Book review

Reflections on Slope Stability Engineering by Edward N. Bromhead, 2024. CRC Press, Taylor & Francis Group, Abingdon, 198 pp. ISBN 9781032548951, paperback, £45.99. ISBN 9781032549316, hardback, £105.00. ISBN 9781003428169, eBook, £41.39.

I will start by getting the obvious out of the way: this is not a textbook. It is exactly as the title states, a series of reflections on a long career spent in slope stability engineering. There are no diagrams, pictures or equations and the author suggests that it might be best read in the eBook format. Like him I am a great fan of eBooks but the location of some often-interesting, as well as essential, notes at the end of each chapter meant that I was pleased to be reading the paperback version.

Chapter 1 on ‘Landslide recognition, description, classification and mapping’ is perhaps the most reflective of the chapters. Some of the anecdotes will undoubtedly amuse, not least the tale of the occupants of a gazebo who caused a seismically induced landslide and the saga of ‘turfy soil’ in which the author and I have been involved for some years. He and I also share some frustration with the differences between UK ‘(International!)’ English and American English.

The chapters that follow deal with the following: 2, Ground investigations; 3, Causes; 4, Ideas in analysis; 5, Modern methods and back analysis; 6, Water, mainly in the ground; 7, Surface water; 8, Landslides without stabilization; 9, Remedying landslides (some of the titles are shortened here in the interests of brevity).

These chapters are much more technical, and the author essentially states his personal views and preferences for one method, tool or technique over another and backs these up with reasons, examples and detailed descriptions. The descriptions, remembering that there are no diagrams or equations, only words, are very clear indeed. I found the descriptions of the main types of piezometers, for example, to be much clearer than any set of diagrams that I have seen.

I mentioned the notes at the end of each chapter above and these range from pointing the reader to key references on a particular subject, through related anecdotes, to additional advice and guidance (reflections) that would not fit naturally within the text. Just occasionally these are a little unrestrained, as with the comment about the treatment of the ring shear test in BS1377, although that is not to say that they are incorrect.

In a series of reflections such as this it seems almost inevitable that the reader's own ‘counter-reflections’ will diverge from those of the author in some instances. One example of this is the author's view of landslide distribution in the UK mirroring the outcrops of clay soils and additionally following the coast. This seems to rather miss the common occurrence of flow-type events that occur in Scotland, northern England and Wales. That said, the author's statement broadly works for slides, notwithstanding that there are deep-seated landslides in the north and west, including some truly spectacular examples on the Isle of Skye.

The statement that the ‘probability of vehicles being hit by falling rocks is less than that of vehicles driving into a rock’ is correct. However, for fatality risk, in the notionally similar case for debris flow the situation is reversed simply because of the opportunity for drivers to brake and decrease the impact speed (Winter and Wong 2020).

Minor divergences and clarifications aside, the discourse on data formats and removable drives rings only too true. I well remember my disappointment and even horror on realizing that not only a large collection of 250 Mb Zip discs could not be read but also that I could not even connect the drive to my new computer. I also share the author's frustration with the presence on our road network of rockfall warnings signs that face the ‘wrong’ way; not least as the Traffic Signs Manual (Chapter 4, Warning Signs, Anon. 2018) requires that ‘The appropriate variant is used to indicate which side rocks might fall’.

I perhaps gained most from the author's insights into analysis and the effects of water on stability (Chapters 4, 5 and 6) but I am sure that the value for each reader will be different depending on their experience and interest.

The book ends with the author's ‘Epilogue’ in which, in his own words, he offers ‘a compendium of things left unsaid … or perhaps just repeated again for emphasis’. As with the rest of the book this compendium is delivered with a sense of humour that readily engages the reader. If I could change one thing about the book it would be the cover, which seems to me to be something of an afterthought; a more dramatic image of a landslide might better grab the reader's attention. However, as we all know, one should never judge a book by its cover (ahem!).

This short and accessible work is packed full of valuable insights, built up over a long and distinguished career, and a very entertaining read to boot. I recommended it unreservedly for anyone and everyone with even a passing interest in slope stability or landslides.