Experimental Study On Fatigue Performance Of Rubber Concrete Under Uniaxial Compression

In recent years,the rapid development of China’s economy,the rapid increase of traffic also caused a sharp increase in the use of automobile tires,and resulting in more and more waste tires.Rubber tires are composed of polymer organic materials,which are difficult to decompose naturally under ordinary environmental conditions.If they are not properly disposed,they will not only cause waste of resources,but also pollute the environment.Crumb Rubber Concrete(CRC)can not only turn waste into treasure but also improve the fatigue life of Concrete by grinding waste Rubber tires into particles and mixing them into ordinary cement Concrete.Rubber concrete has good crack resistance and deformation ability,fine features,such as high energy consumption and great toughness for further mining engineering application value of rubber concrete,the rubber concrete,this paper studies the uniaxial compression fatigue property of,for its application in railway,highway bridge pier column,large equipment base,gravity fields of oil drilling platform,The research work of this paper is as follows:Taking C30 ordinary cement concrete as the benchmark,rubber particles of 10 mesh,30 mesh and 50 mesh were mixed into ordinary concrete to make rubber concrete according to the replacement amount of 5(4),(16)(15)(4)and 1 5(4)of the same volume of medium sand respectively.Through the mechanical properties tests of the compressive strength,splitting tensile strength and bending strength of the specimens,the rubber particle size was optimized.The optimized rubber particle size was used to prepare rubber concrete test blocks with 5(4),(16)(15)(4)and 1 5(4)of the same volume of sand,and the uniaxial compression fatigue test under constant amplitude cyclic loading was carried out.The test results show that the fatigue life of rubber concrete is better than that of ordinary cement concrete under the same stress level,and the fatigue life of concrete increases with the increase of rubber content.Under different loading conditions,the fatigue life of rubber concrete increases with the decrease of stress level.Under cyclic fatigue load,rubber concrete experiences three stages: rapid strain growth stage,stable strain development stage,rapid strain development and even failure stage.The proportion of these three stages is about 10(4)～15(4),70(4)～80(4)and 10(4)～15(4)of fatigue life,respectively.The distribution law of fatigue life of rubber concrete under constant amplitude cyclic load is obtained by analyzing the test results of rubber concrete fatigue life with probability statistics method.The results show that the fatigue life model of rubber concrete obeys both lognormal distribution and two-parameter W eibull distribution.The fitting results of P-N graph and Kolmogorov test show that the two-parameter W eibull distribution is better than the lognormal distribution.The fatigue life reliability of rubber concrete with two-parameter W eibull distribution model is analyzed by linear regression using double logarithm equation.The S-N curve and P-S-N curve are obtained respectively,and then the fatigue ultimate strength is calculated.Compared with ordinary concrete,the ultimate fatigue strength of concrete with three kinds of rubber content is not significantly improved,but its fatigue performance will be significantly improved.