跨海区域砾砂地层泥水盾构泥浆成膜效果试验研究  

Experimental study on the film-forming effect of shield mud in gravel formation in cross-sea area

作　　者：李国敏 朱训国[1,2] 夏洪春 李伟[1,2] LI Guomin;ZHU Xunguo;XIA Hongchun;LI Wei(School of Architectural Engineering,Dalian University,Dalian 116622,China;Liaoning Provincial Key Laboratory of Complex Structure Disaster Prediction and Prevention,Dalian 116622,China)

机构地区：[1]大连大学建筑工程学院,辽宁大连116622 [2]辽宁省复杂结构灾害预测与防治重点实验室,辽宁大连116622

出　　处：《辽宁工程技术大学学报（自然科学版）》2024年第2期171-178,共8页Journal of Liaoning Technical University (Natural Science)

基　　金：国家自然科学基金项目(52279116);辽宁省复杂结构灾害预测与防治重点实验室平台重点项目(202101ZD02)。

摘　　要：为揭示泥水盾构开挖面泥浆成膜规律,以青岛地铁8号线泥水盾构掘进的跨海区间为工程背景,阐述不同级配下泥浆的渗透成膜过程,分析高聚物、处理剂作用下3种泥膜形成机理,并结合特定砾砂地层设计成膜装置,采用控制变量法开展室内试验,选用2种粒径细砂调节泥浆级配,分析不同掺量制浆材料(NSHS-3)作用下的泥浆性质。试验结果表明:与粒径小于0.01 mm的细砂相比,粒径小于0.25 mm的细砂形成的渗透带抓抱效果较好且更适配砾砂地层。地层的颗粒级配相同时,泥浆黏度越高,其稳定性越高,泥膜容易形成且厚度较薄、质密、滤水量低,但添加剂过量会引起部分土颗粒聚沉,未加压时便附着在开挖面,进而堵塞盾构管道运输系统,泥膜稳定性较差且造成资源浪费。B6号泥浆加压过程中滤水清澈,滤失量较小,形成的“泥皮+渗透带”型泥膜强度较高,能保证开挖面稳定且絮凝较少,经济性较好。研究结论为类似地层泥水盾构施工改良提供参考。In order to reveal the law of slurry film formation at the excavation face of slurry shield tunneling,based on the engineering background of Qingdao Metro Line 8 mud-water shield tunneling and cross-sea section,the dynamic process of slurry infiltration film-forming with different levels is elaborated,and the formation mechanism of three kinds of mud films under the action of high polymer and treatment agent is analyzed.The film-forming device is designed based on the specific gravel sand stratum.The laboratory test is carried out by using the control variable method,and two kinds of fine sand with particle size are selected to adjust the mud gradation.The mud properties of different NSHS-3 content were analyzed.The test results show that the permeability belt formed by fine sand with particle size less than 0.25 mm has better grasping effect and is more suitable for gravel sand formation than that formed by fine sand with particle size less than 0.01 mm.Under the formation condition of the same particle size distribution,the mud viscosity is higher,the stability is higher,the mud film is easy to form,the thickness is thinner,the quality is dense,and the filter water is low.However,excessive additives can cause some soil particles to gather.When not pressurized,it will adhere to the excavation face,and then block the shield pipeline transportation system.The stability of the mud film is poor and resources are wasted.The test results verify that the filtration water is clear and the filtration loss is small in the process of B6 mud pressurization,and the strength of the mud skin and permeable zone type mud film is high,which ensures the stability of the excavation face and less flocculation,and has better economy.The research conclusions provide a reference for the improvement of slurry shield construction in similar strata.

关 键 词：泥水盾构 砾砂地层 泥浆成膜 渗透机理 泥浆黏度 

分 类 号：TU415[建筑科学—岩土工程]