How to model the soil
How to model the soil
(OP)
I am designing a water retaining structure and I need to know how to model the soil under the structure to see the soil stresses. pl help me on this regards.
Thanks you in advance
Thanks you in advance





RE: How to model the soil
but there is no harm if you do a little theory yourself. You can APPROXIMATE soil by using springs.
The value of spring you should input into SAP2000 is calculated as follows
1-Determine the soil stiffness in kN/m3 or ton/m3 of lbs/ft3 whatever units
2-Multiply this by the area represented by the node where you want to put the spring, this gives you kN/m or ton/m or lbs/ft etc.
This is really a crude approximation and you wont get results more superior than you would get doing some manual calculations.
And there is a trap. If your spring reactions are negative, the model becomes wrong. Make sure you dont have spring reactions with uplift, since real soil can not tolerate that
And another trap: If your loads are seismic, spring stiffness determined above is questionable.
What elements will you use to model the tank? shell elements?
respects
ijr
RE: How to model the soil
It is really helpful and as you said I need to study some text book. Yes, I have used shell element to model the Intze type tank. Anyway I have some questions on this regards and hope to come back soon. I hope you will help me again.
With Regards
Lasa
RE: How to model the soil
RE: How to model the soil
I have recently encountered a similar problem with yours, modeling the soil in order to find out the stresses, and I did it using solids. I assigned the appropriate material properties to the solids and i was able to see the stress distribution after the analysis.
I might add it's a bit time consuming and I am still in the process of validating this approach.
Cheers,
iotoma