Bent plate in lieu of steel relief/shelf angle

[ceci1628]

We have a project that requires an L8x8x1/2 cut to L8x7x1/2 for architectural reason. We're in the CA phase, and the contractor is asking to subsitute this cut angle with a bent plate. They claim that cutting the leg of the angle will result in twisting. Has anyone encounter this and is it true? Are there any other concerns for using a bent plate to support cmu veneer (@ every floor)?

Thanks in advance.

 

[jike]

We have required angle legs to be trimmed before with no problem that I am aware of but I wouldn't be surprise if it does cause some twist from the built in residual stresses that are relieved.

 

[jike]

We have also used bent plates for shelf angles.

If you have a low floor to floor, you might consider providing shelf angles at every other floor.

 

[rb1957]

personally, i don't see it (trimming the flange causing warping/twisting) unless they're using a very aggressive method (maybe heating the angle, rolling it flat, trimming the width, folding it back). how'd they trim it ? (saw, water jet, flame torch, "gang-drill" ?)

 

[kingnero]

it's not uncommon for hot rolled sections to warp after altering (machining, cutting, ...).
Flame cutting will guarantuee banana shaped objects.

 

[nhstruct]

I just had the opposite situation we spec'd a 8"x7"x3/4" bent plate for a releiving angle, but the contractor wanted to us a L8x8x3/4, we let them use the cut angle. I don't think it is onsite yet, but if it is distorted, we will have them replace it.

 

[a2mfk]

Is their a difference in the mechanical properties if they are both A36 steel? Then the bent PL should actually get a little strength increase because of the bending, the way HSS shapes get the bump up to 46ksi. Or am I way off?

I have used bent plates countless times to replace angles and never given it a thought.

 

[ceci1628]

I'm not sure how they plan to cut it. It was not a submittal yet, but an email request to see if it's feasible. We have granted the substitution, so hopefully this is not a disaster.

@a2mfk
You're right, the bent plate and steel angle will both be A36 steel. I was worried about the method used to bend the plate and any damages induced. Perhaps I am worrying too much. Rect. or Square HSS is a different material strength (A500 grade B), therefore it has 46ksi.