South Higuera road widening gets “crack and seat” process—something rarely seen on the Central Coast


December 19, 2017, San Luis Obispo, CA—In preparation for the Summer 2018 opening of the much-anticipated Octagon Barn Center, the County of San Luis Obispo has undertaken a roadway widening project along South Higuera. To properly widen and overlay on the existing El Camino Highway, a process called “crack and seat” was used to complete the project—a practice that is not commonly seen on roadway projects along the Central Coast.

The “crack and seat” process uses a large truck with a heavy spring arm drop hammer attached to a large truck to “crack” the pavement. The truck drives along the roadway dropping the hammer every three-to-five feet causing fractures in the existing pavement layer. A heavy roller is then used to “seat” the cracked concrete segments by compressing the fragments into the existing aggregate. Finally, a flexible overlay material is spread on top of the existing roadway to provide a base with greater longevity and reduced reflective cracking caused by horizontal and vertical movement—common culprits in roadway fracturing.

Widening of the roadway is expected to be complete by the end of 2017.