By Geoff Dillon

In an asphalt pavement, longitudinal joints occur where one paving lane (also called a “mat”) is placed adjacent to an earlier placed paving lane. The localized area of the longitudinal joint is more difficult to compact and, as a result, has higher in-place air voids compared to the interior of the mat. While in-place void levels at the interior of the mat are typically 6-8 percent (92-94 percent compaction), void levels at the joint can be 10 percent or greater. 

By James Gallegos, P.E. and Dave Johnson, P.E.

Based on positive responses from past events, a third International and Western States In-Place Recycling Conference was held in conjunction with the Rocky Mountain Asphalt User/Producer Group’s Annual Meeting in the fall of 2018.

One of the presentations at this event was made by James Gallegos, New Mexico Department of Transportation (NMDOT) Materials Engineer, on a cold in-place recycling (referred to as cold in-situ recycling in New Mexico) project on U.S. Highway 285 in southeast New Mexico. This project is an example of the information from those past conferences reaching the project level.