Drivers negotiating the mountainous terrain of I-81 in the Virginia Department of Transportation's Salem District have had some hair-raising moments through the years.
In some sections, tractor trailers traveling 25-35 mph attempt to merge with drivers traveling 70 mph or more. In other sections, drivers feel uneasy driving close to canyon walls with rocks threatening to dislodge and come bouncing down the ledges into their traffic lanes.
Virginia Department of Transportation photo
VDOT engineers and workers give special consideration to these issues on this section of interstate through the I-81 Corridor Improvement Program (Improve 81) that analyzes problems and has a dedicated funding source to help fix them. Dave Covington is the I-81 program delivery director. Covington and his team of engineers, including planners, and hard-working contractors have devised practical solutions to these challenges.
Covington and his team have devised an economical solution to the falling rock scenario. Much like mountain climbers, the workers scramble up the steep embankments and drill anchors into the rock faces to secure “rock drapes.”
VDOT and workers will secure the rock drapes at the top of slopes, directing any rocks that dislodge into a ditch rather than into travel lanes. Covington outlined the strategy to Construction Equipment Guide by saying, “The rock drapes are a heavy metal fencing that will dissipate energy of any falling rock and will keep the public safe,” he said. “The contractor used a crane and other equipment to deliver the rock drapes to the tops of the hills.”
The lengthy acceleration lanes and deceleration lanes will add important safety factors where the highway crosses the New River. The road also has an interchange serving the city of Radford, which is becoming more industrial, meaning additional truck traffic is accumulating.
“Nothing is flat in this area,” said Covington. “Most of these roads were constructed in the 1960s and 1970s and have not been upgraded. At exit 105, the road crosses the river with steep slopes on the right of the northbound lanes. It looks intimidating. The new acceleration lanes will make the approach to the freeway much safer.”
Covington has the data to support the construction of the lanes and believes it will lead to fewer accidents.
“Extending the acceleration and deceleration lanes provides enough distance for vehicles, especially heavy trucks, to accelerate and reach near mainline traffic speed to merge.”
The new lanes are built of asphalt and will match the I-81 surface. The shoulders have been widened and a ditch constructed. Already in use, the new lanes have significantly reduced accidents at these trouble spots.
Virginia Department of Transportation photo
VDOT's Salem District is supervising more traditional work between exits 137 and 141, adding a third lane for both northbound and southbound traffic. Archer Western is the contractor for this work.
A big challenge for this project is to build eight bridges in just a 5.2-mi. section. Contractors and builders have had their work cut out for them to get the construction done while keeping the traffic flowing.
“The contractors and builders also had to manage extensive erosion control and stormwater management,” said Covington.
The construction team built two new bridges over Route 112, two new bridges over Route 619 and two more new bridges over Route 635 (Goodwin Avenue).
Virginia Department of Transportation photo
The team widened two more bridges over Route 311 and repaired the decks of these bridges. Most of the bridges were short spans. The workers installed reinforced concrete girders for those bridges. The contractor also installed another safety device: constant slope barriers. These concrete and steel walls prevent trucks from crossing through medians and into oncoming traffic during an accident. The devices also help prevent trucks from turning over in collisions.
Covington believes that drivers and the state are getting excellent value for the $200 million spent on these projects.
“This is a massive benefit to the traveling public,” he said. “Traffic volumes are steadily increasing in this area from just a few years ago. Some of these lanes are already operational, and we are getting great feedback on their usefulness from drivers.”
