Bending Capacity of a Steel Plate

[dursunlutfu]

Hi folks,

I am designing a base plate connection for a steel framed pergola. Because the new pergola will be located on an existing concrete deck and retaining wall, I need to design the column base plates to take the moment. As per my calcs threaded rods are okay for pull out. My only concern is the bending capacity of the plate. I would like to get some input regarding the bending capacity check of a plate. I reviewed the AISC Steel Design Guide for Base Plate and Anchor Rod Design, however, I do not think that my case is applicable to that.
My lateral force is only 1 kips.

Thank you all for your time and energy !

 

[BAretired]

Your detail is not going to work. How did you arrive at a moment arm of 12"? The wall is only 8" thick. If threaded rods are placed 3" from the wall face, d = 5".

Also, the four rods on the windward side of the column cannot all provide equal tensile resistance. Those nearer the column will provide more resistance than those further away.

BA

 

[dursunlutfu]

@BAretired Sorry for not being clear with my explanation of the case. I designed the threaded rods for the worst case uplift by considering them taking the equal tensile resistance, which are the ones closer to column. Also, columns located on the north line are taking the lateral only at east west direction. Columns located on the south line are taking both east west and north south lateral.
I am transferring the entire north south lateral to those columns located at the south line which will be connected to the side of the wall. That’s why my only concern is about the bending capacity of the plate.

Thank you!

 

[amain002]

- I assume the loads shown are not factored load?

- Are the anchor bolts 3/4" Ø with 3 1/2" embedment? Does the edge distance and spacing requirements meet for the anchor bolts ? I assume this case is similar to a turn down slab?

- you mentioned concrete slab over a retaining wall above. Is the slab tied to the wall for any uplift condition?

Like BAretired mentioned as well, I am also bit concerned for the base connection?

 

[BAretired]

I still don't understand the problem, but the factored bending capacity of an 8"x3/4" steel plate is phi*Z*Fy where phi is 0.9, Z is the plastic modulus and Fy is the yield point of the material.

Plastic modulus Z = bt[sup]2[/sup]/4 or in this case, 8*(0.75)[sup]2[/sup]/4 = 1.73 in[sup]3[/sup].

For A36 steel, M[sub]factored[/sub] = 0.9*1.73*36 = 56"k or 4.67'k

Accordingly, M[sub]allowable[/sub] = 3.1'k.

BA

 

[dursunlutfu]

@BAretired Thank you for the response. I just wanted to make sure the bending capacity is okay for that connection.

Thanks again for your time!

 

[dursunlutfu]

@amain002

The concrete structure is an existing structure. I am only designing the pergola. I am assuming that the slab is tied to the wall. My loads are not high lateral loads. Anchor bolts meet with the spacing requirements.

Thank you for your time!