Transportation Engineering Commons^™

Evaluation Of Unmanned Radar Installations, Jerry G. Pigman, Kenneth R. Agent, John A. Deacon, Richard J. Kryscio

Kentucky Transportation Center Research Report

Several unmanned radar devices were installed on I75 in northern Kentucky in an attempt to reduce speeds. It was assumed that drivers use radar detectors to exceed the speed limit with a resulting variance between their speeds and others in the traffic stream. Therefore, a reduction in overall speeds and variance was expected to reduce the probability of accidents. Historical data indicated an unusually high accident rate for the study area.

Emphasis was placed on collection and analysis of speed-related data. In addition, a survey of radar detector usage was made and accident patterns were documented.

Speed measures analyzed included …

Evaluation Of I-75 Lane Closures, Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

A project on I 75 in Whitley and Laurel Counties during the 1986 construction season involved numerous lane closures associated with spot pavement replacement and joint sealing. Traffic congestion associated with heavy volumes and late merges resulted in the use of the following traffic control devices to supplement standard lane closure devices; 1) variable message signs, 2) supplemental lane closure warning signs, and 3) rumble strips placed in the lane to be closed in advance of the taper.

Results showed a decrease in the percentage of traffic in the lane to be closed with each successive traffic control device in …

Treatment Of Narrow Medians On Four-Lane Rural Roadways, Jerry G. Pigman, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of this study was to investigate alternatives to paved mountable medians that have been used in the past on sections of four-lane, partially controlled access roads where right-of-way is restricted. These mountable medians present obvious operational problems due to the 3-inch difference in height as compared to the through lanes. In addition, construction and maintenance problems are associated with mountable medians because of the height differential.

A telephone survey of 16 states was conducted to determine their policy for separation of rural four-lane roads with partial control of access and narrow medians. Accident analyses comparing roads in Kentucky …

Analysis Of Accidents Involving Crash Cushions, Jerry G. Pigman, Kenneth R. Agent, Tom Creasey

Kentucky Transportation Center Research Report

This report is an analysis of 127 accidents involving crash cushions in Kentucky. The primary data base was for the period 1980-82, with some additional data before and after this period. An attempt was made to document each accident with a police report, photographs, and a repair form. The largest number of accidents (63) involved a Hi-Dro cell cushion or cluster, followed by 33 accidents involving a G.R.E.A.T. crash cushion, 19 with a temporary G.R.E.A.T., 10 with sand barrels, and 2 with steel drums.

Average repair cost was lowest for the Hi-Dro cell cushion ($392) and highest for the Hi-Dro …

Survey Of Effectiveness Of Transportation Services, Jerry G. Pigman, Kenneth R. Agent, Joseph D. Crabtree

Kentucky Transportation Center Research Report

With increased emphasis on public accountability and program evaluation, the need for effectiveness measures to indicate the extent to which an agency's goals and objectives are being met is increasingly apparent. A research study was undertaken to establish and implement a procedure for monitoring the effectiveness of transportation services in Kentucky. Quantitative data for many of the effectiveness measures were obtainable only through responses from the public. Surveys of licensed drivers and bus riders were selected as data sources. This report addresses the procedures and results of the two surveys. Responses were received from 35.5 percent of the 10,000 licensed …

A High-Accident Spot-Improvement Program, Kenneth R. Agent, John A. Deacon, Robert C. Deen

Kentucky Transportation Center Research Report

As a result of an extensive before-and-after accident study, the high-accident location, spot-improvement program in Kentucky, although not a costly program, was found to have significantly decreased the number of motor vehicle accidents. Favorable benefit-cost ratios indicated that the cost of the program has represented a good investment in comparison with the resultant savings in accident costs. The spot-improvement program had little effect on average accident severity as measured by a severity index. Detailed analysis of available accident data showed that, for studies of the type reported, the 12-month period immediately prior to the date of identification of a high-accident …