Crumbling Concrete Concerns Prompt Night-Time Repairs

With more than 140,000 cars and trucks zooming past each day, road crews in Jefferson County, AL, are working after hours to improve conditions on a portion of Interstate 59 in Birmingham. Repairs on the 3.22-kilometer (2 mi.) stretch of I-59 from the Civic Center Bridge to the Railroad Bridge just north of Tallapoosa Street began last summer and will continue for at least the next few months.

“The existing concrete pavement had deteriorated to a point where something had to be done to establish friction, for safety purposes. We’re using the new Novachip for this assignment. It involves placing an over lay over the concrete. In order to do so, we have to repair some of the spalls in the existing concrete,” explained David Hand, assistant division construction engineer with the Alabama Department of Transportation.

The biggest challenge of the $3.5-million project is making the repairs at night.

According to project engineer U.R. Buchanan, “We’re working from 7 pm - 6 am. We have to use electric generators to run lights, so we can see what we’re doing. It’s more trouble to check and watch what is going on because of limited vision. We also have to place message boards one mile before the construction work area and we have to post signs alerting motorists to lane closings. We’re using drums to comb off the area. The biggest problem with traffic control itself is setting it up for the ramps at the expressway. There’s a bottleneck for motorists where it goes to two lanes. We also have to watch out for drivers who are not paying attention or who are speeding. The state troopers on hand are able to help us in that respect.”

Once precautions have been taken, a crew of 13 must remove the concrete using a Komatsu rubber tire loader. Replacing the concrete slabs also requires the use of a John Deere 310 backhoe to handle the drill rig, which is powered by a 375 air compressor. Once the concrete is removed, dump trucks haul the material off site.

Another challenge for crews is the cold weather that Birmingham has experienced during the winter months.

“Of course, you can’t pour concrete when it’s freezing. We are supposed to stop pouring at 40 degrees and below. If the temperature gets too low, the concrete freezes and it would be impossible for it to bond with the existing concrete,” explained Buchanan.

Mother Nature permitting, crews are able to work at a fairly quick pace on this job. A fast-setting cement with a special additive is used, so it sets within a matter of hours. That allows vehicles to return to the road in less time.

“We work two or three holes and move forward from there. We’ve completed the inside two lanes and are now doing the outside lanes northbound. Then we’ll move on to the southbound lanes.”

The project also includes minor bridge end slab rehabilitation, along with the addition of new guardrails and traffic stripes. The most significant step, however, is the Novachip resurfacing.

“It’s the final stage of the process, and it’s something that’s fairly new for us. A grinder is used to take off the existing microseal. The Novachip material, which comes from steel mills, is put down approximately .5 to .75-inch thick. It has tremendous lasting power. The material used for bonding is much better than normal material,” added Buchanan.

“We put microseal down five or six years ago, and it’s wearing off pretty bad. The Novachip has been tried in other areas and it’s had very good results,” he continued.

The general contractor for the assignment is Good Hope Contracting Company Inc. in Cullman, AL. Subcontractors include Pinkerton Construction, Alabama Traffic Systems Inc., Statewide Grassing, Inc. and Alabama Guardrail Inc.


You can also view previous issues of Superintendent's Profile.