Roof Beam replacement.

[BlueKnife]

I wouldn't remove the bottom chord, because even with the left side of the (bottom) chord broken, there was still some tension functionality served with the rest of the truss - particularly once the bottom was braced:
View attachment 833176
Yes, putting in a ridge-to-floor support probably obviates the chord. Probably.
The only thing I'd consider is putting in a few extra studs in that wall right under the king post and remove the tree trunk replacement and regain that few inches.

Otherwise I wouldn't take it any further than he's already got it... but I do look forward to the next 10 pages of this thread now that the op's done

In case it wasn't clear, I wasn't suggesting that the bottom cord could be removed with things as they are now. I was suggesting it could be done if there was a single, floor to ridge post, as you mention. But, as I said before, I think he's fine with things as they are now (at that truss).

 

[Chewwy]

. . .

have you ever heard of the collapse of the balcony at the Kansas City Hyatt. Similar setup killed over 100 people when balcony collapsed

I have heard of it and studied it. There is little similarity other than a faulty design although it is not clear that the truss actually even had an engineered design.

BTW, the Hyatt event involved elevated walkways, not balconies.

 

[Streetcar]

I have heard of it and studied it. There is little similarity other than a faulty design although it is not clear that the truss actually even had an engineered design.

BTW, the Hyatt event involved elevated walkways, not balconies.

Fabricator Modified design which greatly increases stress In member. Member failed due to increase stress

 

[Chewwy]

Fabricator Modified design which greatly increases stress In member. Member failed due to increase stress

For the truss in this thread there is little evidence of the fabricator modifying its design or that an original design ever existed. It may have been just constructed.

 

[BlueKnife]

Fabricator Modified design which greatly increases stress In member. Member failed due to increase stress

The truss in question here didn't have a "designer" per se, other than whoever built that building. That's clearly not a commercially made, engineered truss. The member failed because of the "design", not because the design was modified.

 

[Streetcar]

some people are recommending changing the truss by removing lower chord. Making center column in two pieces drastically increases stress in the joints

 

[BlueKnife]

some people are recommending changing the truss by removing lower chord. Making center column in two pieces drastically increases stress in the joints

I didn't see anyone suggest a two piece center column.

 

[Streetcar]

I didn't see anyone suggest a two piece center column.

That was the actual repair done

 

[chim]

Lots of people think they know how things work - but really don't. A number of years ago I read a lengthy piece in a farming publication my FIL subscribed to. There was a big story on building collapses during a larger snowstorm. Most were caused by owners doing mods to their buildings after the buildings were completed by the contractors.

One of the main problems was making attachments to the bottom chords of trusses for walls or stall dividers. Some were homebrew "supports" that owners added. When solid attachments were made, it changed the dynamics of the stresses and didn't allow for the truss to flex as it should. The "support" created a failure point.

They had pictures of good and bad connections. The bad ones created a solid connection between the floor and the truss. The good connections were made solid to the floor and went past the bottom of the truss, going through a guide so the truss could slide up or down.

IIRC, the Hyatt tragedy was caused by the failure of the anchors. Someone decided the ceiling rod supports were unsightly and eliminated some?

 

[BlueKnife]

That was the actual repair done

Yes. And no one suggested removing the lower cord with the repair as it is now.