疏水层状土体Green-Ampt模型的改进及堵塞毛细运移的性能演化  

Improved Green-Ampt Model for Hydrophobic Layered Soil and the Performance Evolution of Blocing Capillary Migration

作　　者：牛泽林 马德良[1] 冯怀平[1] 韩仲 NIU Zelin;MA Deliang;FENG Huaiping;HAN Zhong(State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Jointly Built by the Ministry and the Province of Shijiazhuang Tiedao University,Shijiazhuang,Hebei 050043,China;School of Civil Engineering,Wuhan University,Wuhan,Hubei 430072,China)

机构地区：[1]石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点试验室,河北石家庄050043 [2]武汉大学土木工程学院,湖北武汉430072

出　　处：《水利与建筑工程学报》2025年第1期161-169,共9页Journal of Water Resources and Architectural Engineering

基　　金：中央引导地方项目(236Z5409G);国家基金青年项目(52308458)。

摘　　要：为进一步研究疏水剂的阻水性能,采用正辛基三乙氧基硅烷对粉土进行处理,得到疏水性粉土,通过中间设置疏水层的一维土柱试验,分析疏水层厚度、硅烷含量、土样干密度等因素对毛细水上升的影响。提出一种改进的Green-Ampt模型来描述疏水性土体的毛细水上升过程,并利用修正模型得到的土体导水率对试验结果进行解释。结果表明:土体干密度对毛细水上升有明显影响,随干密度增加,毛细水上升速度越慢,当干密度较小时,由于水分和上部荷载的作用而产生的孔隙水压力,会迫使防水层失效;疏水层厚度对阻水效果影响不大,但随着厚度增加水分迁移速度变慢并且明显延迟水分到达土样顶部时间;硅烷含量是抑制毛细水上升的关键因素,随着硅烷含量的增加防水层阻水能力增强。而对于1.0%含量的防水层的土样,不管疏水层厚度、干密度如何均能阻止毛细上升,并且10 mm的疏水层就足够有效。To further investigate the water blocking performance of hydrophobic agents,n-octyltriethoxysilane was used to treat the clay to obtain hydrophobic clay.Through one-dimensional soil column tests with a hydrophobic layer in the middle,the influence of factors such as hydrophobic layer thickness,silane content,and soil sample dry density on capillary water rise was analyzed.A modified Green Ampt model was proposed to describe the capillary water rise in hydrophobic soils,and the experimental results were explained using the soil hydraulic conductivity obtained from the modified model.The results indicate that the dry density of soil has a significant impact on the rise of capillary water.As the dry density increases,the capillary water rises slower.When the dry density is low,the pore water pressure generated by moisture and upper load will force the waterproof layer to fail.The thickness of the hydrophobic layer has little effect on the water blocking effect,but as the thickness increases,the water migration rate slows down and the time for water to reach the top of the soil sample is significantly delayed.For soil samples with a 1.0% waterproof layer,regardless of the thickness and dry density of the hydrophobic layer,capillary rise can be prevented,and a 10 mm hydrophobic layer is sufficient for effectiveness.

关 键 词：疏水剂 阻水性能 土柱试验 防水层 

分 类 号：U416[交通运输工程—道路与铁道工程]