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Tim Watts[_5_] Tim Watts[_5_] is offline
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Default Lateral loads near the top of a masonry wall

Yeah - I have a bit of a paranoia about lateral forces on tops of walls.
Just wondered if anyone could see any problems with this:


View of wall (plan, from top)

D
|
|
C_____|A
xxx|
xxx|
|__________E
B

xxx is a 390mm deep wall mount network cabinet (6U or 9U) weighing
12-15kg and carrying another 30-ishkg of load from switches etc.


All walls are single thickness brick and the cabinet will mount near the
top of the wall which stops at the ceiling.


BD is a main load bearing wall so does have the weight of the dormer
floor above on it. AC and BE do not have any top load.

BD is topped with a conventional wooden wall plate.

Point B near enough also has a pillar supporting part of the dormer roof
on top

Planning on screwing into the 2nd or 3rd course of brick from the top.

So if xxx is screwed to AB, it benefits from both the kicks in the
adjoining walls and some load on top.


Lateral force at the top of the cabinet pulling out the screws will be
180-240N depending.


Another way of phrasing the question: would you hang a boiler up there?
Because this is a less heavy but it's not trivially light either.


Cheers - Tim




Working:

I reckon the top bolts on the cabinet will have a lateral pull out force
of around 243N or 24kg-f

(450N acting in the center of the cabinet 0.2m from the wall and
assuming a 6U cabinet which is 0.37m high)

450*0.2/0.37=243

reducing to 180N or 18kg-f for a 9U cabinet.