Dr. Sivaraj Shyam-Sunder
Acting Deputy Director
Building and Fire Research Laboratory
National
Technology Administration
Before the
Committee on Commerce, Science, and Transportation
Subcommittee on Science, Technology, and Space
National Earthquake Hazards Reduction Program
NEHRP has been an extraordinary, and often exemplary, collaboration between federal agencies, state and local governments, and the private sector.
During its first 26 years, NEHRP has contributed in very significant ways to reduce our nation’s vulnerability to the shakes, rattles, and rolls of earthquakes and NIST is proud to have been a part of that record of accomplishment.
While it is difficult to quantify loss prevention through
the adoption of improved mitigation practices, there is no doubt that NEHRP
products and results have contributed in significant ways to reduce the loss of
life and economic losses from earthquakes.
In addition, the loss of life from earthquakes in the
My testimony today will describe NIST current responsibilities and activities under NEHRP, how they will change if H.R. 2608 is enacted, our comments on those changes, and the extent to which NIST has the resources to carryout the new tasks. I have also provided as an attachment to the testimony a brief description of some of NIST’s most significant accomplishments supporting NEHRP research.
NIST Current
Responsibilities and Activities
NIST
is a natural participant in NEHRP because of its long-time role in providing
measurements, standards, and technology to help federal, state, and local
government agencies and the private sector protect the nation and its citizens
from natural as well as manmade threats.
Currently,
we have four major responsibilities:
1. To develop seismic design
and construction standards for consideration and subsequent adoption in federal
construction;
2. To assist federal, state,
and local agencies, research and professional organizations, model code groups
and others in developing, testing, and improving seismic design and
construction provisions to be incorporated into local codes, standards, and
practices;
3. To conduct research on
performance criteria and supporting measurement technology for earthquake
resistant construction; and
4. To participate in NEHRP
post-earthquake investigations and analyze the behavior of structures and
lifelines, both those that were damaged and those that were undamaged; and to
analyze the effectiveness of the earthquake hazards mitigation programs and how
they could be strengthened.
Early
in 2001, a NEHRP Strategic Plan was approved by each of the four participating
agencies. This plan identified a
technology transfer gap that limits the adaptation of basic research knowledge
into practice. The plan recommends an expanded
problem-focused research and guidelines development effort to facilitate the implementation
of new mitigation technologies.
As
a first step, NIST requested the Applied Technology Council to convene a
workshop of national leaders in earthquake design, practice, regulation, and
construction in July of 2002. The
purpose of the workshop was to assess the state of knowledge and practice and
to suggest an action plan to address the gap between basic research and
practice.
The
action plan identifies industry priorities in two areas:
(1) support for the seismic code development process through
technical assistance and development of the technical basis for performance
standards; and
(2) improved seismic design productivity through the
development of tools for the evaluation of advanced technologies and
practices.
The
action plan, “The Missing Piece:
Improving Seismic Design and Construction Practices (ATC-57),” is
available from the Applied Technology Council, www.atcouncil.org.
NIST
now looks forward to working with the stakeholder community to explore ways to
best meet those needs via a public-private partnership. We expect this effort will build on
NSF-funded basic academic research, including that conducted as part of the
George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES)
Consortium.
Our
current activities and recent accomplishments are as follows:
National Construction Safety
Team
In
the aftermath of the World Trade Center Disaster, Congress has given NIST the
authority to investigate major building failures in the
The
National Construction Safety Team (NCST) Act gives NIST the authority to
dispatch teams of experts within 48 hours following a major building disaster. Congress anticipated the NCST Act to be
applicable to building failures caused by earthquakes. The Act specifies that the NIST Director
develop implementing procedures that “provide for coordination with Federal,
State, and local entities that may sponsor research or investigation of
building failures, including research conducted under the Earthquake Hazards
Reduction Act of 1977.” In addition, the
Committee Report 107-530 published by the House Science Committee on June 25,
2002 states that “ The Director should clearly define how earthquake
researchers and Teams will carry out their responsibilities in a coordinated
fashion in cases where building failures have been caused by an earthquake.”
NIST’s
responsibilities under the NCST Act have been incorporated into the recently
completed plan to coordinate post-earthquake investigation issued by the four
agencies comprising the National Earthquake Hazards Reduction Program. The plan (USGS Circular #1242) states that,
within 48 hours, NIST will examine the relevant factors associated with
building failures that occur as a result of the earthquake and will make
reasonable efforts to consult with the other NEHRP agencies prior to
determining whether to conduct an investigation under the Act. Any NIST investigation conducted under the
Authority of the Act will be limited to building failures on one or more
buildings or on one class or type of building selected by NIST. NIST recently participated in a series of
tabletop exercises with representatives of the other NEHRP agencies. The exercises simulated the response to
earthquake scenarios in different parts of the
Interagency Committee on
Seismic Safety in Construction
NIST
chairs and provides the technical secretariat for the Interagency Committee on
Seismic Safety in Construction (ICSSC).
The ICSSC is composed of representatives from 32 federal agencies and
develops uniform standards of seismic safety for federally owned, leased,
assisted, and regulated buildings. The
ICSSC also provides guidance to the federal agencies on the use of industry
standards and codes for design and construction of federal buildings to meet
the standard of life safety established for federal buildings.
The
ICSSC issued Standards of Seismic Safety for Federally Owned and
NIST
staff serve on the Provisions Update Committee that drafts proposals for change
to the NEHRP Recommended Provisions for Seismic Regulations for
Currently
the ICSSC is conducting a project to update the NEHRP Handbook for Seismic
Rehabilitation of Existing Buildings.
The handbook is intended to provide practical guidance to design
professionals on the seismic rehabilitation of standard building types. The handbook will facilitate implementation for
federal buildings when a policy decision is made to proceed.
Prevention of Progressive Structural Collapse
NIST has initiated a project to develop and implement performance criteria for codes and standards, tools and practical guidance for prevention of progressive structural collapse. Progressive collapse refers to the spread of a structural failure – by a chain reaction – that is disproportionate to a localized triggering failure, often due to abnormal loads. Such collapse can result in a disproportionate loss of life and injuries. The project is considering four distinct but interrelated strategies to mitigate progressive collapse: (1) system design concepts, (2) retard collapse after triggering event, (3) built-in redundancy via alternate load paths, and (4) retrofit and design to “harden” structure.
A key focus of the project is to develop retrofit and design methods that take advantage of the synergies associated with mitigating progressive collapse under multiple threats (blast, impact, fire, wind, and earthquake). The project depends heavily on the development and use of advanced modeling and simulation tools to evaluate the vulnerability of structural systems to progressive collapse under different threats. The project is reviewing and using knowledge gained from controlled demolition technology and builds on that knowledge to develop effective mitigation strategies for progressive collapse. Finally, the project is developing performance criteria and methods to mitigate progressive structural collapse cost-effectively for both new and existing structures based on a combination of existing knowledge, the results of analytical model sensitivity studies, and laboratory and field measurements.
NIST
held a national workshop on Prevention of Progressive Collapse on
Fire Safety Design and Retrofit of Structures
NIST is using a multi-hazard approach to facilitate the development of mitigation technologies. In addition, building fires can often result following an earthquake.
The objective of this project is to develop significantly improved standards, tools, and practical guidance for the fire safety design and retrofit of structures. The project is focusing on standards and tools for steel and concrete structures and on verified predictive tools and performance criteria to evaluate structural fire performance in real fires.
Five key factors are being considered in developing performance-based methods:
(1) While the current standard fire endurance test method, which stipulates a prescribed time-temperature exposure, is adequate to compare relative performance of structural components, it does not provide any indication about the actual performance (i.e., load carrying capacity) of a component in a real fire environment (e.g., involving fire of building contents).
(2) The role of structural connections, diaphragms, and redundancy in enabling load transfer and maintaining overall structural integrity during fire is ignored in structural design. Current design methods are based on fire endurance tests of single components and do not account for the behavior of inter-component connections or the complex two- and three-dimensional behavior of the entire structure.
(3) There is a need to evaluate the effectiveness of alternative retrofit, design, and fire protection strategies to enhance structural fire endurance (including alternate cementitious spray or board systems, intumescent coatings, high-performance fire protective coatings, active suppression systems, and more sensitive sensing and monitoring). No practical, high-level models exist today that couple the fire dynamics to the structural system response, and the resulting transient, multi-dimensional heat transfer through structural components made with multiple materials.
(4) There is a lack of knowledge about the fire behavior of structures built with innovative materials (e.g., high-strength concrete or steel structures).
(5) There is a need to better model and predict the fire hazard to structures from internal and external fires. This includes deterministic and probabilistic models for specifying the magnitude, location, and spatial distribution of fire hazards on structures; determination of reliability-based load factors for combined dead, live, and fire loads and resistance factors for loss in structural strength and stiffness; and methods for load and resistance factor design (LRFD) under fire conditions.
The project will develop performance criteria and methods to assure cost-effective structural performance under fire for both retrofit and design applications based on a combination of existing knowledge from around the world, the results of analytical model sensitivity studies, and laboratory and field measurements.
H.R. 2608 National
Earthquake Hazards Reduction Program Reauthorization Act of 2003
If
H.R. 2608 is enacted, the roles and responsibilities of NIST in NEHRP will
change in the following ways:
(1) NIST will become the lead
agency for the program.
(2) The bill creates an
Interagency Coordinating Committee (ICC) for NEHRP with the NIST Director as
the Chair and the directors of FEMA, USGS, NSF, OSTP and OMB as the other
members. It tasks the Committee with
oversight, planning, management, and coordination of the program. The legislation also requires the Committee
to develop and periodically update a strategic plan for the program that
establishes the NEHRP goals and priorities and develop and submit to OMB a
coordinated interagency budget that will ensure appropriate balance among
activities.
(3) The bill directs the ICC to
transmit to Congress an annual report on the program at the time of the
President’s budget request. The report
should include the program budget for the current and upcoming fiscal years for
each NEHRP agency and a description of the activities of the program during the
previous year. It should also include
the effectiveness of the program in furthering the goals established in the
strategic plans and a description of the extent to which the program has
incorporated the recommendations of the external NEHRP Advisory.
(4) The bill requires the
Director of NIST to establish an Advisory Committee consisting of
representatives of research and academic institutions, industry, and State and
local government. It tasks the Advisory
Committee with assessing trends and developments in earthquake hazards
reduction science and engineering and the effectiveness of the Program. The Advisory Committee must report its
findings and recommendations to the Director of NIST one year after enactment,
and at least once every two years thereafter.
NIST
believes that the proposed changes to the Interagency Coordinating Committee,
adding representatives from the Office of Science and Technology Policy and the
Office of Management and Budget, and the formation of a Federal Advisory
Committee will serve to strengthen the NEHRP program. NIST has the experience and expertise to
perform the lead agency function for NEHRP
Mr.
Chairman, I want to thank you and the Subcommittee again for allowing me to
testify today about NIST’s activities in support of NEHRP and allowing us to
discuss our views on H.R. 2608. I would
be happy to answer any questions at this time.
Attachment A
Products and Results of NIST Problem-Focused R&D
Bridge Column
Reinforcing Requirements
Immediately following the 1971
NIST
initiated a project in the 1980s to provide the necessary verification,
consisting of two full-scale bridge column tests. The challenges arose from the size of the
test specimens and the need to apply horizontal seismic loads in addition to
vertical gravity loads. The series of
column tests was the first of its kind and as such, provided important
benchmark data. The tests also verified
the adequacy of the revised design specifications.
In
addition, NIST tested companion 1/6-scale bridge columns and the results
indicated that the behavior of full-scale bridge columns could be extrapolated
from small-scale bridge column tests.
This finding suggests that high costs associated with full-scale tests
are not always necessary and less expensive small-scale tests may be
sufficient.
Welded Steel Moment Frame
Connections
Steel
framed buildings traditionally have been considered to be among the most
seismic resistant structural systems.
The January 17, 1994, Northridge Earthquake, however, caused unexpected
damage to many welded steel moment frame buildings. In general, the damage was confined to
beam-to-column connections that suffered brittle fracture in the flange
welds.
In
response to these failures, NIST initiated a project to study methods to modify
existing buildings to improve their seismic performance, in collaboration with
the American Institute of Steel Construction, the
The
result of this multi-year effort was the publication of comprehensive
guidelines for seismic rehabilitation of existing welded steel frame buildings
as an AISC Design Guide. The guidelines provided experimentally-validated
response prediction models and design equations for the three connection
modification concepts that shift loading from the welded joints into the beams,
thus enabling the structure to absorb the earthquake’s energy in a non-brittle manner.
Test Methods for Structural
Control Devices
Structural
control devices, such as seismic isolation and passive energy dissipaters, have
been installed in numerous structures throughout the world and have proven to
be effective in reducing both motions and forces during earthquakes and strong
winds. Still these devices are generally
produced in small quantities, specifically for each application.
To
guarantee that the devices will perform as the designer expected, many building
codes and guidelines recommend that the devices be tested before
installation. While some of these
standards describe a limited number of specific tests, widely accepted test methods
did not yet exist at the time of this project.
Such standards are useful to designers, manufacturers, and contractors,
since they will make the process of validating these devices consistent.
To
address the issue NIST has developed two sets of testing guidelines. The Guidelines
for Pre-Qualification, Prototype, and Quality Control Testing of Seismic
Isolation Systems was issued in 1996.
ASCE has developed and is currently balloting a national consensus
standard based on the NIST-developed isolation device testing guidelines.
While
seismic isolation is generally accepted in earthquake engineering practice and
recognized in the building codes in high-seismic areas, passive structural
dampers are still gaining acceptance and semi-active devices are still in the
development phase. NIST has just issued Guidelines for Testing Passive Energy Dissipation
Devices.
S. SHYAM SUNDER
Acting Deputy Director
Building and Fire Research Laboratory
Dr. Shyam Sunder is Acting Deputy Director of the Building and Fire Research Laboratory (BFRL) at the National Institute of Standards and Technology (NIST).
BFRL’s mission is to meet the measurements and standards needs of the building and fire safety communities by serving as the source of critical tools – metrics, models, and knowledge – used to increase productivity, facilitate trade and enhance public safety through technical innovations and improved codes, standards, and practices. New construction and renovation amount to over one trillion dollars annually – about 12 percent of U.S. GDP – and unwanted fires cost the economy over $100 billion annually. Everyone’s safety and quality of life and the productivity of all industries depend on the quality of constructed facilities.
BFRL has an annual operating budget of about $39 million and its staff includes about 180 federal employees and 100 research associates and guest researchers from industry, universities, and foreign laboratories.
In his current position, Dr.
Sunder also:
·
serves as the
lead investigator for the federal building and fire safety investigation into
the
·
oversees NIST
activities related to the National Construction Safety Team Act;
·
leads NIST
activities related to the National Earthquake Hazards Reduction Program
(NEHRP);
·
guides effective
implementation of the NIST strategic plan within BFRL and the four BFRL goals:
Homeland Security, Fire Loss Reduction, Enhanced Building Performance, and
High-Performance Construction Materials and Systems;
·
chairs, as
designated by the NIST Director, the Interagency Committee on Seismic Safety in
Construction (ICSSC) – a group that
recommends policies and practices to its 32 member-agencies on improving
the seismic safety of federal buildings nationwide; and
·
serves as the
U.S.-side chair of the Wind and Seismic Effects Panel established under the
U.S.-Japan Cooperative Program on Natural Resources (UJNR).
Dr. Sunder was chief of the
Structures Division from January 1998 until June 2002 and chief of the
Materials and Construction Research Division from June 2002, when the Building
Materials Division was merged with the Structures Division and renamed, until
March 2004. From June 1996 to December
1997, Dr. Sunder was on assignment to the Program Office, the principal staff
office of the NIST Director, first as a Program Analyst and later as the Senior
Program Analyst for NIST. In 1994, Dr.
Sunder joined NIST’s Building Materials Division as Manager of BFRL’s newly
created High-Performance Construction Materials and Systems Program and served
in that position until June 1996.
Prior to joining NIST, Dr.
Sunder held a succession of positions at the Massachusetts Institute of
Technology (MIT) beginning in 1980: instructor, assistant professor, associate
professor, principal research scientist, and senior research scientist.
Dr. Sunder’s awards include the Gilbert W. Winslow Career Development Chair (1985-87) and the Doherty Professorship in Ocean Utilization (1987-89) from MIT, the Walter L. Huber Civil Engineering Research Prize (1991) from the American Society of Civil Engineers, and the Equal Employment Opportunity Award (1997) from NIST.
Dr. Sunder holds a Bachelor
of Technology (Honors) degree in civil engineering from the Indian Institute of
Technology,