Experimental Study On Mechanics And Crack Resistance Of Rubber Granular Concrete

In the "China's 21 st Century Agenda" program,the recycling of waste rubber has been clearly included,and it is planned to be In terms of continuous economic development.Compared with ordinary concrete,rubber granular concrete has better ductility,impermeability and crack resistance.Based on this,the research on the properties of rubber granular concrete has great environmental and scientific significance.Through experiments,the result of different volume substitution rate and diameter of rubber on the mechanical properties of reference concrete with different ages was studied systematically.The ratios of rubber particles equal volume replacement of fine aggregates are 0%,5%,10%,15% and 20%,the particle size is powdered(0.18mm?0.25mm)and granular(0.55mm?0.85 mm and 2mm?4mm)three kinds of rubber;in order to improve the performance of rubber granular concrete,separate in rubber granular concrete Adding an equal volume of 0.05%,0.1%,0.15%,and 0.2% of the cement mass as a strength compensation method to study the effect of different content retarders on the setting time and mechanical properties of concrete;to study rubber particles The anti-cracking performance of concrete,the outer square inner circle eccentric restraint method was used to study the influence of the external retarder on the anti-cracking performance of rubber granular concrete.Compare the cracking of ordinary concrete,rubber granular concrete,concrete with retarder and concrete mixed with rubber granules and retarder at the same time;and study the mechanical properties of the four ratios.The test results are as follows: as the particle size of the rubber particles increases and the amount of rubber particles increases,the slump of the benchmark concrete decreases;the smaller the size of the rubber particles added to the concrete and the more the amount of rubber particles,The more obvious the impact of cement strength;When the particle size is the same,the flexural strength decreases as the rubber particles are added;when the amount is the same,the larger the particle size,the lower the flexural strength.The rubber granular concrete modification test showed that the mechanical properties of the test block after adding retarder showed a trend of enlargement anddiminution with the retarder content.When the content is 0.1%,The compressive and flexural strengths of rubber retarded concrete are increased by 6% and 5% respectively,and the extension of the initial setting time of concrete is the most obvious,that is,from the mechanical point of view,the optimal content of this retarder is 0.1%;Addition reduces the compression ratio of concrete,and the strength of concrete reduced by the addition of rubber particles is supplemented;in the anti-cracking test of rubber retarded concrete,it is found that the addition of rubber particles and retarder to concrete can significantly effectively improve The anti-cracking performance of concrete is best when a certain amount of rubber particles and retarder are added at the same time,which is better than that of concrete with rubber particles,retarder concrete and benchmark concrete.