【作者】 祝发珠；

【导师】 朱涵；

【作者基本信息】 天津大学 ， 结构工程， 2007， 硕士

【摘要】 橡胶集料混凝土作为一种新型的混凝土材料,具有低弹性模量、大变形、高阻尼、能量耗散多及良好的抗裂性能等优点。目前国内对橡胶集料混凝土的研究主要集中在力学性能方面,耐久性研究方面的成果甚少。在我国北方寒冷的冬季在道路上使用除冰盐,对混凝土的耐久性造成了极大的危害;因此,有必要研究橡胶集料混凝土在除冰盐环境下的性能,为将来的广泛应用和结构的耐久性设计提供可靠的实验依据。为研究橡胶集料混凝土抵抗盐冻破坏的性能,本文考虑了5种影响因素,即橡胶集料掺量、实验室养护条件、水灰比、矿物掺合料和含气量。在4%NaCl溶液中冻融一定循环次数后,收集剥落物来测试剥落性能;同时跟踪测试混凝土的相对吸水量和相对动弹性模量。试验结果显示,当橡胶集料体积掺量在12%左右时,改善盐冻破坏的效果比较好,跟引气4%的普通混凝土的抗盐冻剥落效果相当。此外,盐冻对橡胶集料混凝土的力学性能有劣化作用。根据现有的含气量测试手段,对橡胶集料在混凝土中的引气作用进行了试验研究,并探讨了橡胶集料对混凝土抵抗盐冻破坏的机理。试验证实橡胶集料的确可以在混凝土中起到固体引气剂的作用,并且这种引气效果随着橡胶掺量增加而增大。橡胶的掺入,改善了混凝土的微观结构,提高了抗渗透性能,从而提高了耐久性能。更多还原

【Abstract】 Crumb rubber concrete (CRC), which is known as a new concrete material, characterized by low young’s modulus、large deformation、high energy disspation and extremely good crack resistance. Now the mechanics function is the greatly part of study in our country,and there is almost nothing about durability of the crumb rubber concrete.it is essential to study the function of the crumb rubber concrete under deicer environment which will do badly harm to concrete’s durability when the deicer is used on the road in cold winter of our country’s northern region.This paper considere five factors that are the contents of crumb rubber volume ratio、the curing condition、the water cement ratio、mineral material ratio and air content to research the performance of deicer - scaling resistance of crumb rubber conrete. CRC specimens submerged with the solution of 4% NaCl, after certain freeze-thaw cycles, the scaled mass which is the response of the deicer-scaling resistance is collected; at the same time, relative water contents and dynamic modulus of elasticity are tested. The results show that the crumb rubber can improve the behavior to resist the deicer-scaling; and when the volume ratio is about 12%, the effect is evident which is comparative to the plain concrete added air of 4%. The freeze-thaw cycle will reduce concrete’s mechanics performance, and with the increase of this cycles the extent of reduce must become large.According to existing test means of air content, the effect of air content aroused by adding crumb rubber into concrete is studied; and based on the experimental result, it is discussed the mechanism of the deicer-scaling resistance of crumbrubberconcrete. The result indicates that the crumb rubber can be used as a solid air-entraining additive, and when the ratio of crumb rubber increasing, the effect will be more clearly. Adding crumb rubber can help improve the microstructure and the permeability of concrete, so untimately heighten the material durability.更多还原