We reached out to KTC for some information for a project that Vaughn & Melton was working on. Eric and staff were extremely helpful and quick to respond. The information was very detailed and helped us take our project to the next level.
Project Info
Project Request Date: 02/04/2019
Project Requested By: James Ballinger & Courtney Evans – Vaughn Melton
Principle Investigator: William Staats
Initial Inquiry
V&M asked for SPF information for a KYTC project on a two-lane rural route.
Project Write-up
KTC sent Courtney S. Evans the SPF fact sheet for rural, 2-lanes roads as well as the intersection SPF list.
Data Provided
Final Rural Two-Lane SPF and Adjustment Factors
Base Conditions
9’ lanes, 3’ shoulders, Horizontal curvature= Class A, Grade= Class A, no median, no intersections
|
Sample |
3119 |
100-200 intersections* |
|
Length |
215.8455 |
100-200 miles* |
|
Crashes |
854 |
300 crashes per year* |
|
R2 |
0.515857 |
Higher values preferred |
|
CDP |
13.5941 |
Less than 5% |
|
MACD |
43.40788 |
Smaller values preferred |
|
MAD |
0.355154 |
Smaller values preferred |
|
Theta |
1.531877 |
Higher values preferred |
|
Alpha |
-4.49214 |
(Intercept) zvalue= 8.77117005270637e-29 |
|
Beta |
0.844042 |
lnADT zvalue= 6.2937196537382e-51 |
|
StdErr |
0.273624 |
|
|
AIC |
3581.527 |
Lane width AF (Modified from HSM)
|
Lane Width (ft) |
AADT <400 |
AADT 400-2000 |
AADT>2000 |
|
9 or less (base) |
1 |
1 |
1 |
|
10 |
0.97 |
1.02+.000175*(AADT-400)/ 1.05+.000281*(AADT-400) Or 0.622776+(1302.8/(AADT+3336.65)) |
0.87 |
|
11 |
0.96 |
1.01+.000025*(AADT-400)/ 1.05+.000281*(AADT-400) Or 0.088968+(3261.86/(AADT+3336.65)) |
0.7 |
|
12 or more |
0.95 |
1/(1.05+.000281*(AADT-400)) Or 3558.72/(AADT+3336.65) |
0.67 |
Shoulder Width AF (http://www.cmfclearinghouse.org/study_detail.cfm?stid=338)
|
Shoulder Width |
AF |
Crash Severity |
Roadway Type |
Area |
|
0 |
1.145 |
All |
Two-Lane |
Rural |
|
1 |
1.12 |
All |
Two-Lane |
Rural |
|
2 |
1.03 |
All |
Two-Lane |
Rural |
|
3 |
1 |
All |
Two-Lane |
Rural |
|
4 |
0.975 |
All |
Two-Lane |
Rural |
|
5 |
0.945 |
All |
Two-Lane |
Rural |
|
6 |
0.93 |
All |
Two-Lane |
Rural |
|
7 |
0.905 |
All |
Two-Lane |
Rural |
|
8 |
0.875 |
All |
Two-Lane |
Rural |
Horizontal Curvature AF (http://www.cmfclearinghouse.org/study_detail.cfm?stid=481)
Grade AF (HSM)
|
Grade |
AF |
|
0-3% |
1 |
|
3-6% |
1.1 |
|
>6% |
1.16 |
Median Installation AF (http://www.cmfclearinghouse.org/detail.cfm?facid=24)
0.88
Testimonial
We reached out to KTC for some information for a project that Vaughn & Melton was working on. Eric and staff were extremely helpful and quick to respond. The information was very detailed and helped us take our project to the next level.
Courtney Evans
Vaughn Melton
The Kentucky Traffic Safety Data Service (KTSDS) is a program of the Kentucky Transportation Center.
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