Big sign H 4’xW18’ to be fasten to a block wall 1

[Marc Rogue]

Hello guys, I was given the task to design the connection for a sign to be supported by a block wall. I came up with 2 rectangular hss3.5”x3.5”x5/16”
Per support Top and bot connected to the wall ( total of 4 supports) spaced every 4’ or so. My question is my approach was to firstly calculate wind loads(I’m in Florida) using asce 7-22 chapter 28 and then proceed to analyze the load on the sign due to wind with an eccentricity of 1.5” from the c/l of the top HSS. My question is the concrete screw manufacturer provides specification for shear and pull out strength but not tensile strength. Also the screws would be going into blocks which may not be filled with grout so I don’t feel to confident they would hold. Anyone has experience with this?

 

[driftLimiter]

The published pullout strength is basically the tensile capacity that is limited by CMU breakout, or pullout of the fastener from the wall.
You would combine shear and tension to check these anchors.

I think you will want to ensure that the anchors land on grouted cells, anchor capacity without grouted cells is very low, and its not a very reliable connection.

 

[Marc Rogue]

Thank you for the prompt response

 

[JedClampett]

You can either fill the applicable blocks with grout (no fun, but doable) or use the types of epoxy anchors with screen sleeves.
I'm a little confused by,

provides specification for shear and pull out strength but not tensile strength

as tensile strength is the same as pullout strength.

 

[dhengr]

Marc Rogue:
Those four support frames at 4' o/c could as likely be, three sided, angle iron frames with a diagonal kicker from the top angle, immediately behind the sign, down to the bot. angle at the wall support plate. That is, a top horiz. angle, a bot. horiz. angle, and a vert. angle at the back of the sign can, and with 2 base pls. for the wall attachment on the horiz. angles. How far away from the wall is that 1k sign? You should find out what the makeup of that existing CMU wall is. You can not attach only to the face shell of the conc. blk., or pull/push on just one blk. You have to grout some of the blks. immediately around each of your attachment points to make the wall work and to make your attachment bolts/screws work. You could also use through bolts with backup pls. on the inside.