摘要
为明确同步注浆充填压力的大小及分布,利用流体力学理论对充填过程进行了理论分析。考虑到盾构推进速度较慢及浆液沿环向充填到最远距离所需的时间很短,假设同步注浆过程中,浆液仅沿环向充填盾尾间隙,即形成三维环形薄饼。分别在浆液为宾汉姆流体和牛顿流体条件下,推导了浆液充填压力沿盾尾间隙环向分布模型;并讨论了该模型的适用范围及主要参数的确定方法。用实际工程监测数据验证了该模型,并分析了浆液充填压力的分布规律及影响因素。分析结果表明:浆液充填压力环向分布模型的计算值与施工现场监测值吻合较好;浆液充填压力沿环向的变化主要由浆液自重的加压或减压作用、浆液剪切应力的减压作用两方面因素引起;浆液充填压力的宾汉姆流体计算值略小于牛顿流体计算值。
To define the magnitude and distribution of filling pressure of synchronous grouting, the theory of fluid mechanics is employed to describe the filling process. Considering that the speed of shield driving is very slow and that the required time of the slurry flowing to the furthest position along the ring is very short, and supposing that the slurry fills the shield tail interspace only along the ring, a three-dimensional circular thin cake is formed. A ring distribution of filling pressure for shield tunnels under synchronous grouting is derived under the Bingham fluid and the Newtonian fluid conditions. The application scope of the model and the calculation method of its main parameters are studied. The validity of the model is certified by use of the monitoring results obtained from certain practical engineering cases, and the distribution laws of filling pressure and the relevant parameters are also analyzed. The results show that the calculated values by the proposed model agree well with the measured ones, that the variation of filling pressure along the ring is caused by the slurry weight and the shear stress, and that the calculated values under the Bingham fluid are slightly less than those under the Newtonian fluid.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2013年第3期590-598,共9页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(51178052
50808020)
关键词
盾构隧道
同步注浆
盾尾间隙
充填压力
shield tunnel
synchronous grouting
shield tail interspace
filling pressure