Waidley, Greg

MnDOT evaluated five pieces of new winter maintenance equipment: two slurry spreaders, an underbody scraper, a true-float wing plow and a two-way reversible plow. For Winter 1 of the evaluation program, all equipment was acquired, installed, and field-tested in MnDOT District 2. For Winter 2, a data collection program was developed to capture quantitative data on how well the equipment worked in District 2, compared side by side against comparable routes with traditional spreaders. Winter 1 and 2 field testing of the three types of plow equipment allowed operators to fix operational problems and led participants to agree that MnDOT should continue to use such equipment and acquire more. MnDOT participants did not reach consensus on whether to continue to use or buy more of the two slurry spreaders. Data analysis showed that they performed comparably to traditional slurry spreaders in terms of road regain time and salt use when they were operational. Issues included equipment height, causing loading and maintenance worker safety concerns; equipment weight, reducing how much material could be loaded in the truck; difficulty in setup; equipment not operating as expected; and difficulty obtaining vendor parts and getting vendor support. These issues led to the cancellation of a third winter of testing in a different district. It was suggested that the equipment might better suit MnDOT’s needs by mounting it on a boxless truck.

As an alternative for snow and ice control; potassium acetate (KAc) has potential advantages compared with salt and brine--reduction of chlorides entering receiving waters; a lower effective deicing temperature; and reduction in corrosion impacts--but success in the field has been largely anecdotal. MnDOT District 1 worked with an investigator team to test KAc applied on four plow routes in the Duluth; Minnesota; area over the 2018-2019 winter season. Field trials protocols and data collection methods and forms were established to capture the following data during winter storms: vehicles and routes; material used; application rates; frequency; and timing; weather conditions; and pavement conditions. Due to issues beyond the control of MnDOT or the research team involving process gaps and data availability; a quantitative assessment of KAc could not be completed for this study. However; interviews with field crews yielded a wealth of useful observations and practical recommendations in the areas of training; liquid and sand concentrations; vehicles and equipment; snow removal procedures; application rates; and environmental concerns. The investigators also developed process recommendations for improving the chances of success for similar types of research studies in the future..