“We just wanted to ensure that we had experienced personnel
– and enough personnel out there – and that they’d be capable in
handling a new process,” Weiss said.
WisDOT is already considering future uses for pre-made
concrete panels, perhaps in larger cities like Milwaukee or
Madison, where traffic is more of an issue and work windows are
shorter.
“It’s a more expensive product to use, so it needs to be in
certain situations,” Weiss said.
Alternatives broken down
Lisa Fleming, who managed the project for Ayres Associates,
outlined the differences between the two joint repair methods.
“Traditional joint repair, or cast-in-place, is where you saw
the pavement, remove the slab, put in your dowel bars that transfer
the load, and pour the concrete back in place. Then we open up
to traffic the next day,” Fleming explained. “The precast ones are
made off site at another location and then, at night, you install
them. You remove your joint, prep it, and you insert the panel. You
can either grout it in place that night or do it on another night.”
While upfront costs are higher with precast panels and the
amount of work time is similar to the cast-in-place approach, the
chief advantage is the product’s longevity. Over their life cycle,
precast joints last twice as long, thereby eliminating the need for a
second round of repairs and the associated disruption to motorists,
the cost of engineering, and staged traffic control, Fleming said.
Innovation at work
The precast panels are constructed in a factory under a
controlled environment – in this case, Wieser Concrete of Maiden
Rock, Wisconsin – unlike cast-in-place concrete, which is poured in
the field and susceptible to weather as it cures.
The precast joint repair process also is expected to last twice
as long as cast-in-place joints – a major advantage for metro areas
with high traffic volumes.
Andy Wieser, president and co-owner of the concrete products
manufacturer, explained the process involved and how each of the
210 panels was evaluated individually – custom-manufactured to
each segment needing repair.
“The contractor goes out to the project, and they measure each
spot that they want to replace. They lay it out, and they measure
it, and then we make each slab to fit those measurements,” Wieser
said. While some slabs were the same, others were an inch longer
or shorter, he said.
Once created, Wieser then numbered the slabs in sequence and
coordinated their placement on the truck for hauling to the job site.
“There was coordination there with the trucking to make sure
we had them stacked properly so when they picked them off they
weren’t having to handle them – so everything from production to
delivery to installation is all sequenced to match that location on
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