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On almost every asphalt paving project, the crew spends the first part of the day or night setting up equipment. This set-up time can range from a few minutes to nearly an hour, depending on the condition of the equipment in the paving train and also the complexity of the application. Material conveyors or material transport vehicles, pavers, and compactors all need to be prepped for the hours of use to help ensure their uptime. However, it is not until the equipment is actually working that the crew is able to fine-tune operation of the paving train to produce the best quality pavement. Reading the mat or visually recognizing pavement defects in order to make equipment or process adjustments is one of the most important techniques for any crew to learn and master.

Complications
A finished pavement that earns full pay, plus all available incentives, is not easy to build. All variables in mix production must be carefully monitored to manufacture a homogenous blend of aggregates and fines (mineral fillers), plus asphalt cement and modifiers. Loading the mix into haul vehicles and its transport to the paving project should follow industry-recommended best practices; the hot mix asphalt (HMA) needs to arrive at the site hot to allow for proper laydown and compaction.

Preparing equipment for the HMA paving application requires attention to detail. Set-up of the paver is especially important, and can be particularly challenging. Most paver checks actually begin with visual inspection of the tractor to make certain of its readiness for safe operation. A complete walkaround should be done before the engine is started. Additionally, the screed must be examined and pre-adjusted for the application as proper screed set-up can actually save effort and time. This is typically done based on a crew's experience with similar applications, preferably before the screed pre-heating process is started.

It is only after "pulling off the joint" that the screed's set-up can be visually verified so the new pavement exactly matches a specified profile or the adjacent pavement surface. The operation needs to be tweaked often, even when the paver has been properly aligned and the screed has been set onto starting blocks positioned to compensate for anticipated roll-down of HMA during compaction.

The next challenge is to properly recharge the paver hopper with HMA. The truck driver needs to stop with the rear tires of the vehicle just ahead of the paver. Some paving crews assign a person to control positioning of the haul trucks or proper alignment in front of the paver and to keep trucks from bumping the paver. Even the smallest bump can create a depression behind and beneath the screed. These bumps can often be felt by traffic and may also be measured by a profilometer. Subsequent rolling may not fix this surface defect.