重塑红黏土固结变形影响因素分析

发布时间：2018-01-10 12:25

  本文关键词：重塑红黏土固结变形影响因素分析　出处：《公路》2017年04期 　论文类型：期刊论文

  更多相关文章： 重塑红黏土 固结变形 压缩系数 干湿循环

【摘要】：基于一维室内固结试验,分析了初始状态和干湿循环状态下红黏土固结变形特性,并对固结试验过程中的保湿方法进行了改进。研究结果表明,压缩试验的保湿方法建议采用预先补水+湿毛巾覆盖的措施,需要补充水分的多少根据散失的水量来定。当含水率介于最佳含水率-2%~最佳含水率之间,孔隙比、压缩变形系数、压缩系数变化幅度不大。当含水率大于最佳含水率后,孔隙比、压缩变形系数、压缩系数随含水率的增加变化幅度较大。从控制路基工后沉降的角度考虑,建议路基压实时的含水率介于最佳含水率-2%~最佳含水率之间。压实红黏土应力~应变关系可用ε/p=Kp~n式来表达。干湿循环后红黏土压缩系数明显比初始状态的压缩系数要大,且随着循环次数的增加,压缩系数增大,前3次循环压缩系数增加较大,第4次和第5次循环压缩系数趋于稳定。建议在路基沉降计算中采用长期压缩系数a_(1-2)指标(即第4次或第5次循环的压缩系数),使得计算结果更加符合实际情况。
[Abstract]:Based on one-dimensional laboratory consolidation tests, the consolidation deformation characteristics of red clay under initial state and dry wet cycle state are analyzed, and the moisturizing method during consolidation test is improved. The moisturizing method of compression test suggests that the measure of pre-hydrating wet towel covering should be adopted, and the amount of water supply should be determined according to the amount of lost water. When the moisture content is between the optimum moisture content and the optimum moisture content, the moisture content is between the optimum moisture content and the optimum moisture content. The void ratio, compression deformation coefficient and compression deformation coefficient change little. When the water content is larger than the optimum water content, the void ratio and the compression deformation coefficient. The compression coefficient varies greatly with the increase of moisture content. From the point of view of controlling the settlement of roadbed after construction. It is suggested that the moisture content of embankment is between the optimum moisture content of -2 and the optimum moisture content. The stress-strain relationship of compacted red clay can be expressed by 蔚 / ppKpPNs formula. The compression coefficient of red clay is clear after dry and wet cycle. The explicit compression coefficient is larger than the initial state. With the increase of cycle times, the compression coefficient increases, and the first three cycles increase greatly. The compression coefficients of the 4th and 5th cycles tend to be stable. It is suggested that the long-term compression coefficients a / 1 / 2 (i.e. the compression coefficients of the 4th or 5th cycles) should be used in the calculation of subgrade settlement. The calculation results are more in line with the actual situation.
【作者单位】： 贵州大学土木工程学院;
【基金】：国家自然科学基金项目,项目编号51368010,51668011 贵州省科技支撑计划项目,黔科合支撑[2016]2005 贵州科技厅-贵州大学联合资金项目,黔科合LH字[2014]7663
【分类号】：U416.16
【正文快照】： 红黏土主要分布于我国南方地区,由于红黏土表1　红黏土基本物理指标具有高液限、高塑性和高含水率等特点,红黏土路基按公路土工0.075~产生一些病害[1],究其原因在干旱季节红黏土失水0.075mm/%0.002mm/%试验规程(JTG0.002mm/%收缩,雨季又吸水饱和膨胀,这样往复的作用将导致E4，

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