The Shear Strength Analysis Of Simply Supported Reinforced Concrete Deep Beams

The deep beams are those simply supported beams whose ratio between calculation spanand height is less than2and continuous beams whose ratio is less than2.5.Based on differentcalculation theory and calculation model,the bending strength and shearing strength in deepbeam will have significant difference conclusion.The engineer often encounter troubles due tothe application of deep beams in engineering practice.This thesis makes an inquiry into thecalculating method of shear strength of simply supported reinforced concrete deep beams,based on plastic theory of concrete and upper bound method. Four failure mechanisms areestablished while shearing failure and the limit load is determined.In this thesis, firstly, basic principle or plastic theory of concrete is briefly describedincluding the plastic properties of concrete and steel, yield line, deformation and strain as wellas energy balance. The method of using upper bound method to answer limit loads isdetermined. Then, according to the mentioned principles, four failure mechanisms of the shearstrength of simply supported reinforced concrete deep beams are established. By calculatingand analyzing, using the principle of external work equal to internal energy, the limit loadsstating failure mechanisms are answered. Meanwhile, some relation parameters are deducedfor the analyzed. Then, by four reinforced concrete deep beams that laying the different shearreinforcement (including reinforcement without web, reinforcement with only horizontal web,reinforcement with only vertical web and reinforcements with both horizontal and verticalweb), and test results of such131test beams are used to test and verify the rationality of thefour failure mechanisms established,and to statistically analyze these calculated results. Theresult shows that the calculated solutions from these failure mechanisms are matched wellwith the tested results, which shows that the established failure mechanisms are rational.Finally, a calculated factor reasonably reflecting the relation between calculated limit loadsand tested failure loads is determined.