Browsing by Author "Lukanen, Erland"

Now showing 1 - 3 of 3
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    Cost/Benefit Study of Spring Load Restrictions
    (2005-03-01) Levinson, David M; Marasteanu, Mihai O; Voller, Vaughan; Margineau, Ioana; Smalkowski, Brian; Hashami, Maryam; Li, Ning; Corbett, Mike; Lukanen, Erland
    Across the state of Minnesota, asphalt roads under the jurisdiction of counties, cities and townships have been controlled by restrictions that limit the total weight of each truck that uses those roads during the spring thaw period. During this time, the pavement weakens and the bearing capacity of the roadway is reduced. These policies vary from county to county and from road to road, depending on the capacity of the roads--typically, 5, 7 and 9 tons. While spring load restrictions serve to extend the useful life of the road, they also add significant burdens to truckers who are forced to re-route their vehicles and/or increase the number of trips in order to adhere to the policies. This study assesses the economic impact of lifting all vehicle restrictions during the spring thaw period. Economic benefits of lifting the bans include reduced cost to carriers; potential cost includes reduced pavement life. Their research concludes that if the policy is changed, the costs of additional damage could be recovered from those who use the roads. Recovering those costs could take the form of annual fees, appropriate fuel taxes and/or user charges paid by vehicle operators.
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    Load Testing of Instrumented Pavement Sections
    (2005-11-01) Lukanen, Erland
    This report summarizes and references seven previously written reports developed from this project. The objective of this project was to use the field-measured strains from a number of MnROAD cells to develop mechanistically based load equivalency factors (LEF). The load equivalency factors commonly in use were developed from the AASHTO Road Test conducted in the late 1950s at Ottawa, Illinois. The AASHTO-based LEF represented the pavement behavior at the Road Test and might not reflect conditions in other climates, other subgrade soils, pavement sections, traffic and so on. Several of the MnROAD project objectives related to the development of improved mechanistic models and the development of improved pavement design methods. The Load Testing of Instrumented Pavement Sections project included strain measurements from a variety of vehicle loads, including single, tandem, and tridem axles, tire pressures, tire types, various vehicle speeds, and several different seasons. The testing and analysis resulted in the evaluation of various mechanistic models and the selection of WESLEA for flexible pavements and ISLAB2000 for rigid pavements. Many of the strain sensors, installed during construction in 1993 or 1994, no longer worked limiting the number of test cells available and the scope of the study. The LEF analysis for flexible pavements were based on only the tensile strain at the bottom of the asphalt, and were generally lower than the corresponding AASHTO factors. There were too few strain sensors available to conduct an LEF analysis on rigid pavements, however, during the selection of ISLAB2000, a number of relationships were developed that relate k-value, to other factors such as slab thickness, slab elastic modulus, and strain.
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    Pavement Rehabilitation Selection
    (Minnesota Department of Transportation, 2008-01) Dai, Shongtao; Skok, Eugene; Westover, Thomas; Labuz, Joseph; Lukanen, Erland
    The objective of the project was to outline best practices for the selection of asphalt pavement recycling techniques from the many choices that are available. The report specifically examines cold-in-place recycling (CIR), plain full depth reclamation (FDR), and mill & overlay (M&O). Interviews, surveys, and site visits were conducted at both Mn/DOT districts and counties, where relevant rehabilitation information was supplied on over 120 projects. A database was constructed to organize the details of these projects, and the parameters in the database included (1) cracking, (2) ride, (3) rutting, (4) age, and (5) traffic volume. From studying the existing rehabilitation projects in the State, Ride Quality Index (RQI) and Surface Rating (SR) were selected as the descriptors of pavement surface condition. A decision procedure based on the analysis of all available projects was developed. The decision procedure included (1) consideration of road geometrics; (2) pavement condition survey; and (3) structural adequacy evaluation. Furthermore, a step-by-step checklist was developed to provide local engineers with a simple and useful tool to follow the decision procedures. The procedure includes selection of rehabilitation method, pavement thickness design, materials mixture design, and construction.