Other Mild Steel Materials besides 60 ksi?

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RichRotto
Other Mild Steel Materials besides 60 ksi?

It appears that only AASHTO M31(A615) Grade 60 rebar is supported. I am trying to model a bridge rehab project with existing girders with 40 ksi stirrups. Is it possible to add different mild steel materials besides 60 ksi steel?

Pickings
re: Other Mild Steel Materials besides 60 ksi?

Rich,
You are correct, PGSuper only supports grade 60 rebar at this time, and unfortunately, I don't know of any immediate plans to add more steel types. Do you see a large need for this? What other types besides grade 40 are needed?

Richard Pickings, P.E.
BridgeSight Inc.

RichRotto
Other Mild Steel Materials besides 60 ksi?

Other steel would be ASTM A615 Grade 75 (uncoated corrosion resistant)and Grade 40 as well.

Rich Rotto, P.E.

Rick Brice
Rich, I'm added ASTM A615

Rich,
I'm added ASTM A615 Grade 40, 75, and 80 as well as A706 Grade 60 and 80 to PGSuper. From the material I've received from CRSI, it looks like A615 Grade 40 bars are only available in #3, #4, #5, and #6.
Does this seem correct to you?
 
Rick

RichRotto
Thank you

Yes, however, the original plans I am looking at show 2#7 bars at 40 ksi as well in the ends of the beams.

Rich Rotto, P.E.

Morgan Trowland
other rebar grades

I was trying to adapt your program to use in Canada but I can't enter the rebar grade that I need. Could the rebar grades not be defined as you have the concrete grades with full customization possible?

Morgan
PS Thanks for developing this program.

Pickings
 Morgan, It is much more

 Morgan,
It is much more difficult to add a feature to enable library input for rebar grades than it is to add a few new hard-coded bar grades. Do you have list of bar grades that are commonly used in Canada, and/or a reference for them? We could probably add the grades for the next version of the program.
Also, I'm not familiar with Canadian bridge codes, but am very interested to hear what modifications are required to get PGSuper working for Canadian use. Are there any major shortcomings in the program that make it difficult?
Regards,
Richard

Richard Pickings, P.E.
BridgeSight Inc.

Morgan Trowland
canadian rebar

Richard,
It's always 400MPa yield rebar here in Canada.
Technical spec is: CSA G30.18M GRADE 400

Also we'd need the metric rebar sizes.
10M - 100mm^2
15M - 200mm^2
20M - 300mm^2
25M - 500mm^2
30M - 700mm^2

With those two things we'd be able to make use of it here. I adjusted the stress limits, load factors and phi-factors to match the Canadian Code. The losses, creep & shrinkage calculations are a bit different to the Canadian code but we'd let that slide. The Canadian shear calculation is slightly different so I've made an excel sheet which I can dump the PGSuper design report into and then it does the shear check to Canadian Code.
I'm having a look through the source code to see if I can make the essential changes myself. Still amazed that such a great program is free.

Morgan

Rick Brice
Morgan,   Are there other

Morgan,
 
Are there other grades for rebar that should be considered? For example, it is common in the US that older bridges used 40 ksi rebar and PGSuper supports that for load rating. Also, AASHTO is on the verge of providing specific provisions for 80 and 100 ksi bar. Is there a similar movement in Canada?
 
Rick
 
Richard Brice, PE
Software Applications Engineer
WSDOT Bridge and Structures Office

Morgan Trowland
other Canadian rebar grades

Rick,

There are also 300 & 500 MPa grades in the Canadian Standard but they are uncommon. The rebar grades on old bridges vary a lot and I can't give you any advice on that, other than allowing a user specified Fy would be useful for load rating jobs.

Morgan Trowland, PEng.
Infinity Engineering Group

Emilie Hudon
Welded wire fabric reinforcement

Hopefully this thread is still monitored because my question is related. For shear reinforcement with NU girders we use steel welded wire fabric (ASTM A497 or AASHTO M221 with fy = 70 ksi). Typical sizes are D18 and D25. Those sizes are not available in the drop down menu for the steel rebars. Does anybody have a workaround? Or any chance it could be added? I am using the WisDOT version.

Thank you

Rick Brice
Welded wire fabric reinforcement

The best workaround I can think of is input equivalent bar reinforcement.

(fy WWR)(Area WWR)/(S WWR) = (fy Bar)(Area Bar)/(S Bar)

Solve for (S Bar)

This is on the To Do list, but not high priority. WSDOT designs stirrups assuming bars and permits equal area substitution for WWR.

Maybe you could encourage NDOR to sponsor development of WWR support in the software.

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