Historic Bolts 1946

[jreit]

Hello. I have an old movable bridge where bolts are called out in the plans but no corresponding specification is provided. Rivets were typically more common then so I haven't been able to find a good historic reference for what bolts might have been used in that time period.

The plans are dated 1946 and state "Standard Specifications of 1941 to govern".
The bolts are 1-1/16" diameter and there is a note stating "Bolts - Forged or Machinery Steel".
These are turned bolts used in a rack.

I found a FHWA document that states there were no bolt specifications before 1947.

Given that information from FHWA, any assumptions about bolt properties would be risky but I'm hoping to not have to do field testing.

Does anyone have any insight on the bolt properties from that time period?

Link

 

[ProgrammingPE]

You could take a look at AISC's Design Guide 15 - A Reference for Historic Shapes and Specifications, which says in Table 1.4.1a that the Allowable Stress for AISC Specification Year 1941 for unfinished carbon steel bolts was 12ksi for tension and 10ksi for shear.

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[dik]

Can you imagine connections with those types of fasteners? About 40 years back I helped a steel fabricator with replacing a steel bridge bearings. We were able to lift half the bridge end, jacking on the purlins... great connection those rivets... I checked the strength using the material and the ultimate strength of them...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

 

[bridgebuster]

Unfortunately my AASHO's from the 1940's grew legs. However, in the 53 (6th edition) they state that Steel Forgings shall meet the requirements of AASHO M 102-52 or ASTM A 235-49T; the company's online subscription doesn't cover either spec.

Maybe this will help: I did a bridge rehab project not too long ago. The original design was per the 41 AASHO. We had shear locks between adjacent frame units- it's not a moveable bridge; it's a viaduct comprised of 3, 4 , & 5 span continuous steel frames. The shear locks called for 1-1/8 & 1-1/4 turned bolts, 65 ksi with an ultimate strength of 95 ksi.

The viaduct also had simple bronze rocker bearings - base plate and a curved plated - the two plates were joined with a vertical link and bolted studs. The plans said they studs have to have a minimum yield strength of 55 ksi.

 

[jreit]

Thanks for all the help everyone. I looked at DG 15 and that table has some good information.

bridgebuster - Were those properties for the turned bolts listed on the plans or did you perform any field testing? And would you mind letting me know where that bridge was located? The bridge I'm working on is located in NY.
The non-standard size of the 1-1/16" diameter bolt is a little concerning. It makes me wonder if there were any specifications that were followed when manufacturing that bolt.

 

[bridgebuster]

jreit - the designs values were taken from the plans. The bridge is in the Bronx, Major Deegan Expressway from E 138th St to just south of Macombs Dam Bridge.

 

[Lomarandil]

I don't have my copy of the Manual for Bridge Evaluation handy, but recall that it also addresses older bolts. Off the top of my head, Programming PE's 10/12ksi allowable sounds reasonable for turned bolts. You might get up to 15ksi, but don't take my word for that without verifying from another source. They could have easily been custom project specified bolts at that time.

My experience with bridges from that era is that at the time, riveted connections were more reliable/superior. That clamping mechanism is a beautiful thing.

----
just call me Lo.

 

[SlideRuleEra]

The plans said they studs have to have a minimum yield strength of 55 ksi.

Maybe this explains the 55 ksi requirement:

Above are excerpts from "Guide to Design Criteria for Bolted and Riveted Joints", Second Edition, Pages 1 and 2

 

[JStephen]

Item below is from Gaylord & Gaylord's Structural Engineering Handbook, 2nd Edition, copyright 1968 and 1979. They show the 55 ksi, although I don't see it cropping up in the A307 spec.
I also don't see 1-1/16" bolts shown anywhere, that's an oddity in itself.

 

[bridgebuster]

from the 1941 AISC

 

[JStephen]

I was searching a bit more on the 1-1/16" aspect.
First, assuming that is bolt shaft size, not head size.
And in that case, it just doesn't appear that that was ever a bolt size, period.
There is a 1-1/16"-18 UNEF thread size (EF being "Extra Fine"). The only things I see using that thread size are some assorted electrical/mechanical doohickies, not actual nuts and bolts. (

http://www.aecsinc.com/MS24265th.html

for example) You can find taps or dies or gauges for it, but no actual nuts or bolts.

 

[EdStainless]

Or are the 1 1/16" machined bearing sections with 1" threads?
We rebuilt a section of overhead in a plant that I worked in. And we destructively tested sample bolts for each application.
We found a lot of general ones in the 15-25ksi UTS range, and a lot of 55-65ksi UTS as well (mostly connecting trusses to columns).
An overhead crane in that area had used 100ksi UTS bolts.
Once we tested we could identify by markings, but not before.

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