Experiment Study And Finite Element Analysis On Shear Capacity Of Reinforced Concrete Deep Beam With 600MPa Reinforcement

In today's construction industry,deep beams still play an important role,especially in tall buildings,its outstanding bearing capacity has been favored.Because the stress mechanism of deep beam is different from that of shallow beam,the shear failure of deep beam generally occurs.Up to now,it has been found that there are many factors affecting the shear performance of deep beam,which still can not reach a unified statement.In the calculation formula of code for design of concrete structures(gb50010-2010),the factors affecting the shear capacity of deep beams are: material strength,shear span ratio,geometric dimension of test piece,reinforcement content and layout.In aci318m-14,the bearing capacity of deep beams is mainly calculated based on the strut and tie model,i.e.the main factors affecting the bearing capacity of deep beams are: concrete strength,longitudinal reinforcement strength and reinforcement ratio,section area of compression bar,shear span ratio,etc.In order to study the influence of various factors on the ultimate bearing capacity of deep beams,this paper studies the shear bearing capacity test of deep beams with 600 MPa reinforced concrete,which not only further explores the stress characteristics and ultimate states of deep beams,but also provides a reference test basis for the application of high-strength reinforcement in deep beams.The main work is as follows:(1)for 8 concrete deep beams with 600 MPa longitudinal bars of the same size,the effects on cracking load,limit load,steel bar strain,span deflection change,concrete strain,crack development were studied with different shear span ratio(0.3-0.9),longitudinal reinforcement ratio(0.27%-1.27%)and stirrups reinforcement ratio(0-0.5%).The results show that the longitudinal reinforcement ratio and stirrup reinforcement ratio have certain influence on the shear performance of deep beams,and the shear span ratio has more significant influence on the shear performance of deep beams.(2)The theoretical calculation of the bearing capacity of the test deep beam is carried out by using the codes of China,the United States,Europe and Canada,and the theoretical calculation is compared with the test results.The results show that the chinese code and american code theory are closer to the test value,and the calculation results are less discrete,while the european code and canadian code have higher safety reserve.(3)ANSYS is used to simulate the test deep beam,and the results are compared with the test results.It is found that the simulation results of midspan deflection,reinforcement strain,concrete stress and ultimate bearing capacity of the deep beam are in good agreement with the test results,and there is a large difference between the cracking load and the test results.As a whole,the simulation results are ideal,and the error is within the acceptable range.