The purpose of the project is to test and document GPS controlled salt spreading on a test track by weighing distributed salt quantities and compare with intended amounts of salt at different spreading amounts, spreading widths, symmetries, speeds and types of salt (pre wetted salt and brine). The test is to study how salt distribution is affected by changes in the road section both to the right and to the left of the through lane or the two through lanes. Such changes should imitate for example transition from two lanes to one lane. In this project, we have chosen to study how close to the ideal salt spreading today's technology can get. Using pre wetted salt on two lanes and a bus-bay the results with GPS control got better, that means gave better correspondence with the intended amounts of salt, on the right lane compared with no change of the salt spreader. On the left lane the results were about the same. Both with and without GPS control small amounts of salt ended up on the bus-bay. Using brine on two lanes and a bus-bay the results on the right and left lane respectively were about the same with and without GPS. On the bus-bay the results with GPS got worse compared with no change of the salt spreader. Using pre wetted salt on a transition from two lanes to one the results with GPS control got worse on the right lane compared with no change of the salt spreader. On the left lane GPS control resulted in higher amounts of salt, but not better results, compared with without GPS. Using brine on a transition from two lanes to one at 40 and 65 km/hour the results with GPS control got better both on the right and the left lane. On the whole, spreading salt with GPS control gave about the same results as with no change of the salt spreader. On average the measured amounts of salt corresponded, in most cases, fairly well with the intended. GPS control of the salt spreader means that the quality of the salting can be improved because the salt, to a larger extent, is spread only where it is needed. GPS-control also has a positive effect on road safety and the working environment for the driver because he does not need to change the spreader adjustments but can concentrate on driving instead. (Author/publisher)
Samenvatting