冻融循环作用下多工况粗颗粒硫酸盐渍土路基变形特性  

Deformation characteristics of coarse-grained sulfate saline soil roadbed under multiple working conditions under freeze-thaw cycles

作　　者：刘伟[1,2] 杨晓华[2] 张莎莎[2] LIU Wei;YANG Xiao-hua;ZHANG Sha-sha(Department of Architecture and Environmental Engineering,Taiyuan University,Taiyuan 030032,Shanxi,China;School of Highway,Chang'an University,Xi'an 710064,Shaanxi,China)

机构地区：[1]太原学院建筑与环境工程系,山西太原030032 [2]长安大学公路学院,陕西西安710064

出　　处：《长安大学学报(自然科学版)》2025年第1期13-23,共11页Journal of Chang’an University(Natural Science Edition)

基　　金：中国中铁重大科研项目(2017-重大-11-04);山西省高等学校科技创新项目(2022L592)。

摘　　要：为了深入研究粗颗粒硫酸盐渍土路基在冻融循环作用下的变形特性,根据实际环境条件,针对现场粗颗粒硫酸盐渍土,开展封闭状态、降水及地下水盐补给3种工况、7个冻融循环周期的粗颗粒硫酸盐渍土路基变形模型试验,得到冻融循环过程中路基温度及变形的变化规律。结合路基中含水率和含盐量的变化,对比分析冻融循环作用下降水、地下水盐补给对粗颗粒盐渍土路基变形的影响,提出相应路基的变形率。研究结果表明:在7个冻融循环周期过程中,3种工况粗颗粒硫酸盐渍土路基不同深度处土体的温度均呈周期性变化,且深度越大,土体温度的变化幅度越小;封闭状态和地下水盐补给条件下路基在周期末的总变形随冻融循环次数的增加,先增大后逐渐趋于稳定,而降水条件下路基在周期末的总变形呈先增大后减小的趋势;各工况下路基的变形均表现为盐胀累加,且封闭状态、降水及地下水盐补给工况下路基的最大变形量分别为0.915、12.385、0.957 mm;降水条件下路基的最终总变形量为封闭状态下路基最终总变形量的10.5倍,降水对该粗颗粒盐渍土路基变形的影响较大;封闭状态和地下水盐补给条件下路基在周期内的最大盐胀变形量分别为0.402、0.421 mm,两者的最终总变形量分别为0.603、0.611 mm,地下水盐补给对该粗颗粒盐渍土路基的变形影响相对较小;3种工况下路基的最大变形率分别为0.153%、2.064%、0.160%。In order to further study the deformation characteristics of coarse-grained sulfate saline soil roadbed underfreeze-thaw cycles,based on actual environmental conditions,deformation model tests were conducted on the roadbedof coarse-grained sulfate saline soil on site under three working conditions,closed state,precipitation,and supply ofgroundwater and salt.Seven freeze-thaw cycles were conducted for each working condition.The variation patterns oftemperature and deformation of the roadbed during freeze-thaw cycles were obtained.Taking into account the changesin moisture and salt content in the roadbeds,the effects of precipitation and supply of groundwater and salt underfreeze-thaw cycles on the deformation of coarse-grained saline soil roadbed were compared and analyzed,and thedeformation rates of the corresponding roadbeds were proposed.The results show that during 7 cycles of freeze-thawcycles,the temperature of the soil at different depths of the coarse-grained sulfate saline soil roadbed under threeworking conditions shows periodic changes,and the larger the depth,the smaller the magnitude of the temperaturechange in the soil.Under closed state and supply of groundwater and salt conditions,the total deformation of theroadbed at the end of the freeze-thaw cycle increases first and then gradually stabilizes with the increase of freeze-thawcycles.However,under precipitation conditions,the total deformation of the roadbed at the end of the freeze-thaw cycleshows a trend of increasing first and then decreasing.The deformation of the roadbed under each test condition ismanifested as the accumulation of salt expansion.The maximum deformation of the roadbed under the three workingconditions of closed state,precipitation,and supply of groundwater and salt are 0.915,12.385,0.957 mm,respectively.The final total deformation of the roadbed under precipitation conditions is 10.5 times that of the roadbedin a closed state,and the precipitation has a significant impact on the deformation of the coarse-grained saline soilro

关 键 词：道路工程 粗颗粒硫酸盐渍土 试验研究 冻融循环 变形 封闭状态 降水 地下水盐补给 

分 类 号：U416.1[交通运输工程—道路与铁道工程]