微生物矿化边坡格构内植被土优先流试验及数值模拟  

Preferential Flow Experiment and Numerical Simulation on Microbial Mineralized Vegetation Soil in Slope Lattice

作　　者：李旭[1,2] 刘家庆 周成 王一冰[1] 陈群 LI Xu;LIU Jia-qing;ZHOU Cheng;WANG Yi-bing;CHEN Qun(College of Water Resource&Hydropower,Sichuan University,Chengdu,Sichuan 610065,China;CCCC National Engineering Research Center of Dredging Technology and Equipment Co.,Ltd.,Shanghai 200082,China;Guangxi Xinfazhan Communication Group Co.,Ltd.,Nanning,Guangxi 530029,China)

机构地区：[1]四川大学水利水电学院,四川成都610065 [2]中交疏浚技术装备国家工程研究中心有限公司,上海200082 [3]广西新发展交通集团有限公司,广西南宁530029

出　　处：《公路交通科技》2024年第11期104-113,150,共11页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(U2340227,U22A20602);国家重点研发计划项目(2021YFB2600100)。

摘　　要：为探究微生物矿化石漠化边坡格构内填土表层进行蓄水型植被恢复的可行性,制作纯土、表层弱矿化土、表层强矿化土、纯土+植株、表层强矿化土+植株这5种叠合式土柱试样,进行降雨-干燥试验及数值模拟。通过测试降雨阶段土柱的降雨优先流渗入、渗出量,干燥阶段表层土的裂隙发育情况及两阶段土柱内部的水力特性,探究微生物矿化格构内填土表层进行蓄水型植被恢复的降雨优先流规律。同时对土柱试件进行原型降雨-干燥数值模拟,提取土柱各深度含水率和吸力的计算值与实测值进行对比分析。结果表明:降雨阶段积雨优先蓄满蓄水孔植被土,土体的湿润饱和区也主要分布在此处,发挥了蓄水漏斗的作用,边坡格构内表层矿化+植株土柱12~32 cm深土体的平均含水率可达24%;干燥阶段表层矿化土较纯土减少约95%的裂隙,距表层2 cm处实测含水率由大到小依次为表层强矿化(25%),表层矿化+植株(22%),纯土(20.2%),植株(18%),表土硬壳层抑裂锁水效果明显,能够减少填土降雨存蓄水分的蒸发流失,增强填土的持水效果;微生物矿化石漠化边坡格构内填土表层具有良好的蓄水能力,有利于石漠化边坡的植被恢复。To explore the feasibility of water storage-based vegetation restoration at the filling surface layer in microbial mineralized rocky desertification slope lattices,5 types of composite soil column samples were created,i.e.,pure soil,weakly mineralized surface soil,strongly mineralized surface soil,pure soil with plants,and strongly mineralized surface soil with plants.These samples underwent rainfall-drying tests and numerical simulations.By measuring the infiltration and outflow of preferential rainfall during the rainfall stage,the development of surface soil cracks in drying stage,and the hydraulic characteristics inside the soil columns during both stages,the study investigated the preferential flow patterns for water storage-based vegetation restoration at the filling surface layer in microbial mineralization lattices.Simultaneously,the numerical simulations of prototype rainfall-drying processes were conducted on the soil column samples,comparing the calculated and measured values of moisture content and suction at various depths.The result indicates that during the rainfall stage,the accumulated rainwater first fills the vegetation soil with water storage holes,where the wetting saturation zone is primarily distributed.That plays the role of water reservoir funnel.For the soil columns of surface mineralization with plants,within the slope lattice,the average moisture content of soil at depth of 12-32 cm can reach up to 24%.During the drying stage,the surface mineralized soil reduces crack formation by about 95%compared with the pure soil.At 2 cm depth under the surface,the measured water contents from high to low are strongly mineralized surface(25%),surface mineralization with plant(22%),pure soil(20.2%),and plant(18%).The surface hard crust layer effectively inhibits cracking and locks in moisture,reducing the evaporation loss of stored rainfall,and enhancing the soil water retention.Meanwhile,the filling surface layer in microbial mineralized rocky desertification slope lattices exhibits the excellent w

关 键 词：道路工程 蓄水型边坡 数值分析 植被恢复 降雨-干燥试验 微生物矿化表土 

分 类 号：U416.14[交通运输工程—道路与铁道工程]