Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


timbers near power cables on a bridge

timbers near power cables on a bridge

timbers near power cables on a bridge

A highway bridge over a river with a movable center section has power cables running vertically down the outside of a caisson. On each side of the cables there's a section of timber, approximately 12"x12" cross section and about 10 feet long. These are bolted to the caisson. Since I don't see any other timbers round the caisson, I'm assuming their purpose is to protect the cables from a ship striking near the cables. Is that their intended purpose?

Someone also suggested that they are there to protect ships in case they impact the caisson. If that were the case, wouldn't you expect to see additional timbers?

There's similar construction at the other end of the cables on another caisson.

What does the AASHTO standards/specifications say about the purpose or need for these timbers?

Thanks in advance.

RE: timbers near power cables on a bridge

They're not going to protect the ship - do you have a photo? - it could be a fender system to guide a vessel along the pier in the event of collision. 12 x 12's on the pier aren't going to protect the bridge either.

AASHTO Standard Specs don't cover vessel collisions; you'd have to go to the AASHTO Guide Specification for Vessel collisions. The LRFD spec has an extensive discussion.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


White Paper - Considerations for choosing a 3D printing technology
The adoption of 3D printing into major companies’ product development life cycles is a testament to the technology’s incredible benefits to consumers, designers, engineers and manufacturers. While traditional production methods have limitations in manufacturability, 3D printing provides unparalleled design freedom due to the additive method of building parts layer by layer. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close