【作者】 王锐；

【导师】 程培峰；

【作者基本信息】 东北林业大学 ， 道路与铁道工程， 2016， 硕士

【摘要】 掌握多年冻土地区路基工后沉降变形特点,是解决多年冻土地区路基长期稳定性问题的基础,本研究以中俄原油管道漠大线林区伴行路为依托工程,选取公路沿线多年冻土区典型路基断面,采用DS18B20温度传感器和分层沉降仪对多年冻土地区路基工后温度变化和沉降变形进行观测,结合室内试验、多年冻土地温和冻土上限变化对路基沉降变形进行分析研究。结果表明：公路建成通车运行后,由于路基填土覆盖致使地温升高、冻土产生退化、冻土上限下移,导致季节活动层压缩和冻土融化压缩,是引起多年冻土区路基工后沉降的主要变形源；冻土融化压缩产生的变形所占比例最大,占总沉降量的50%；尤其是每年8-11月的4个月时间里冻土融化层压缩导致路基产生沉降变形明显,进入12月份随着季节融化层冻结和冻土上限上移稳定,路基沉降开始趋缓；在阴阳坡效应的影响下,路基融沉发育具有一定的坡向性,在一个冻融循环期内,阴坡面路基下多年冻土融化时间比阳坡面的少30d左右,阴坡面路基沉降量小于阳坡面；在相同条件下,高含冰量冻土融化压缩变形大于低含冰量冻土的融化压缩变形,填高大于3m路堤随着填土高度的增加冻土融化压缩变形增大。以现场实测数据为基础,结合室内试验数据应用ABAQUS有限元软件建立温度场和沉降变形模型,对道路在设计年限内的路基工后沉降变形情况进行预测。研究结果可为大兴安岭多年冻土地区修建公路和路基沉降变形病害分析提供理论参考。更多还原

【Abstract】 Mastering the roadbed settlement change rule after constructed is the basis of solving the problem of roadbed long-term stability in permafrost regions. This study based on the project of the china-russia crude oil pipeline great line, select the typical embankment section along the highway in permafrost regions, using DS18B20 temperature sensor and layered settlement instrument observe the temperature change and settlement change rule of roadbed after constructed in permafrost region, combined with laboratory test, permafrost geothermal and the permafrost changed study the roadbed settlement deformation. Analysis results show that after highway finishes construction and begins to operate, because of the ground temperature rise, permafrost degradation and the permafrost moving down that brought by the roadbed soil, which bring on the natural seasonal melted layer compression and permafrost melted compression that are the main cause of roadbed settlement deformation, settlement caused by permafrost melted compression is the largest, about 50%; especially on August-November 4 months, because melting permafrost layer compressed, the roadbed settlement deformation is obvious, In December as seasonal freezing and the permafrost move up stably, embankment settlement began to slow; Under the influence of the slope of shade and sunny, roadbed thawing settlement development has a certain slope tropism, in a freezing and thawing cycle period, permafrost melting time under roadbed of shade slope is about 30d less than permafrost melting time under roadbed of sunny slope, embankment settlement of the shade slope is less than embankment settlement of the sunny slope; In the same conditions, the high ice content permafrost thaw compression deformation is greater than the lower, permafrost melted compression deformation of embankments whose filling height is above 3 meters will increase with the increase of the filling height. Based on the field measured data, combined with laboratory test data apply ABAQUS finite element software to establish the temperature field and settlement deformation model, to predict roads within the period in the design of the sedimentation of roadbed deformation. The research results can provide theoretical reference of building roads and analysising roadbed settlement deformation for the permafrost regions of Greater Khingan Mountains.更多还原