Chip Sealing over Fabric in Borrego Springs, California

摘要

This paper will discuss the County of San Diego's practice of placing pavement reinforcing fabric, followed by chip sealing and fog sealing, on roads located in the county's desert area of Borrego Springs, California. Due to extreme desert temperature variations and exposure to flash floods, surface cracks on the asphalt road surface are a routine occurrence, and crack sealing is a constant road maintenance issue. The cost to seal the numerous surface cracks reduces the funds needed to apply a surface treatment to the entire road surface. In 1987, the county conducted a study of placing various surface treatments on desert roads to determine which address surface cracks and also seal the entire road surface. It was found that placing pavement reinforcing fabric, immediately prior to placing a chip seal, prevented surface cracks from reflecting through the new road surface treatment, and prevented moisture from penetrating into the pavement and underlying base. It was also discovered that considerable savings were experienced by not having to crack seal before or after the placement of the pavement reinforcing fabric. This paper will address the placement of pavement reinforcing fabric, in conjunction with chip sealing and fog sealing, via contracts awarded to private construction firms on a competitive bid basis. Life-cycle cost analysis will also be addressed.