Study On The Shear Performances Of Heterogeneous-overlapped-composite Rc

With the development of the utilization of the practical engineering, much moreflexural members with wide span and high strength are used more and more widely.Combine the bearing capacity of RC, concrete can be in two-way stress states duringloaded. So If use traditional RC by a single material, it will be bound to leadperformance waste of parts, the functions cannot reach their full potential, that maybe not ideal in economy and project application. For all this, the research scholars inHIT not only put forward a special RC, which is formed by high strength concrete incompressive region and common concrete in tensile area, but also preliminary studiedthe flexural behavior of this special RC.Based on the principle of economical, and follow the philosophy of “green buildingand environmental architecture”.This paper at the foundation of previous studies,carried out studies on shear capacity of heterogeneous, overlapped and composite(HOC) RC by introducing RAC, as well as analyzed the shear properties, shearmechanism and performance on overlapped interface by using numerical simulationsoftware,called ANSYS. Pilot studied the practical methods for calculation for theshear capacity of HOC-RC by drawing lessons from the shear behavior of thetruss-arch model of ordinary reinforced concrete beam. Specific tasks are as follows:Firstly, in consideration that the reinforcement ratio, variety of overlappedmaterials and the steel fiber may mainly affect the shearing properties of HOC-RC,this research designed7test samples of RC, including one contrast beam with RACand six test beams with HOC, and analyzed by static test. The results indicate that：(1) the shear capacity of HOC-RC increases with the increase of reinforcementratios in a proper range;(2) the shear capacity of HOC-RC generally happier than that of reinforcedconcrete beam by a single material;(3) HOC-RC takes account of the two-way stress In the cross section, reasonablyincreases the utilization ratio of any material, and its ductility is much more higherthan that of reinforced concrete beam by a single material; (4) In the making process, HOC-RC is first leveled and then fluffed,called coinprocess, which can increase the contact area of two types of concrete to improve thecomponent strengths;(5) steel fiber has a certain contribution for the compressive strength of concrete,while a more important role may be reflected in the crack resistance and the ductilityof components. The incorporation ofsteel fiber can reinforce strength and deflection of specimen clearly.Secondly, this paper analyzed the shearing properties of HOC-RC through thenumerical simulation software, called ANSYS. Separately defined the constitutiverelations of two types of concrete, and linked up the two-level concrete byshared-nodes. Simulation results show that: two-level concrete bonded safety, theoverall coordination was well, had no boundary slippage, the result of the simulationand the experiment agreed well, the influence rules were in keeping with theexperimental results.And thirdly, combined all the factors of the shear capacity of HOC-RC, this studytook the stirrup yield and the pressure area concrete crush as two keys. Analyzed thestress at the location on the cross section by using truss-arch model, and advised anequation to calculate ultimate shear-resistant capacity of HOC-RC.