The design of support for underground excavations

204A

REINFORCEMENT:DIRECT ROCK SUPPORT METHODS

both as an alternative to and as a supplement to the use of mechanical tools for rock cutting. -from Author

more properly referred to as BCC (British Coal Corporation) standards. -from Ailthor

Direct rock support methods ROCK AND SOIL REINFORCEMENT AND SUPPORT 944260 Rock reinforcement technology, testing, design and evaluation C. R. Windsor & A. G. Thompson, in: Comprehensive rock engineering. Vol. 4, ed J.A. Hudson, (Pergamon), 1993, pp 451-484. The chapter defines a limited terminology which should be used in relation to the general discipline of ground rOvement techniques. In particular, support and reinrcement are deemed to be different techniques within this discipline. Further, reinforcing devices are classified into three major categories which are based on their method of load ~ansfer between the particular reinforcing device and the borehole. This enables a better understanding of how each of the many reinforcing devices behaves and aids in the comparison of performance of reinforcing devices within one category or between devices in different categories. A comprehensive table of categories of devices is presented. -from Authors

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Bolts and anchors 944261 Overview of rock anchorages S. Littlejohn, in: Comprehensive rock engineering. Vol. 4, ed J.A. Hudson, (Pergamon), 1993, pp 413-450. Today, anchorages may be employed to solve problems involving direct tension, sliding, overturning, dynamic load and ground prestressing, and the range of applications includes retaining walls, dry docks, concrete dams and spillways, tall buildings, pile testing, bridges, slope stabilization, tunnels, shafts and underground caverns. The purpose of this chapter is to provide guidance on site and ground investigation requirements, design methods, corrosion protection measures, construction techniques and testing procedures for grout-injected rock anchorages. -from Author 944262 Uplift behaviour of plate anchors with geosynthetics N. R. Krishnaswamy & S. P. Parashar, Geotextiles & Geomembranes, 13(2), 1994, pp 67-89. The uplift behaviour of plate anchors embedded in cohesive and cohesiordess soil media, with and without geosynthetics, has been investigated with the help of small-scale model tests in the laboratory. Many factors, such as the type of geosynthetics, the ratio of the area of the geosynthetic inclusion to the area of the plate anchor, the depth of embedment, the type of soil, the strain rate and the position of the water table, have been found to signilicantly influence the uplift behaviour of plate anchors. -from Authors 944263 The development of rock bolting in UK coal mines P. Williams, Mining Engineer, 153(392), 1994, pp 307-312. The paper considers the statutory and policy background o f ~ e develop of rock bolting in British coal mines from lg>O to 1980. It outlines the perceived problems for safe ana erucient coal production in the 1980s and the contribution anticipated from rock bolting. The stages by which the current technology of rock bolting developed are described. The paper concludes that rock bolting and its supporting technology have reached the stage where the removal of statutory constraints can be favourably considered; subject to technical standards which may now be

944264 The design of s u p p o r t for u n d e r g r o u n d excavations P. Choquet & J. Hadjigeorgiou, in: Comprehensive rock engineering. Vol. 4, ed J.A. Hudson, (Pergamon), 1993, pp 313-348. This chapter deals with the design of underground s u ~ r t systems for both civil and mining applications. It is apparent that the fulfillment of the main timk, i.e. the successful design of a support system, can be accomplished by rational, empirical and observational methods. The presented techniques are but tools in this d e s ~ process. Rather than argue the superiority of one method over another, it is felt that most technkjues can be employed in a complementary fashion with thetr applicability influenced by the prevalent conditions, state of knowledge and presence of qualified personnel. The ultimate goal m the design of a safe and economical support system for the life of the project. -from Authors 944265 Development of tunnel support philosophy A. M . M . Wood, in: Comprehensive rock eitgtneertng. Vol. 4, ed J.A. Hudson, (Pergamon), 1993, pp 349-368. The main purpose of this chapter is to review recent developments m support strategy from the v i e ~ i n t of a practising engineer, to illustrate elements of the choice for any tunnel and the reasons for preference of a particular approach, advocating the maintenance at all times of an eclectic attitude. There is no universally applicable optimal method but there are some common princi-p]es. -from Author 944266 Rock mass response to large blast hole open stoping B . L . Stillborg, in: Comprehensive rock engineering. VoL 4, ed J.A. Hudson, (Pergamon), 1993, pp 485-511. Presents a case study of the rock engineering investigation based on the activities of the Swedish ~ g Research Foundation at the Luossavaara mine. The work, aimed at introducing new technology to the Swedish mining industry had three major components: a geomechanics preinvestigation focusing on methods applicable to mining; rock reinforcement studies for prereinforcement; and an instrumentation and monitoring scheme for observation during mining activities. The chapter details the work with emphasis on mine layout design, including pillar design, design and support of loading level, hanging wall s ~ , and footwall support. The chapter concludes with a series of conclusions derived from the work. -R.Gower 944267 An overview of application of coal mine g r o u n d control techniques in the USA S . S . Peng, in: Comprehensive rock engineering. Vol. 5, ed J.A. Hudson, (Pergamon), 1993, pp 433'450. In this chapter two case studies are described t o illustrate the complicated nature of coal mine ground control. The first involves a longwaU mine and the design of shield supports and is described in terms of underground m o n i t o ~ g tor optimum choice of shield design. In this study a successful assessment resulted in increased productivity in the relevant panel. The second case study examines cutter roof problems where excavation of a coal seam is carried out from within the seam and roof bolting can fail and col, lapse. Underground observation work is detailed and a pillar support technique, and a roof support system are examined. -R,Gower 944268 Feissicherungsarbeiten an d e r Burgruine Dra. chenfels (Sudlffalz) (Rock protection works at the Drachenfels castle ruin, S u d p f i l z ) F. Harrier & U. Schroeder, Mainzer Geowissenschaftliche Mitteilungen, 22, 1993, pp 145-158. A large boulder threatened to fall down from the upper part of the Drachenfels (SudpfaLz) with its famous castle ruin. Accompanied by permanent control of the rock movement by distance measuring, the first step was to use temporary