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This Phase II study involved studying the short-term and long-term effects of the Compliance Review (CR) programs conducted in the Region 5 states of Wisconsin, Indiana, Michigan, Minnesota, Ohio, and Illinois on the Out-of-Service (OOS) rates of interstate freight-carriers based in those states. A preliminary analysis of the inspections data revealed low OSS rates based on inspection records--across all level of inspection--for the years 1993-94, indicating defective collection/interpretation of data and thereby invalidating any OOS rate analysis for this time period. Also, it was found that Level 1 and 2 inspections together constitute nearly 80 percent of all inspections records, thus marginalizing the effect of the other levels of inspection on the final results of this analysis. The results of both the short-term and long-term effects of OOS rate analysis suggest an overall positive effect of the Compliance Review program on the reduction of OOS (Event and Violation) rates of the carriers. These results are consistent over the rest of the time period (1995-97) and across three levels of inspection (Levels 1, 2, and 3). The conclusions drawn about the nature of the effects of a Compliance Review could be much better validated if the currently spurious inspections data for the years 1993-94 were restored, or a fresh analysis using later available data (1997-99) were carried out based on the same algorithms.

In October 1994, the Minnesota Department of Transportation's (Mn/DOT) Office of Motor Carrier Services sponsored nine focus groups of small shippers and motor carriers to learn more about how federal initiatives affect Minnesota's transportation community. The focus groups revealed several common issues that affect both carriers and shippers, including the following: low awareness of government agencies, services, and functions; perceived inconsistency in the application of rules and regulations; shippers' reliance on motor carriers as a source of information; inconsistent standards of loss and damage claims; and confusion of application of safety hazards. In addition to identifying perceptions about expected changes due to federal preemption of state motor carrier regulation, the research also provided insights into other timely concerns of shippers, motor carriers, and insurance companies. The report also includes recommendations in the areas of information, research, and education.

This study describes the movement of grain shipments from Minnesota to their final destinations. A sample of approximately 100 (or 20%) of Minnesota's grain elevators reported their monthly grain shipments by mode to each of nine destinations from July 1999 to June 2000. The researchers used this data to project grain shipments from Minnesota and each of six crop reporting districts by grain and by transportation mode to final destination. Minneapolis and Mississippi River ports were the most important destinations, receiving 28.4% of all shipments. Pacific Northwest export ports received 17.9%. Minnesota-based corn, soybean, and wheat processors received 16.6% of shipments. Duluth-Superior received 10.5% and Mexico received 7%. Rail was used for 494 million bushels (14.1 million tons) or 64% of all grains. Rail shipments of 50 or more cars accounted for 47% of all elevator shipments. Truck shipments accounted for 263 million bushels (7.4 million tons). Both destination and modal percentages varied substantially by grain and by crop report.

This report describes results from a series of experiments using the virtual bumper collision avoidance algorithm implemented on a Navistar tractor cab. The virtual bumper combines longitudinal and lateral collision avoidance capabilities to control a vehicle in normal and emergency situations. A programmable boundary, the virtual bumper, defines a personal space around the host vehicle. Researchers used a radar and a laser range sensor to sense the location of vehicles in front of the truck. Target vehicles that enter the truck's personal space impose a virtual "force" on the host, which in turn modifies the vehicle's trajectory to avoid collisions with objects in the field of view. Researchers tested the virtual bumper longitudinal controller under different driving situations and at different speeds. The experiments included several scenarios: Adaptive Cruise Control, the truck performing a critical stop for a stationary target vehicle, and situations that simulate stop-and-go traffic. Results from the virtual bumper longitudinal experiments were favorable. The algorithm demonstrated robustness to sensor noise and the ability to maintain a safe headway for both normal and emergency driving scenarios. Researchers currently are improving the sensing technology and incorporating a road database, which contains roadside features to greatly reduce, if not eliminate, false target detection.

This project used research to develop more effective criteria for placement and removal of spring load restrictions (SLR). Researchers investigated a method that uses a thawing index equation based on air temperatures to predict thawing events. Results showed that adjusting the reference temperature improved the spring-thaw prediction for Minnesota. Researchers compared historical SLR posting dates from 1986 through 1998 to the dates predicted using this new technique and to falling weight deflectometer and in situ instrumentation readings from 15 flexible pavement test sections in Minnesota. According to results, there was typically a week or more delay from the time that SLR should have been placed until actual posting of restrictions, which caused damage that could have been prevented. Based on testing performed on pavement sections across the state, the typical period required for pavement base and subgrade layers to regain sufficient strength to support heavy truck loads was eight weeks. In 1999, the Minnesota Department of Transportation adopted the improved procedure for placing and removing SLR. The policy uses actual and forecasted average daily temperature to determine timing of SLR. When the SLR duration is fixed at eight weeks, it is easier to plan for the end of the restriction period. Researchers estimate an increase of 10% in a typical low-volume asphalt road's life with implementation of the improved SLR procedures, resulting in a potential savings of more than $10 million annually.

Any increase in legal truck weight would shorten the time for repair or replacement of many bridges. Five steel girder bridges and three prestressed concrete I-girder bridges were instrumented, load tested, and modeled. The results were used to assess the effects of a 10 or 20% increase in truck weight on bridges on a few key routes through the state. Essentially all prestressed girders, modern steel girders, and most bridge decks could tolerate a 20% increase in truck weight with no reduction in life. Unfortunately, most Minnesota steel girder bridges were designed before fatigue-design specifications were improved in the 1970's and 1980's. Typically, an increase in truck weight of 20% would lead to a reduction in the remaining life in these older steel bridges of up to 42% (a 10% increase would lead to a 25% reduction in fatigue life). Bridge decks are affected by axle weights rather than overall truck weights. Transverse cracks in bridge decks are primarily caused by shrinkage soon after construction and are not affected by increasing axle weight. However, decks with thickness less than 9 inches or with girder spacing greater than 10 ft may be susceptible to longitudinal flexural cracking which could decrease life.

This report provides a spreadsheet model for calculating the costs of operating cars and trucks, specifically for use in planning highway projects which change the conditions under which people drive. The specific costs addressed are: fuel consumption, routine maintenance, tires, repairs, and some depreciation. This approach to estimating costs is innovative in several ways. The authors have developed a way to determine the marginal costs of actually driving exclusive of the fixed costs of ownership. They also offer methods for adjusting the costs for different conditions and guidance on how to adjust costs in the future. The authors conclude that in a case of highway driving on smooth pavement at $1.50 per gallon for gasoline, personal vehicles average 17.1 cents per mile to operate and trucks average 43.4 cents per mile. City driving conditions increase these costs by 3.9 and 9.5 cents per gallon, respectively.

This report aims at establishing a correlation between the voluntary ISO 9000 certification by motor carriers and traffic safety. The report shows that improvement of operating and quality performance improved safety performance. As part of the analysis, several ISO 9000 certified and non-certified motor carrier companies were compared based on their social and financial performance prior to, during and after the certification process. The authors have shown that there is a positive increase in performance during and after the certification process. The number of motor carrier companies certified by ISO 9000 is limited and unique. The uniqueness arises from the fact that the certified organizations haul specialized products such as automobiles and hazardous materials. That shows that most organizations are certified due to mandatory reasons. In conclusion, the observations and results have thrown light in a new direction that indicates that there exists a significant relationship between the quality assurance and safety performance of a motor carrier organization. The authors feel that further research is necessary to investigate the circumstances under which ISO 9000 and other programs for upgrading motor carrier performance help lead to an increase in safety.

This project studies the benefits and barriers of increased adoption of medium-duty and heavy-duty electric trucks, referred to as e-trucks, and presents a methodology for optimizing the location of e-truck charging stations in Minnesota. In general, e-trucks provide zero tailpipe emissions and lower operating and maintenance costs. However, some barriers to adopting e-trucks include higher initial purchase costs, lack of charging and maintenance infrastructure, limited range, and charging time. The methods presented in this study aim to address the charging infrastructure planning, which provides information about e-truck charging activities, changes in vehicle miles traveled (VMT), and potential operating cost savings.

The purpose of this project, "Trucks and Twin Cities Traffic Management," is to identify strategies that will reduce congestion for trucks traveling within and through the Twin Cities. The planning and development of most highway facilities focuses on the general needs of the majority of traffic in the traffic stream. However, the performance, function, and purpose of heavy trucks are dissimilar to those of the majority of the vehicles in the traffic stream. It is for this reason that the National Cooperative Highway Research synthesis report 314 identified a number of improvements that state transportation agencies have implemented, or are planning to implement, that focus on the unique needs of trucks to better accommodate truck-borne freight traffic. Additionally, to help reduce delays and congestion a number of urban areas have conducted studies of the unique issues trucks face. The study first identified an exhaustive list of potentially feasible strategies and then through iterative steps narrowed these down to the most promising. Five strategies were ultimately selected. The report focuses on issues related to the five strategies and their implementation.