Page 6 - Advanced Design Examples of Seismic Retrofit of Structures
P. 6
Preface
Earthquake vulnerability of buildings has been acknowledged across the globe
with many examples of seismic damage in China, India, Latin America, and
Europe as well as the United States. Much attention has been focused on this
topic worldwide from both societal and engineering perspectives. As a result,
a significant amount of development work has been carried out to evaluate var-
ious assessment methodologies and evaluate possible retrofit methods. The
main challenges in seismic retrofit are usually attributed to understanding the
available codes requirements, modeling assumptions, methods, and retrofitting
schemes.
Seismic retrofit of structures covers a broad range of structural types and
retrofit methods, and hence it is more complex than designing new buildings.
It is quite likely that two very different retrofit methods may be proposed for a
single project by two different consulting engineers. Even the details of a unique
retrofit technique may differ for a single project by different design engineers.
Part of this variety originates from the design and implementation ambiguities
regarding retrofit projects. Compared to designing new buildings, retrofitting
has never been an undergraduate or graduate compulsory course; and there
are fewer retrofitting projects than there are new buildings being constructed.
As a result, experience in the design and implementation of retrofit projects
is very limited compared to ordinary construction projects. Although there
are good retrofit codes available to professionals, experiences prove that the
engineers’ “interpretations” of these codes may vary a lot. Therefore, there is
a need to elaborate the concepts of design and the construction details of retrofit
projects. In response to this need, the current book tries to present some real
projects that can be regarded as good representatives of different retrofit pro-
jects with the emphasis on dealing with ambiguities, questions, and difficulties
in design and construction.
The idea for this book started some years ago with university students and
industry colleagues, with the goal of facilitating the use of design codes related
to seismic retrofit of common structures. Beginning with the introduction of
concepts and approaches, this book aims at presenting several examples of real
retrofitting projects that cover a broad range of structural systems and retrofit-
ting methods. In-depth design calculation procedures are found in each example
and the reason behind the selection of a particular method or assumption is
elaborated. The book not only provides a valuable source for previously
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