MWV Asphalt Innovations and Charleston County are collaboating to improve the method and materials used to pave low-volume dirt roads in South Carolina and the Southeast. These efforts resulted in a reduction of construction costs from an estimated $1.1 million to approximately $350,000 for the Joseph White Road project.
Rural roads present many challenges to counties across the country. These low-volume roads are commonly one to two lanes wide with natural, gravel or other surfacing and may have been constructed to relatively low standards with a limited budget while forming the transportation backbone of many communities. Matthew Fountain is the Engineering Manager with Charleston County Public Works. “We need to pave these roads because the regular maintenance is overwhelming...Not to mention the expense. We need something that is economical, constructible, and sustainable.”
Sanders Brothers Construction started with the SCDOT standard open graded friction course (OGFC) mix designed for interstate traffice. They first adjusted the aggregate gradation to accomodate locally sourced material. The lower traffic load requirements allowed for the use of a PG64-22 binder supplied by Associated Asphalt instead of polymer modified asphalt. The addition of Evotherm warm mix asphalt technology allowed the removal of expensive fibers and lime while maintaining drawdown standards and adhesion properties. The resulting Charleston County mix was engineered to perform as a 2” lift as the final surface course.
Stormwater management is critical in the southeast where flooding rainstorms are a part of summertime. Transitioning a dirt road to a pervious pavement improves the road surface for residents while eliminating the need for drainage ditches and their associated easement issues (no digging up someone's front yard). In a few short hours, the residents of Adams Run residents and commuters of Joseph White Road saw it transformed from a dusty road to a freshly paved street that was ready to use.
An added bonus is how well the road handles the summer rain - much better than the old dirt road!
Author: Dean Frailey