AASHTO - AASHTO Innovation Initiative - Roadway Design Issues

Roadway Design Issues

To help you determine the type of median barrier to use, begin with a review of our Lead States Team’s own analyses, including:

General Information

General Presentations

Folio/Handout

Report

General Information

Implemented High Tension system (14 miles) in 2003
Cable design to be placed at a 10’ offset from the ditch centerline
Initial 14 mile segment - Cable placed on 6:1 slope with a 60’ median, ended up being a 14’ to 16’ offset from the ditch centerline, but due to median drainage issues, the placement ended up at 16' fromt he center ditch line
Went with non-socketed system to begin with and switched to socketed system because of the ease of repair of the socketed systems
Went with High Tension for limited deflection for tight median fits
Cable heights were mounted according to the cable manufacturer
Ohio does not have standards in place, each project is site specifically designed

General Presentations

General Information

Implemented High Tension cable systems
Only use the High Tension cable systems in median applications
Require a deflection of less than 8’
Require a 6:1 slope, sometimes has to do a lot of regrading
Standard Details and Specifications available from DES-RDS
Used all concrete barrier until cable came around
Post spacing is 10’ to 16 ½’ from company to company to achieve less than 8’ deflection
Uses all milled Rumble Strips on all freeways
Takes the Cable Barrier behind the W-Beam
Barrier installation costs are as follows (barrier only)

Ø High Tension (two companies) $12 per foot $4500 per end unit

Ø High Tension (four companies) $9 per foot $2400 per end unit
Follows manufactures specifications for each barrier type
Always place at the shoulder point, 10’ to 12’ off the edgeline

Memo and Background Information

Report