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At the National Concrete Bridge
Council(NCBC)/Post-Tensioning Institute (PTI)
2004 Concrete Bridge Conference, Charlotte, North Carolina May 15
- May18, 2004, Mr. Baumann will present the following paper
ADVANCES IN BRIDGE DESIGN AND CONSTRUCTION USING RECENT IMPROVEMENTS IN
RAPID CONSTRUCTION OF TALL SEISMIC RESISTANT BUILDINGS IN CALIFORNIA
By :
Hanns U.
Baumann, S.E.
Baumann
Research and Development Corporation
510 Avenida de
la Estrella, Suite K, San Clemente, CA 92672 USA
Tel: (949)
361-0888 Fax (949) 361-0868
E-mail: hanns@bautech.com
ABSTRACT
The economic
need to rapidly design and construct tall earthquake resistant buildings in
California, USA, has resulted in advancement of both design and construction
technology for concrete bridges. After extensive development and testing
for more than a decade, the world’s tallest precast concrete building in a
zone of highest seismicity, a 39-story building, has been construction in
San Francisco, using a new type of concrete reinforcement, Welded
Reinforcement Grids (WRG), that saves cost, time and labor. Also in San
Francisco is a recently completed 42-story building that, by using the WRG
reinforcement system, replaced 32 separate pieces of conventional
confinement reinforcement with one-piece WRG.
A 1.2 million
S.F. 24-story building in Long Beach, California USA is being constructed
with 75% reduction of labor with the rapid assembly of WRG reinforcement
cages.
Testing at
five universities and national laboratories of Canada and the USA has shown
that structures, when designed with this new reinforcement, will have little
to no damage during a violent earthquake. The tests also proved that the
structures, designed using the new WRG reinforcement product, required
significantly less concrete and reinforcement steel.
The success of
the Welded Reinforcement Grids in tall California earthquake resistant
buildings has caused a great interest by structural engineers in their use
in other types of structures. Fatigue testing of WRG in Lightweight High
Performance Concrete (LHPC) is planned in preparation for use of WRG in LHPC
in segmental bridges where the dimensional accuracy of ±1/8” (3mm) allows
use of automation of the WRG reinforcing cage assembly.
KEY WORDS
Welded
Reinforcement Grids, WRG, Earthquake Resistant, Rapidly Construct, Tall
Earthquake Resistant Building, Reinforcement Steel, Precast, Segmental
Bridges, Bridge Construction
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