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blakenoah
01-03-2012, 04:08 PM
We have to supply an artists technical team with the Kn/m2 (Kilonewton/meter2) of our exhibition floor. I've been able to find definitions and mathematical calculations of Kn/m2, but am still unclear of the physical process of determining Kn/m2 onsite. Will the engineer be bringing an indentor to determine Kn/m2 or are there other methods of calculation?

The building is an old factory that has been refurbished and now houses the museum. Unfortunately, there are no proper records of the building on file to reference in these situations. Welcome to China.

Gallagher
01-09-2012, 07:12 AM
I believe it is a calculation, but never asked the engineer that we use; he does consult the building plans before providing the answer though. I needed to drive a fork lift with a load over a area I was unsure of; I knew there was a slab under the carpet, but I wasn't sure of the thickness, etc, so I brought in the engineer.

Dave

T. Ashley McGrew
01-14-2012, 09:20 AM
I have been waiting for someone to answer this. Obviously the Kn/m2 is just a unit of measure that can be converted into pds per square inch or whatever unit of measure you prefer. How it is determined really should be a question to ask the engineer. Worst case scenario if absolutely nothing is known about the construction of the building it seems to me could include using a core drill to (like a hole saw but for stone) that will remove a rod of the concrete. This gives you two things - direct confirmation of the depth to the pour and a sample to use for testing the strength of the concrete that was used.
The next step could be to use a scanner (the name of which escapes me) that you run over the surface of the concrete in a grid pattern. It will create a picture of whatever reinforcement was used inside the concrete. Both core drilling (for heavy floor anchors) and scanning were relatively common procedures at the Getty so it is not really all that exotic - just part of working in a seismic zone. It was done there to avoid drilling out rebar in the slab (and therefore weakening it).
The only thing I wonder though is that if it is an old building I have heard that in that part of the world bamboo was often used to reinforce concrete. May sound crazy but I am told it was really effective - just not sure if it would show up in a scanner or how accurately engineers can calculate its strength even if it does! Now that we are all curious - please let us know what you turn up.
Regards,

Ashley