Contact US

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!

*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

permanent mobile maintenance platform design for bridges

permanent mobile maintenance platform design for bridges

permanent mobile maintenance platform design for bridges

I'm interested in design standards and specifications if any are available for this. The contractor just said want this on every bridge and span on a project I'm working on and I have no idea were to begin. If any of you know something about designing this type of platforms I would appreciate your help. Thank you!

RE: permanent mobile maintenance platform design for bridges

I'm having trouble understanding what is meant by "permanent mobile". Do you mean permanently mounted to the bridge, but able to move along it?

There are many mobile inspection vehicles for sale or rent.




RE: permanent mobile maintenance platform design for bridges

Thank you for the response OSUCivlEng. Yes this platforms will be permanent mounted on the bridge and need to be mobile to perform inspections and maintenance works for the entire span as per contractors request.
They don't want a mobile truck inspection for this.

RE: permanent mobile maintenance platform design for bridges

You mean a traveller. I've never designed one but have rode on a few. They are usually made of small wide flange or channel sections supporting metal grating. The sides are usually angles. The Travellers ride on rails that hang from either the web or bottom flanges of the supporting girders. I have to look through my files, may have something. You're going to need a mechanical and an electrical engineer.

RE: permanent mobile maintenance platform design for bridges

Bridgebuster's summary is correct.

I've never seen a design code or reference intended specifically for travelers. The closest I've come is some of the material for (underslung) crane wheel loads, which is an important design limitation. Otherwise, all the work I have done has been per AISC (and like BB, I've excluded the mechanical and electrical scope).

The name is a long story -- just call me Lo.

RE: permanent mobile maintenance platform design for bridges

@George89Ro - attached is a traveler rail drawing. A few years ago I did a job for a contractor involving a long span bridge that had several travelers. Mywork had nothing to do with the travelers. When I get I home tonight I'll take a look to see if any of the drawings provided to me show traveler details.

RE: permanent mobile maintenance platform design for bridges

I don't have the traveler drawing but you can get a glimpse of it in the background. The platform with the yellow chain is a temporary platform. The part that appears to be an "upper level" is really a safety cage for the access ladder and a platform for some electrical equipment. This one has a horizontal frame as a bumper when it gets close to a pier.

RE: permanent mobile maintenance platform design for bridges

I have never came across design code relating to this specific item, although in the past I have designed and used some.
The live load shall depend on intended use, and shall be 30-50 psf, plus concentrated 750-1000 lbs at any location, non-concurrent.
As travellers are installed on the long span bridges, these are not specifically covered by AASHTO, or other bridge codes, so the design specification shall be discussed with the bridge owner.
Other interesting aspects of the traveler design are the propulsion system and power supply, which could external, or internal by small generator installed on the platform. Catenaries are prone to corrosion and dirt, and coiling or folding cables tends to tangle frequently, so generator is typically a preferred choice.
There is some interesting link covering the subject: http://ravenelbridge.net/traveler.php

RE: permanent mobile maintenance platform design for bridges

Sounds like some type of P3 design/build/maintain deal if the contractor is asking for this. "every bridge and span in the project", how many bridges and spans and what type of bridges? Steel/concrete girder/truss/stay cable?

Also, from these things, you can't reach everywhere. You may have elements that require hands-on inspection and a snooper may be needed anyway. Talk to them some more about what they want/need and intend to accomplish. Depending on how many bridges there are, unique configurations of travelers you need to design/build/maintain and operating costs, they could be getting close to the cost of just buying a snooper (300K-500K).


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


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. 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