the mechanics materials which presumes concrete slab section stress equal everywhere can not be used. In recent years, there are a mass of research on effective width of steel-concrete composite beam in China. But the provision of the effective width is not fully and strict as various forms of truss beams. I research the effective width of Steel truss-concrete composite beam with Finite Element Simulation hardly in order to resolve more problem of effective width of Steel concrete composite beam.This paper researches dozens of steel truss-concrete composite beam and 3 Steel truss-concrete composite beams and analyzes several dominant factors about steel truss-concrete composite beam, such as the arrangement mode of male pin (Shear connection degree), form of the loads, steel's yielding strength, concrete strength, thickness of the concrete slab, width-span ratio of the composite beam, span-depth ratio of the composite beam. Using the Finite Element Method to calculate the effective width of concrete slab at different load stages. Then Summarize and contrast the effective width of the Single-Pin steel truss-concrete composite beam and 3 Steel Truss-concrete composite beams based on the different factors and I put forward some advice to value the effective width of the Steel truss-concrete composite beam's concrete flange plate.