摘要
近年来,泥水盾构工法在越江跨海隧道中被广泛应用,在泥水盾构施工过程中,带压开舱始终是一个高风险、高难度技术环节。盾构带压开舱能否成功的关键在于泥膜的闭气性能。然而,一直以来泥膜闭气破坏机制、闭气时间及其影响因素从理论上较少探讨。对此,首先考虑了气体对泥膜中孔隙水的驱替作用,建立了泥膜压气从渗流启动-击穿渗透带的多相流模型,提出了泥膜压气渗水量和闭气时间评估方法;然后开展了室内渗透柱泥膜压气破坏试验,验证了所提出理论方法的适用性;最后探讨了气压、地层参数、泥膜厚度、泥浆剪切强度等参数对闭气时间的影响规律,揭示了盾构带压开舱以“泥皮为主、渗透带为辅”的闭气作用。研究成果对泥水盾构带压开舱的安全保障有一定的借鉴意义。
In recent years,the slurry shield method has been extensively used for tunneling under seas or rivers.In the process of slurry shield construction,opening the chamber under air pressure has always been a high-risk and difficult task.The key to the success of opening the chamber under air pressure lies in the filter cake airtightness property.However,there has been less theoretical research on the mechanism of failure of filter cake airtightness property,airproof time and its influencing factors.Therefore,considering the effects of air pressure and pore water,we establish a transient mechanical model "percolation initiation–failure under air pressure" of filter cake based on multiphase flow theory,and propose a method for predicting water discharge mass through filter cake and airproof time under air pressure.Then,we conduct the laboratory filter cake airproof test to verify the applicability of the proposed theoretical approach.Finally,the influences of air pressure,stratigraphic parameters,filter cake thickness,slurry shear strength and other parameters on filter cake airproof time are discussed,and the results reveal that the airproof effect mainly depends on the filter cake under air pressure,followed by infiltration zone.This study can provide some reference for the safety of opening chamber under air pressure in slurry shield.
作者
蔡博文
金大龙
李兴高
袁大军
陈健
杨公标
CAI Bo-wen;JIN Da-long;LI Xing-gao;YUAN Da-jun;CHEN Jian;YANG Gong-biao(Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;China Railway 14th Bureau Group Corporation Limited,Jinan,Shandong 250101,China;China Railway Construction Underwater Tunnel Engineering Laboratory,Jinan,Shandong 250220,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2023年第5期1395-1404,1415,共11页
Rock and Soil Mechanics
基金
国家自然科学基金青年基金资助项目(No.52008021)
北京市科技新星计划项目(No.20220484037)
高速铁路基础研究联合基金资助项目(No.U1834208)。
关键词
泥水盾构
带压开舱
泥膜
闭气时间
闭气性能
slurry shield
opening chamber under air pressure
filter cake
airproof time
airtightness property
