Use a haunch to avoid local failures of column section or web doublers ?

[Abdelrahman_Yousef]

As the title suggests , ignoring cost impact & total weight of structure.

Would you prefer adding a web doubler to make the panel shear zone safe or use a haunched connection to minimize shear force in the panel zone ?

I never liked doublers myself but would like to hear everyone's opinion .

 

[BAretired]

Would you prefer adding a web doubler to make the panel shear zone safe or use a haunched connection to minimize shear force in the panel zone ?

There is another option, i.e. to use a diagonal plate each side of the web within the panel.

Why don't you like doubler plates?

BA

 

[KootK]

My first would be a heavier column with a thicker web that doesn't need the doublers.

 

[Agent666]

Remember if adding a haunch or going to a heavier section it's making the structure stiffer and if subject to seismic loads picking up more load as a result! Chase your tail ensues...

In this part of the world we don't have the luxury of 10's of different weights of hot rolled sections for each size like other markets (US/EU, etc). We have 2 or 3 weights max per size up to 610mm deep rolled beams.

So going up a size/weight would often mean going up 3 beam sizes to get a panel zone or web thick enough to work under the beam loads. So doublers it is usually. If it's a matter of going up one weight division or something I'd do that over and above requiring a doubler plate. But if the beam and column are the same size as is often the case in low rise warehouses and the like then stiffening the panels zones with doublers or diagonal plates is usually the only way forward as opposed to 1.5-2 times the steel tonnage on the columns.

 

[human909]

This really is a case by case basis.

I'd avoid doublers and stiffeners if I can. Extra fabrication gets expensive.

In this part of the world we don't have the luxury of 10's of different weights of hot rolled sections for each size like other markets (US/EU, etc). We have 2 or 3 weights max per size up to 610mm deep rolled beams.

Though also in this part of the world we also have high fabrication costs so if it is a case of 20% increase in beam weight and doing away with a whole lot of welding then the economic advatages come to fruition. Your figure of 1.5-2 times steel tonnage on the columns, whereas my figure is 20% (in one case I did recently). But like has been said this varies, in my case we our columns were UCs rather than UBs.