Cold In Place Recycling (CIPR) is a green and cost effective method to revitalizing the upper 1.5"- 4” of road surface; eliminating wheel ruts, cracking, and replacing both grade and slope if desired. This streamlined process involves grinding down existing pavement with a milling machine, which is connected to a mix paver where the material is then re-mixed with emulsion to be put back down in one pass. A recycled road is generally sealed or "topped" with another process such as Paver Placed Surface Treatment (PPST).
Typically, any road with sound structural strength and at least 3-5" of existing asphalt material, which suffers from wheel rutting, cracking, raveling, poor profiling or any other surface deficiency are good candidates for CIPR. Additional strength can be achieved by mixing cement or introducing new aggregates into the mix (add stone).
A road that has been recycled via CIPR has a re-gained smoothness due to the elimination of rutting, cracking, and poor profiling. The ride-ability of a recycled road is vastly improved as well as the structure and life expectancy. Coupled with an appropriate top course, a recycled road will outlast many alternative processes used by competitors. Completed CIPR projects can be expected to last upwards of 15 years before the need to revisit.
The photo on the right shows a comparison between two sections of State Route 695 in the State of Connecticut (both portions completed in 1997). The lower/left side of the image shows where a traditional mill and fill project ended and the upper/right side shows where Gorman's recycling project began. After 10 years there are significant cracking and profiling defects visible in the mill and fill portion but the recycled section shows no deficiencies.
In addition to solving numerous road defects, Cold In Place Recycling offers many environmental benefits as well. Since heating material is not required, air pollution and the use of fossil fuels are greatly reduced. Using existing materials also greatly decreases the need for additional asphalt cement and aggregates; energy savings peaking at 50% and cost savings near 40% make CIPR a very attractive process.