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Pavement recycling is a necessity due to the diminishing supply of available construction materials and increasing regulations concerning the disposal of removed concrete and asphalt pavements. Since the 1950's and 60's recycling has grown to include hot and cold mix asphalt recycling, the use of crushed asphalt pavement as an aggregate base, and the use of Portland Cement concrete as an aggregate base, concrete aggregate, and bituminous aggregate. Crack and seating and rubblizing of concrete pavement are also common forms of recycling in Minnesota. The Minnesota Local Road Research Board (LRRB) requested that a report be written to provide information regarding the common methods of recycling, and to determine the status of recycling in Minnesota. This report outlines the recycling methods listed above, and gives specifications and mix designs for their use in Minnesota.

Each year miles of utility trenches are cut, backfilled, and surfaced by utility companies, government agencies, and contractors. Improper repair of these trenches leads to bumps, settlements and pavement failure. Unfortunately, city and county governments are not always responsible for the repair and have little control over the construction methods used. To provide information regarding the methods of repairing utility trenches that are commonly used in Minnesota, the Local Road Research Board (LRRB) requested that this report be written The report outlines the results of a survey of Minnesota cities who were asked to detail their specifications and construction methods for backfill and surface repair.

Accelerated soil erosion and the sedimentation caused by it pose serious problems for the construction industry and state and local agencies. Runoff from construction sites has high sediment loads which may contain various pollutants, including oil, chemicals, and soil wastes. Natural erosion in ditches and along roadways may result in sedimentation that may result in costly damage to water and land. Drainage channels, culverts, and storm sewers may be filled and plugged by sediment, resulting in frequent and costly maintenance. This report addresses those problems and outlines methods for controlling erosion both during and after construction. Structural and vegetative practices for reducing sedimentation are given, and turf establishment techniques for native grasses and wildflowers are discussed. Information regarding the National Pollution Discharge Elimination System (NPDES) Storm Water Permit Requirements is also given.

The purpose of this handbook is to provide background information about the importance of pavement preservation and preventive maintenance, as well as present maintenance techniques for a variety of distresses and conditions. The major focus of this handbook is on preventive maintenance activities, which are performed while the roadway is still in good condition with only minimal distress, before the pavement falls into a condition where structural overlays, major milling or reclaiming, or replacement is necessary. The most common flexible pavement distresses are cracking, roughness, weathering, raveling, rutting and bleeding. If the distresses identified in a pavement are related to structural deficiencies, the pavement section is most likely not a candidate for preventive maintenance treatment, and should be scheduled for rehabilitation or reconstruction. Maintenance treatments covered in this handbook include: crack repair w/sealing, including clean and seal, saw and seal, and rout and seal; crack filling, full depth crack repair, fog seal, seal coat, double chip seal, slurry seal, microsurfacing, thin hot mix overlays, and potholes and pavement patching. Tables are outlined giving the most common flexible pavement distresses, along with the best practices for rehabilitation for each. Also given are recommended applications for crack sealers and fillers, surface treatments, and pothole patching. Specifications, technical memoranda and special provisions are included for all treatment methods recommended in the handbook.

This report documents substantial work for MnROAD Phase II Construction, which began in 2007 and continued in 2008. Funding sources for the construction and research have come from many partners both locally and nationally. New test cells consisted of both new construction and rehabilitation techniques representing both national and regional interests. Funding for this phase of MnROAD is $10.9 million, which covers construction, research, instrumentation, and administration costs. The core research areas that guided Phase II Construction are mechanistic design, innovative construction, preventive maintenance, recycled materials, pavement rehabilitation, surface characteristics, and other nonpavement research. The purpose of this report is to provide details on the MnROAD construction that was completed during the 2008 construction season. It features projects that involved the reconstruction of Cells 2, 3, 4, 5, 6, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, and 23 on MnROAD's Mainline section and Cells 24, 39, 53, 85, 86, 87, 88, and 89 on MnROAD's Low Volume Road section. The new test cells included various asphalt and concrete pavement materials as well as various aggregate base materials. This report documents the research projects and objectives, pavement structural and mix designs for each cell, instrumentation plan, field construction activities, material sampling, and laboratory test results.