Recognized as a leader in accelerated bridge
construction (ABC), Iowa’s Department of Transportation
(IDOT) was asked to partner with HNTB
Corporation to demonstrate the viability of a
high-performance ABC concept being developed
as a standard for nationwide use. The project
included the replacement of the Keg Creek Bridge
on U.S. 6 in Pottawattamie County, Iowa. The
bridge, a steel/precast modular structure 47' wide
and 210' long, would be completely replaced in a
two-week traffic-closure period. Normally, such
an undertaking would require complete or partial
road closure for a period of months.
In addition to an aggressive construction schedule,
the project strove to incorporate innovative
construction methods that could be easily replicated
with other bridges throughout the U.S. As
IDOT and HNTB explored available options, they
discovered that Dayton Superior’s Sleeve-Lock
grout sleeve, a cementitious grout-filled, onepiece
mechanical coupler designed to butt-splice
reinforcing steel in concrete structures, could
provide the strong connections required in a
minimal amount of time.
“Iowa DOT was charged by the National
Academy of Science to replace a bridge in
the shortest amount of time possible. So, we
evaluated the best products and methods in
the industry when we discovered Dayton Superior’s
Sleeve-Lock Grout Sleeve. By tailoring
our processes to use a grouted sleeve in construction,
we were able to replace the bridge
while only having traffic closed for 2 weeks
instead of 16 weeks. The overall construction
project was shortened from 6 months to 2
months,” explained Michael D. LaViolette, PE
of HNTB Corporation