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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.

The report examines policy issues related to the placement of utilities beneath public rights-of-way. The principal issues discussed are: recognition of the present and future value of the space beneath public rights-of-way in space allocation decisions, methodologies for assessing the full societal costs of utility work in congested roadways, implementation of contractual practices and fee structures to mitigate conditions involving high societal costs, and the work that would be necessary to attempt to include the impact of utility cuts on life-cycle pavement costs.

The purpose of the MINDER program is to create the common simulation resource for human factors and safety researchers in respect to Minnesota Department of Transportation (Mn/DOT) programs. To accomplish this, we have created a simulation capability to re-create part of the I-35W Metropolitan area corridor from the Cross-town commons to just south of downtown Minneapolis. Our purpose in creating this was to allow researchers on different programs to use a common simulation environment. This was the first element of MINDER which was proposed as a larger program to include other segments of the freeway systems of the Twin City Metropolitan region. This corridor is extensively instrumented for traffic flow simulation and control. Successful development and validation of such a simulation environment has allowed a number of particular advantages. It represents, to our knowledge, the first interactively simulated portion of specific urban freeway on any high fidelity simulator. It allows parallel testing of simulation versus actual driving conditions. It is capable of integration with a number of ongoing Mn/DOT, university, and commercial research projects. It provides a human factors testing facility that exceeds most capabilities that currently exist world-wide.

Five roadway sections in northeastern Ramsey County, Minnesota were monitored during 1993-95, to evaluate water quality and loading of constituents from roadway runoff. Two snowmelt-runoff and five rainfall-runoff events were monitored per year at each site. Additional samples of rainfall were analyzed to determine if rainfall was a direct source of constituent loading to roadway runoff. Roadway-runoff samples were analyzed for selected physical properties, dissolved solids, nutrients, dissolved ions, selected metals, and semi-volatile compounds. Concentrations of dissolved ions such as sodium, chloride, and metals such as aluminum, chromium, lead, and zinc were detected at much greater levels for snowmelt-runoff samples than rainfall-runoff samples. Analysis of chemical samples from rainfall indicate that rainfall was not a direct source for most constituents. Dissolved nitrate and dissolved ammonia in rainfall, however, can contribute up to one-half the amounts detected in roadway runoff. Concentrations of total phosphorus and fecal Streptococcus bacteria were greater at unguttered sites than at guttered sites. Concentrations of dissolved solids, and some metals were greater at guttered sites than at unguttered sites. This suggests that the vegetated road ditches associated with unguttered sites may filter out heavier particles such as metals and solids, while contributing additional organic matter. Concentrations of aliiminum, copper, lead, and zinc exceeded chronic condition standard limits established by the Minnesota Pollution Control Agency for metropolitan storm water from 96 percent, 52 percent, 9 percent, and 20 percent of the samples collected, respectively. Chemical loadings of specific constituents, such as suspended solids, from an individual rainfall-runoff event accounted for greater than 90 percent of the cumulative loadings of that constituent for all monitored events at site 4, for the entire study period. Length of latent period was statistically compared to constituent concentration levels of total phosphorus, dissolved sulfate, and total zinc and there was a correlation. Constituent loads were not associated with latent period. No correlation was found between traffic volumes which ranged from 1,888 to 7,172 vehicles per day and constituent concentrations or loads for this study.

This report presents the results of a one year comprehensive human factors analysis on the prototype Delco RDS device supplied by the Minnesota Department of Transportation. RDS devices provide a means of transmitting traffic information to motorist using the existing Traffic Management Center's resources. This study examined the devices and the means of transmitting information using ergonomic and human factors principles. This study expanded upon the functions of these devices and their ability to transmit information, as well as their integration within the automobile. The study was completed by examining the data entry tasks required to transmit messages and the TMC's operations as pertaining to messages and delivery to the end-users. Five tasks were completed with the following findings: Ergonomically, the prototype device requires further refinement to provide a user friendly interface. Linkage analysis and flow charting extracted areas where operations of the device was impeded by design. Simulation and on-road study elicited difficulty in operating the device while maintaining driving proficiency. Highly significant deviations were found between normal driving behavior and driving performance when simultaneously operating the device. This suggests an increase in attentional demand which is placed on the driver operating the device when they should be focused on the task of driving. Finally, assessment of data entry personnel and the TMC operations found several areas for improvement in the Crusader (TM) message assembly program interface and message content. Recommendations are provided following each task.

The success of in-car devices that aid drivers depends in part on driver reaction and acceptance. This project looks at the human factors considerations for the GENESIS Program, which studies the use of personal communication devices to deliver real-time traffic and transit information services. Researchers used vehicle simulation to learn more about the impact of the use of GENESIS devices. The report includes a discussion of human factors issues for consideration during the operational test evaluation phase and recommends suggestions to improve in-car computer screens and for future simulation studies.

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.

This research report looks at the chemical composition of reinforcing bars, and the sulfur content in particular, and their influences on the corrosion resistance of rebar. The research supports the original hypothesis--which suggests that the reduction in sulfur inclusions would benefit corrosion resistance. The reduction could result in significant savings that would more than offset the higher initial costs for these bars. To test the hypothesis, the study examined the corrosion resistance of four kinds of steel reinforcing bars; ordinary, low sulfur, copper and tungsten, and nickel. As in other series in the past, this research indicates conflicting results for different measurement techniques used to quantify corrosion rates. In addition, the mechanism that results in low sulfur bars showing a three-fold increase in corrosion life are not clear and need more study. The report recommends a long-term follow-up study on the use of both small cube and slab specimens in the laboratory, as well as full-scale specimens in the field

This project evaluates various intersection control strategies in a simulated environment and also helped establish a live laboratory for use in future testing of new control strategies. The report reviews major intersection control strategies, including the state-of-the-art strategies with adaptive and on-line timing generation features. In addition, it details simulation results for the OPAC control strategy. The NETSIM simulator created the simulation environment for a test network that included part of downtown Minneapolis. Comparison results indicate that OPAC performs best with low-traffic demands, and pretimed control was the most effective during peak periods when traffic demand reached capacity. In conjunction with this project, Minneapolis city traffic engineers installed a machine-vision video detection system at a live intersection laboratory. Located at Franklin and Lyndale Avenues, the test site will help researchers evaluate new control strategies before full-scale implementation in later phases of this research. The Phase I report is available at https://hdl.handle.net/11299/155938.

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.