CHAPTER 5
SELECTION OF SITE-SPECIFIC STABILIZATION TECHNIQUES
This chapter presents a rational approach to the solution of site-specific bank
stabilization problems. It is assumed that application of the insights and analyses presented
in the first three chapters has led to the identification of the causes and mechanisms of bank
instability. It is also assumed that the conceptual analysis described in Chapter 4 has
determined that site-specific bank stabilization is to be a project component, perhaps the only
component. Selection of a stabilization approach logically follows that determination, and
logically precedes preparation of the detailed project design discussed in Chapters 5 through
9.
The reader might logically question why detailed descriptions of alternative
techniques, and their advantages, disadvantages, and typical applications, are not discussed
in this chapter rather than later in the text. The author's dilemma was that those topics are
even more integral to the design concepts discussed later in the text than to selection of
techniques. The discussion, therefore, follows what seems to be the most efficient and
comprehensible format overall. Because it is impossible to neatly segregate all topics, some
redundancy is unavoidable, but an attempt was made to minimize it. Hopefully the dilemma
proves to be less painful in practice than it is in concept, because all pertinent material should
be examined by the reader, regardless of its location in the text. Also, some readers will
already be familiar with many techniques, and even those readers who are not experienced in
bank stabilization will find that one can intuitively grasp many concepts of selection without
a tedious search through the text for supporting material.
A framework for selection can be expressed by "Three E's":
Effectiveness of alternative approaches;
Environmental considerations; and
Economic factors.
The rationale for using this framework is that inherent factors in the properties of a
given bank stabilization technique, and in the physical characteristics of a proposed worksite,
influence the suitability of that technique for that site. It is essential here to distinguish
suitability, which is governed by those inherent factors, from adequacy, which is governed
by design decisions. In other words, the selection phase focuses on suitability, while the
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