Better Roads Digital Magazine
Issue link: http://read.dmtmag.com/i/165348
Photo courtesy of Tom Kuennen RoadScience Roadtec's material transfer vehicle (MTV) revolutionized asphalt pavement quality control by reducing aggregate and thermal segregation in mixes, as well as isolating trucks from the paver hopper. For the contractor, compaction to spec means 100-percent payment, but it also means the contractor will have accomplished the final requirement that was specified when the project was designed for the pavement's loading and daily traffic count. For the public sector client, QC of compaction is important because it proves the pavement meets the criteria set forth in the specifications and that the pavement will perform the way it was intended, including meeting lifecycle cost requirements. The road users benefit, as well. Quality compaction depends on good-quality material com- ing from the plant. Crews should discuss the day's paving each day before the work starts. Crews that function as a team, and not individuals, will consistently achieve quality compaction. QC also will consider delivery of the mix to the jobsite. Undesirable segregation of aggregate within the mix takes place during the haul: The longer the haul, the more the segregation. It also is encouraged by too-fast dumping of asphalt in the paver hopper, so drivers need to dump slowly. Hopefully, the truck will never touch the paver; the resulting bump will cause a discontinuity in the mat, impacting smoothness. Even as your supplier or staff has verified asphalt content, aggregate content and gradation and temperature of the mix as part of their QA program as it leaves the plant, the mix will contain too much air to support loads. Compaction lowers the total volume of the mix by forcing air from the THAT INTEGRATES WITH YOUR ACCOUNTING SYSTEM. mix and reducing air voids. The degree of compaction generally is measured as a percent of dense asphalt minus the remaining air voids. Roller speed, the number of passes, roller pattern, mat temperature and ambient environmental conditions all impact compaction. Test strips are an important part of QC, as they help manage these factors, establishing the roller pattern and optimum Estimating Dispatching Safety GPS Mobile number of passes necessary to provide a Apps Job Costing Equipment Fuel Tracking Cloud smooth, well-compacted mat that will last Maintenance Hosting during the lifetime of its usage. One QC measure demanded by many Used by 40,000 construction professionals road agencies for high-level pavements World-class 24/7 instant customer support is the use of a material transfer vehicle Construction-friendly desktop & mobile apps (MTV), which allows the paver to move Innovative Proven processes for implementation Software without interruption, eliminating trucks Low risk—Software comes with a for the Construction Industry bumping the front of the paver. The MTV 12-month money back guarantee! also mixes asphalt from the truck before 800-683-3196 it enters the paver, ensuring a mat with SIGN UP FOR DAILY WEBINARS consistent material temperature with at www.HCSS.com/Better-Roads minimal aggregate segregation. INDUSTRY LEADING CONSTRUCTION SOFTWARE Text INFO to 205-289-3789 or visit www.betterroads.com/info 6 September 2013 Better Roads RoadScience_BR0913.indd 6 8/30/13 8:20 AM