Work Zone Traffic Control Set up work zone traffic control according to the latest version of Penn Dot Publication 203. This publication is part of the Pennsylvania Motor Vehicle Code and constitutes minimum guidelines for safety. Select the correct signs and/or flaggers for your situation and place them as required. Cutting Cut out the hole in a shape that provides vertical sides and even edges for better support of the patch. Any polygon shape will do as long as the edges are straight and the corners form angles. Cut from the inside of the pothole out toward the marked lines. This prevents jamming of the cutting blade as the loose materials fall away as you cut.   Marking Mark the area to be patches. Markings tell the person cutting how much material to remove. Marking too far from the edge wastes material. Marking too close to the edge leaves deteriorated material at the edge of the path, inviting further failures. Marking a hand's breadth from the edge of the visibly deteriorated area is a good rule of thumb. Cleaning Remove all debris, damaged asphalt, dust, and water from the hole. Any loose materials that remain in the pothole will prevent the new material from sticking to the bottom of the patch. Asphalt and water don't mix, so dry out the hole as much as possible. Hot asphalt placed in a wet hole will cool rapidly, preventing proper compaction. Recent studies by SHRP (Strategic Highway Research Project) show that materials placed in a dry hole last two to three times longer. Tacking Apply a tack coat ( a sticky asphalt liquid) to the inside of the hole to help hold the patch firmly in place. PennDOT recommended E-6 and E-8 emulsions applied under Section 460 of Publication 408. The tack material will seal the joint that will form when the hot asphalt is placed next to the cold existing material. Compaction Compact the asphalt using a small roller or a vibratory plate compactor. Make sufficient passes to allow for a maximum compaction. Compaction must be done while hot mix is hot enough to allow the aggregate particles to densify properly. If the hot mix is too cold, proper density will not be reached. Make sure the area around the patch has been properly cleaned so your compaction equipment will not ride up on the excess material, preventing proper compaction. First, pinch the material into the hole by rolling the edges of the mix. Next, roll the center of the patch, moving outward toward the edges with each succeeding pass. This helps force the mix tightly against the edge of the old pavement. Filling Fill the hole with patching material. Hot mix ID2 is the best patching material for a long-lasting repair. However, when this is not available, cold patching materials will work adequately if placed according to these eight steps. When using hot mix, dump the patching material directly into the hole if possible. If you dump the hot mix on cold existing pavement, it will cool too rapidly. When the hot mix comes from the plant it is mixed at about 325 degrees. At this temperature the liquid asphalt in the mix is acting as a lubricant, allowing the aggregate to slip together easily under compaction equipment. As the hot mix cools, the asphalt stiffens and changes to a gluing agent, making proper compaction much more difficult. Spread out the material over the hole using a lute. Using a rake will cause the small pieces od asphalt-coated stones to separate and will further cool the mix. Clean-up Cleanup, while not essential to the performance of the patch, does contribute to the public's perception of how you do your job. The edges of the patch can be sealed, but this is an option as to the possible crack between old and new material has been sealed by the tack. If used, the edge sealer should be blotted with clean sand or screenings to prevent pickup by traffic. The excess material should be cleaned up and removed.

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