漠大线多年冻土沼泽区管道融沉防治及温度监测

漠大线管道自投产以来,全年均为正温输送,且输送温度远高于设计预期温度,因而加速了管道周围冻土区的融化,管道容易发生融沉,安全性面临极大考验。结合漠大线投产后的实际运行情况,参考冻土区工程建设经验,设计了热棒与粗颗粒土换填相结合的多年冻土沼泽区域管道融沉防治方案,并在漠大线K305处完成了100 m示范段建设,并在示范段管道周围土壤中安装了温度监测系统,通过近一年的温度监测数据分析了目前示范段的融沉防治情况。结果表明：热棒的安装降低了管道地基的温度,增加了土壤的冷储量,起到了稳定地基的作用,而管道底部换填的粗颗粒土可以保障热棒的制冷作用不会引发管道冻胀灾害。

Thaw settlement prevention and temperature monitor of Mohe-Daqing Crude Oil Pipeline in permafrost marsh zone

Since put into operation, Mohe-Daqing Crude Oil Pipeline has been running at positive temperature all year round, with transpot temperature much higher than the design temperature, as a result, melting of the soil around the pipeline has been sped up, making the pipeline prone to thaw settlement, posing great challenges to the pipeline security. In view of the actual operation conditions of Mohe-Daqing Crude Oil Pipeline, and engineering construction experience in permafrost zones, a scheme preventing thaw settlement combining thermal probes with coarse-grained soil filling is proposed. A 100 m long demonstration section has been constructed in K305 of Mohe-Daqing Crude Oil Pipeline, and temperature monitoring system has been installed in the surrounding soil of the demonstration section. The condition of thaw settlement prevention at the demonstration section has been analyzed by using monitored temperatures in nearly a year. The results show that installment of thermal probes has reduced the temperature of pipeline foundation, increased the cold storage of the soil, making the foundation more stable, and the coarse-gained soil filled at the bottom of pipeline can ensure the pipeline from frost heaving by thermal probes＇ refrigeration.