Cold In-Place Technology used in Full-Depth Reclamations

E.J. Breneman believes in pavement preservation. One new process the company is trying is Full-Depth Reclamations using Cold In-Place asphalt equipment and technologies.

This process, says the company, can address an entire pavement section - correcting delinquent cross sections, increasing the load-bearing strength of the base material, and utilizing 100% of the existing materials at the required depth.

Following are four municipalities which have successfully used this method for limited depth Full Depth Reclamation (FDR) projects.

Limerick Township

Limerick Township used the process in an industrial park that had been scheduled for Cold In-Place Asphalt Recycling. The park was relatively new; it was curbed with a few sanitary sewer manholes and catch basins.

The industrial park was growing in size, and the increased construction activity was coursing premature failure. The industrial park had an asphalt depth of four inches on top of a thin aggregate base. There where signs of some isolated soft areas and the municipality new some other areas may become evident after the CIR process had concluded.

Unfortunately shortly after starting the CIR process the pavement under compaction became wavy and distorted. It was determined that CIR could not correct the pavement problems and that FDR Portland cement was the alternative. To move all the CIR equipment out and haul the FDR equipment in was going to be a huge mobilization cost.

It was decided by both the municipality and the contractor that they would try to Portland cement stabilize the base using the CIR equipment.

The weight of the mill did not seem to disrupt the pavement during the earlier process (CIR); it seemed to happen only when under compaction with vibratory compactors and large pneumatic rollers.

The CIR equipment train had no difficulty in cutting the eight inches or mixing the Portland cement into the milled material. The mixed Portland cement was totally hydrated, one reason for this, the material stays in the cutting head for a long period of time and is continuously rotated and mixed around the drum unlike a reclaimer that mixes the material once and expels it into the cut.

A truck-mounted cement spreader laid the Portland cement at 35 pounds per square yard. A mix design was not completed on this project because of the late time of year and the necessity to complete the project so as an asphalt overlay could be applied while temperatures stayed reasonable. We recommend a mix design is formulated before any type of CIR or FDR project commences.

The project in Limerick was successful no failures have occurred and the park has grown over the past four years. The equivalent to 19mm Super Pave hot mix asphalt was applied on top of the FDR at a depth of 2.5 inches.

Delaware DOT

In 2008, the Delaware Department of Transportation in Sussex County had been Cold In-Place Asphalt Recycling several roadways under contract to George & Lynch Inc. of Dover, DE.

During the construction of SR 20 near Dagsboro, DE the department had an adjacent roadway that was scheduled to be Full Depth Reclaimed under contract to E.J. Breneman.

Since this FDR project was so far south and also because the CIR equipment was basically on-site and no mobilization would be required, the department under took their own experiment using the CIR equipment to FDR Portland cement stabilize the roadway.

The depth once again was eight inches using around 40 pounds of Portland cement. Wilguse Cemetery Road runs between SR 20 and 54A.

Wilgus Cemetery is a two-lane rural roadway with residential and agricultural traffic and is used as a short cut between the two state roadways. The roadway has several layers of oil and chip on top of a small layer of hot mix asphalt. The sub-base was primary sand and gravel material.