乳化沥青—柔性纤维改性水泥稳定碎石的路用性能研究

发布时间：2018-05-05 01:03

本文选题：乳化沥青 + 柔性纤维　；参考：《重庆交通大学》2015年硕士论文

【摘要】：半刚性基层沥青路面容易出现反射裂缝病害,为提高半刚性基层的抗裂性能,论文基于乳化沥青增柔作用和纤维阻裂增韧作用,采用乳化沥青和聚丙烯纤维两种材料对水泥稳定碎石进行改性研究。论文采用理论分析和试验研究相结合的方法,首先完成乳化沥青和柔性纤维的选型工作,确定采用慢裂快凝型阳离子乳化沥青和19mm聚丙烯纤维。通过改变乳化沥青和纤维掺量,确定CTM、CBTM-2、CBTM-3、CBTM-4和PPCBTM五种配合比。在对试验配合比进行一系列实验研究的基础上,得出以下结论:①乳化沥青的掺入会降低水泥稳定碎石的抗压强度、劈裂强度和弯拉强度,强度下降幅度与乳化沥青掺量呈正相关关系。②通过对抗压强度和劈裂强度比值的分析,得出无论水泥稳定碎石中是否加入聚丙烯纤维或乳化沥青,90d龄期时混合料的抗压强度与劈裂强度比值都稳定在8.4~9.1之间。③柔性纤维-乳化沥青水泥稳定碎石受压破坏后“破而不碎”的性质,使混合料在带缝条件下仍具有较好的延性和承载能力。④乳化沥青能够增加水泥稳定碎石的柔性,降低水泥稳定碎石的抗压回弹模量和弯拉回弹模量,抗压回弹模量降低幅度与乳化沥青掺量呈正相关关系。聚丙烯纤维的掺入能够进一步降低乳化沥青水泥稳定碎石的抗压回弹模量。⑤乳化沥青能够增加水泥稳定碎石的极限应变,3%的乳化沥青掺入能够使水泥稳定碎石的极限应变提高67.5%,有效的缓解了基层中因应变过大导致的开裂。⑥聚丙烯纤维能够有效提高乳化沥青水泥稳定碎石的弯曲韧性,且添加聚丙烯纤维后,混合料的弯曲韧性指数也明显高于普通水泥稳定碎石,韧性的提高使基层裂缝扩展需要吸收更多的能量,能够减慢基层裂缝的扩展速度。⑦聚丙烯纤维能够提高乳化沥青水泥稳定碎石的临界裂缝嘴张口位移、断裂韧度及断裂能,改善了乳化沥青水泥稳定碎石的断裂性能。⑧聚丙烯纤维能够减小乳化沥青水泥稳定碎石的温缩系数。论文采用两种不同性质材料复掺的方法对水泥稳定碎石进行改性研究,有效的改善了水泥稳定碎石变形、韧性和收缩等抗裂方面的性能,为半刚性基层材料防裂研究提供了一种新的研究思路。
[Abstract]:In order to improve the anti-cracking performance of semi-rigid asphalt pavement, this paper is based on the flexible effect of emulsified asphalt and the anti-cracking and toughening effect of fiber. The modification of cement stabilized macadam with emulsified asphalt and polypropylene fiber was studied. In this paper, the selection of emulsified asphalt and flexible fiber is completed by combining theoretical analysis and experimental study, and the slow-cracking fast-setting cationic emulsified asphalt and 19mm polypropylene fiber are selected. By changing the content of emulsified asphalt and fiber, five kinds of blending ratio of CBTM-2 / CBTM-3 and CBTM-4 and PPCBTM were determined. On the basis of a series of experimental studies on the mixture ratio of cement cement, the following conclusions are drawn: the addition of emulsified asphalt at 1: 1 can reduce the compressive strength, splitting strength and flexural strength of cement stabilized macadam. There is a positive correlation between the decrease of strength and the content of emulsified asphalt by analyzing the ratio of compressive strength and splitting strength. It is concluded that the ratio of compressive strength to splitting strength of the mixture is stable between 8.49.1 and 8.49.1, regardless of whether polypropylene fiber or emulsified asphalt is added into cement stabilized macadam for 90 days. 3. 3 flexible fiber-emulsified asphalt cement stabilized macadam under compression. The nature of "breaking but not breaking" after destruction, The mixture still has good ductility and bearing capacity under the condition of joint. 4 emulsified asphalt can increase the flexibility of cement stabilized macadam and reduce the modulus of compressive resilience and flexural elasticity of cement stabilized macadam. The decrease of modulus of compressive resilience is positively correlated with the content of emulsified asphalt. Polypropylene fiber incorporation can further reduce the compressive resilience modulus of emulsified asphalt cement stabilized macadam .5 emulsified asphalt can increase the limit strain of cement stabilized macadam by 3% emulsified asphalt can make cement stabilized macadam The ultimate strain is increased by 67.5%, which effectively alleviates the cracking of 6. 6 polypropylene fiber in the base course caused by excessive strain. It can effectively improve the flexural toughness of emulsified asphalt cement stabilized macadam. After adding polypropylene fiber, the flexural toughness index of the mixture is obviously higher than that of the ordinary cement stabilized macadam. With the increase of toughness, the crack propagation of the base course needs to absorb more energy. 7. Polypropylene fiber can improve the critical crack mouth opening displacement, fracture toughness and fracture energy of emulsified asphalt cement stabilized macadam. The fracture performance of emulsified asphalt cement stabilized macadam is improved. 8. Polypropylene fiber can reduce the temperature shrinkage coefficient of emulsified asphalt cement stabilized macadam. In this paper, two kinds of different materials are used to modify the cement stabilized macadam, which can effectively improve the crack resistance, such as deformation, toughness and shrinkage of cement stabilized macadam. It provides a new research idea for anti-crack research of semi-rigid base material.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414

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