Testing of concrete slab

[mateogrin]

I have an existing building and no accurate structural drawings from the time it was built (mid 1960s). I am looking to find out the f'c of the slab, but the slab is only 3" thick, which means for very squat test samples. Is there a way to test the concrete to find the f'c with samples that are so small?


Also, I'm looking to find the f'm for existing masonry in the same building. Are there tests out there to take an existing block and find its f'm?

Thanks for any help you can give me.

M

 

[mitchelon]

Wow, 1960s. Is it a slab on grade? Try non-destructive analyzes if a core sample will not be long enough.

 

[henri2]

For core diameter check ASTM C 42 Sec 7.1.

What is the nominal max size aggregate of mix...any idea?

For f'm refer to IBC Sec 2105.3-Testing prisms from constructed masonry

 

[civilperson]

Hire a testing lab with a Swedish Impact Hammer. Calibrate the hammer on test cylinders of differing compressive strengths and then compare the slab results.(+/- 10%)