涩宁兰复线多年冻土地段治理方案研究

Schematic Studies of Frozen Soil Treatment in Se-Ning-Lan Second Gas Pipeline Project

主要介绍了涩宁兰复线橡皮山和拉脊山地段多年冻土对管道的危害及其治理方案。对冻土的形成机理和破坏机理进行了分析,得到了不同类型土壤的冻胀量与冻结深度关系。基于有限元分析软件对管道遭受冻融作用进行力学分析,确定冻土对管道安全的危害程度。通过对现场实地调研和分析研究,提出了针对该地区的多年冻土危害的防治方案,即采用袋装砂置换冻土的稳管方案,该方案不仅解决了冬季冻涨问题,而且解决了夏季融沉对管道的影响,同时节约了施工成本。

This paper introduces the endangerment to pipeline and treatment scheme of frozen soil in Xiangpi Mountain re- gion and Laji Mountain region of Se-Ning-Lan Second Gas Pipeline Project. It analyzes the formation and damage mecha- nism of frozen soil, then obtains the relation between the frost heaving amount and the frost depth of different types of soils. It determines the pipeline damage degree due to frozen soil based on ANSYS model, puts forward the prevention and treatment scheme of frozen soil endangerment to pipeline based on field investigations, i.e. to substitute sand bags for frozen soil to stabilize pipeline. This scheme can solve the effects of frost heaving in winter and thaw settlement in summer on pipeline, also save construction costs.