换填法抑制季节冻土区铁路路基冻胀效果分析
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摘要
以沈哈线路基A、B组填料为研究对象,采用室内冻胀试验,研究粉黏粒含量对其冻胀特性的影响。试验表明:路基填料的冻胀系数随粉黏粒含量增加而增加,且增幅逐渐增大;结合沈哈线路基基床厚度及沿线最大冻深,为保证路基不产生冻胀破坏,应确保换填用路基A、B组填料中不含有粉黏粒。采用非稳态相变温度场的数学模型和热弹塑性冻胀模型,进行沈哈线换填试验段冻土路基冻融过程温度场及冻胀应力、变形场计算分析。结果表明:天然地面下2m左右为冻融活动层,是诱发路基土体冻胀的主要因素;用非冻胀性A、B组填料换填基床厚度范围内的冻胀性土层后,路堤填筑土体无冻胀变形产生,路基中的拉应力(拉应变)区域外移到距离路堤坡脚4m以外的天然地表下土体,大大减弱了对路堤的破坏作用,计算结果与实际情况相符。
A,B class filler obtained along Shenyang-Harbin Railway was taken as the research object.The effect of silt and clay particle content on the frost heaving characteristics of filling material was investigated with indoor freezing and heaving experiments.The results show that the frost heaving coefficient of the roadbed filling increases with the increase of silt and clay particle content,and the amplitude increases gradually.To prevent the existing subgrade from frost heaving damage,it is necessary to make A,B class filler not contain silt and clay particle,considering the thickness of subgrade bed and the maximum frozen depth of Shenyang-Harbin Railway.The mathematical model of the unsteady phase transition temperature field and the thermo-elasto-plastic frost heave model are employed to calculate and analyze the temperature field,the frost heave stress and the deformation field of the frozen soil embankment during its frost heaving process in the replacing soil test section of Shenyang-Harbin Railway.Results show that about 2 m below the natural ground surface is the freezing-thawing active layer,which is the main factor to induce the frost heave of the subgrade.The embankment will be absent from frost heave deformation if the soil with frost heave sensitivity is excavated and then the non-frost-heave A,B group material is filled in the excavated subgrade bed.Moreover,the tensile stress(tensile strain) zone of the roadbed shifts more than 4 m outward from the toe of the side slopes,reducing the damage to the embankment greatly and enhancing the stability of the roadbed.The calculation results agree well with the actual situation.
A,B class filler obtained along Shenyang-Harbin Railway was taken as the research object.The effect of silt and clay particle content on the frost heaving characteristics of filling material was investigated with indoor freezing and heaving experiments.The results show that the frost heaving coefficient of the roadbed filling increases with the increase of silt and clay particle content,and the amplitude increases gradually.To prevent the existing subgrade from frost heaving damage,it is necessary to make A,B class filler not contain silt and clay particle,considering the thickness of subgrade bed and the maximum frozen depth of Shenyang-Harbin Railway.The mathematical model of the unsteady phase transition temperature field and the thermo-elasto-plastic frost heave model are employed to calculate and analyze the temperature field,the frost heave stress and the deformation field of the frozen soil embankment during its frost heaving process in the replacing soil test section of Shenyang-Harbin Railway.Results show that about 2 m below the natural ground surface is the freezing-thawing active layer,which is the main factor to induce the frost heave of the subgrade.The embankment will be absent from frost heave deformation if the soil with frost heave sensitivity is excavated and then the non-frost-heave A,B group material is filled in the excavated subgrade bed.Moreover,the tensile stress(tensile strain) zone of the roadbed shifts more than 4 m outward from the toe of the side slopes,reducing the damage to the embankment greatly and enhancing the stability of the roadbed.The calculation results agree well with the actual situation.
引文
[1]李建宇,刘建坤,孙继彪.包兰线路基土冻胀特性试验分析[J].铁道建筑,2007,47(12):72-74.(LI Jianyu,LIU Jiankun,SUN Jibiao.Experimental Analysis on Frost Heaving Property of Baotou to Lanzhou Rail-way Subgrade[J].Railway Engineering,2007,47(12):72-74.in Chinese)
[2]田亚护.动、静荷载作用下细粒土冻结时水分迁移与冻胀特性实验研究[D].北京:北京交通大学,2008.(TIAN Yahu.The Experimental Study on Moisture Migration and Frost Action of Fine-Grained Soils during Freezingunder Dynamic and Static Loading[D].Beijing:Beijing Jiaotong University,2008.in Chinese)
[3]彭丽云,刘建坤,田亚护.粉质黏土的冻胀特性研究[J].水文地质工程地质,2009,36(6):62-67.(PENG Liyun,LIU Jiankun,TIAN Yahu.Study on Frost Heaving Property of Silty Clay[J].Hydrogeology&En-gineering Geology,2009,36(6):62-67.in Chinese)
[4]邴文山.公路路面防冻层设计理论的探讨[J].冰川冻土,1984,6(3):69-76.(BING Wenshan.Discussion on Design of Frost-Preventing Layer for Pavements in Districts of Frozen Ground[J].Journal of Glaciology and Geocryology,1984,6(3):69-76.in Chinese)
[5]谷宪明.季冻区道路冻胀翻浆机理及防治研究[D].长春:吉林大学,2007.(GU Xianming.Study on Mechanism and Prevention of Frost Heaving and Frost Boiling in Seasonally Frozen Road[D].Changchun:Jilin University,2007.in Chinese)
[6]叶阳升,王仲锦,程爱君,等.路基的填料冻胀分类及防冻层设置[J].中国铁道科学,2007,28(1):1-7.(YE Yangsheng,WANG Zhongjin,CHENG Aijun,et al.Frost Heave Classification of Railway Subgrade FillingMaterial and the Design of Anti-Freezing Layer[J].China Railway Science,2007,28(1):1-7.in Chinese)
[7]许健,牛富俊,林战举.高温高含冰量冻土路基流变特性数值分析[J].中国铁道科学,2008,29(5):13-19.(XU Jian,NIU Fujun,LIN Zhanju.Numerical Analysis of Rheological Character of Embankment with Warm andIce-Rich Frozen Soil[J].China Railway Science,2008,29(5):13-19.in Chinese)
[8]铁道第一勘查设计院.哈大线沈哈段季节性冻土路基防护设计[R].西安:铁道第一勘察设计院,2007.
[9]铁道第一勘查设计院.沈哈线D3K690+700～D3K693+000地基处理及路堤坡面防护工程地质勘察报告[R].西安:铁道第一勘察设计院,2006.
[10]朱临楠.高原冻土区不同下垫面的附面层研究[J].冰川冻土,1988,10(1):8-14.(ZHU Linnan.Study of the Adherent Layer on Different Types of Ground in Permafrost Regions on the Qinghai-Ti-bet Plateau[J].Journal of Glaciology and Geocryology,1988,10(1):8-14.in Chinese)
[11]王钧.中国地温分布的基本特征[M].北京:地震出版社,1990.
[12]徐学组,陶兆祥,傅素兰.典型融冻土的热学性质[C]//中国科学院兰州冰川冻土沙漠所集刊(第2号).北京:科学出版社,1981:104-112.(XU Xuezu,TAO Zhaoxiang,FU Sulan.The Thermodynamics Properties of Typically Thaw and Frozen Soil[C]//Memory of Lanzhou Institute of Glaciology and Geocryology,Chinese Academy of Sciences(No.2).Bei-jing:Science Press,1981:104-112.in Chinese)
[13]童长江,管枫年.土的冻胀与建筑物冻害防治[M].北京:水利电力出版社,1985.
[2]田亚护.动、静荷载作用下细粒土冻结时水分迁移与冻胀特性实验研究[D].北京:北京交通大学,2008.(TIAN Yahu.The Experimental Study on Moisture Migration and Frost Action of Fine-Grained Soils during Freezingunder Dynamic and Static Loading[D].Beijing:Beijing Jiaotong University,2008.in Chinese)
[3]彭丽云,刘建坤,田亚护.粉质黏土的冻胀特性研究[J].水文地质工程地质,2009,36(6):62-67.(PENG Liyun,LIU Jiankun,TIAN Yahu.Study on Frost Heaving Property of Silty Clay[J].Hydrogeology&En-gineering Geology,2009,36(6):62-67.in Chinese)
[4]邴文山.公路路面防冻层设计理论的探讨[J].冰川冻土,1984,6(3):69-76.(BING Wenshan.Discussion on Design of Frost-Preventing Layer for Pavements in Districts of Frozen Ground[J].Journal of Glaciology and Geocryology,1984,6(3):69-76.in Chinese)
[5]谷宪明.季冻区道路冻胀翻浆机理及防治研究[D].长春:吉林大学,2007.(GU Xianming.Study on Mechanism and Prevention of Frost Heaving and Frost Boiling in Seasonally Frozen Road[D].Changchun:Jilin University,2007.in Chinese)
[6]叶阳升,王仲锦,程爱君,等.路基的填料冻胀分类及防冻层设置[J].中国铁道科学,2007,28(1):1-7.(YE Yangsheng,WANG Zhongjin,CHENG Aijun,et al.Frost Heave Classification of Railway Subgrade FillingMaterial and the Design of Anti-Freezing Layer[J].China Railway Science,2007,28(1):1-7.in Chinese)
[7]许健,牛富俊,林战举.高温高含冰量冻土路基流变特性数值分析[J].中国铁道科学,2008,29(5):13-19.(XU Jian,NIU Fujun,LIN Zhanju.Numerical Analysis of Rheological Character of Embankment with Warm andIce-Rich Frozen Soil[J].China Railway Science,2008,29(5):13-19.in Chinese)
[8]铁道第一勘查设计院.哈大线沈哈段季节性冻土路基防护设计[R].西安:铁道第一勘察设计院,2007.
[9]铁道第一勘查设计院.沈哈线D3K690+700～D3K693+000地基处理及路堤坡面防护工程地质勘察报告[R].西安:铁道第一勘察设计院,2006.
[10]朱临楠.高原冻土区不同下垫面的附面层研究[J].冰川冻土,1988,10(1):8-14.(ZHU Linnan.Study of the Adherent Layer on Different Types of Ground in Permafrost Regions on the Qinghai-Ti-bet Plateau[J].Journal of Glaciology and Geocryology,1988,10(1):8-14.in Chinese)
[11]王钧.中国地温分布的基本特征[M].北京:地震出版社,1990.
[12]徐学组,陶兆祥,傅素兰.典型融冻土的热学性质[C]//中国科学院兰州冰川冻土沙漠所集刊(第2号).北京:科学出版社,1981:104-112.(XU Xuezu,TAO Zhaoxiang,FU Sulan.The Thermodynamics Properties of Typically Thaw and Frozen Soil[C]//Memory of Lanzhou Institute of Glaciology and Geocryology,Chinese Academy of Sciences(No.2).Bei-jing:Science Press,1981:104-112.in Chinese)
[13]童长江,管枫年.土的冻胀与建筑物冻害防治[M].北京:水利电力出版社,1985.
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