Geoscience Reference
In-Depth Information
5. Emerging trends in design
Emerging trends in design further developed along the line of performance-based design
may be summarized as follows.
5.1. FROM DESIGN-FOR-CONSTRUCTION TODESIGN-FOR-PERFORMANCE
The concept of operational damage introduced in the performance-based design plays
a significant role in emerging trends in design. In conventional design, construction of a
goodgeotechnicalworkwasthesoleobjectiveofdesign.Intheemergingtrendsindesign,
providing appropriate function and service rather than a physical construction becomes
thefinalobjectiveofdesign.Thereisanimportantparadigmshiftfromstructure-oriented
to performance-oriented approach.
5.2. FROM STANDARDIZED-DESIGN TO SITE-SPECIFIC-DESIGN
Conventional design relied on the standardized earthquake loads such as those speci-
fied by design spectra and seismic coefficient. If needed, variability of these loads was
considered in a framework such as reliability design methodology but the loads were
standardized. In the merging trends in design, site-specific earthquake motions are used
for achieving theoptimum design best suited for the construction site.
5.3. FROM ANALYSIS-OF-STRUCTURAL/FOUNDATION PARTS TO
ANALYSIS-OF-SOIL-STRUCTURE SYSTEM
Conventional design was based ontheanalysis of structural or soilpart idealized to fit to
the simplified methodologies. In the emerging trends in design, analysis of whole soil-
structuresystem and identification offailure modes are the bases.
In fact, these emerging trends in design are incorporated in the International Standard
(ISO) onseismicactions for designing geotechnical works (Iai, 2005).
5.4. FURTHER EMERGING TRENDS: PRODUCING SERVICE
The discussions on these emerging trends in design can be extended further. By expand-
ing the concept of performance-oriented approach, a new horizon of design will become
apparent.Insteadoftryingtoreducethecostforconstruction,thenewobjectiveofdesign
will be to increase the service produced by the designing process. Instead of construct-
ing buildings and producing goods and works based on the concept of production effi-
ciency through mass production process and ending up producing unnecessary products
and infrastructures, the new objective of design will be to offer performance and service
required by the society.
The concept of offering performance and service further triggers us to have a new look
at civil engineering structures. Instead of trying to optimize individual structures for
