剪切大变形条件下心墙沥青混凝土渗透特性研究  

Permeability study of asphalt concrete in core wall under shear large deformation conditions

作　　者：何建新[1,2,3] 李豪 杨武 刘亮[1,2,3] HE Jianxin;LI Hao;YANG Wu;LIU Liang(College of Hydraulic and Civil Engineering,Xinjiang Agricultural University,Urumqi 830052,China;Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disaster Prevention,Urumqi 830052,China;Corps Key Laboratory of Safety and Disaster Prevention of Embankment Engineering,Urumqi 830052,China)

机构地区：[1]新疆农业大学水利与土木工程学院,新疆乌鲁木齐830052 [2]新疆水利工程安全与水灾害防治重点实验室,新疆乌鲁木齐830052 [3]堤坝工程安全及灾害防治兵团重点实验室,新疆乌鲁木齐830052

出　　处：《水利学报》2024年第6期686-697,共12页Journal of Hydraulic Engineering

基　　金：新疆维吾尔自治区自然科学基金项目(2022D01A199,2021D01A100)。

摘　　要：为研究心墙沥青混凝土在大剪切变形条件下的渗透特性,基于自主研发的三轴剪切轴向渗透试验系统,对70号、110号沥青混凝土开展了不同围压、渗透压组合的三轴剪切渗透试验,并提出了基于全局优化算法的沥青混凝土渗透系数反演最优模型。试验结果表明:剪胀效应引起裂隙的张开与扩展,使沥青混凝土的渗透系数大幅增加。低围压下,轴向应变从8%增加至30%,渗透系数变化幅度可达2个数量级;应变状态和应变增量影响沥青混凝土的渗透性,渗透系数随应变场的变化而改变。压密阶段,随轴向应变的增加,体积增量比为负值,渗透系数减小。裂隙发育阶段,体积增量比为正值,渗透系数增大;围压对沥青混凝土的渗透性有显著影响。两种标号沥青混凝土试样的防渗安全轴向应变阈值在低围压时较小,随着围压的增加呈递增趋势。当围压加载至1.0 MPa,轴向应变增加至30%后,沥青混凝土的渗透系数仍满足规范要求。In order to study the permeability characteristics of asphalt concrete of heart wall under large shear deformation conditions,based on a set of triaxial shear axial seepage test system developed independently,triaxial shear seepage tests with different combinations of peripheral and permeation pressures were carried out on asphalt concrete of No.70 and No.110,and the optimal model for inversion of permeability coefficient of asphalt concrete was proposed based on the global optimization algorithm.The results show that:(1)the shear expansion effect causes the opening and expansion of cracks,which increases the permeability coefficient significantly.The axial strain of two different grades of asphalt concrete reaches 8%to 30%under different circumferential pressures,and the increase of permeability coefficient reache 2 to 3 orders of magnitude.(2)The strain state and strain increment affect the permeability of asphalt concrete,and the permeability coefficient changes with the strain field.In the compaction stage,with the increase of axial strain,the volume increment ratio is negative and the permeability coefficient decreases;in the crack development stage,the volume increment ratio is positive and the permeability coefficient increases.(3)Perimeter pressure has a significant effect on the permeability of asphalt concrete.The axial strain corresponding to the two grades of asphalt concrete specimens reaching the impermeability safety threshold is small at low perimeter pressure,and shows an increasing trend with the increase of perimeter pressure.When the perimeter pressure was loaded to 1.0 MPa and the axial strain increased to 30%,the impermeability coefficient of asphalt concrete still did not exceed the impermeability safety threshold.

关 键 词：水工沥青混凝土 大剪切变形 渗透特性 轴向应变 反演模型 

分 类 号：TM73[电气工程—电力系统及自动化]