Better Bridges: Getting Over a Big Problem
By John Latta
er I-85 leads to
temporary overpass ov
mps for roadbuilders
temporary median onra
T’S NOT EITHER END OF THIS BRIDGE THAT IS ITS MOST IMPORTANT
ENTRANCE/EXIT POINT. IT’S THE MIDDLE.
That situation occurs because when you contract to
add lanes to a divided Interstate using the median for the
new roadway, you have a number of problems to solve,
but one really, really big one. Access. But if you think innovatingly, let’s say daringly, enough, you don’t have do
the work predictably.
The I-85 widening project in Cabarrus County, N.C.,
involves the widening of approximately 8 miles of aging
and deteriorated Interstate with complete replacement of
all pavement and six bridges. The job was design-build
and contractor Lane Construction came up with an out
of the box, stunningly simple and innovative temporary
bridge - with median acces ramps - concept.
“The majority of the new roadway width is being constructed in the existing 70-foot median, creating a very
26 August 2012 Better Roads
difficult access challenge and potentially severe safety concerns for the travelling public,” says a Lane spokesperson.
“These challenges are typical on Interstate widening projects yet they are always difficult to overcome. The need
for an innovative work zone traffic control and access
plan is particularly critical on this design-build project
due to the severe state of deterioration and Average Daily
Traffic of over 100,000.
“Unimpeded access to the existing median is critical to
improve safety, minimize impacts to traffic, reduce stress
on existing peripheral infrastructure, accelerate the project
schedule, and reduce cost of construction by increasing
NCDOT resident engineer Davis Diggs says the bridge
wasn’t in the RFP but Lane delivered a technical proposal