Petrotac Being Rolled Out on Bridge Deck

Interstate 70 in Greenfield, IN Renovation

The Problem:

Interstate 70 running East and West is one of the most traveled interstate highways in the United States. Due to a major increase in population, the eastern metro Indianapolis area had taken its toll on Interstate 70 running through Greenfield, IN.

The current composite pavement had an underlying Portland Cement Concrete (PCC) pavement with five inches of asphalt concrete on top. The asphalt had seriously deteriorated caused by surface water infiltration that weakened the pavement foundation layers and led to erosion and freeze and thaw damage. In order to renovate the roadway, all asphalt was milled to the old PCC surface so it could be replaced.

The Solution

In order to ensure the renovation would offer long-term benefits, INDOT needed a solution that would diminish cracking from the PCC pavement that could reflect up into the new overlay. The badly damaged PCC joints were patched up and the moderately stable joints were covered up with strips of PETROTAC® to increase the life of the replaced overlay. PETROTAC® is a self-adhering paving membrane interlayer designed to obstruct reflective cracking through stress absorption.

Running along a stretch of 7.5 miles, the existing joints and other cracks were filled, a primer was applied directly to the milled surface and PETROTAC® strips were applied over certain joints and cracks on the PCC pavement.

Bridge Deck Renovation work

Paving Fabric Used for Indiana Highway Project

Performance

There were a number of less active and spalled joints, along with cracks, that remained in place. PETROTAC® Enviro was included in the design to offer a full pavement moisture barrier and stress absorption interlayer. INDOT had used PETROTAC® Enviro once before on a section of Interstate 65. Everyone was pleased with its ability to increase the life of the pavement. INDOT liked the paving fabric's capability to be milled and recycled.

A 0.26 gallon/square yard of PG64-22, was sprayed onto the milled pavement and over the PETROTAC® strips. Afterward, Enviro was applied and then the intermediate HMA course was placed. Enviro is perfect for installation over milled surfaces because it offers good elongation to conform to the rough surface. Lastly, the wearing surface course of asphalt cement was placed in order to complete the renovation.

The thought behind using  PETROTAC® over the really bad joints and cracks were followed by a full-width installation of  PETROTAC® Enviro which gave the pavement everything it needed to extend the life of the replacement overlay.  Also, the pavement foundation layers would regain strength, erosion would stop, and would avoid freeze and thaw damage.