海水与高温环境对膨润土泥浆流变特性的影响研究  

Study on the Effects of Seawater and High Temperature Environment on the Rheological Properties of Bentonite Slurry

作　　者：周骥 王希浩 康松 代镇洋 ZHOU Ji;WANG Xihao;KANG Song;DAI Zhenyang(CCCC Tunnel Engineering Co.,Ltd.,Beijing 100088;Qingdao Guoxin Second Jiaozhou Bay Undersea Tunnel Co.,Ltd.,Qingdao 266000)

机构地区：[1]中交隧道工程局有限公司,北京100088 [2]青岛国信胶州湾第二海底隧道有限公司,青岛266000

出　　处：《现代隧道技术》2024年第1期174-181,199,共9页Modern Tunnelling Technology

基　　金：青岛国信胶州湾第二海底隧道有限公司2023年度重大科研创新揭榜挂帅项目.

摘　　要：泥水盾构在海底掘进时,配制合适的泥浆以确保其在海水入侵和高温条件下良好的流变性能和渗透特性具有重要意义。为探明高温环境与海水侵入对膨润土浆液流变性能的影响,利用博勒飞RST软固体流变仪开展一系列流变测试试验,分析高温环境与海水侵入条件下泥浆的流动形式与本构模型。结果表明:在高温环境下,膨润土泥浆具有明显的升温稀化特性,随着温度的升高,膨润土泥浆的流变模型未发生变化;随着海水的侵入,泥浆的保水能力和物理稳定性被削弱,并出现离析现象,膨润土泥浆近乎丧失了幂律流体与屈服性流体的流变特征,泥浆的流动形式劣化为牛顿流体;此外,电镜扫描结果显示淡水泥浆的空间结构呈结块团絮状,结块密集且相互连续,空间结构较为完整且致密;50%海水泥浆的空间结构主要以薄片形式出现,且薄片之间存在明显的空隙,局部出现离散颗粒堆积。For tunnelling in seabed by a slurry shield,it is of great importance to prepare a suitable slurry that en⁃sures desirable rheological properties and permeability characteristics in an environment with seawater intrusion and high temperature.In order to ascertain the effects of high temperature and seawater intrusion on the rheological property of bentonite slurry,a set of rheological tests have been conducted by using the Brookfield RST Soft Solids Tester Rheometer,and the flow pattern and constitutive model of slurry in an environment with high temperature and seawater intrusion have been analyzed.As the results indicate:In high temperature environment,bentonite slurry clearly experiences thinning induced by temperature rise.As the temperature increases,the rheological model of bentonite slurry does not change.With seawater intrusion,the water retention capacity and physical stability are di⁃minished and it experiences segregation.The bentonite slurry virtually loses the rheological characteristics of powerlaw fluid and yield fluid,and the flow pattern of slurry is degraded to that of Newtonian fluid.Besides,the results of electron microscope scanning indicate that the space structure of fresh water slurry appears as lumpy flocculent shape,there are dense and contiguous lumps,and the space structure is complete and dense.In 50%of the seawater slurry,space structure appears as flaky form,there is noticeable gap between the flakes,and local areas have accu⁃mulation of discrete particles.

关 键 词：海底隧道 泥水盾构 海水侵入 高温环境 流变特性 室内试验 

分 类 号：U455[建筑科学—桥梁与隧道工程]