cross bracing - steel and masonry

[tolind]

I'm looking at a situation I don't agree with and want some second opinions. We were contracted to design a mezzanine inside a pre-engineered warehouse building and a attached office. There is a masonry wall with it's centerline hitting the back edge of Their columns. They are now telling me that they want their cross bracing to attach to my masonry wall at a point right next to the column instead of directly to the column. It's an 8 Kip load applied by a rod.

I explained that since we were already Chipping the block around the column we might as well chip around the cross bracing also. They insist on bearing on the block and say it's my problem.

1. Does this seem like the pre-engineering company trying to pawn work off onto me?
2. Does anyone know of a good reference that could help explain how to desing for a situation of this nature?
I know I'l have to grout the block that I attached the connection to but I don't have any idea how to determine a lateral force in the direction of the wall.

 

[Lutfi]

I would say that the PEMB designers should provide complete lateral support for their building via tension bracing. It is normal delegate the design of the PEMB system by the engineer of record. They the engineer of record would design the foundations based on the reactions supplied by the PEMB supplier.

To be honest, I have not seen a situation where the PEMB supplier is asking the CMU designer to take the lateral load of their building unless the wall is a shear wall and is integral part of the PEMB.

This is my two cents worth.

Regards,


Lutfi

http://www.cdeco.com

 

[SperlingPE]

Because of other constraints, I have designed masonry shear walls for PEMB. These were pseudo design build situations, so I was communicating with the PEMB engineers up front. PEMB engineers x-braced down to a certain elevation. PEMB engineers designed the connection to the masonry wall (with my approval) and supplied loads to wall. I have never heard of PEMB engineers asking the EOR to use a masonry wall. Unless there is a very good reason to do this, the PEMB should be a stand alone system.