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In 1980, Minnesota passed a new law for controlling overweight trucks. This new law allowed bills of lading, weight tickets, and other documents that indicate the weight of a truck to be used as evidence in a civil court proceeding to establish overweight violations. Under many circumstances it is no longer necessary for the State Patrol to catch an overweight truck on the road. A demand for the payment of penalties can be sent out in the mail and if not paid, a civil law suit will be initiated by the state. "Relevant evidence" of such weight documents is now used by the civil weight enforcement group of the Department of Public Safety and is proving to be an excellent addition in the restriction of illegally overweight motor carriage. This report discusses the history of Minnesota weight enforcement and the role of the relevant evidence law in constructing a comprehensive weight enforcement system.

This report examines the local economic impact associated with a proposed new bridge across the St. Croix River, linking Washington County, MN and St. Croix County, WI. The new bridge is intended to functionally replace the aging and insufficient existing bridge crossing, and expand highway system capacity to meet current and projected future travel demand across the river. The Minnesota side of the existing bridge is located in downtown Stillwater, while the new bridge and highway approach to it completely bypasses that area. This study focuses on economic impacts associated with the bypass of downtown Stillwater, but also examines economic impacts on the Wisconsin side of the river.

This report presents the results of a review of long held contentions regarding driver choice of speed and reaction to speed limits. Areas of concern that were studied included influence of the roadway environment, reaction to school speed zones and reaction to warning flashers. Results of the review show that drivers do vary their speed under differing conditions, they do not react as desired to lowered speed limits or to passive signing. They do lower speeds when they see a warning flasher in conjunction with limit signs, but not as much as is requested. There was evidence too that in some zones a lower limit may result In a more hazardous situation.

A Minnesota retrofit W-beam guardrail to concrete safety-shaped (Type J) bridge rail transition design with a separate end post was previously crash tested and found to have unsatisfactory impact performance. The design was improved with the addition of a channel rub rail and the improved design was crash tested and evaluated in this study. In accordance with guidelines outlined in NCHRP Report 230, one crash test was conducted on this improved transition design. Results of the crash test indicated that this improved design met all impact performance evaluation criteria as outlined in NCHRP Report 230. This improved transition design is recommended for approval in field applications.

This memorandum supplements the "Structural Study of Existing Lafayette Bridge No. 9800," dated March 1, 2007. The estimates of probable construction costs herein are intended to provide a comparison between the various alignment options and bridge type alternatives for selection of the preferred structure for bridge widening and also to provide information for future funding plans. The estimates are based on estimated quantities and unit price extensions, which will allow for more convenient adjustments to be made in case the planned construction year is modified. The pay quantities should remain fairly constant, whereas the unit prices are subject to a variety of influences that are often difficult to predict. A spreadsheet for each combination of alignment option and bridge type alternative is included in the appendix. These spreadsheets show estimated quantities, unit prices, and cost extensions for the more significant pay items. They also show add-on percentages and costs for minor quantities and staged construction methods under traffic. The adjusted totals have had a contingency percentage added to arrive at the total costs that are stated in the Lafayette Bridge Structural Study report. Backup information providing the basis of the estimated quantities has been provided to Mn/DOT's project manager.

The scope of work for the Lafayette Bridge Study requires the investigation of four bridge widening options. Options are defined in terms of three criteria: horizontal alignment, deck geometry, and whether or not river construction operations (piles footings, pier shafts, cofferdams, etc.) are allowed. The options are named Option 1a, 1b, 2, and 3. The distinguishing characteristics of each option are as follows: • Option 1a: Symmetrical widening about the existing centerline, bridge cross sections meet full geometric standards, foundation work in the river is not allowed. • Option 1b: Symmetrical widening about the existing centerline, bridge cross sections meet full geometric standards, foundation work in the river is allowed. • Option 2: Symmetrical widening about the existing centerline, bridge cross sections do not meet full geometric standards, foundation work in the river is not allowed. • Option 3: Northbound bridge on a new alignment east of the existing bridge, southbound bridge centered on the existing centerline, bridge cross sections meet full geometric standards, foundation work in the river is required.

New bridge decks will be designed to standards which insure a reasonably long maintenance free life. The new bridges have been grouped into three categories with a deck protective system designed to be cost effective for the anticipated exposure to de-icing chemicals in each of these categories.

A task force composed of personnel from the Offices of Bridges and Structures, Materials, Research and Standards has reviewed and analyzed existing procedures for protection of bridge decks. The objectives of the task force were: 1. To develop policy for installation of protective systems on new bridge decks. 2. To develop policy for establishing priorities and selecting methods for contract restoration and protection of in-service bridge decks. 3. To develop policy for systematic maintenance utilizing M.H.D. forces, for the preservation of in-service bridge decks which are not being considered for contract restoration. The objectives were set to protect the bridge deck investment in a cost-effective manner and within budget limitations.

This study was initiated to investigate the possible causes for excessive lamp failure rates on High Mast illumination towers in the State of Minnesota. This type of highway illumination system consists of high masts on which there are either three or four luminaires. The masts are 120 feet (36.6 meters) high and the luminaries are attached to a ring assembly that can be lowered for lamp replacement. The study consisted of two methods of analysis. The first step was to analyze numerically the complete system by employing a finite element code and to compute the motions of the complete system under typical wind conditions at the site (wind velocities between 5 to 60 mph). The second phase of the study consisted of an experimental effort during which one of the illumination towers was instrumented and motion data was collected for various wind conditions. The final phase of the study included the evaluation of the numerical as well as the experimental data that had been obtained from the preceding steps. This evaluation included the identification of modes of vibration in the frequency domain, filtering of data for acescent of modal effects, and comparisons between experimental and numerical results.

In the early 1990s, cities, counties and state agencies (primarily in the Twin City Metro area) experienced rapid growth in radio communications. The increased radio traffic on the public safety systems in the Metro created a severe interference problem among existing users. All FCC radio frequencies within the Metro area were in use, which limited system expansion and, in some cases, prohibited growth of radio systems. Interoperability among public safety agencies was hampered and cumbersome. The 1996 Minnesota Legislature funded the construction of a Metro-wide 800 MHz regional backbone system (Chapter 463, Sec.19, Subd. 3) to meet the demands of the Metro area, and provide capacity for local subsystems to join the network. The implementation of this system is in progress and will be operational in 2002. The problems in Metro are not unique to the area. Outstate public safety communications systems are facing many of the same problems that Metro faced ten years ago. For that reason, the 2000 Legislature directed the commissioners of the departments of Administration, Transportation and Public Safety to convene a planning committee to report to the Legislature on a plan for the development of a statewide, shared public safety radio system. The legislation further directed the planning committee to develop a means to include input from representatives of local governments and major system user groups. As a result of the legislative directive, an 800 MHz Executive Team was formed to study and assess the current and future wireless communication requirements, needs and concerns of the local units of government and major system user groups such as the state of Minnesota, the Emergency Medical Services (EMS) community and school districts.