Down to Dirt in PA

The Pennsylvania Turnpike now has three full pavement reconstruction jobs underway. 38km (24mi) are being rebuilt at a contract cost of $127m. Another four segments totaling 64km (40mi) are in design and will start construction in 2001 and 2002 as the first three are complete. For the first time the Turnpike is breaking up all the original pavement laid down in 1938-1940. This is 230mm (9") of concrete with no special drainage course underneath. From the 1960s asphalt overlays were put on top of the concrete slab, and great efforts have been made to seal cracks and drill-&-grout to stabilize wobbly slabs.

The Turnpike is going to full depth asphalt for the rebuild, no less than 635mm (25") deep including a permeable asphalt base. The old pavement will be rubbelized to provide stone for the base. The roadway will be rebuilt in six asphalt layers. Cost is about $3m/km ($5m/mile) to do 2x2-lanes (780k/lane-km, $1.25m/lane-mi). In the process the turnpike is getting better shoulders, median and pitch. Some of the cost is in temporary reroutes of traffic to maintain all lanes in operation.