792 resultados para Multilane highways.
Resumo:
This study had three objectives: (1) to develop a comprehensive truck simulation that executes rapidly, has a modular program construction to allow variation of vehicle characteristics, and is able to realistically predict vehicle motion and the tire-road surface interaction forces; (2) to develop a model of doweled portland cement concrete pavement that can be used to determine slab deflection and stress at predetermined nodes, and that allows for the variation of traditional thickness design factors; and (3) to implement these two models on a work station with suitable menu driven modules so that both existing and proposed pavements can be evaluated with respect to design life, given specific characteristics of the heavy vehicles that will be using the facility. This report summarizes the work that has been performed during the first year of the study. Briefly, the following has been accomplished: A two dimensional model of a typical 3-S2 tractor-trailer combination was created. A finite element structural analysis program, ANSYS, was used to model the pavement. Computer runs have been performed varying the parameters defining both vehicle and road elements. The resulting time specific displacements for each node are plotted, and the displacement basin is generated for defined vehicles. Relative damage to the pavement can then be estimated. A damage function resulting from load replications must be assumed that will be reflected by further pavement deterioration. Comparison with actual damage on Interstate 80 will eventually allow verification of these procedures.
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The good news is that safety belt usage on municipal road systems (city streets) increased 1.07 percent. This is encouraging since more than 45 percent of all motor vehicle crashes occur on city streets, and usage on the municipal road system has consistently been the lowest of the road systems studied. In communities where usage is good, enforcement and public education must be maintained in order to improve usage further; in communities where usage is still low, enforcement and public education must both be increased. Usage on the primary system (U.S. or state highways) rose 1.01 percent from the previous year. This is also welcome news because almost half of all fatalities (49 percent) occur on the primary road system. There was a decline in interstate belt use (-1.45 percent). Despite this decrease interstate usage is still traditionally the highest of all roadway categories presumably because the longer trips, higher travel speeds and large number of vehicles cause drivers to assume there is greater risk.
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List of information of Bid Proposal Holders
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This report is the product of a first-year research project in the University Transportation Centers Program. This project was carried out by an interdisciplinary research team at The University of Iowa's Public Policy Center. The project developed a computerized system to support decisions on locating facilities that serve rural areas while minimizing transportation costs. The system integrates transportation databases with algorithms that specify efficient locations and allocate demand efficiently to service regions; the results of these algorithms are used interactively by decision makers. The authors developed documentation for the system so that others could apply it to estimate the transportation and route requirements of alternative locations and identify locations that meet certain criteria with the least cost. The system was developed and tested on two transportation-related problems in Iowa, and this report uses these applications to illustrate how the system can be used.
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There is now a nationwide effort (the Scenic Byways Movement) to focus attention on the need to develop scenic byways and on their potential for enhancing tourism and recreation; to create coalitions and strategies to actually develop the byways; and, alternatively, to see that the job gets done. As part of this nationwide effort, the Transportation Departments of Iowa, Kansas, Missouri and Nebraska sponsored this project so they might obtain guidance related to Scenic Byways programs that may be developed in each state. The following issues are addressed in this report: scenic quality, road safety, scenic byway designation, and scenic byway information.
Resumo:
In order to determine the adequacy with which safety problems on low-volume rural roadways were addressed by the four states of Federal Region VII (Iowa, Kansas, Missouri, and Nebraska), a review was made of the states' safety policies. After reviewing literature dealing with the identification of hazardous locations, evaluation methodologies, and system-wide safety improvements, a survey of the states' safety policies was conducted. An official from each state was questioned about the various aspects and procedures dealing with safety improvements. After analyzing and comparing the remarkably diverse policies, recommendations were made in the form of a model safety program. This program included special modifications that would help remediate hazards on low-volume rural roadways. Especially encouraged is a system-wide approach to improvement which would cover all parts of the highway system, not just urban and high-volume roadways.
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Weekly letting report
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This Task A Report summarizes the initial activities of the U.S. 20 Corridor Development Study. Task A constitutes a review of the portion of existing U.S. 20 from the Nebraska state line on the south side of Sioux City to the junction with U.S. 169 south of Ft. Dodge. · Preliminary study findings for this 119 mile corridor are summarized below.
Resumo:
In February the U.S. 20 Corridor Development Study's Steering Committee met to review Report A. At that meeting the Committee selected seven alternatives to be evaluated from a cost and traffic perspective. This report, Report B, presents the cost and traffic evaluation of these seven alternatives. This Report B and its cost and traffic estimates will be reviewed at the next Steering Committee meeting. At that time it is possible that, based on the traffic and cost estimates, one or more of the alternatives will be eliminated from further consideration. After that meeting the Consultant will initiate the more in-depth analyses, including the economic feasibility
Resumo:
This study examines the feasibility of making a major financial investment in the improvement of U.S. 20 between Sioux City and Fort Dodge, Iowa. This 119-mile (191-km) highway segment of U.S. 20 currently includes 97 miles (156 km) of 2-lane highway and 22 miles (35 km) of 4-lane highway (on the west end near Sioux City and a short section near Holstein). This 119-mile (191-km) segment is predominantly rural in nature, and serves a region of Iowa that has not been economically prospering. Local business leaders and residents have long desired major improvements to this highway segment, not only because of the safety and travel efficiency implications, but also because of the belief that the highway, as mainly a two-lane facility, is retarding the corridor area's economic growth and well being. The study was divided into five sequential tasks: (A) Evaluation of Existing U.S. 20; (B) Improvement Alternatives, Costs and Traffic; (C) Screening of Alternative Candidate Improvements; (D) Economic Feasibility Analysis; and (E) Interpretation and Comparisons.
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The spirit behind the creation of the task force is one of good government. It rests upon the basic premise that taxpayers demand the best service possible for their tax dollars. Combine this demand for efficiency with Iowa's aging roadway system, and a projected increase in the state's vehicle miles traveled, the need to examine cost savings becomes apparent. Beyond the rational for good and efficient government, however, is a major concern for potential future reductions in Federal highway funds. Iowa is likely entering a period of needing an expanded transportation system with at best a static capacity for maintenance and construction.
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This report documents the results of the field inventory and evaluation of the nominated routes. Data is provided describing the visual and heritage character of the nominated routes and locations important to this character. Graphs, displays and maps were produced using the rating system described in the Iowa Scenic Byway Designation Guide. Discussions of specific inventory procedures and evaluation techniques can be found in two reports, Iowa Scenic Byway Evaluation, December 1992, and Iowa Scenic Byway Evaluation, November 1995.
Resumo:
This report documents the results of the field inventory and evaluation of the nominated routes. Data is provided describing the visual and heritage character of the nominated routes and locations important to this character. Graphs, displays and maps were produced using the rating system described in the Iowa Scenic Byway Designation Guide. Discussions of specific inventory procedures and evaluation techniques can be found in two reports, Iowa Scenic Byway Evaluation, December 1992, and Iowa Scenic Byway Evaluation, November 1995.
Resumo:
This report is submitted pursuant to a contract dated August 30, 1967, between the Iowa State Highway Commission and Howard, Needles, Tammen & Bergendoff, Consulting Engineers, in connection with studies determining (11,A) alternate pavement designs, and (11,B) criteria for geometric design studies. Included herein is that portion of the report covering Paragraph 11,A, comprising preparation of alternate type pavement designs (Portland Cement and Asphaltic Concrete) for the Cedar Valley Freeway and proposed US-518 from 1-80 to US-30. These alternate pavement designs consider quality and availability of aggregates, soil conditions and traffic information, to determine details and dimensions of pavement design. Comparative cost studies were prepared from alternate design data and recommendations as to pavement type are presented for Commission review.
Resumo:
This response is prepared to provide the public and its elected representatives with certain information which we believe to be of importance in selecting the size and type of highway network to be supported by the people of Iowa.