| The recycled concrete refers to the concrete of which the natural aggregate concrete is some or all replaced by recycled aggregates. Recycled aggregates are made from waste concrete by crushing, processing, grading and screening. Steel-concrete composite beam is a form of structure which is made of upper reinforced concrete plate and the lower beam through the connecting shear. Steel-concrete composite beam not only has reliable capacity, good seismic performance and fatigue resistance, but also can satisfy people’s long-span structures, large space requirements. Steel-recycled concrete composite beam structure combines the advantages of recycled concrete and composite structures which can not only conserve resources, protect the environment, have good social and environmental results but also have good benefits with high capacity, stiffness, shock resistance.This article first studied and analyzed the physical and mechanical properties of recycled concrete which was regarded as green material to compare the difference between recycled aggregates, recycled concrete and natural aggregate, ordinary concrete. Then got on the numerical simulation through ANSYS software to carry out finite element analysis on bending performance of steel-recycled concrete composite beam. When creating composite beam model, the method of transformation parameters was used, three factors which had influence on the bending performance of steel-recycled concrete composite beam were studied, the following conclusions were as follows:1. When compared recycled aggregates with natural aggregate, the performance of both has a certain gap under the influence of several factors such as production processã€matrix concreteã€mortar attached to the surface, but the indicators of recycled aggregates are within the scope of the specification standards.2. By aggregate strengthening method, shortcomings of recycled aggregates can be compensated to a certain extent. After strengthened, overall performance of recycled aggregates are improved so that recycled concrete strength is more in line with the requirements formulated.3. Under different substitution rate of recycled aggregate, the intensity of recycled concrete is lower than that of ordinary concrete. The greater the rate of recycled aggregate, the lower intensity of recycled concrete.4. Compressive failure mode of recycled concrete test cubes, prisms test block is similar to ordinary concrete block, mechanical behavior and failure mechanism are also similar.5. Bending performance of steel-recycled concrete composite beam:(1) Recycled aggregate replacement ratio has little effect on bending performance of steel-recycled concrete composite beam, the load-deflection curve trends of composite beam is similar under different replacement ratio.(2) Flexural performance of composite beam reinforces with the improvement of recycled concrete strength.(3) Beam intensity bring about great impact. Improving strength steel can greatly improve the flexural properties of composite beams. In order to make recycled concrete, steel properties both fully utilized, the appropriate beam intensity should be selected during the composite beam design.Through the study of the physical and mechanical properties of recycled concrete, as well as the analysis on three factors that affect the flexural performance of steel-recycled concrete composite beam structure, it can be drawn that recycled concrete has a certain value in engineering to meet the requirements of green buildings. |
