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I am reviewing the research for low tension cable guardrail.

Cable guardrail heights: 30", 27", & 24"

Line Posts: S3x5.7 " 5'-3" with

Inline anchor Includes Posts 1-7 & spring compensators on one end when less than 1000' on both ends run of guardrail is between 1000' to 2000'.

15' is the length of need from the anchor base plate.

Cable compensator table from our old plan unsure of origin:

(See Figure 1.jpg)

Design guidance:

Grading protected by cable guardrail:

For grading 1:1.5 and steeper: slope requires using 4' max. post spacing & 4' minimum grading @ 10:1 max. behind the cable"¢â‚¬Å“ as tested MwRSF

For grading 1:1.5 to 1:3 slope requires using 16' max. post spacing & 2' minimum grading @ 6:1 max. grading behind the cable as stated in the Roadside Design Guide.

Distance to fixed object:

Post spacing 4' " no items closer than 9'.

Post Spacing 8' - no items closer than 11'.

Post spacing 16' " no items closer than 12'.

Short radius placement:

Post spacing of 16' may be used on radii longer than 715'.

For radii 443' to 715' use 12' post spacing.

Cable should not be installed on radii less than 443'

Do you concur with this implementation of cable guardrail?

The table contents contain the revised spring compression settings for cable guardrail tensioning based on research performed by the New York DOT in 1985. These tension values match the tabulated tensioning guidelines presented in Table 1 of that report. The reference for that report is as follows:

Kenyon, W.D., Cable Guiderail Tension, Interim Report on Research Project 166-1 to the Federal Highway Administration, Research Report 124, Engineering Research and Development Bureau, New York State Department of Transportation, State Campus, Albany, New York, July 1985.

I am reviewing the research for low tension cable guardrail.

-          Cable guardrail heights: 30", 27", & 24"

Correct

-          Line Posts: S3x5.7 " 5'-3"

Correct

-          Inline anchor Includes Posts 1-7

Correct

-          Spring compensators on one end when less than 1000' and on both ends for run of guardrail between 1000' to 2000'.

Correct, according to the New York DOT report referenced above

-          15' is the length of need from the anchor base plate.

Correct

Other items will be addressed in future. Thanks!