270 Pages 138 B/W Illustrations
    by CRC Press

    270 Pages 138 B/W Illustrations
    by CRC Press

    Rock falls can be a public safety issue. This book provides comprehensive information on identification of these hazards, and design and construction of protection methods.

    Rock Fall Engineering describes first, the theoretical background to rock fall behavior in terms of the impact and trajectory phases of rock falls, and second, how this information is applied to modeling of rock falls and the design of ditches, fences and sheds. The theory of rock fall behavior is verified by comparing the calculations with five carefully documented case studies.

    The book covers four main topics as follows:

    • Describes causes of rock falls, including geology, climate and topography, and provides detailed documentation on rock fall impacts and trajectories at five sites with a wide variety of topographic and geologic features
    • Discusses theory of impact mechanics, and its application to velocity and energy changes during impacts and trajectories
    • Reviews methods of modeling rock fall events, and presents analyses for the five case studies
    • Examines rock fall protection in terms of selecting appropriate method(s) for site conditions, and design principles in which the objective is to absorb impact energy in an efficient manner

    This book, which contains many worked examples, is of interest to practitioners and researchers working in the fields of geological engineering and natural hazards.

    Duncan C. Wyllie is a principal with Wyllie & Norrish Rock Engineers in Vancouver, Canada, and a registered professional engineer in British Columbia. He has worked on rock fall hazard projects involving the design and construction protection measures since the 1970s. He is the author of Foundations on Rock, Second Edition, and Rock Slope Engineering, Fourth Edition, both published by CRC Press.

    Rock Falls – Causes And Consequences

    Source Zones And Topography


    Weather Effects On Rock Falls

    Vegetation Effects On Rock Falls

    Seismic Effects On Rock Falls

    Human And Animal Influences On Rock Falls

    Consequences Of Rock Falls

    Documentation Of Rock Fall Events

    Impacts On Rock Slopes

    Impacts On Talus And Colluvium Slopes

    Impacts On Asphalt

    Impact With Concrete

    Summary Of Case Study Results

    Rock Fall Velocities And Trajectories

    Trajectory Calculations

    Rock Fall Velocities

    Variation Of Trajectories With Restitution Angle

    Angular Velocity

    Field Observations Of Rock Fall Trajectories

    Impact Mechanics

    Principles Of Rigid Body Impact

    Forces And Impulses Generated During Collinear Impact

    Energy Changes During Impact

    Coefficient Of Restitution

    Friction And Angular Velocity Changes During Impact

    Impact Behaviour For Rough, Rotating Body

    Calculated Vs Actual Restitution Velocities

    Coefficient Of Restitution

    Newton’s Coefficient Of Restitution

    Normal Coefficient Of Restitution

    Tangential Coefficient Of Restitution And Friction

    Energy Changes During Impacts And Trajectories

    Impact Mechanics Theory And Kinetic Energy Changes

    Rotational Energy Gains/Losses

    Total Energy Losses

    Energy Loss Diagrams

    Loss Of Mass During Impact

    Effect Of Trees On Energy Losses

    Rock Fall Modelling

    Spreadsheet Calculations

    Terrain Model – Two Dimensional V Three Dimensional Analysis

    Modelling Methods – Lumped Mass

    Modelling Methods – Discrete Element Model (DEM)

    Modelling Results Of Case Studies

    Summary Of Rock Fall Simulation Results

    Selection Of Protection Structures

    Impact Energy – Deterministic And Probabilistic Design Values

    Impact Energy – Service And Ultimate States Energies

    Impact Energy – Probability Calculations

    Determination Of Rock Fall Return Periods

    Risk Management Of Rock Fall Hazards

    Design Principles Of Rock Fall Protection Structures

    Structure Location With Respect To Impact Points

    Attenuation Of Rock Fall Energy In Protection Structures

    Minimizing Forces In Rock Fall Protection Fences

    Design Of Stiff, Attenuator Fences

    Model Testing Of Protection Structures

    Rock Fall Protection I – Barriers, Nets And Fences

    Ditches And Barriers

    MSE Embankments

    Slide Detector Fences

    Wire Mesh – Draped and Pinned

    Nets and fences

    Rock Fall Protection II - Rock Sheds

    Types of rock sheds

    Reinforced concrete sheds

    Cantilevered structures

    Sheds with sloping roofs

    Wire mesh canopies



    Duncan C. Wyllie has a physics degree from the University of London and engineering degrees from the University the New South Wales, Australia and the University of California, Berkeley. He is a principal with Wyllie & Norrish Rock Engineers in Vancouver, Canada, and a registered professional engineer in British Columbia. Duncan Wyllie has lectured widely and has also authored or co-authored a number of textbooks on applied rock mechanics including Foundations on Rock (1st and 2nd editions in 1989 and 2001), and Rock Slope Engineering, Fourth Edition (2002), both published by Taylor & Francis.

    "This book provides an invaluable perspective to engineers and geologists dealing with rock slope failures: not so much what causes the failures in the first instance, but what happens to the rock masses as they move, and therefore how to analyse them. I don’t think that there is a good, systematic, treatment elsewhere."
    ––Eddie Bromhead, retired from Kingston University, London, UK

    "… a comprehensive book containing both the theory and practice of rock fall engineering. The author is experienced not only in these subjects but also in compiling books that present the material in a particularly easy-to-understand manner—which will be appreciated by all readers whether they be engineers, contractors, clients, researchers, teachers or students. In short, this book contains the necessary information to understand and design rock fall protection."
    —Emeritus Professor John A. Hudson, Imperial College London