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Integrated Seismic Rehabilitation
progress has been made in the development of techniques for the
seismic evaluation and rehabilitation of existing hazardous buildings
as a result of the National Earthquake Hazard Reduction Program
(NEHRP) and the NEHRP documents noted above. However, there are
still significant barriers to the implementation of seismic rehabilitation.
Initial cost, loss of normal use, and uncertainty of cost recovery
have been the principal obstacles to seismic rehabilitation investment.
The concept of Incremental Integrated Seismic Rehabilitation is
specifically designed to reduce the obstacles of high initial cost
and the cost of service interruption. Integration of seismic rehabilitation
into the normal cycle of building operation and maintenance significantly
reduces the cost of work specifically assigned to seismic rehabilitation
because in many maintenance procedures scaffolding and other construction
equipment are in place, work surfaces are exposed, and use interruptions
are accommodated. Incremental phasing of seismic rehabilitation
significantly reduces the obstacle of initial cost and allows for
the accomplishment of improved seismic safety over a period in which
it may be accommodated in maintenance budgets or as an increment
of normal capital improvement. An incremental approach is a reasonable
response to the uncertainty of cost recovery. This is because the
seismic risk is probabilistic over time, as a function of earthquake
recurrence periods, and so are the benefits of the reduction of
is important to recognize that "the normal cycle of building
operation and maintenance" referred to in the preceding paragraph
may vary with organization type and occupancy category of the buildings.
In the case of schools, based on case studies that delved into the
actual experience of school districts, it was possible to categorize
"the normal cycle of building operation and maintenance"
into eight broad categories:
maintenance and repair/re-roofing.
walls maintenance and repair/window replacement.
and life safety improvements.
and basement maintenance and repair.
analysis will be carried out for each use category in the proposed
Integrated Seismic Rehabilitation recognizes that financing and
administration are determining factors in the accomplishment of
earthquake safety that are as important as design and construction.
The modification of rehabilitation strategies to accommodate administrative
and finance practices in the organizations which make investment
decisions for mitigation is an important new dimension in implementing
approach proposed consists of five basic parts that are summarized
the concept's validation and currency---The NSF funded conceptual
development of the Incremental Integrated Seismic Rehabilitation
approach drew on the experience of selected school districts in
the early 1990s. Research findings from this study were documented
and enjoyed limited prototype application. It is now appropriate
to evaluate and update those initial findings and recommendations
for broad application nationally. The proposed approach is described
more fully as Task 3, and consists of four parts: Empirical Validation,
Analytical Validation, Benefit/Cost Validation, and Currency Validation.
the basis for selection of other occupancies---In the NSF project,
the applicability of the Incremental Integrated Seismic Rehabilitation
concept to school buildings was based on the favorable condition
of three sets of generally shared characteristics:
Building type/structural characteristics
there is clearly variation in each of these sets of characteristics
over the national stock of school buildings there has proven
to be adequate commonality to allow useful generalization in
the development of rehabilitation process models and the identification
of specific rehabilitation opportunities. In terms of occupancy/use
characteristics, most lower, middle and upper schools in the
United States contain similar aggregations of spaces and spatial
relationships and similar patterns of use. In terms of building
type/structural characteristics, most school buildings in the
United States are one to four stories in height, have a relatively
high ratio of floor area to perimeter wall area and share several
seismically vulnerable structural characteristics that are a
function of when they were built (for example, unreinforced
load-bearing masonry, and precast concrete roof elements over
long-span spaces such as gymnasiums). In terms of institutional/organizational
characteristics, most public school districts in the United
States have similar organizational structures and similar methods
order to apply the concept of Incremental Integrated Seismic
Rehabilitation to occupancies and contexts beyond schools, we
propose to examine the clustering of various occupancies within
a 3-dimensional matrix with the three sets of characteristics
on the respective axes. We propose to start this matrix analysis
with occupancy types for which seismic safety is a high societal
priority: emergency facilities, nursing homes, office buildings,
of information pertinent to other occupancies -- The approach
proposed for this task is to obtain information from the respective
trade and professional associations concerned with each occupancy.
The information will not be obtained by means of the distribution
of survey instruments. This information will be validated and
reinforced on the basis of actual seismic rehabilitation experience.
of manual -- The manual will lay out the general concept of Incremental
Integrated Seismic Rehabilitation, and will include targeted sections
for each occupancy type. Each section will address two specific
audiences within each of the occupancy/use categories: policy
makers and senior executives, and facility and risk managers.
of dissemination plan -- The approach proposed is to develop the
dissemination plans in close collaboration with the respective
trade and professional associations concerned with each occupancy