Rsj bearing help???

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Recently had an rsj installed as dinning wall has been removed. Rsj sits on internal skin on a pass time, but only has 80mm bearing on each side? Will this be okay??

Thanks in advance
 
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Yes on a concrete padstone
Span is 2850mm
178x102x19 ub

Thanks
 
Yes on a concrete padstone
Span is 2850mm
178x102x19 ub

Thanks

Your builder has used a 3.0m beam -I would've thought either 100mm or 150mm is usually the minimum (cant remember which)
 
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Although you would usually look for a 100 bearing, 80mm will be OK for the loading normally found in a domestic setting.
 
The crushing strength of the average concrete padstone is around 50 N/mm²; when safety factors are taken into acount, this is reduced to around 20 N/mm².
If the beam is 102mm wide, and the bearing is 80mm, that gives a contact area of approximately 8,000 mm², so that the maximum load allowed on the padstone surface would be 20 x 8,000 N = approx 160 KN.
This is way, way above the load that will show in the SEs' calculations for the beam; it is not a problem.
There are other factors to be taken into account when using a short bearing, but in practice they would not apply in a domestic situation where the loads are relatively low.
 
The crushing strength of the average concrete padstone is around 50 N/mm²; when safety factors are taken into acount, this is reduced to around 20 N/mm².
If the beam is 102mm wide, and the bearing is 80mm, that gives a contact area of approximately 8,000 mm², so that the maximum load allowed on the padstone surface would be 20 x 8,000 N = approx 160 KN.
This is way, way above the load that will show in the SEs' calculations for the beam; it is not a problem.
There are other factors to be taken into account when using a short bearing, but in practice they would not apply in a domestic situation where the loads are relatively low.

Its quite amazing really -it always looks so dodgy when you see a biggish steel with just 100mm bearing -I can see the logic in the maths though.
 
I'll chip in with the ubiquitous "what do the design calculations say"?

Or are you printing out a thread from DIYnot and submitting it to the council for approval? :cautious:
 

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