training
Train Proper Straight Edge Use for Bonus Quality Paving T
This article will talk about the proper use of the metal straight edge for good quality control during paving, but we have some extra tips to point out along the way. Let’s start with the reason for having a straight edge out on the paving job. The untrained or new laborer might not understand why the crew has an 8-footlong, 11- or 14-gauge, 2 by 4 steel tube on the deck of the paver or in the back of the work truck. This vital tool will help all the laborers—from the new guy with the rake to the foreman trying to figure yield. It helps you keep track of slope, high and low spots, crown, and proper takeoff depth in the mat. You’ll use the straight edge to check joints, match height and any number of quality control/quality assurance (QC/QA) factors that affect your pay. Before you even begin the paving day, here are some steps we need to do first. • Step #1 null out tow point cylinders while the screed is on the ground. • Step #2 with another worker, null out the depth cranks on each side of the screed. • Step #3 on each side of the paver, make the endgates level with the screed. With those steps done, you’ll raise the screed and place the straight edge against its underside to double-check the smoothness of the screed plate. For this quality check, make sure the slope extensions are not engaged. You’ll place the straight edge against the trailing edge of the screed for this check. A sixteenth of an inch of crown in the screed is acceptable/normal. Anything more than that is a problem. These back-to-basics steps are spelled out in detail in the online training course at https://training.theasphaltpro.com/.
Back in the old days, when screed plates were 36 inches wide, we had the lead crown and tail crown to consider. Don’t worry about multiple readings now that the typical screed plate is only 18 inches.
10 // May 2021
CONTROLS
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CONTROLS
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In this picture, the crew places the straight edge transversely across the mat behindCONTROLS the screed to double-check the crown in the mat.
INSPECT SERVIC
CONTROLS
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CONTROLS
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The orange arrow points to the area where beginning-of-load segregation showed up in this binder course. You can minimize this if you avoid running the hopper empty between trucks.
