Section B. Project Summary
NEESR-CR: Mitigating Seismic Damage and Environmental Impact through Innovative
Composite Walls: A New Approach
Structural engineers must contribute to achieving society’s sustainability goals by reducing the
environmental impact of the systems they design. To do this, new structural systems must be developed
that will transform design practice and integrate seismic performance objectives with minimized
environmental impact. Such systems should minimize material use, CO2 emissions, construction
schedules and labor; maximize use of recycled materials and simultaneously achieve exceptional seismic
performance. Here, a composite wall system composed of recycled, CO2 emission reducing materials,
specifically a structural steel shell filled with concrete utilizing supplemental cementitious material
(SCM), is proposed. The constructability is enhanced relative to conventional concrete walls and labor is
reduced by eliminating the wall’s steel reinforcement and formwork, and using self-consolidating
concrete (SCC). Concerns regarding construction and loading during the elongated cure time of SCMonly concrete will be addressed by the presence of the steel skin plates, which will sustain these loads.
Wall details will be developed with an eye towards delaying buckling and foundation damage, ensuring
reduced post seismic event repair costs. The research approach is to use three coordinated experimental
tasks to develop the primary material, component and wall technologies. Analytical research techniques
will extend the experimental findings and establish engineering design methods. Integrated practitioners
within the research team will ensure practical technology development and transfer.
INTELLECTUAL MERIT: The proposed system will transform the notion of environmental
stewardship in structural engineering. To develop it, a team has been assembled that includes researchers
with expertise in SCM concrete, the seismic behavior of concrete, steel, and composite structural
components, and large-scale structural experimentation, as well as practitioners from the sustainable
structural engineering community. The research will utilize the state-of-art nees@Buffalo facility to test
several full-scale double skin composite walls with high cement replacement concrete, representing the
first large-scale tests of this system under reversed cyclic loading in the world and the only experiments
utilizing SCM concrete. To support the design of the large-scale specimens, the SCM concrete will be
characterized using conventional and innovative material testing procedures at Seattle University (SU)
and Lefarge North America. Experiments will be conducted to establish a robust yet constructible footing
connection and study the time-dependent response of the composite wall just after casting. These results
from the three experimental test programs will be combined with and extended by numerical studies.
Finally, the team will partner with leaders in sustainability in structural engineering from Walter P. Moore
to begin to establish PBEE tools and to develop sample building designs to compare the environmental
impact and seismic performance of the proposed and conventional system.
BROADER IMPACTS: Today, environmental stewardship in structural engineering involves forcing
current structural systems into LEED or other certification programs. This research will help to transform
the way structural engineers view their role in this national priority. Through direct integration of key
partners from industry, who hold leadership positions in the SEI committee on sustainability and the
AISC TC-9 committee on seismic design, the project results will be directly disseminated to, and have an
impact on, the structural engineering profession. Educational impacts will be integrated throughout the
research program by: (1) integration of undergraduate students from a predominantly undergraduate
institution (SU) directly in the experimental research activities and from their collaborative work with
graduate students at the UW and at University of Buffalo (UB), (2) summer research experiences at UB,
(3) WebEx based research integration meetings with all students from UB, UW, and SU. The major
outreach activity will be aimed at engaging young people in engineering. In collaboration with an
educational consultant, an array of educational tools for dissemination to teachers will be developed to
enable teaching and learning about the science, excitement, and challenges of designing structures for
earthquakes while remaining “green”.
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