泥水平衡式盾构模拟试验系统的研制与应用  

Development and application of simulation test system for slurry balance shield

作　　者：齐春[1] 何川[1] 封坤[1] 汤印[1] 王维[1] 夏炜洋[2] QI Chun HE Chuan FENG Kun TANG Yin WANG Wei XIA Wei-yang(MOE Key Laboratory of Transportation Tunnel Engineering, Southwest Jiaotong University, Chengdu 610031, China China Railway Erju Co., Ltd., Chcngdu 610032, China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]中铁二局股份有限公司,四川成都610032

出　　处：《岩土工程学报》2016年第11期1999-2008,共10页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(U1361210;51578462;51208432)

摘　　要：为了探究泥水盾构水下掘进控制和泥水平衡机理等问题,在调研国内外模型盾构设备的基础上确定泥水盾构的基本参数和工作模式,研制出泥水平衡盾构模拟试验系统,包括模型箱、盾构机总成、推进机构、液压动力系统、操作系统、深冷装置等主要部分。该系统可对最高100 m水头条件下泥水平衡盾构施工的主要过程进行模拟,可较真实地再现泥水平衡盾构掘进过程中泥膜的动态形成过程,从而阐明水土压力平衡的机理等关键技术问题,并可为泥水平衡盾构的设计和控制提供重要参数。以砂卵石地层为例配制相似地层和泥浆,并进行盾构试掘进,对设备的功能性进行验证,并初步研究了泥水盾构掘进过程中地表位移的时空变化规律和地层中泥膜的形态。结果表明,由于刀盘无超挖且地层开挖后直接由盾壳支撑,土体移动受到限制,地层变形主要由开挖导致的应力释放产生。排渣装置长度较长,可暂存的渣土量多,使得盾构通过前地表沉降随顶推力和刀盘、排渣装置转速的增大而增大;盾构通过后的地表沉降则由于盾壳与土体的摩擦作用有所减小。在盾构刀盘前方,泥浆渗入地层的范围大致关于盾构轴线对称,泥膜形态呈倒扣的＂锅底＂形分布,其范围约占刀盘外径的20%~43%。To study the excavation control and the balance mechanism on the cutting face during underwater excavation of slurry balance shield（SBS）, the basic parameters and working modes of SBS are determined after investigation of model shield machines worldwide, and then a simulation test system for SBS is developed. The system mainly consists of model box, shield machine assembly, thrusting system, hydraulic power system, operation system and cryogenic unit. It can simulate the main procedure of SBS excavation under the maximum water head of 100 m, and can really reproduce the dynamic formation process of the slurry membrane during excavation, which is critical for illustrating the mechanism of water-earth pressure balance and may provide important parameters for the design and control of SBS. The similar stratum and slurry are prepared based on the sandy gravel strata, and an excavation test is then carried out to verify the function of the simulation system. The space-time variation laws of the ground surface settlements as well as the slurry membrane morphology during shield excavation are also analyzed. The results show that because the cutter head has no over-excavation and the stratum is directly supported by the shield shell, the soil movement is restricted, and the stratum deformation is mainly caused by the stress release caused by the excavation. As the mud discharge device is long, which enhances the temporary storage capacity of mud, the ground surface settlements before shield passing through increase with trust force, cutter head speed and speed of mud discharge device. After the shield passing through, the ground surface settlements decrease due to shield-soil friction. The slurry permeation region in front of the cutter head is approximately symmetric about the shield axis, and the slurry membrane morphology is a flip ＂pot＂ shape, whose dimensions are about 20% to 43% of the external diameter of the cutter head.

关 键 词：隧道工程 泥水平衡盾构 模拟试验系统 地表沉降 泥膜形态 

分 类 号：TU451[建筑科学—岩土工程] U25[建筑科学—土工工程]