Large angle fixed to wall

[robert6172]

Hi everyone,

I'm a sign maker and have a sign to fix but I'm not sure if I'm going a bit too far. I'm hoping to fix a 4mm piece of folded steel 340mm x 340mm , 2 metres in length to brickwork with 5 sleeve anchor bolts, which are 80 mm down from top, spaced equally. Is it asking too much? Any input would be appreciated.

Robert.

 

[desertfox]

Hi robert6172

From your post I take it that the 2m length is sitting horizontal. Secondly what sort of weight is this angle taking apart from its own and how far out from the wall does
this weight act? Finally what size bolts are you using?
If the 2m is horizontal and all bolts are 80mm down from the top of one face of the angle then all the bolts will share the load equally.
If the 2m is vertical then all the bolts will experience different loads.
Please clarify your situation.

regards

desertfox

 

[robert6172]

Hi Desert Fox,

The angle is horizontal and will support an aluminium 'tray' sign (like a box lid) which is 2350mm x 575mm, 3mm thick with 145mm returns and will slide on to the end of the angle. The bolts I have are 10mm x 85mm and I've been told they will 'hold a house up' but I'm looking for other opinions. I'll be drilling into brick, not masonary.

Many Thanks,
Robert6172

 

[desertfox]

Hi robert6172

I have calculated the loads on the bolts assuming that they are 10mm diameter.The weight of steel angle is about 42.5kg and that of the aluminium tray 17.69kg.
Assuming that the aluminium tray exerts its weight at a distance of 314.5mm from the wall and that of the steel at 86.49mm from the wall I calculate a tensile load of 70N in each bolt and a shear load of 118N on each bolt.
These loads are quite small for say an M10 bolt and produce
very low stresses so if the bolts themselves shouldn't fail, however I do not know how good an adhesion the bolts have in brick nor do I know the bolt material you are using and finally will the aluminium lid be subject to any other loads ie:- wind load which might increase the bolt forces.

regards

desertfox

 

[robert6172]

Thanks again Desert Fox,
There won't be much wind hitting the box and apparently these bolts have good adhesion into brick. I'm thinking about a bolt all the way through to the other side with a large washer. This is a lot more work but would hopefully do the trick, but if the first method will suffice then would like to stick to that. The bolts appear to be a pale straw colour - maybe galvanised and were purchased from Turner Fixings in Sale, Manchester.

Thanks again,
Robert6172.

 

[desertfox]

Hi robert6172

Thanks good luck with your project.

desertfox

 

[zcp]

your bolts sound large enough, but you may want to get someone to check out your local building code and see what loads you are required to take into account. unless your sign is inside, there will be some wind load and it could be significant. your connection from the angle to the sign should also be checked. in signs, sometimes deflection is the problem as you don't want your sign to "look" bad.

ZCP

http://www.phoenix-engineer.com

 

[UcfSE]

Have you tried looking up the anchor with the manufacturer? Hilti has capacities for HLC Sleeve anchors in to red brick in metric units. You may have to call the manufacturer to find out if the brick must be solid or if they may be hollow.

If the brick are hollow, you may have a hard time getting the sleeve anchor to grab, and may damage the brick if the bolts are overtightened. You might consider a small epoxy anchor, such as the Hilti HIT HY 20. I only mention Hilti because I am used to their product. There are many out there from other manufacturers that are quite acceptable.

Absolutely look in to the minimum required edge distances and spacings of the bolts to help prevent damage to the brick and possible premature failure of the bolts. You're loads are very small it seems, but I would stick to the manufacturer's recommendations anyway if it were me.

 

[vonlueke]

robert6172: Assuming wind gusts of 50 m/s, I get a leeward suction pressure on the sign of at least 880 Pa, which would generate a bolt applied tensile load (after the counteractive gravity load is subtracted) of 207 N. This assumes the vertical leg of your angle is pointing upward, instead of downward. When there's no wind, the bolt applied tensile load is 70.2 N, and the transverse shear load is 118 N.

These applied loads are minuscule. So the vast majority of shear pull-out stress (on the brick material) will be due to your bolt installation preload. What bolt installation torque do you plan to apply when you install your bolts? Just ensure it doesn't exceed the maximum recommended installation torque for your particular anchor in brick (nor half the tensile ultimate strength for your bolt material). Perhaps check hilti.com technical library if you have a login account, to see if they state a maximum allowable installation torque for your anchor in hollow brick. What is the property class of your M10 bolt (stamped on the bolt head)?