padstone question

[roygbiv86]

as per previous post i am installing (yes i am getting se to do calcs and bc to look at it) rsj
probably 7"x4" (4.2mm max deflection)
although i may go for 2 7"x4" for even greater strength and stability
question is the padstones. one end is my outside wall (solid 2 brick total 9") other is single brick internal (4.5")
did i read someone say there is a minimum size on padstones ?
any info would be helpful as i want to run through a few possiblilties with the se when he calls.
also do the ends of the rsj need to be tied to the brickwork somehow to stop movement?

many thanks r

 

[noseall]

padstones generally are 2 courses deep, a single brick width and a 100mm projection each side of the steel, though this is not a precedent.

 

[^woody^]

The engineer has to design the padstone to take the load from the beam. It is not some random size, it is designed. There is no min or max size. One of the considerations is the wall it will sit on - ie if it is designed longer, wider, shorter so that it can fit on the wall.

Engineering bricks or a steel bearing plate can replace padstones

I don't know what you are thinking about in terms of "even greater strength". A beam is designed to take the load, and there is no advantage or need to make it stronger than it need to be - thats just a waste of money and back muscles when you have to lift it.

The beam ends need to be restrained. Normally bricking it in does this job, but joists can too.

 

[Static]

As woody says, padstones are there to spread the concentrated load from the steel over a larger area of the weaker brick/blockwork

The beam ends need to be restrained. Normally bricking it in does this job, but joists can too

or bolting the beam to the padstones.