Modulus of Sub-Grade Reaction

[PEinVA]

I was given a value of 150 KCF for my modulus of sub-grade reaction.

I've posted about this before, but could anyone give me some guidance?

How does this convert for a 20'x16' combined footing with 2'x2' panels?
Please let me know ASAP.

thanks.

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[Lion06]

I am getting that it should come out to 50K/in for each 2'x2' panel

 

[PEinVA]

Is that just using 87 psi * (24"x24")? to get 50K/in?


Isn't there a formula to modify this based on the size of the footing?

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[Lion06]

I don't know where your 87psi came from, but what I did is this:
The 150 KCF is 150ksf per foot. Multiply that by the panel siae of 4sq ft to get 600 K/ft, then divide by 12"per ft to get 50 K/in.

 

[Lion06]

I don't know where your 87psi came from, but what I did is this:
The 150 KCF is 150ksf per foot. Multiply that by the panel size of 4sq ft to get 600 K/ft, then divide by 12" per ft to get 50 K/in.

 

[PEinVA]

87 psi is = 150 kcf ---> 150,000/12/144 = 86.81 psi

86.81 psi * 24"x24" = 50 kips/in

we just went about it using different starting points. Sorry for not making the 87psi clear. All examples I've seen use psi as the units so I wanted to be consistent with that.

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[PEinVA]

Isn't there a formula to reduce the modulus first K*1/B then K*(1+0.5(B/L))/1.5?

When does this apply?

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke