An Experimental Study On The Shearing Strength Of Recycled Coarse Aggregate Concrete And The Shearing Property Of Beams

For the purpose of the application of recycled concrete in production and design, this paper, based on the researches carried out at home and abroad on mechanical property of recycled concrete, studies the shearing strength of recycled concrete and the shearing property of beams, which were produced by using different replacement rates of0%,50%and100%respectively.On the basis of equal strength mix proportion designs, this test used nine recycled concrete beams, which had equal altitude and varying width with four points under stress, to test the shearing property of recycled concrete under different replacement rates of0%,50%and100%respectively. It analyzed the shearing strength, shear failure mechanism and shear deformation performance of recycled concrete. Meanwhile, it studied the regular pattern of shear stress-strain relationship and the varying pattern of shear modulus according to the datum. In the end, the shear stress-strain equations and the formulae of shear modulus have been put forward in this paper. The study indicates that recycled concrete is similar to ordinary concrete on shear failure shape, but brittleness becomes more obvious with the increase of the replacement rates. Under the conditions of the test, the recycled concrete with the replacement rate of50%shows lower shear strength than ordinary concrete, while the shear strength is slightly higher than that of ordinary concrete when the replacement rate is100%, but it shows larger discrete. The peak shear strain of recycled concrete increases with the increase of shear strength and its shear modulus lowers than ordinary concrete.On the basic of the achievement before,by testing the shear capacity of12recycled concrete beams under the, the author observed the shear failure mode of recycled concrete and studied the shear loading features of the beams and their corresponding failure mechanism. Combined with the experimental data, this paper also analyzes the influence of recycled concrete’s replacement rates, shear span ratio and stirrup reinforcement ratio on the shear property of the recycled concrete beams. In accordance with shear force balance mechanism, the author used regression analysis to analyze bearing capacity datum and put forward the shear capacity equation of recycled concrete under the circumstance of equal strength, which provides the basis for its application in architectural design. The test indicates that the shear failure mode of recycled concrete is similar to that of the ordinary concrete, but its frangibility is more obvious. Under the test condition, the shear capacity of recycled concrete beams is lower than that of the ordinary concrete beams when the replacement rate is50%, whereas the shear capacity of recycled concrete beams is slightly higher when the replacement rate is100%. Shear capacity decreases as shear span ratio increases, but it increases as stirrup reinforcement ratio rises. Meanwhile, basing on the study of parameters, the author suggests a formula for the shear capacity of recycled concrete beams of different replacement rates.This test method is effective to study the shear strength of recycled concrete and the shear properties of recycled concrete beams and it provides a basis for the application of recycled concrete.