Geotechnical failures, specially the catastrophic ones, are a stimulus
to improve current understanding of phenomena and procedures and tools
for analysis and prediction.
This unconventional approach to geomechanics is the essence of this
book. In general, soil mechanics and geotechnical textbooks describe
first the concepts and theoretical developments and then apply them to
interpret or solve a particular applications. This book follows a
different course. The case (a failure) is first described and then an
explanation is sought. This requires a set of steps which can be
summarized as follows: Identify the nature of the problem, develop a
dedicated and specific formulation of the case, based on established
basic concepts. In general, no single existing theory or procedure is
available to solve the case at hand, provide a solution within an
acceptable degree of complexity, extract the fundamental aspects of the
problem and highlight its relevance.
The cases selected have been grouped into three main topics: Landslides,
Embankments and Dams and Dynamics of Failures. Cases selected (Vaiont,
Aznalcóllar, Brattas-St. Moritz) are unique and illustrate a number of
relevant and to some extent controversial issues which are of wide
interest, without claiming exhaustive treatment of the subject.
The book teaches how to build the necessary models to understand the
failures. Well established soil mechanics concepts are the necessary
background. But the cases analyzed require in general a step ahead which
is specific for the case analyzed. Balance and equilibrium equations are
often required as a starting point. They are formulated at different
scales, which are selected having in mind the abstract representation of
each case.
Various chapters illustrate also the coupled nature
(flow-deformation-temperature) of geotechnical problems and the need to
properly address these complexities in some cases. In fact, temperature
effects, a subject often neglected in conventional analyses, are
necessary to explain some catastrophic landslides (Vaiont). In some of
the chapters, specific calculation tools, included in well known and
widely available programs (Excel, Maple...) have been used. Details of
the ad hoc programs developed have also been included in Appendices to
help the readers to follow the details of the calculation.
Finite element methods have not been used. In the landslides analyzed
(Vaiont and Brattas-St. Moritz) currently available commercial programs
are of limited utility. In the remaining cases the analysis performed
provides a sufficient insight and interpretation of field behaviour.
Chapters include also a short description of the changes in the original
design and the mitigation measures which could have prevented the
failure. Also, a summary section of lessons learned is provided in all
chapters. Finally, selected topics and more advanced reading are
suggested.
This book is associated with a Master/Doctorate course being offered at
the Department of Geotechnical Engineering and Geosciences of UPC,
Barcelona. Potential readers therefore include Graduate and Master
students, faculty and professionals in the fields of Civil and
Geotechnical Engineering.
