ACPA Concrete Pavement Progress Q2 2020

Delaware DOT Leads the Way with Weekend Intersection Reconstruction Long-lasting concrete intersection keeps traffic moving By Sheryl S. Jackson KEEPING TRAFFIC MOVING SAFELY THROUGH and near construction zones is a common challenge, but the Delaware DOT (DelDOT) has adopted a strategy the agency and contrac- tors have used successfully for many years. About 15 years ago, when DelDOT officials first considered reconstructing an intersection in one small town, they quickly realized the steady flow of truck traffic to and from a ready mixed concrete plant on the edge of town was a factor. The steady stream of trucks hauling sand, stone, and cement to the plant, as well as ready mix to jobsites was necessary, but also presented challenges. “The original pavement was asphalt and the combination of a 25 mph speed limit and the signalized intersection into which the trucks turned stressed the pavement and caused se- vere rutting,” explains James Pappas, deputy director of operations and support for DelDOT. Previously, the agency had different strategies for intersection reconstruction, including removal of 4 in. of asphalt and rehabilitation with thin bonded concrete overlays, but there were problems with uncontrolled reflective cracking. “Based on our previous attempts with both asphalt and concrete overlays, we decided to reconstruct the intersection with full-depth concrete,” says Pappas. Following extensive coring and soil boring to determine the con- dition of the subbase and base, the decision was made to shut the intersection down for a full weekend to remove the existing pavement and replace it with 12-in. concrete pavement. The success of the first full-depth concrete intersection reconstruction has led to Del- DOT’s use of the strategy for repair of many intersections throughout the state. “This is standard operating practice for us because it provides a long-term solution for high volume and high stress intersections,” Pappas says. I N T E R S E C T I O N R E C O N S T R U C T I O N Concrete Pavement Progress www.acpa.org 12