Avoiding Sinkholes in Florida
Nov 12, 2013
The Florida Geologic Survey categorizes Madison County as a region where "abruptly-forming collapse sinkholes dominate". During a recent job on Interstate 10, Anderson Columbia could not use rollers in vibratory mode due to the possibility of sinkholes in the area. To produce a high-quality road with good compaction density, Anderson Columbia used Evotherm to produce the 12.5mm surface mix. The mix contained 5.0% 76-22 polymer modified asphalt with 0.5% Evotherm provided by Ergon Asphalt & Emulsions. Production for the 25,000 ton job started at temperatures of 320⁰F to warm up the equipment and was quickly dropped to 280⁰F for the remainder of the day. The haul distance from plant to job site was 63 miles, taking the trucks a little over an hour to reach the job and causing the mix to lose only around 5⁰F during the haul.
Placement consisted of a 2” mill and fill on both east and westbound lanes of traffic. Anderson used aRoadtec MTV and CAT AP1000D paver to place the mix. For compaction they used 2 CAT CB54rollers in tandem to breakdown and another CAT roller to finish. Even though the rollers were resticted to static mode, core results from the first round of cores taken measured 92.01%, 92.8%, and 93.6%.
Author: Ryan Bragg