- Email: [email protected]
Rock slope engineering
Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. Vol. 15, p. 39. Pergamon Press 1978. Printed in Great Britain
Book Reviews Rock Slope Engineering--by E. H o e k & J. W. Bray. Revised 2nd Edn. Institute of Mining & Metallurgy, London, 1977. 402 pp., £10 (U.S. $19). The revised second edition of this pioneering book, appearing only three years after the first, must indicate its popularity--and usefulness. It continues as the leading work in this field. The original edition of 309 pages, was largely the result of outstanding, practical research into rock slopes logically developed by a team at the Royal School of Mines, London, led by the authors, in the late 1960s and early 1970s. The stated aim of the book was to describe the 'tools and techniques' required to collect the blend of ingredients necessary for the design of a particular slope, from basic geological data, rock strength characteristics, groundwater observations and 'a good measure of engineering common sense'. To do this the first edition had ten chapters starting with economic and planning considerations and basic mechanics of slope failure. It progressed with the aid of a limited number of case histories-largely from open cast mining experience, to extensive chapters on collection and presentation of geological data, rock strength and groundwater and then onto geometrical forms of rock failure--plain, wedge and circular. It ended with a brief chapter of miscellaneous topics which included local remedial measures (drainage, surface protection of slopes, control of rock falls and monitoring), and appendices on wedge-failure analysis and mathematical tables. In the second edition, the useful wide margins and the small margin sketches remain and improvements have been made to the typescript of the offset lithography. The chapters on basic mechanisms, collection and presentation of geology data and rock strength have been revised and chapters added on wedge failure, and particularly welcome, on blasting. Enough to recommend strongly first edition owners to read the added material but perhaps not enough to make them consider a new purchase. However, at £10 (U.S. $19) a remark-
ably good value buy for potential new owners, firms and libraries and essential reading for all concerned with any form of rock slope stability. A criticism of the first edition was that perhaps a more appropriate title would have been "Rock Slope Analysis". This remains valid; the construction engineering content is still quite small and miscellaneous topics, the last chapter, where rock stabilisation by means other than , by adjustments to slope geometry is discussed, is probably the weakest chapter. For example, the recent major advances in rock bolts and anchors by Littlejohn and others, or advances in stabilisation by grouting are hardly mentioned. These omissions must be deliberate, which seems a pity with the book having the title it does and following on from sparkling and carefully argued chapters on observational and analytical work leading the reader on to discussion of actual failure modes and the geometry of the cuts required to keep them stable. An important point, more of a comment on the state of the art than a criticism of the book, is that at the end of a rock slope analysis, when the engineer (or geologist) may have slowly, even painfully, trod through the maze of numerical paths, he probably cannot be confident that his factor of safety on paper adequately describes the stability of his slope. In many situations the part played by cohesion (or its equivalent in rocks) is almost certainly a more elusive parameter in rock work than in soils. A practical way to help this problem and where the book is thin in its coverage, is for many more analysed and published case histories. Another problem is that many of the analytical techniques, for example, a single extensive fault plotted on a polar diagram, do not assign a batting order to the most likely modes of failure. As the authors take pains to point out, the engineer's judgement still plays the major part in competent rock slope design. P.G.F.
Mechanics of Thrust Faults and Decollement--edited by B. Voight.
opment of this approach through papers such as Terzaghi's "Stress conditions for the failure of saturated concrete and rock" (1945) and his "Mechanism of landslides" (1950), Skempton's "Terzaghi's discovery of effective stress" (1960), Hubert and Rubey's "Role of fluid pressure in mechanics of overthrust faulting" (1959), and the number of papers such as those by Raleigh and Griggs (1963) and Hsu (1969) derived from Hubbert and Rubey's contribution. In the field of rock deformation, it is equally instructive to be able to consider collectively the classic papers of Daubr6e (1879), Adams and Nicholson (1898) and yon Karman (1911). As well as providing ready access to the major contributions to the discussion of a fascinating geological problem, this volume also provides an intriguing study in the philosophy of the development of scientific knowledge. It is not often that readers of the geological or geotechnical literature are invited to consider whether or not a certain advance in their subject has resulted from the traditional evolutionary processes of "normal science" or whether it is a Kuhnian paradigm representing an unprecedented or revolutionary scientific achievement. Whether or not Terzaghi's discovery of the law of effective stress fully meets Kuhn's requirements for acceptance as a paradigm is a question unlikely to find easy resolution; that its impact on understanding of the mechanics of materials in the Earth's crust has been truly revolutionary is unquestionable. In highlighting this achievement, Professor Voight has produced a volume that could well find a place next to From Theory to Practice in Soil Mechanics among this reviewer's favourite books.
Dowden, Hutchinson & Ross, Stroudsberg, Penn. (distributed by John Wiley & Sons Ltd.), 1977. 471 pp., £24.00 (U.S. $40.65). This book is Volume 32 in the publisher's Benchmark Papers in Geology series. Each volume in this series collects together the classic or key papers published on a given geological topic, and reproduces them either in full or in part, together with a linking commentary prepared by the volume editor. The subject of the present volume, so skillfully assembled by Professor Barry Voight, will surely be of great interest to both geologists and geotechnical engineers. The apparent mechanical paradox involved in overthrust faulting and the mechanics of the complex folding often involved in mountain building, have long held the fascination of geologists. The principles and experimental research used to develop solutions to these problems should be of major interest to rock mechanics engineers even if the basic geological questions involved are not. The approach used in this volume, as in the series, is an historical one. It traces the development of understanding of the mechanics of thrust faults and decollement by presenting, in approximately chronological order, the classic papers in the field dating back to 1815. The Editor's perceptive and scholarly comments provide an invaluable link between the groups of papers presented, and serve as an aid to the reader's appreciation of the development of this small aspect of geological knowledge. The essential key to the mechanics of thrust faulting is, of course, Terzaghi's principle of effective stress, as applied by Hubbert and Rubey in their classic paper of 1959. It is both exciting and instructive to be able to study the devel-
E.T.B.
39
Book Reviews Rock Slope Engineering--by E. H o e k & J. W. Bray. Revised 2nd Edn. Institute of Mining & Metallurgy, London, 1977. 402 pp., £10 (U.S. $19). The revised second edition of this pioneering book, appearing only three years after the first, must indicate its popularity--and usefulness. It continues as the leading work in this field. The original edition of 309 pages, was largely the result of outstanding, practical research into rock slopes logically developed by a team at the Royal School of Mines, London, led by the authors, in the late 1960s and early 1970s. The stated aim of the book was to describe the 'tools and techniques' required to collect the blend of ingredients necessary for the design of a particular slope, from basic geological data, rock strength characteristics, groundwater observations and 'a good measure of engineering common sense'. To do this the first edition had ten chapters starting with economic and planning considerations and basic mechanics of slope failure. It progressed with the aid of a limited number of case histories-largely from open cast mining experience, to extensive chapters on collection and presentation of geological data, rock strength and groundwater and then onto geometrical forms of rock failure--plain, wedge and circular. It ended with a brief chapter of miscellaneous topics which included local remedial measures (drainage, surface protection of slopes, control of rock falls and monitoring), and appendices on wedge-failure analysis and mathematical tables. In the second edition, the useful wide margins and the small margin sketches remain and improvements have been made to the typescript of the offset lithography. The chapters on basic mechanisms, collection and presentation of geology data and rock strength have been revised and chapters added on wedge failure, and particularly welcome, on blasting. Enough to recommend strongly first edition owners to read the added material but perhaps not enough to make them consider a new purchase. However, at £10 (U.S. $19) a remark-
ably good value buy for potential new owners, firms and libraries and essential reading for all concerned with any form of rock slope stability. A criticism of the first edition was that perhaps a more appropriate title would have been "Rock Slope Analysis". This remains valid; the construction engineering content is still quite small and miscellaneous topics, the last chapter, where rock stabilisation by means other than , by adjustments to slope geometry is discussed, is probably the weakest chapter. For example, the recent major advances in rock bolts and anchors by Littlejohn and others, or advances in stabilisation by grouting are hardly mentioned. These omissions must be deliberate, which seems a pity with the book having the title it does and following on from sparkling and carefully argued chapters on observational and analytical work leading the reader on to discussion of actual failure modes and the geometry of the cuts required to keep them stable. An important point, more of a comment on the state of the art than a criticism of the book, is that at the end of a rock slope analysis, when the engineer (or geologist) may have slowly, even painfully, trod through the maze of numerical paths, he probably cannot be confident that his factor of safety on paper adequately describes the stability of his slope. In many situations the part played by cohesion (or its equivalent in rocks) is almost certainly a more elusive parameter in rock work than in soils. A practical way to help this problem and where the book is thin in its coverage, is for many more analysed and published case histories. Another problem is that many of the analytical techniques, for example, a single extensive fault plotted on a polar diagram, do not assign a batting order to the most likely modes of failure. As the authors take pains to point out, the engineer's judgement still plays the major part in competent rock slope design. P.G.F.
Mechanics of Thrust Faults and Decollement--edited by B. Voight.
opment of this approach through papers such as Terzaghi's "Stress conditions for the failure of saturated concrete and rock" (1945) and his "Mechanism of landslides" (1950), Skempton's "Terzaghi's discovery of effective stress" (1960), Hubert and Rubey's "Role of fluid pressure in mechanics of overthrust faulting" (1959), and the number of papers such as those by Raleigh and Griggs (1963) and Hsu (1969) derived from Hubbert and Rubey's contribution. In the field of rock deformation, it is equally instructive to be able to consider collectively the classic papers of Daubr6e (1879), Adams and Nicholson (1898) and yon Karman (1911). As well as providing ready access to the major contributions to the discussion of a fascinating geological problem, this volume also provides an intriguing study in the philosophy of the development of scientific knowledge. It is not often that readers of the geological or geotechnical literature are invited to consider whether or not a certain advance in their subject has resulted from the traditional evolutionary processes of "normal science" or whether it is a Kuhnian paradigm representing an unprecedented or revolutionary scientific achievement. Whether or not Terzaghi's discovery of the law of effective stress fully meets Kuhn's requirements for acceptance as a paradigm is a question unlikely to find easy resolution; that its impact on understanding of the mechanics of materials in the Earth's crust has been truly revolutionary is unquestionable. In highlighting this achievement, Professor Voight has produced a volume that could well find a place next to From Theory to Practice in Soil Mechanics among this reviewer's favourite books.
Dowden, Hutchinson & Ross, Stroudsberg, Penn. (distributed by John Wiley & Sons Ltd.), 1977. 471 pp., £24.00 (U.S. $40.65). This book is Volume 32 in the publisher's Benchmark Papers in Geology series. Each volume in this series collects together the classic or key papers published on a given geological topic, and reproduces them either in full or in part, together with a linking commentary prepared by the volume editor. The subject of the present volume, so skillfully assembled by Professor Barry Voight, will surely be of great interest to both geologists and geotechnical engineers. The apparent mechanical paradox involved in overthrust faulting and the mechanics of the complex folding often involved in mountain building, have long held the fascination of geologists. The principles and experimental research used to develop solutions to these problems should be of major interest to rock mechanics engineers even if the basic geological questions involved are not. The approach used in this volume, as in the series, is an historical one. It traces the development of understanding of the mechanics of thrust faults and decollement by presenting, in approximately chronological order, the classic papers in the field dating back to 1815. The Editor's perceptive and scholarly comments provide an invaluable link between the groups of papers presented, and serve as an aid to the reader's appreciation of the development of this small aspect of geological knowledge. The essential key to the mechanics of thrust faulting is, of course, Terzaghi's principle of effective stress, as applied by Hubbert and Rubey in their classic paper of 1959. It is both exciting and instructive to be able to study the devel-
E.T.B.
39