Top 10 Paving Don’ts
BY John Ball
In 2017, AsphaltPro magazine launched an online course that I consulted on to give paving crews training and education. It’s packed with the “paving do’s” for each member of the crew and for the crew as a team. Now let’s take a few pages in the magazine to review the Top 10 Paving Don’ts. These are some of the common mistakes crew members make, or common bad habits I’ve seen in the field, that you’ll want to eliminate from your routine so you consistently get a top quality pavement.
1. Don’t Try to Train Every Day
It’s just overwhelming to try to train crewmembers every day. Only train when the opportunity is good for you or you’ll hinder quality.
New workers will make mistakes. That’s okay. You know to watch out for mistakes and to help new laborers get up to speed while training on the job. But you don’t have the luxury of letting a new guy try to get compaction on the surface course of a highway project that’s got a time and smoothness penalty built into it. Let the new guy make mistakes—and help him fix the mistakes—on the binder course of a commercial project. The commercial project probably won’t hit you with thousand-dollar-an-hour deducts when you invest extra time going over an area to teach quality paving techniques to the newest member of the team. This is not to say a commercial project is any less important than an interstate project. Each one will represent your company’s work when you’re done, but one is less forgiving in terms of time and pay factors.
Next let’s look at some paving bad habits to break.
2. Don’t Ignore the Plant
You want to call the asphalt plant for updates, to monitor trucks and material delivery, and to stay on target for the day. Only by communicating with the plant manager will you know if the plant has broken down or stopped production for some reason. That affects your mix delivery, of course.
The plant manager also verifies what kind of mix you’re going to get at the job site. You want to ensure you’re getting the right mix design on your project.
When you talk to the plant operator, ask him for “around” 600 tons or 1,000 tons, instead of asking for an absolute. And ask for that rounded-off number by a certain time of the shift. The plant manager should be instructed to call you back when the plant gets near that production goal. This is another way to keep communication open. When you and the plant manager speak again, request the remaining tons you’ll need for the remaining part of the shift. You’ll know what that amount is if you’ve been keeping track of your trucks on the job, the tonnage delivered and your yield.
Speaking of the trucks, make sure each and every truck is using the same route. This saves drivers from getting lost and saves you from getting trucks—and their loads—out of order on the job. Remember, the mix they carry has an expiration date at some point during the shift; you want to get the material and get it placed in a timely manner.
3. Don’t Skimp on Start-up
It goes without saying that you’ll fill up fuel tanks and water tanks for the beginning of the shift. Interruptions in the paving day to refill the paver’s fuel tank or to refill the water in the rollers cost time and money. Make sure you know how much water the tanks hold. Also have a spare water tip in your toolkit. Then make sure you know how long you can run before the fuel will run out. You’ve got a gauge to look at, too. Watch it.
Another start-up practice you can’t afford to skip is lining out the job. If you don’t mark out your boundaries, you won’t be able to track your yield. You won’t know if you’re running over or under with material. That means you won’t know if you’re losing money on the job until it’s too late. You’ll get to the last truck of the day and realize you need two more loads, which can’t come until the plant starts back up tomorrow. That is a terrible waste of time and money that no small business can afford. To keep such a nightmare from happening to you, start the day with a good game plan that includes lining out the job and figuring how many tons each pass of the paver will require.
Mark that on the pavement and double-check how you’re doing as you go through the day.
4. Don’t Run Over a Co-Worker
You need a dump man on the paving job to ensure haul truck drivers bring mix to the paver properly. This person is on the ground and close to danger. If this is a new worker, make sure he is aware of the “no-go zone” in front of the paver. Never step between the paver and the haul truck. If someone needs to perform shoveling or scraping in between these two pieces of equipment, the haul truck must be stopped with the parking brake engaged, and a worker or spotter must be assigned to watch out for the safety of the team.
Watch for backing equipment in the work zone at all times. Be aware of the different backup alarms and beeping sounds. Don’t become so used to the sounds that you begin to ignore them. Let them always be a reminder to you that something big is headed your way. Look out for it.
Make sure backup cameras are clean and functioning properly to give added safety in the work zone.
Use a buddy system to keep each other safe out there. If you see your buddy in the path of a backing vehicle, you should be shouting and waving your arms to get the vehicle stopped and your buddy moving. Some companies give breakaway whistles to workers for use in such situations; some companies only distribute these whistles to the dump man for communicating with the haul truck drivers. Use anything you can to get a driver’s attention to stop a backover accident from taking the life of a co-worker.
5. Don’t Starve the Head of Material or Endgates
The paver operator will watch the flow of material from the hopper to the screed, and this goes through the auger box. The level of mix at the augers is referred to as the head of material, and you want it to be consistent and balanced across the width of the augers. Keeping it consistent means you don’t suddenly or radically speed up or slow down the paver.
The screed operator will watch out for changes in the head of material by setting and watching the feed sensors. These will be set for the height and speed of the particular job, and they need to be monitored to make sure nothing changes to mess up the mat. The feed sensors are typically affixed to the endgate. Make sure you direct them at an angle so they monitor the churning material correctly.
As a side note regarding the endgates: don’t let them get sloppy. You want to keep the endgates and their shoes (also called skis) clean and smooth. Maintain them and keep their springs lubricated for proper operation so they can be adjusted for proper downpressure. You want the ski to float along the joint smoothly, beautifully, without catching or tearing at the edge of the mat.
6. Don’t Put Lines, Marks or Footprints in the Mat
First and foremost, don’t let the new guy walk on the mat. Footprints don’t roll out. The roller’s drum bridges the footprint, leaving the foot’s impression uncompacted. It has never been okay to walk on the mat, whether that’s the base, binder or top course, but it’s especially important to train crewmembers to walk along the screed platform or to cross the mat after compaction.
Another mark to watch out for in the mat is a line that comes from an unbalanced screed. If you extend the screed without double-checking it, you could have an extension that is slightly higher—or slightly lower—than the main screed. This will cause a longitudinal line to form right down your lane as you pave. This line will represent the edge where a change in lift height begins and it will be impossible for the roller operator to resolve the problem.
Here’s how to correct lines in the mat: Check the extendible screed. Place a straight edge and a level on the screed plate, ensuring it overlaps the extension. Do you have the same percentage of slope in the main screed and the extension? Does the extension match up to the main screed perfectly? You want the answer to these questions to be “yes” or you want to adjust the extendible screed to make everything match nicely.
When rolling, the roller operator must be careful not to put his own lines in the mat. Be aware of the existing pavement edge to prevent the roller from riding up on the unforgiving surface, causing the drum to tilt and cut into the new mat. There are additional tips for the roller in our “Don’t No.7.”
7. Don’t Stop on the Hot Mat
Roller operators have the responsibility of being the last crewmembers to influence the quality of the mat. While a heavy, vibratory screed will get a majority of compaction—anywhere from 80 to 90 percent density—the breakdown roller is the all-important tool in achieving compaction behind the screed. This piece of equipment can also do the most damage due to its weight. You can’t let this machine stop on the hottest part of the mat because it will slowly but surely settle into the mat, forming two lines of more solid compaction where each drum has contact with the pavement. These lines will be next to impossible to roll out.
When rolling, the operator will need to slow to a stop for the purpose of changing direction. Here’s how to change direction without damaging the mat: Turn off vibration at least one roller length prior to stopping. Slow to a stop so that you don’t push and shove the mat beneath the drums. As you come to a slow stop, also slowly and gingerly turn the roller so that the end of the pass is curved toward the high side of the lane, rather than a straight line toward the paver. This curved indentation will be easier to roll out than a straight line of shoved mat. Then reverse direction and turn the vibration back on to complete the “back” half of the pass.
Don’t forget that you will roll in a straight line; don’t wander with the roller. You will curve at the end of the pass, but that is to achieve the diagonal stop and reverse.
There are a host of best practices for rolling in the two-part series “Roll for Bonus” published in the August and October 2017 issues of AsphaltPro. Read them online at www.TheAsphaltPro.com.
8. Don’t Speed the Process
Establish your paving speed and stick to it. Otherwise you’ll be running out of trucks, or you’ll be stacking your trucks. If you need to slow down because you called the plant and learned that there’s an interruption in delivery, adjust your paving speed slowly. Don’t suddenly go from paving 30 feet per minute to 10. Radical changes in speed cause the angle of attack to change, which creates waves in the mat. Waves cannot be rolled out and likely mean a penalty when it comes time for payment. Use automation and feed sensors to help you keep a consistent head of material no matter what.
9. Don’t Guess at the Temperature
The production temperature of the mix was set by a mix designer or state materials specifier for a reason. Depending on ambient conditions and haul distances, you might receive the mix at a temperature that is less than ideal. The foreman on the job has the right to refuse a load of mix if it doesn’t meet temperature specs.
When the haul truck arrives on site, measure the temperature of the mix. Double-check the temperature at arrival and at the screed. The dump man, screed operator and back roller operator really must have a temperature gun to monitor the perishable product you work with. When the finish roller operator sees that the mat has cooled to 175 degrees F, he knows he can get the finishing touches of compaction and smoothness. But when the mat has cooled to 140 degrees or lower, he needs to stop rolling. Additional attempts at compaction when the temperature is below 140 degrees F could damage the mat rather than improving it.
Everything on the paving train relies on time and temperature. Having a way to monitor actual temperatures is a must.
10. Don’t Leave the Job Without Walking the Job
We could also call this step: “Don’t leave a mess.” The job should not be considered complete until the foreman or supervisor has inspected it, decided it is good enough to bill the customer, and then sent the crewmembers back to the garage. You don’t want any call backs to Job A when you’ve moved to Job B or Job C next week. You don’t want to come back for repairs or restriping because it could cost your company thousands of dollars in equipment moves, fuel, material, labor, lost time on another job, and the list goes on.
Instead, the foreman—and any other crewmember he wishes to accompany him—should walk along the curbs of the parking lot project. He should examine the adjoining landscaping of a commercial property project. Or he should drive along the shoulder or mainline of a highway project. You’re looking for imperfections, rough spots, overspray, missed striping, forgotten equipment attachments in the tall grass, and the like.
Make sure each crewmember has picked up his trash as well as his equipment and tools. If you see an area that could turn into a birdbath during tomorrow’s rain, fix it now. If you see a shovelful of mix alongside a storm drain, send a laborer with a shovel and bucket to clean it up. If you see splashed sealant marring a concrete car-stop, get a laborer to paint the car-stop back to its clean and pretty state. By ensuring all details are right, you present a top quality job to the consumer and client. The project that looks good makes your company and your industry look good.
As your crew grows together, you will notice little mistakes here and there that you can help each other learn from. When I go to a paving site to consult and train, I like to videotape the crew for a few minutes so I can show them where they’re using best practices and where they have room for improvement. If you see a co-worker doing something that will harm the mat or screw up quality, show him a better way. If you see a co-worker putting himself or others in danger, make sure you stop him and get safe practices in play. A list of “don’ts” isn’t meant to embarrass or punish anyone; it’s meant to remind us that we all have habits or methods we may have learned that need refining. Work together as a team to fine-tune and fix the elements of paving for a top quality job every day.
John Ball is the proprietor of Top Quality Paving and Training, Manchester, New Hampshire. He provides personal, on-site paving consulting services around the United States and into Canada. For more information, contact him at (603) 493-1458 or firstname.lastname@example.org.