×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Welding HS bolt to plate

Welding HS bolt to plate

Welding HS bolt to plate

(OP)
A contractor has proposed an alternate connection to a piece of cast-in-place concrete.  Rather than cast HS bolts into the concrete with the bolts projecting upwards, he proposes to cast a steel plate with rebar projecting into the concrete welded to the bottom of the plate and HS studs welded to the top and projecting upwards.

The entire assembly will be hot dip galvanized.  What questions would you have for the contractor?

I am concerned about fatigue performance of the weld to the studs.  I am concerned about the effect of HDGalvanizing on the rebar.  I asked him if he had specified A706 resteel instead of A615.  Anything else?

RE: Welding HS bolt to plate

I would not recommend or endorse this design. First off, the question I would ask the contractor is what type of weld prep would they use for joining the HS bolt and rebar to the base plate? Do they have an AWS D1.1 or ASME B&PV Code, Section IX qualified welding procedure and welders?

Last, but probably most important, welding of fasteners is typically not good engineering practice. The heat from welding will adversely affect the strength properties of the fastener.

RE: Welding HS bolt to plate

If the studs he is proposing to use are of a chemical composition that works with welding, fine.  I don't know names but I suspect there are a number of stud manufacturers who regularly do this type of thing.  If what they are talking about is welding A325 or A490 bolts to the plate, then NO.  Neither bolt type has a chemical composition suitable for quality welding.  I would also be concerned about the ability to weld the rebar to the underside of the plate.  You would probably be better off with a welded headed stud on that side with a rebar cage that could transfer forces off of the studs into the remainder of the concrete.

RE: Welding HS bolt to plate

That's a lot more trouble than just putting in the proper anchor bolts.

Points above regarding welding are good and should be considered.  No reason to do this alternate unless there is absolutely no way the bolts can be cast into the concrete.

RE: Welding HS bolt to plate

(OP)
Thanks for the replies.

The contractor is proposing this so he can slip-form a concrete parapet on a bridge.  Many around here would rather he simply cast the parapet without slip forming, but with one set of a-bolts every eight feet or so, that is a lot of parapet to hand form.

Dinosaur

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


Resources

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