Analysis of safety impacts of access management alternatives using the surrogate safety assessment model : final report.
-
2017-06-01
Details:
-
Creators:
-
Corporate Creators:
-
Corporate Contributors:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
TRIS Online Accession Number:1648348
-
Corporate Publisher:
-
Abstract:The purpose of this study was to evaluate if the Surrogate Safety Assessment Model (SSAM) could be used to assess the safety of a highway segment or an intersection in terms of the number and type of conflicts and to compare the safety effects of multiple access management alternatives with less time, less cost, and less uncertainty than the traditional safety analysis methods. To meet the purpose of the study, two study sections, one on University Parkway in Orem and Provo and the other on Main Street in American Fork were selected and analyzed. Based on the findings from the calibration of SSAM on the University Parkway study section, an evaluation of the effect of converting a two-way left-turn lane (TWLTL) to a raised median on a section of Main Street in American Fork was performed using SSAM working on VISSIM simulation’s trajectory files of the study section. The analysis showed that a raised median would be much safer than a TWLTL median for the same level of traffic volume. Approximately a 32 to 50 percent reduction in the number of crossing conflicts was achieved when a raised median was used in lieu of a TWLTL. The analysis showed that annual average daily traffic (AADT) of about 34,000 to 38,000 veh/day would be the demand level where a TWLTL median is recommended to be replaced with a raised median for the four-lane study section. Also found was that the performance of a raised median might begin deteriorating once AADT becomes approximately 42,000 to 44,000 veh/day at the study section. In summary, the study concluded that the combination of a simulation software program with SSAM could be a viable, surrogate approach for evaluating and comparing the safety effects of multiple access management alternatives.
-
Format:
-
Funding:
-
Collection(s):
-
Main Document Checksum:
-
File Type:
Supporting Files
-
No Additional Files
More +