A study performed by Davis and Fitzpatrick of Minnesota Mining and Manufacturing Company, in conjunction with the Minnesota Highway Department in 1952-1953, measured changes in reflectivity of highway sign materials due to "spray" and "splash" on a two-lane, rural highway with turf shoulders. The report, entitled "Sign Placement to Reduce Dirt Accumulation" is presented in HRB Bulletin 89, "Night Visibility", 1954.
The purpose of this study was very similar - to investigate the pattern of spray from passing vehicles with respect to determining the optimum lateral and vertical placement of milepost markers for an Interstate-type highway with wider, paved shoulders.
In June, 1977 the Federal Highway Administration (FHWA) and Mn/DOT signed a Memorandum of Understanding agreeing Eo cooperate in a demonstration of the use of highway advisory radio (HAR) as a part of the I-35W traffic management system. FHWA agreed to furnish the major system components and provide technical Information and consultation to Mn/DOT, and Mn/DOT agreed to install, operate and evaluate the system. This work was accomplished under the terms of the Minnesota Basic Agreement (DOT-FH-ll-8565) as Task Order No. 5, The system was developed on a 1.26 mile (2.03 Km) section of I-35W in Richfield, and became operational in December, 1977.
The purpose of this report is to present detailed information on the HAR system, and to document the results of the evaluation study.
This ramp control project extends along southbound I-35E from Little Canada Road to Maryland Ave. (see map on page 5). Pre-timed ramp control signals were activated at Maryland Ave. and Wheelock Pkwy. in October, 1970. Traffic responsive ramp control signals were activated at Roselawn Ave., T.H. 36 (leg and loop of cloverleaf) and Little Canada Road in November, 1971. At the same time the pre-timed ramp control at Maryland Ave. and Wheelock Pkwy. was revised to include traffic responsive features. Each ramp controller operates on an isolated basis with no interconnect to other interchanges. The system usually operates from about 7:00 to 8:00 A.M., Monday thru Friday.
This report presents an evaluation of the first seven years of system operation.
The following data were gathered:
1. Freeway volumes, speeds, travel times, and accident experience.
2. Entrance ramp volumes, delays, and ramp control violation rates.
3. Alternate route volumes and travel times.
4. System maintenance records.
5. Information on comments from drivers.
As has been the situation in other major metropolitan areas, the recurring peak hour congestion problem has illustrated a need for freeway operation beyond the signing, striping, police and maintenance activity. It is now also apparent that surveillance and control measures are but a part of a necessary Traffic Management System incorporating the full range of detection, observation and response capabilities.
This report documents the activities of the Minnesota Highway Department in the area of freeway surveillance and control and how these activities are in keeping with an ultimate Traffic Management System for the seven county Twin Cities Metropolitan Area. Current projects are located on I-35E in St. Paul/Ramsey County and I-35W & 1-94 in the Minneapolis/Hennepin County area (Figure 1).
This report presents an evaluation of the first five years of operation for the I-35W traffic management system, which extends along a 17 mile section of freeway south of downtown Minneapolis. The system was developed as part of the I-35W Urban Corridor Demonstration Project which combined the benefits of traffic management with express bus transit service.
This report presents an evaluation of the use of citizen's band (C.B.) radio in the I-35W traffic management system. The I-35W system, which extends along a 17 mile section of freeway south of downtown Minneapolis, has been in operation since April, 1974. This system includes ramp control signals, bypass ramps for high occupancy vehicles, a closed circuit television (CCTV) network, a motorist information program, and an incident detection and response program. Operation of the system is computer coordinated from the Traffic Management Center (TMC) near downtown Minneapolis. A listing of reports which document the design details, system hardware and software, and system evaluation is presented in the Appendix.
