Calculating the load on a lintel

[nafuk]

I need to calculate the loads on a lintel for a 2 m gap in a solid 9" ground floor gable wall. Loads will be the bricks above and 5 first floor floor joists. I'd like to use a Catnic CN71A with a safe working load (SWL) of 20 kN.

1. First the floor joist load. Dead load is 0.75 kNm2, live load 1.5 kNm2, total 2.25 kNm2. Room area is 5.67m2 (2.1m x 2.7m) so load is 12.76 kN Number of joists is 8 (2.2m long), so number of end bearings is 16. Load per end bearing is 16/12.76 = 0.797 kN. End bearings on lintel are 5, so load is 4 kN.

Does this look ok?

1. Now the load from the wall. As an approximation can I take the triangular weight of the bricks above? What is the conversion from kg to kN, since 102 kg = 1 kN/m2, and I need kN and not kN/m2?

If it is a lot more complicated I'll get a structural engineer etc.

Thank you.

[John Rumm]

Sounds plausable - the 1.5kN/m^2 sounds right for the imposed load on a domestic floor, although I am not sure that does not also include the dead load. Hence you may be adding 0.75 where you don't need to.

Not sure if you can use just the triangle, or if you should use the column...

The wall weight will vary depending on the type of bricks etc. Something in the region of 18 to 24 kN/m^3 is about right I think. (the higher end being the heavy blue or engineering bricks - Flettons, London stock are at the lighter end)

Weight = mass x acceleration due to gravity

so:

kN = kg * 9.81

(or multiply the mass by ten for a close approximation)

[Set Square]

Surely N = Kg * 9.81 (not kN) ?

[John Rumm]

It does indeed! Sorry, was not paying attention to what I was typing...