摘要
分析基坑工程对邻近天然气管道的有害因素、天然气管道保护措施。结合工程案例,探讨基坑工程保护天然气管道的措施。给出基坑周边地下管线的监测报警值。采用基坑支护结构专用软件进行基坑周围地表沉降计算,得到土体最大沉降量为53.9 mm,不满足规范对于周边柔性管线的要求。提出2种保护措施:加强基坑围护强度、土体加固。采用大型岩土有限元分析软件Midas/GTS进行模型计算,分析基坑开挖对天然气管道的影响及袖阀管注浆加固土体后对天然气管道的影响。燃气管道最大变形位移为41.38 mm,超出规范对于周边柔性管线的变形位移要求。经过土体加固后,管道的变形位移大幅下降,满足规范对于周边柔性管线的要求。工程设计方案经过技术经济比较后,采取了加强基坑围护强度结合施工过程中进行管道监测的措施,土体加固方案作为管道变形位移超过监测预警值的应急方案。基坑施工过程中对省天然气管道进行监测,可知采取的保护措施有效且可靠,基坑施工期间天然气管道运行状态安全可控。文末附有基坑工程演示视频,可扫二维码观看。
The harmful factors of the foundation pit engineering to the adjacent natural gas pipeline and the protection measures of the natural gas pipeline are analyzed.Combined with engineering cases,the measures to protect natural gas pipelines in foundation pit engineering are discussed.The monitoring alarm value of the underground pipeline around the foundation pit is given.The special software for foundation pit supporting structure was used to calculate the ground settlement around the foundation pit,the maximum settlement of the soil was 53.9 mm,which did not meet the requirements of the code for the surrounding flexible pipelines.Two kinds of protection measures are proposed:strengthening the foundation pit enclosure strength and soil reinforcement.The large-scale geotechnical finite element analysis software Midas/GTS was used for model calculation to analyze the influence of foundation pit excavation on the natural gas pipeline and the influence of the reinforcement of the soil by sleeve valve tube grouting on the natural gas pipeline.The maximum deformation displacement of the gas pipeline was 41.38 mm,which exceeded the requirements of the code for the deformation displacement of the surrounding flexible pipeline.After the reinforcement of the soil,the deformation displacement of the pipeline decreased significantly,meeting the requirements for the surrounding flexible pipelines.After the technical and economic comparison of the engineering design scheme,the measures to strengthen the foundation pit enclosure strength combined with pipeline monitoring during the construction process were taken.The soil reinforcement scheme was used as an emergency scheme for pipeline deformation displacement exceeding the monitoring and early warning value.The provincial natural gas pipeline was monitored during the construction of the foundation pit,which shows that the protective measures taken are effective and reliable,and the operation state of the natural gas pipeline is safe and controllable during the construction of the foundation pit.At the end of the paper,the demonstration video of the foundation pit engineering is included,which can be watched by scanning the QR code.
作者
朱琴君
庞志辉
何伟
翟天平
李超
ZHU Qinjun;PANG Zhihui;HE Wei;ZHAI Tianping;LI Chao
出处
《煤气与热力》
2020年第6期38-42,J0044,共6页
Gas & Heat
关键词
基坑工程
天然气管道
基坑围护
土体加固
foundation pit engineering
natural gas pipeline
foundation pit enclosure
soil reinforcement
