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This report presents waste materials and products for highway construction. The general legislation, local liability, and research projects relating to waste materials are outlined. The waste materials and products presented include waste paving materials, industrial ash materials, taconite tailing materials, waste tire rubber materials and products, building rubble materials, incinerator ash products and materials, waste glass materials, waste shingle materials and products, waste plastics products and slag materials. For each waste category, the legislation and restrictions, material properties, construction and application, field performance, and recycling at the end of service life if available are discussed. In addition, procedures for evaluation of and selection from waste alternatives are presented. Results from a survey sent to Minnesota city and county agencies are presented summarizing current practices in waste reuse for highway construction.

This report presents the step by step installation and testing procedures developed for the load response instrumentation at the Minnesota Road Research Project (Mn/ROAD). Load response instrumentation measures such parameters as strain, deflection and pressure in the pavement layers from dynamic axle loadings. The test procedures presented were performed immediately before and after paving to check for any gross malfunctioning of lead wires or sensors. The procedures presented do not include any accuracy tests. Initial survivability of the sensors is discussed as are probable causes for failures.

The introduction of fiber reinforced plastic (FRP) dowels as possible alternatives to the epoxy-coated and stainless-steel dowels, was contemporaneous with a paucity of knowledge of their long-term performance. Although various isolated efforts had examined them on a short-term basis and produced some qualitative results or long-term predictive models, actual long-term performance in service was still unknown and unanalyzed. An experiment at the MnROAD Research facility placed FRP dowels in 2000 in some of the jointed plain concrete pavement (JPCP) panels of test Cell 52 and used epoxy-coated dowels in the remaining panels of this cell. The contiguity of this test cell with Cell 53, a JPCP high-performance concrete cell built in 2008 with stainless steel dowels, and Cell 54, a taconite JPCP cell with epoxy-coated dowels in built in 2004, facilitated a comparative analysis of performance of the 3 dowel types particularly in load transfer efficiency (LTE) and ride quality. The difference in the inception of the cells constrained a performance over time and encouraged a time-series autoregressive integrated moving average (ARIMA) analysis. Projections to 30 years showed that LTE and ride quality of FRP dowels were no different from those of the epoxy-coated dowels and the stainless-steel dowels although Cell 53 was designed and built with thicker concrete (12-in. thick) compared to 7.5-in in cells 52 and 54.

A soil sampling and testing program was conducted on the pavement embankment at the Minnesota Road Research Project during different stages of construction. The objective of the study was to characterize the embankment and granular base soils. Both destructive and nondestructive approaches were taken. Nondestructive load tests were conducted using a falling-weight deflectometer and both disturbed and undisturbed soil samples were retrieved. Falling-weight deflectometer tests were conducted at regular intervals along three different offsets on the embankment. A large diameter plate was used with modest load levels. Other data obtained during the testing program included jar, bag, and thin-walled soil samples, and dynamic cone penetrometer soundings. The falling-weight deflectometer load and deflection data were used to back calculate the elastic moduli for both a homogeneous and multi-layered system. The variability of the deflections and estimated moduli were addressed using both general statistics and geostatistical analyses. It was found that the measured deflections were highly variable due to surface irregularities such as ruts, cracks, and loose compressible material, as well as soil moisture content and density variations. The back calculated moduli computed from the inner sensor deflections were lower and more variable than those from the outer sensors. Laboratory resilient modulus tests conducted on the thinwalled samples yielded values that compared well with the back calculated values from the outermost sensors.

An extensive pavement material sampling and testing program was devised and carried out during construction of the Minnesota Road Research Project (Mn/ROAD). This guide provides comprehensive information regarding the type and location of soil and base material samples collected from the Mn/ROAD project. Information regarding nondestructive soil testing is provided which includes Dynamic Cone Penetrometer (DCP) and Falling Weight Deflectometer (FWD) testing. Material sample information provided is divided into sample types, then into proposed research applications. Sample locations and proposed laboratory tests are shown. Testing locations for the nondestructive tests conducted on the project are provided. Information listed in a "Mn/ROAD ID#" column provides a unique identification to each sample. This sample identification can be used to request samples or obtain test result data contained in the Mn/ROAD database. During construction of the Mn/ROAD project, approximately one third of the samples collected were immediately tested to characterize the subgrade layers of the project. The remaining samples were put into storage for future research needs. Appendices A, B and C contain descriptions of Mn/ROAD database tables related to soil samples and nondestructive tests. Test cell profile diagrams are provided in Appendix D.

The research shows that highway speed horn antenna ground penetrating radar equipment and automated analysis software can accurately measure asphalt thickness. To accurately measure concrete and base thickness, lower speed ground coupled equipment also must be used. In the project, researchers collected radar data for pavement layer thickness at the 40 Mn/ROAD research pavement sections to obtain accurate as-built pavement layer thickness data on the sections. A blind comparison between radar asphalt thickness data and available cores shows an R-square of 0.98. For concrete thickness, the R-square was 0.76. The report details results for base and subbase thickness and for the layer thicknesses of the four aggregate sections.

A committee consisting of Minnesota Department of Transportation (Mn/DOT) Bridge, Pavement, and Geotechnical personnel was formed to examine the present and propose a future comprehensive Non-Destructive Testing (NDT) Program. The overall intent of their study was to define the scope of Mn/DOT's NDT program focusing on the Offices of Construction and Materials Engineering, Minnesota Road Research, and Bridge, with the intent of providing basis for future investment and use of NDT methods. Several NDT devices are currently being used by the Department. They have a great potential for saving the Department time and money, and will enable the employees to perform their jobs better and more efficiently. Other NDT devices are still being investigated for their potential benefits to the Department, and have not been fully evaluated. Though these devices may ultimately save time and money and improve performance, many are labor intensive. Staff approval must be obtained before making large financial or personnel commitments. It is recommended that each of the three areas have someone in charge of the evaluation of all new equipment and methods.

Recent advances in MIMIC (Millimeter Monolithic Integrated Circuit) radar technology play an important role in the development of automated highway systems and automated vehicle control systems. This report presents results of a preliminary investigation into MIMIC-based automotive radar technology and makes recommendations for hardware evaluation. MIMIC technology integrates much of the radar transmitted, receiver, and signal processing hardware onto a one- or two-piece chip set. Massive integration leads to lower manufacturing costs and lower product costs. Moreover, this integration reduces the size of hardware, allowing the radar components to be installed in the vehicle without the need for significant modifications. As radar systems become smaller and cheaper, the demand for these systems will increase. Radar systems affect both the vehicles so equipped and other vehicles within a reasonable proximity. Before vehicles equipped with radar systems travel on public roads, their effects on traffic flow and highway safety must be investigated so that proper regulations can be developed and enforced.

With interest in collision avoidance technology for highway vehicles on the rise, this report presents an overview of current collision avoidance technology, the technical work required to bring these systems to a commercially viable product, and the societal issues that need addressing before wide-scale deployment can occur. Many questions remain about the benefits of deploying such systems, the costs, the effect of these systems on drivers, and the steps necessary to effectively regulate vehicles equipped with such systems. In addition to technical aspects, the report also discusses the issues that society will face during development and deployment of these systems, which may prove bigger impediments to deployment than technical issues. The report also recommends a research plan to perform fair, unbiased evaluations of emerging collision avoidance technology.

This report presents data using multiple-choice questionnaires to learn how drivers respond to traffic information in the form of advisory messages. Two experiments, comprising 112 participants, were conducted using the same technique and yielding similar results. The traffic information messages presented to participants varied in three respects; quantitativeness of information, imperativeness of advice, and timeliness of information. Two additional factors were examined; the amount of traffic congestion stated to be directly observable on the route and the stated accuracy of messages received in the past. Results obtained from the questionnaires indicate that the structure of the traffic message did influence the driver behavior. The propensity to depart from the planned route ahead of schedule was greater when respondents had; few exit options remaining, been told traffic levels were high, received accurate traffic information in the past, and had received messages which contained quantitative and/or imperative information. Traffic controllers with this knowledge of driver behavior could act to further reduce trip times and congestion by using the control tools currently available to them. The major conclusion we can draw from this study is that when possible and appropriate, advisory messages should contain accurate, timely, quantitative and imperative information.