摘要
为研究在冻融循环条件下,强盐渍土地区砾类土路基水盐迁移规律及其对路基路用性能的影响,以察格高速公路工程为依托,采用自制冻融循环试验装置,对砾类土路基进行模拟试验。结果表明:砾类土试样经设定的冻融循环后,其含水率由路基底层向上呈"由大到小"分布,且不同的循环周期规律相同。盐分在冻融循环作用下向路基上部迁移,盐分迁移量随冻融循环周期的增加而增加。高度在10~40 cm范围内主要发生盐分迁移,高度在40~70 cm范围内主要发生盐分迁移,并出现"水去盐留"的蒸发聚盐过程。砾类土试样经冻融循环后,其回弹模量和CBR显著降低,冻融循环引起的路基次生盐渍化导致其路用性能的弱化。
In order to research water and salt migration patterns of the gravel soil subgrade in strong salined soil region under freezing and thawing cycle conditions, and its impact on subgrade pavement performance, a simulation test is made for the gravel soil subgrade with homemade freeze-thaw cycle test device, Qarhan-- Ge＇ermu Highway project as an example. The results shows that, after settings of five freeze-thaw cycles, the water content of soil sample is ＂from big to small＂ along the embankment bottom upwards, and different cycles have the same rule. Salt content increases regularly upward in the subgrade with the increase of freeze-thaw cycle. Along the height of subgrade, salt migration appears mainly in the height of 10 - 40 cm, including salt migration, water evaporation and salt crystallization occur in the height of 40 - 70 cm. Under several freezethaw cycles, the modulus of resilience and CBR of soil samples significantly reduce, and the secondary salinization caused by freeze-thaw cycle subgrade leads to the weakening of its road performance.
作者
赵爱莉
朱冬春
刘军勇
ZHAO Aili ZHU Dongchun LIU Junyong(CCC First Highway Consultants Co. , Ltd. Xi＇an 710065, China School of Highway, Chang＇an University, Xi＇an 710064, China Shanxi Key Laboratory of Road Disaster Prevention and Mitigation, Xi＇an 710065, China)
出处
《路基工程》
2017年第1期98-101,113,共5页
Subgrade Engineering
基金
中国交通建设股份有限公司
中国交建寒区旱区道路工程重点实验室资助科研项目:基于孕灾环境及成灾机理的强盐渍土地区高等级公路耐久性研究(2014-ZJKJ-PTJC07)
关键词
砾类土
冻融循环
水盐迁移
路基次生盐渍化
路用性能
gravel soil
freezing and thawing cycle
water and salt migration patterns
secondary salinizationof subgrade
pavement performance
