考虑双重剪切的开放系统梯形渠道Pasternak双参数冻土地基梁模型  

TWO-PARAMETER FROST-HEAVING MECHANICAL MODEL FOR TRAPEZOIDAL CANAL ON PASTERNAK FOUNDATION CONSIDERING DOUBLE SHEAR EFFECT UNDER OPEN SYSTEM CONDITION

作　　者：肖旻 王正中[2,3,4] 吴浪 杨晓松 崔浩[1] 葛建锐 XIAO Min;WANG Zheng-zhong;WU Lang;YANG Xiao-song;CUI Hao;GE Jian-rui(College of Construction Engineering,Jiangxi S&T Normal University,Nanchang,Jiangxi 330013,China;Arid and Cold Regions Water Engineering Safety Research Center,Northwest A&F University,Yangling Agricultural Hi-tech Industries Demonstration Zone,Xianyang,Shaanxi 712100,China;Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education,Northwest A&F University,Yangling Agricultural Hi-tech Industries Demonstration Zone,Xianyang,Shaanxi 712100,China;State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,CAS,Lanzhou,Gansu 730000,China;College of Water Conservancy and Construction Engineering,Tarim University,Alaer,Xinjiang 843300,China;College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China)

机构地区：[1]江西科技师范大学建筑工程学院,江西南昌330013 [2]西北农林科技大学旱区寒区水工程安全研究中心,陕西咸阳712100 [3]西北农林科技大学旱区农业水土工程教育部重点实验室,陕西咸阳712100 [4]中国科学院西北生态环境资源研究院冻土工程国家重点实验室,甘肃兰州730000 [5]塔里木大学水利与建筑工程学院,新疆维吾尔自治区,阿拉尔843300 [6]兰州理工大学能源与动力工程学院,甘肃兰州730050

出　　处：《工程力学》2024年第4期70-80,共11页Engineering Mechanics

基　　金：国家重点研发计划重点专项项目(2017YFC0405103);国家自然科学基金项目(U2003108,51641903,51869029);冻土工程国家重点实验室开放基金项目(SKLFSE201801);江西省教育厅科学技术研究项目(GJJ190621)。

摘　　要：Winkler冻土地基模型无法考虑土弹簧间相互作用,且需要预先假定切向冻结力分布。为克服这些不足之处,在现有模型基础上引入Pasternak剪切层反映冻土-衬砌间法向相互作用,引入切向弹簧组成的接触界面层反映冻土-衬砌间切向相互作用,构建考虑双重剪切的梯形渠道Pasternak双参数冻土地基模型。以塔里木灌区某渠道为例计算衬砌冻胀变形,并与材料力学法、Winkler模型计算值及观测值进行对比。结果表明:与材料力学法、Winkler模型相比,该文模型计算值更接近观测值。根据该模型估算的衬砌板易开裂范围也与灌区现场调查结果相符,表明模型适用性。通过参数研究分析了界面切向刚度kx对各处切向位移及切向冻结力分布的影响。结果表明:kx越小时,切向位移与切向冻结力趋于线性分布;kx较大时,两者均偏离线性分布且kx越大偏离越明显,线性分布假设不再适用。该模型可较充分地反映冻土与衬砌板间接触界面相互作用的基本特征,从而有效提高模型的计算精度。Existing Winkler model cannot reflect the interaction between soil springs and needs to presuppose the distribution of tangential ad-freezing force.To overcome these shortcomings,two-parameter frost-heaving mechanical model is put forward for trapezoidal canal on Pasternak foundation considering double shear effect.Normal interaction between frozen soil and concrete lining is reflected in the model through introducing a shear layer.Tangential interaction between frozen soil and concrete lining is reflected in the model including contact interfacial layer.The frost heave displacements of lining plates are computed based on a trapezoidal canal in the Tarim irrigation area,serving as a prototype.The results obtained from the presented method,material mechanics method,and Winkler model are compared with the observed values through a comprehensive analysis.The findings suggest that the results obtained through the Pasternak method exhibit a higher level of conformity with observed values,as it takes into account the reduction in frost heave force resulting from frost-induced deformation and the interaction among Winkler soil springs.Furthermore,parameter analysis for tangential displacement of each point on concrete lining under different interface shearing stiffness kx is carried out.The results show that,as kx is smaller,tangential displacement of each point on interface tends to follow linear distribution,and tangential freezing force on interface also tends to follow linear distribution;as kx is larger,tangential displacement of each point on interface deviates from linear distribution,and tangential freezing force on interface also deviates from linear distribution,so linear distribution hypothesis is no longer applicable under such condition.The model can more adequately describe the interaction between concrete lining and frozen soil on contact interface,and therefore the computational accuracy of the model is improved effectively.

关 键 词：冻土工程 渠道 冻胀 Pasternak模型 双重剪切 开放系统 

分 类 号：TV67[水利工程—水利水电工程] S277[农业科学—农业水土工程]