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OCR for page 198
198 g. Operates on a fully IBM-compatible microcomputer at a reasonable speed and with a manageable amount of input data. h. Is written in user-friendly terms for use by a highway hydraulics engineer. i. Includes an option that accepts user-provided sedi- ment and hydraulic resistance functions. Task 4 Make sensitivity analyses and develop guidelines for calibrating the model with emphasis on the most important data needs for calibration. Task 5 Test and demonstrate the adequacy of the model by comparing the predicted results to measured field data. Task 6 Conduct a 2-day critique workshop for 10 highway hydraulic engineers. Task 7- Prepare the final report documenting the research effort, including a user's manual and a program documentation manual. Tasks 1 and 2 are comlete. Work on the computer program progresses under Task 3. To accomplish Tasks 4 and 5, the agency is also in search of case studies and field data. Project 15-12 FY,88 Roadway Widths for Low Traffic Volume Roads Research Agency: In developmental stage Principal Invest.: Elective Date: (~30 months) Completion Date: Funds: $250,000 The objectives of this research are to develop an en- gineering analysis procedure for determining roadway width for the construction and reconstruction of low vol- ume roadways (less than 2,000 ADT) and, based on this analysis, to develop "minimum width of traveled way and shoulder" recommendations for consideration by the Geometric Design Task Force of the AASHTO Highway Subcommittee on Design for inclusion in future editions of the Greenbook. This project will consist of at least six tasks as follows: Task 1. Conduct a critical review of all pertinent literature dealing with safety, operations, and geometries of low volume roads as they pertain to and impact on roadway width. Task 2. Based on the results of Task 1, develop a data collection and analysis plan for acquiring the ad- ditional data needed to accomplish the project objectives. Variables to be included in this analysis shall include but not be limited to traffic volume, vehicle speed, percent trucks, geometries, roadway functional classification (ar- terial, collector, and local), level of service (Reference: Greenbook, Table II-6, p. 96), traffic accident data, and associated costs (i.e., traffic accident and roadway con- struction, renovation, and maintenance). Prepare and dis- tribute to the NCHRP Project Panel an interim report describing the results of this task. Task 3. Implement the plan developed in Task 2. Task 4. Based on the analysis of information obtained in previous tasks, develop an engineering analysis pro- cedure for determining roadway width for roadways with an ADT of less than 2,000. This procedure shall incor- porate an optimization of the costs and safety benefits for various roadway widths. Using the engineering analysis procedure, develop recommended roadway widths related to site conditions. It is anticipated that the traffic volume variable will require a minimum of three categories below 2,000 ADT. Prepare and distribute to the NCHRP Project Panel an interim report describing the results of this task. Task 5. Apply the recommended roadway widths developed in Task 4 and the current width criteria found in the Greenbook to low traffic volume roadways con- structed or reconstructed in three states and two counties during the last 5 years. The states and counties will be selected by NCHRP. Based on this analysis, determine the number of additional miles of roadway that could have been constructed or reconstructed in these 5 juris- dictions using the recommended roadway widths. In ad- dition, determine the associated safety impact of applying the recommended roadway widths. Task 6. Prepare a final report documenting the re- sults of Task 1 through Task 5. AREA 16. ROADSIDE DEVELOPMENT Project 16-1 FY '66 Effects of Deicing Compounds on Vegetation and Water Supplies Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Virginia Polytechnic Institute Dr. R. E. Blaser March 1, 1966 April 30, 1972 $217,300 The objectives of this study were to identify the det- rimental effects of deicing salts on roadside vegetation and water supplies and to seek means for counteracting these detrimental effects. The first phase of the study was an extensive literature review and survey of experience with regard to deicing salt use on roadways and the effects of this use on roadside vegetation, water, and wildlife. It also included identifi- cation of research needs in this problem area. This was followed by an experimental program covering the actual effects of deicing salts on specific types and~species of vegetation and on soils along highways. Efforts were made to evaluate methods of counteracting certain detrimental effects.