毛细阻滞层防治季节冻土路基覆盖效应试验研究  

Experimental study on effect of capillary blocking layer in preventing and controlling subgrade covering of seasonal frozen soil

作　　者：赵培琳 张明礼[1,2] 冯微 冯德刚 闫欣晨 刘岳峰 ZHAO Peilin;ZHANG Mingli;FENG Wei;FENG Degang;YAN Xinchen;LIU Yuefeng(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Western Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China;Bridge and Tunnel Engineering Co.,Ltd.,CCCC Third Highway Engineering Co.,Ltd.,Beijing 100012,China)

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050 [2]兰州理工大学西部土木工程防灾减灾教育部工程研究中心,甘肃兰州730050 [3]中交三公局桥梁隧道工程有限公司,北京100012

出　　处：《长沙理工大学学报(自然科学版)》2025年第1期28-39,共12页Journal of Changsha University of Science & Technology:Natural Science

基　　金：国家自然科学基金项目(41961010);中科院西部之光“西部青年学者”项目(23JR6KA027);甘肃省杰出青年基金项目(24JRRA167);甘肃省重点研发计划(25YFFA012)。

摘　　要：【目的】季节冻土区公路路基因季节性温度变化使路基中的水分向上迁移,导致水分在封闭覆盖层下聚集产生覆盖效应,进而引起路基冻胀、融沉、路面开裂、道路翻浆等工程病害。为了有效抑制封闭覆盖层下覆盖效应的产生,以季节冻土区气候特征为背景,开展了室内一维土柱试验。【方法】通过设计两组冻融循环条件下的室内路基模型试验,探究有、无毛细阻滞层季节冻土区路基内部的水热变化规律,验证毛细阻滞层对季节冻土区公路路基覆盖效应的防治效果。【结果】在季节性温变导致的冻融循环条件下,传统路基浅层2.5、5.0 cm深度范围内的土体含水率随冻融循环次数的增加而不断增大,最大液态水含量增加量达5.8个百分点,覆盖效应明显;毛细阻滞层路基在浅层2.5 cm深度处的土体含水率随冻融循环次数的增加水分累积量仅为1.8个百分点,且经历3个循环后其他深度的最大液态水含量与含水率累积量均略有减小,整体含水率远小于无毛细阻滞层路基的。【结论】毛细阻滞层的设置能够明显抑制覆盖层下浅层土体含水率的增加和累积,且对维持季节冻土区路基土体水分场稳定具有重要作用。[Purposes]The seasonal temperature change of highway subgrade in the seasonal frozen soil area causes the upward migration of water in the subgrade,making water accumulate under the closed covering layer and resulting in the covering effect,which then induces the subgrade frost heave,melt settlement,pavement cracking,frost boiling of roads,and other engineering diseases.In order to effectively suppress the covering effect under the closed covering layer,a laboratory one-dimensional soil column test was carried out based on the climatic characteristics of the seasonal frozen soil area.[Methods]Through the design of two sets of laboratory subgrade model tests under the condition of freeze-thaw cycles,the hydrothermal variation rule in the subgrade with and without capillary blocking layer in the seasonal frozen soil area was explored,and the prevention and controlling effect of capillary blocking layer on the covering effect of highway subgrade in the seasonal frozen soil area was verified.[Findings]Under the freeze-thaw cycle conditions caused by seasonal temperature change,the volume water content of soil in the traditional shallow subgrade at a depth of 2.5 and 5.0 cm increases with the increase in the number of freeze-thaw cycles,and the maximum liquid water content increases by 5.8 percentage points,which shows obvious covering effect.The soil water content at the shallow capillary blocking layer at a depth of 2.5 cm is only 1.8 percentage points with the increase in the number of freeze-thaw cycles,and the maximum liquid water content and cumulative water content at other depths decrease slightly after the three cycles.The overall water content is much smaller than that of the subgrade without the capillary blocking layer.[Conclusions]The installation of a capillary blocking layer can significantly inhibit the increase and accumulation of water content in shallow soil under the covering layer and play an important role in maintaining the stability of the water field of subgrade soil in the seasonal frozen soi

关 键 词：毛细阻滞效应 季节冻土 冻融循环 公路路基 覆盖效应 水热变化 

分 类 号：U419.92[交通运输工程—道路与铁道工程]