基于分布式应变监测的埋地管道悬空识别方法研究  

Suspension Identification on Buried Pipeline based on Distributed Strain Monitoring

作　　者：刘绪都 冯新[1] 李明昊 李昕[1] LIU Xudu;FENG Xin;LI Minghao;LI Xin(State Key Lab of Coastal&Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《防灾减灾工程学报》2022年第5期1076-1084,共9页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家重点研发计划项目(2016YFC0802400);国家自然科学基金面上项目(52079024);中央高校基本科研业务费项目(DUT20LAB133)资助。

摘　　要：埋地管道在地基缺陷或管道泄漏作用下会产生局部悬空,悬空的发展不仅会威胁管道的安全运行,还会造成地面沉降、塌陷等地质危害。因此,提出一种基于分布式应变监测的埋地管道悬空识别方法。首先布设分布式应变传感器获取管道沿途任意位置纵向应变,然后提取弯曲应变并判断管道悬空状态的出现,再结合管道弯曲应变建立埋地管道有限元模型,最后通过遗传算法对管道有限元模型的土体刚度进行修正,根据修正后的土体刚度变化定量识别管道悬空出现的位置及范围。通过模型试验验证得出识别结果与试验悬空段两侧坡肩位置最大误差不超过0.2 m,反推出的管道应变峰值和挠度与监测结果相差最大分别为84.1με和3.5 mm,其对应的相对误差分别为7.7%和9.2%,试验误差都控制在工程可以接受的范围以内。研究结果表明:本方法可以实时监测管道的工作应力,反推出管道的挠曲变形,准确判断管道悬空的出现,精确识别出管道悬空的范围。本方法对管道运行的结构状态评估和悬空灾害识别都具有非常积极的意义。Due to foundation defects or pipeline leakage,buried pipelines are prone to be partially suspended. The development of suspended pipelines will not only threaten the safe operation of pipelines,but also cause geological hazards,such as ground subsidence and collapse. Therefore,a suspension identification method of buried pipelines based on distributed strain monitoring is proposed. Firstly,distributed strain sensors are deployed to obtain longitudinal strain distribution along the pipeline,and then the bending strain is calculated and the suspended state of the pipeline is judged. Moreover. a finite element model of the buried pipeline is established based on pipe bending strains,and the soil stiffness of the finite element model is updated using genetic algorithm. Finally,the position and range of pipeline suspension are quantitatively identified according to the modified soil stiffness. The model test results show that the maximum error between the identification result and the positions of the slope shoulder on both sides of the suspended section in the test does not exceed 0.2 m,and the maximum difference between the peak strain and deflection of the pipeline and the monitoring results is 84.1 μεand 3.5 mm,respectively. The corresponding relative errors are 7.7% and 9.2% respectively,which are within the acceptable range of the project. The proposed method can monitor the working stress of the pipeline in real time,deduce the deflection of the pipeline,judge the occurrence of pipeline suspension,and accurately identify the range of pipeline suspension. This method has very positive significance for the evaluation of structure state and the identification of suspension hazards of pipeline operation.

关 键 词：埋地管道 悬空识别 分布式应变 有限元模型修正 遗传算法 

分 类 号：TE832[石油与天然气工程—油气储运工程]