等强条件下橡胶微粒混凝土抗压特性及弹性模量研究

掺加橡胶微粒可以明显改善混凝土的力学特性。采用橡胶微粒等体积取代细骨料的方法,通过不断调整配合比,反复试验配制出橡胶微粒体积掺量分别为0%、10%和15%的等强度(30 MPa)橡胶微粒混凝土,探讨橡胶微粒混凝土的抗压强度变化规律,以及在等强条件下不同橡胶微粒掺量对混凝土弹性模量的影响。结果表明:掺入橡胶后,混凝土的前期强度(3 d和7 d)发展较基准混凝土变缓,7 d以及14 d后强度出现较大幅度的增长,28 d后各个配比混凝土立方体抗压强度增幅不大;掺入一定量的橡胶后,混凝土的抗裂性能得到了一定程度的改善,橡胶微粒体积掺量越大,试件受压破坏后的完整性越好;掺入橡胶后,混凝土的弹性模量呈现出近乎线性的大幅下降趋势。

Compressive Property and Elasticity Modulus of Crumb Rubber Concrete at Equal Strength

The mechanical properties of concrete can be improved by adding rubber particles.Through the method of replacing the fine aggregate with equal volume of rubber particles and adjusting the mixture ratio repeatedly,we got the rubber particle concrete with volume fraction of rubber particles of 0,10％ and 15％ at equal strength (30 MPa),then the compressive strength of rubber particles,and the influence of different rubber particles content on the elastic modulus at equal strength were analyzed.The results showed that:When adding rubber particles,the strength of the concrete in the early stage (3 d and 7 d) was slower than the reference concrete,and the strength appeared more substantial growth after 7d and 14d,but the increase of strength was not obvious after 28 d.After adding a certain amount of rubber,the crack resistance of concrete has been improved to a certain extent,and the greater volume fraction of rubber particles,the integrity of the specimens was better after the compression failure.The elastic modulus of concrete showed a near-linear decreasing trend after the incorporation of crumb rubber.