Concrete pad foundation design

[stevelovetowork]

I'm looking to design a concrete pad foundation - the information I'm given is the shear strength, kPa and I'm not sure of how to convert this to bearing capacity (or whether I need to). Any help is appreciated, I need to start with something.

 

[stevelovetowork]

I also want to add, the shear strength I'm given is from the borehole report. This varies depending on the depth of the soil obviously so I'm also unsure of which value to use? Should I be using worst case scenario or use the value at which my foundation will be sitting?

 

[oldestguy]

If the test borings were done by a firm which had on board an engineer with the geotech specialty, I'd ask that person. I don't normally see that test borings provide shear strength; perhaps unconfined compressive strength or maybe angle of friction, but not shear strength. Suppose excessive settlement will control the design, in which case shear strength won't be sufficient info.

 

[msquared48]

It is not your responsibility to determine that. Ask the Geotech

Mike McCann, PE, SE (WA)

 

[Ron]

More info please! Are you designing a concrete pad for equipment support? Will the equipment be static or dynamic (rotating/vibrating)? What is the size of the pad? What are the soil conditions down to twice the foundation width? Do you really need a foundation or just a concrete pad supported by surface soils? Is there erosion potential from cross-flow surface drainage?