Bench stability in open pit mines : a methodology for jointed rock masses
The methods used to determine the overall gradients of the slopes in open pit workings aim to sufficiently eliminate all risk of failure on a scale comparable wich the pit walls. For this the slopes musc be made shallow gradual and reinforcing measures must generally be applied. Most often these consist of ensuring the drainage of the slopes and in limiting the effects of blasting (reinforcement is generally too costly in the case of very high slopes and deep planes of failure).
Risk and risk analysis in rock engineering
Abstract Risk analysis and decision-making procedures are being applied to large engineering projects with increasing frequency. Risk analysis is a versatile tool in decision-making, whether the decisions are in the form of an engineering design, selecting particular construction procedures, or more general decisions made by private or public entities. An overview of the basic aspects of risk analysis and decision-making are followed by a detailed discussion of three typical rock engineering applications: (1) slope design, (2) flow through fractured media, and (3) tunnelling. The paper includes examples from current tunnel projects (e.g., the Gotthard base tunnel, the Adler tunnel and the Lotschberg base tunnel).
A STATISTICALLY BASED NUMERICAL MODEL FOR HEAT CONDUCTION IN FRACTURED ROCK MASSES
A computational procedure for simulating heat conduction in fractured rock masses is proposed and illustrated within the context of the finite element method. The procedure makes use of simple local models for conduction in the vicinity of a single open fracture. The local models allow effective thermal properties for fractured rock to be expressed in terms of fracture characteristics such as spacing, orientation and aperture. The distributions of fractures and fracture properties within the finite element model are derived from a statistical representation of geological field data. The procedure is demonstrated to satisfactorily reproduce heat transfer results across single fractures and provide an efficient means of representing conduction in formations with multiple fractures. (Author/TRRL)