612Milling

612.1 Description

Remove the existing surface to the depth and limits shown in the Contract Documents or established by the Engineer. Load and stockpile the milled material, when required. Provide transitions at transverse joints and raised st ructures to create a smooth longitudinal riding surface before opening the milled surface to traffic. Remove transitions prior to resurfacing. B I D I T E M U N I T S Milling * * Unit of Measurement Shown in the Contract Documents

612.2 MATERIALS – None specified.

612.3 Construction Requirements

Remove the existing surface to the required grade line as established by the Engineer. Use equipment that is automatically controlled with regard to grade and slope. Operate the automatic grade and slope control from a traveling stringline, a minimum of 30 f eet long, attached to the milling machine and operating parallel to the line of travel. Extend the cross slope of the pavement by milling across the shoulder to the point where this line intersects the existing shoulder surface or to the edge of the s houlder, whichever is less, unless shown otherwise in the Contract Documents or directed by the Engineer. When sh oulders are to be milled (daylighted out), mill them the same day as the adjacent traveled way pavement is milled. When milling multiple passes, mill so the longitudinal joint between passes is flush. When milling asphalt down to an existing concrete pavement, keep the final milling operation a maximum of 2 miles ahead of the laydown operation, unless approved otherwise by the Engineer. Do not track the milling machine across span bridges if the operatin g weight of the machine exceeds 80,000 pounds. Limit the operating weight of the milling machine to 80,000 pounds when removing existing asphalt material from, or performing machine preparation on a bridge deck. If the milled area will be opened to traffic prior to resurfacing, perform the following:  At transverse joints, either feather transitions between milled and unmilled surfaces by milling or placing a wedge of hot mix asphalt (n o steeper than 1 vertical, 24 horizontal), for the entire width of the transverse joint.  After removal of existing material around manholes , utility valves inlets and other appurtenances, place a temporary wedge around the appurtenance (no steeper than 1 vertical, 12 horizontal).  Use hot mix asphalt or other approved material of a thickness and design that the material remains intact while under traffic.  Remove transitions prior to resurfacing. Do not open the milled area to traf fic unless all transverse joints, manhol es, utility valves, inlets and other appurtenances have wedges in place to provide for a smooth longitudinal riding surface.

612.4 Measurement and Payment

When milling is a bid item in the contract, the Engineer will measure milling as shown in the Contract Documents. This shall include the removal, hauling, if required, and stockpiling of existing surface. When shown by the Station, the Engineer will measure the Station along the centerline of the lanes, regardless of the pavement width. When shown by the square yard, the Engineer will measure the square yards of surface milled. When shown by the ton, the Engineer will measure the tons of material milled. Payment for "Milling" at the contract unit pri ce is full compensation for the specified work.

Milling in other states

• Indiana 306 · MILLING
• Vermont 210 · MILLING