Kilopond, the force exerted by gravity on a mass of one kilogram.

The hammarband distributes the force when it is positioned between the rafter and the stud.
 
As a structural engineer, I encounter both terms bärlina and standing hammarband.

I prefer the terms standing and lying hammarband because they are more descriptive. The word bärlina is also used rather carelessly by many people for things that should really be called something else, like beam or load distribution.

Not having the lying hammarband I don't think is good practice. It is also probably difficult to calculate the contact pressure according to the building code, as large pressures perpendicular to the fibers are not allowed according to Eurocode.
 
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Nissens Nissens said:
Of course, the force is distributed in the beam, but the weakest point is where the truss and the bearing line meet, that surface is 45x45 mm. And the top plate is clamped in between, it's best to add that.

I'm not saying the point is weak, but it would be interesting to know how many kN it is okay to load such a small wooden surface with. You, as an expert in the area, might be able to enlighten us on that, preferably with a source if there is one. 😊
No, that surface doesn't become 45*45 if you have a horizontal top plate between the truss and the vertical top plate (the bearing line as some want to call it). The horizontal top plate distributes the load, so the surface becomes larger. How much larger depends on what the bearing looks like, where it is along the top plate, and the dimensions of the timber involved.
 
Nissens Nissens said:
kp?
Yes, first it was kg, then kilopond, and now newton
 
I think it's time to put an end to the thread; what is starting to come now is a bit beyond the dangerous situation that TS had and has now resolved. Everything else is probably not of interest to TS.
 
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Nissens
S seniorkonsult said:
Yes, first it was kg, then kilopond and now newton.
Ok, 1kP = 9.8kN

That gives 60kP x 9.8 = 588kN per cm2

4.5x4.5 = 20.3 cm2

20.3x 588= 11,936 kN

That really sounds like very large numbers.

Doesn't feel reasonable.
 
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Nissens
R roli said:
No, the surface will not be 45*45 if you have a horizontal hammarband between the roof truss and the vertical hammarband (what some might call the load-bearing beam). The horizontal hammarband distributes the load so the surface is larger. How much larger depends on how the support looks, where it is along the hammarband, and the dimensions of the timber.
Since the hammarband is hanging in the air in the part not supported by the load-bearing beam, it can support only a marginal force. Over time, it is likely only the load-bearing beam that will support the entire structure.
 
No. 1kp = 9.8kN

The hammarbandet indeed absorbs a small force. But it distributes the force to the underlying stud so that the effective area becomes larger than 45*45mm.
 
Nissens
D Daniel 109 said:
No. 1kp = 9,8kN
Wasn't that EXACTLY what I wrote?
 
No, it wasn't.
 
Nissens
D Daniel 109 said:
The ridge beam does indeed take up a small force. But it distributes the force to the underlying stud so that the effective area becomes larger than 45*45mm.
Sure, the ridge beam acts like a "washer" and distributes the pressure over a slightly larger area by a few %. It probably makes some difference, but not a huge one, especially not on the truss side.
 
Nissens
D Daniel 109 said:
No, it wasn't.
Strange, in my reader, those are exactly the numbers I have in the calculation in message #171.

What numbers are showing on your screen then?
 
These are the right numbers. But the wrong unit. You are making the same mistake as many others by inserting a capital letter where it doesn't belong. It's not unimportant when it comes to units.
 
J
Nissens Nissens said:
Strange, in my reader, those are exactly the numbers I have in the spreadsheet in mess #171.

What numbers do you see on your screen then?
I think our friend is, as usual, careful to note that, for example, kp is not the same as kP, which is kilopascal. At the same time, he doesn't know there should be a space between the numbers and the unit 😃
 
Nissens Nissens said:
Since the hammarband hangs in the air in the part not supported by the bärlina, it can only hold up a marginal force. Over time, it will likely only be the bärlina that holds the whole thing up.
??? I think you need to draw what you mean.
 
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