Waler Connection Design 3

[OUOY]

Hi everyone,

I've started this year designing ERS systems and I'm getting a little confused when it comes to the welding and connections of waler beams.

Weld checks I'm doing seem deceptively easy and I'm wondering if it really is all that it is, most examples I'm finding for welding are for real structural connections in buildings so it's hard to get a grasp on something so simple if that makes sense.

There's no moment at the connection so I'm only doing a shear check right now for a 5/16" fillet weld though I was wondering if I need to do anything for the axial load coming in from the other waler it's connecting to.

If I'm looking at this right as well, it looks like I would only need (1) 9" weld instead of (2) 12" welds correct? Or is there any difference in splitting the up the welds for stability i.e. (1) 4.5" weld on each flange?

Thanks.

 

[SlideRuleEra]

1) Weld checks I'm doing seem deceptively easy and I'm wondering if it really is all that it is...

2) If I'm looking at this right as well, it looks like I would only need (1) 9" weld instead of (2) 12" welds correct?

1) The welds are simple because the magnitude and direction of applied forces are predictable and constant, unlike the statistical probability of loads on a building.

2) Loads are be predictable, but they are also high and continuous. Don't "cut corners" by minimizing the amount of welding that can reasonably be made at a connection. The differential cost of two welds 12" long versus one weld 9" long is trivial. Most of the cost is mobilizing the welder / welding machine and getting into position to make the welds.

http://www.SlideRuleEra.net

 

[DaveAtkins]

Normally, we assume shear is transferred via the web, because it is parallel to the direction of the applied shear force. I recommend you weld the web on both sides, not the flanges.

You can transfer shear force via the flanges, but then you need to also check flange bending.

DaveAtkins

 

[OUOY]

2) Loads are be predictable, but they are also high and continuous. Don't "cut corners" by minimizing the amount of welding that can reasonably be made at a connection. The differential cost of two welds 12" long versus one weld 9" long is trivial. Most of the cost is mobilizing the welder / welding machine and getting into position to make the welds.

Definitely understand that, cheaper than having something fail.

Normally, we assume shear is transferred via the web, because it is parallel to the direction of the applied shear force. I recommend you weld the web on both sides, not the flanges.

You can transfer shear force via the flanges, but then you need to also check flange bending.

Gotcha, so it looks like I would be using J10-1 to check that. Now if it did exceed that flange bending check, I'm assuming that's where stiffener plates would come into play at the location of the welds?

Just checking as well, the axial force has no check in a connection like this?

 

[jayrod12]

In all of our waler/soldier connections everything is fully welded with the largest single pass fillet weld possible (as long as that has enough capacity) just because when it comes to earth retaining structures, failure is a big problem, and if a weld on a waler gave way, there's nothing stopping the entire thing from coming down.

 

[OUOY]

In all of our waler/soldier connections everything is fully welded with the largest single pass fillet weld possible (as long as that has enough capacity) just because when it comes to earth retaining structures, failure is a big problem, and if a weld on a waler gave way, there's nothing stopping the entire thing from coming down.

How do you deal with inaccessible spots like this corner, weld it all before they're connected to the solider piles? Or do your welders just deal with it and have the lagging pulled out for more room? I was told we tried to avoid the welds on the bottom with the amount of slag coming into our welders faces.

 

[jayrod12]

No it gets welded in place. They weld everything they can access. And that's a bullshit excuse, slag in your face. Wear a proper welding mask then, appropriately give the steel a minor scrape with a wire brush before you start and then weld. Is overhead welding fun? no, of course not. But it's done all the time.

 

[PEinc]

Unless absolutely necessary, I assume a pined connection (M = 0) and weld as a minimum one side of each flange (vertical weld) and one side of the web (horizontal weld). I try to avoid overhead welds and rarely need stiffener plates. This has worked for me in designing several hundred braced walls and cofferdams.

http://www.PeirceEngineering.com

 

[OUOY]

Unless absolutely necessary, I assume a pined connection (M = 0) and weld as a minimum one side of each flange (vertical weld) and one side of the web (horizontal weld). I try to avoid overhead welds and rarely need stiffener plates. This has worked for me in designing several hundred braced walls and cofferdams.

That's what we try for as well and avoid moment connections at all costs. Might suggest welding the web of our connections to my superior and see if he doesn't mind the extra safety factor.