基于旋转压实的水泥稳定再生集料设计方法

发布时间：2018-01-13 05:21

本文关键词：基于旋转压实的水泥稳定再生集料设计方法　出处：《公路交通科技》2017年10期 　论文类型：期刊论文

【摘要】：废旧水泥混凝土再生集料具有吸水率较高的特点,将其用于路面半刚性基层时传统的击实设计方法得到的水泥稳定再生集料含水量偏高,半刚性材料更加容易发生干缩开裂。为了解决这一问题,提出采用旋转压实成型方法设计水泥稳定再生集料,减小再生混合料的干缩变形,形成适用于再生集料的水泥稳定再生材料设计方法。通过室内试验对比水泥稳定再生集料在传统成型方法下与旋转压实成型方法下的配合比设计结果,试验结果表明:采用旋转压实成型法设计得到的水泥稳定再生集料的最佳含水量较传统方法得到的小;旋转压实80次的干密度指标对应于传统击实法的设计结果,但旋转压实试件的强度高于静压法试件;当水泥用量超过7%时,材料的强度主要受水泥控制,成型方法对强度影响较小;存在一个使水泥稳定再生集料的最佳含水量与最大干密度达到稳定的压实次数,可通过设置合理的压实次数,以最大干密度与抗压强度稳定状态为设计目的确定配合比。研究提出的旋转压实设计方法更适用于水泥稳定再生集料的配合比设计,可用于指导水泥稳定再生集料基层或垫层的材料设计。
[Abstract]:The recycled aggregate of waste cement concrete has the characteristics of high water absorption. The water content of cement stabilized recycled aggregate obtained by traditional compaction design method is on the high side when it is used in the semi-rigid base course of road surface. Semi-rigid materials are more prone to dry shrinkage cracking. In order to solve this problem, the rotary compaction molding method is proposed to design cement stabilized recycled aggregate to reduce the dry shrinkage deformation of recycled mixture. The design method of cement stabilized recycled material suitable for recycled aggregate was formed. The results of mix ratio design of cement stabilized recycled aggregate under traditional forming method and rotary compaction molding method were compared through laboratory tests. The experimental results show that the optimum moisture content of cement stabilized recycled aggregate designed by rotary compaction method is smaller than that obtained by traditional method. The dry density index of 80 times of rotary compaction corresponds to the design result of traditional compaction method, but the strength of rotary compaction specimen is higher than that of static compaction specimen. When the cement content exceeds 7, the strength of the material is mainly controlled by cement, and the influence of molding method on the strength is small. There is a compaction number which can make the optimum moisture content and maximum dry density of cement stabilized recycled aggregate to be stable, and the reasonable compaction times can be set. The design purpose is to determine the mixture ratio of the maximum dry density and compressive strength. The proposed design method of rotary compaction is more suitable for the design of cement stabilized recycled aggregate. It can be used to guide the material design of cement stabilized recycled aggregate base or cushion.
【作者单位】：广西桂海高速公路有限公司;广州大学;
【基金】：广东省自然科学基金项目(2014A030310272) 广州市科技计划项目(201510010110) 广西重点实验室系统性研究项目(2015ZDX007)
【分类号】：U414
【正文快照】： obtain a steady state,the stability states of maximum dry density and the compressive strength can be used asthe objective to design the mix proportion by setting the reasonable repetition times of compaction.Theproposed rotary compaction design method i

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