Mix repairs interstate in high-volume traffic

June 26, 2017

Pennsylvania Department of Transportation (PennDOT) District 1 is responsible for over 3,600 road miles and more than 2,000 bridges. Thanks to severe winter weather and lake effect snow conditions, this region is perhaps the most challenging area for maintenance of all the PennDOT districts. The District 1 region includes Crawford, Erie, Forest, Mercer, Venango and Warren counties.

Unique Paving Materials Corp. (UPM) and Tom Mello, assistant maintenance manager for PennDOT, Maintenance District 1 scheduled a product demo on January 25, 2017, in Erie County on I-90 westbound, about ½ mile west of the intersection of interstates I-79 and I-90.

The pavement is a concrete base with an asphalt overlay, and the shoulders are concrete. With the large amounts of brine and salt used to maintain this very icy and snowy region, the surface pavement is very porous.

The district has many re-repair issues from using poor-performing locally available “high performance” cold mixes.

The center seam area of the driving lane seemed to suffer from the most potholes. The asphalt area next to the concrete shoulder seemed to be undergoing major fatigue and was losing its bond to the concrete shoulder. Many repairs have been made to this section with the locally available mixes; most fail within a day.

The district crew followed the necessary requirements to properly prepare the area that would be repaired. This included blowing out standing water, cleaning the hole and chipping out any loose asphalt in the holes when necessary.

The first phase of the demo was the travel lane on I-90 west, about ½ mile east of mile marker 190. Both the lane and the shoulder were repaired. The crew then switched to the passing lane and repaired it. The crew was impressed with the black/shiny appearance of the UPM cold mix, the ease of placement and the ability of the material to almost “self-level” after it is put in the hole.

After the crew compacted the patch areas, they noticed there was no delamination of any of the material. Even when trucks and cars went over the patch, the UPM patch material was not kicked up. One of the team members, Paul Parkhurst, who was also one of the union leaders, said that he appreciates how this product offers a level of safety that others do not. The less they have to do re-repairs at the same patch area, the safer his crew members and other laborers will be, since they will be less exposed to traffic and the elements.

Follow-up pictures by PennDOT District 1 show the UPM mix is performing well on I-90. The UPM mix is holding well after five months, even with the daily heavy vehicle traffic.