水泥稳定碎石基层耐久抗裂的振动搅拌技术的研究与应用

发布时间：2018-06-18 04:53

本文选题：道路 + 水泥稳定碎石　；参考：《长安大学》2015年硕士论文

【摘要】：在公路、机场等建设中,水泥稳定碎石的质量直接影响着道路基础层的施工质量与寿命。我国稳定土基层耐久性差和裂缝问题已经存在了多年,其中一个主要原因是搅拌的稳定土不均匀。针对行业存在的这一问题,论文提出采用振动搅拌水泥稳定碎石,来激发水泥稳定碎石混合料本身的潜能,提高路面基层的耐久性与抗裂性能。论文采用理论分析与试验研究相结合的研究方法,对振动搅拌水泥稳定碎石技术进行了理论分析、实验室试验研究与工程应用的测试分析与研究,证明了采用振动搅拌水泥稳定碎石技术的可行性。论文将搅拌工作装置的物理模型与扩散方程的数学模型相结合,对连续式搅拌机械的工作机构与介质间的相互作用过程进行综合模拟与研究,得到了搅拌过程混合料均匀性变化的数学表达式,揭示了搅拌过程中混合物均匀性与搅拌时间、搅拌参数与搅拌速度系数之间变化规律,为采用振动搅拌技术来强化扩散运动,以及振动与强制搅拌相结合的振动搅拌方案提供了理论依据。实验室设计的双重振动机构,在槽体振动强度不大的情况下,搅拌叶片处于共振状态,较好地解决了机器工作耐久性与工作机械所需振动参数间的矛盾,能够拌出符合国家标准的稳定土和水泥混凝土,但搅拌过程中对流运动不够强烈,合理的办法是采用强制搅拌与振动搅拌相结合的双卧轴连续式振动搅拌方案。现场使用与测试表明,振动搅拌水泥稳定碎石能把混合料中的水和水泥团、灰团振碎,使其均匀分布在混合料中,包裹了骨料,搅拌的稳定土质量稳定,耐久性提高;节约水泥,为用户创造了额外的效益;运输、摊铺过程中混合料不离析,施工性能好,混合料取芯容易,密实性好;路面基层裂缝大幅度减少。研究证明,振动搅拌技术通过振动强化加工过程,减少水泥用量,改善水泥稳定碎石的微观均匀性与结构,发挥材料本身潜能,不仅能提高水泥稳定碎石基层的强度与耐久性,而且在运输摊铺过程中不离析,大幅度减少了后期的裂缝现象;同时,振动搅拌技术的使用成本低,使用方便,便于施工,节约水泥,对材料没有负作用,符合低碳经济的要求,是提高路面基层耐久抗裂性能与寿命的一种新方法和新技术。
[Abstract]:In the construction of highway and airport, the quality of cement stabilized macadam directly affects the construction quality and service life of road foundation layer. The problem of durability and crack of stabilized soil base in China has existed for many years, and one of the main reasons is the uneven mixing of stabilized soil. Aiming at this problem, the paper proposes to use vibration agitation cement stabilized macadam to stimulate the potential of cement stabilized macadam mixture and to improve the durability and crack resistance of pavement base. In this paper, the theoretical analysis, laboratory test and engineering application of vibration-agitated cement-stabilized crushed stone technology are studied by combining theoretical analysis with experimental research. The feasibility of using vibratory mixing cement stabilized macadam technology is proved. In this paper, the physical model of agitator and the mathematical model of diffusion equation are combined to simulate and study the interaction process between the working mechanism and the medium of the continuous mixer. The mathematical expression of mixture uniformity in mixing process is obtained, and the variation law of mixture uniformity and mixing time, stirring parameters and stirring velocity coefficient is revealed. And the vibration mixing scheme combining vibration and forced stirring provides the theoretical basis. The dual vibration mechanism designed in the laboratory is in the resonance state under the condition that the vibration intensity of the tank body is not large, which resolves the contradiction between the working durability of the machine and the vibration parameters required by the working machinery. The stable soil and cement concrete can be mixed with the national standard, but the convection motion is not strong enough in the mixing process. The reasonable method is to adopt the continuous vibration mixing scheme of double horizontal axis combined with forced stirring and vibration stirring. The field application and test show that vibrating mixing cement stabilized macadam can shatter the water and cement mass in the mixture, make it distribute uniformly in the mixture, wrap the aggregate, the quality of the mixing stabilized soil is stable, and the durability is improved. It saves cement and creates extra benefit for users. In the process of transportation and spreading, the mixture is not segregated, the construction performance is good, the mixture is easy to take core, and the compactness is good; the cracks of the pavement base are greatly reduced. It is proved that vibration agitation technology can not only improve the strength and durability of cement stabilized macadam base, but also improve the micro uniformity and structure of cement stabilized macadam by strengthening the processing process of cement by vibration, so as to give full play to the potential of the material itself. Moreover, in the course of transportation and paving, the phenomenon of cracks in the later period is greatly reduced by no segregation in the course of transportation and spreading. At the same time, the use of vibration mixing technology is low in cost, convenient in use, convenient in construction, saving cement, and has no negative effect on the material. According to the requirement of low carbon economy, it is a new method and new technology to improve the durability and life of pavement base.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U416.214

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