Training keeps compactor crew sharp
By Jeff Winke
The most elemental meaning of the word “compaction,” is the exertion of force on something so that it becomes more dense.
In the realm of road construction, compaction is considered one of the most important processes in pavement surface construction. It is necessary in order to attain high-quality and uniformity of pavement materials, which in turn better ensures the long-lasting performance of the paved surface.
It has been more than a few years since the term and method of “intelligent compaction” (IC) has become a given in discussions of roadway paving. Today, it has become the norm — compaction is pretty much considered intelligent compaction.
Yet, no matter how “intelligent” and technologically sophisticated the machine has become, the crucial performance results are still the responsibility of the compactor operator. The paving project success and the pavement’s long-term performance can rest in the skills of the compaction machine operator.
“Roller compactor operators need to understand their primary function in the paving process, since asphalt compaction is the final step in laying down quality pavement,” Eric Booth, product training/marketing manager, Sakai America, Inc., Adairsville, Georgia. “They need to be observant in order to monitor their roller … looking at asphalt temperature, how much water is in the tank, is the DEF (diesel exhaust fluid) tank full, what is the status of the DPF (diesel particulate filter), is any asphalt picking up on the drums, etc. The plant, milling machine and paver can do everything correct, but if the roller isn’t on the mat at the right time or is ignoring general maintenance, this can cause density issues that lead to early failures and potentially impact any guarantees the contractor may have made about the performance of the work being completed.”
Clearly the machine operator needs to know what they are doing during their walk-around inspection and when seated in the operator’s compartment operating the machine.
“While operating a roller might seem rather basic, as it consists mostly of going back and forth preferably in a certain pattern, it is absolutely important that the operator not only knows about the different functions of the equipment, but first and foremost knows how to stop the unit and where the emergency stop button is located,” stated Bert Erdmann, product manager-compaction for BOMAG America, Ridgeway, South Carolina. “Once the safety aspects have been covered, including instructing the operator to stay safe and alert at all times, and to stay far enough behind the paver, the compaction machine needs to operate at an adequate and safe distance from the asphalt paver to prevent common accidental ‘run ins’ with the paver screed!
“Rolling patterns can be established next, and covering the importance of the use of water on the steel drums to keep them from picking up asphalt. It would also be beneficial for the operator to have a basic understanding of asphalt temperature, to recognize the somewhat ‘narrow timeframe’ during which the material can still be compacted with vibratory drums, and when vibration should no longer be used to prevent ‘over compaction,’ when crushing the asphalt aggregate can occur.”
Operator performance has become more and more critical to the bottom-line success of paving jobs. The operator needs to adapt to different jobsite conditions by using all of the features offered on an asphalt roller.
The operator is just as important as the machine. A contractor can have the best machine in the world, but if the operator is not running it at the right settings and the right speed, it can affect the quality of the mat, and the all-important life of the road.
“Most roller manufacturers, in conjunction with their dealers, offer training for end-users of their equipment,” Erdmann said. “That training is available in a variety of forms, including group seminars, hands-on courses or one-on-one training on the jobsite or at the manufacturer’s training grounds.
“Often it is beneficial to an operator to understand why, for example, certain rolling patterns are being established, what the benefits are, or the possible disadvantages or potential problems rather than just ‘doing as one is told.’ Knowing when to slow down or how to read the machine’s technology outputs can take the guess work out and ensure the job is optimized for time, and to corroborate, verify, and document job results.”
Operator training helps to minimize some of the most common mistakes when operating a compaction roller…mistakes that can result in corrugated or “washboard” roads with dips, divots and indentations that compromise mat quality and road life.
Training can also equip operators with the knowledge to overcome hurdles that can crop up on a project, such as difficult weather conditions, clumpy mixes, extremely thick or thin lifts, or how best to join hot and cold lanes. The ability for an operator to successfully adapt their rolling pattern to successfully compact the ever-increasing variety of mix designs is arguably the greatest training challenge that must be met in order to maintain quality and productivity the market demands.
Compaction is critical to an asphalt paving project. “For the contractor on any paving job, meeting the budget and securing bonus money is most important,” Booth said. “So, for the compaction crew, that means ensuring target density over the entire mat, including joints and edges. Pavement smoothness and rolling pattern efficiency are primary performance expectations for compaction.”
Booth continued: “Encourage the operator that the roller is their office space, and make sure they take pride in the appearance of their office. Make sure they understand machine settings for different applications and occasionally quiz them on what each button or switch does. In many regions, paving is limited to warm month activity, so a refresher on roller features and operation is helpful before the new season starts up again.”
Certainly, the key benefit of a well-trained, skilled compaction machine operator is greater control over the compaction results, which in turn provides better finished paved results. Compaction at its most elemental is the exertion of force on something so that it becomes more dense, while the compactor operator ensures that compaction is performed consistently, thoroughly, and accurately.
Jeff Winke is a business and construction writer based in Milwaukee, Wisconsin. He can be reached through firstname.lastname@example.org