文档介绍：ABSTRACT
This paper is to discuss TBM tunneling in difficult ground conditions, when problems are met which may reduce dramatically the average progress rates and practical consequences may be such as to pose serious questions on the use of mechanized TBM tunnelling versus drill blast and other so-called traditional excavation methods. Following a few remarks on rock TBM tunnelling in relation to the selection and dimensioning of the machine, the attention is posed on the limiting geological conditions which may be envisaged with respect to the use of TBM tunnelling and on the importance of geological and geotechnical investigations, in order to derive an appropriate understanding of the rock mass conditions along the line of the tunnel. The discussion is centered upon the relatively more important or difficult ground conditions including borability limits, instability of excavation walls, instability of excavation face, fault zones and squeezing. Whenever available to the authors and based on project experience, the point of view is illustrated by case examples, which give the opportunity to underline specific difficulties encountered and mendations.
摘要
本篇论文所探讨的内容是:在遇到严重减小掘进速度的不良地质条件下的隧道开挖,并提出采用TBM,钻爆法和其他所谓的传统开挖方法进行隧道掘进时所能遇到的问题。下面是由TBM进行掘进的有关机器选型和尺寸的说明,关注于使用TBM进行掘进的地质条件的限制及地质和地质观测的重要性,所以,要恰当理解隧道沿线的围岩状况。讨论集中于相对重要或不良地质状况的围岩,其中包括可挖性限制,开挖洞壁的不稳定性,开挖掌子面的不稳定性,断层和挤压岩况。利用其他作者之言并基于工程经验,通过实例阐述观点,借此机会强调面临的特殊困难并给出建议。
INTRODUCTION
引言
TBM excavation represent a big investment in an unflexible but potentially very fast method of excavating and supporting a rock tunnel (Barton, 1996). When unfavorable conditions are encountered without warning, time schedule and practical consequences are often far greater in a TBM driven tunnel than in a drill and blast tunnel.
TBM开挖不仅意味着巨额投资,而且可以进行快速开挖和支护(Barton, 1996).在无预警的情况下遇到不良地质条件,从时间和实际产生的结果来讲采用TBM 方法进行隧道掘进远远比采用钻爆法快得多。
The unfavorable conditions can be produced by either a rock mass of very poor quality causing instability of t