Reshoring Jack Capacity 1

[Struct123ure]

Hello,

Concrete high rise has reshoring jacks used for reshoring slabs. Jack capacity is specified with a safety factor of 3:1. I am designing using LRFD, so I am comparing SLS slab load above to the working jack capacity and the ULS slab load to the 3x(Working Jack Capacity)?

 

[Italo01]

I didn't understand the question.

 

[Lomarandil]

Comparing the SLS slab load to the working jack capacity (3:1 FoS) is correct.

Comparing the ULS slab load to the nominal jack capacity (1.0 FoS) is not correct. A resistance (material reduction) factor would need to be applied, and is likely undefined.

You can run through the exercise of getting a reduction factor for the reshoring jack from the manufacturer. Or you can just perform your reshoring calcs using ASD/SLS.