Modelling a Retaining Wall with a Soil Pressure

bailey_rowland

Would anyone be able to help me with modelling a retaining wall with a soil pressure.

Victor

Could you be a bit more specific?

You can model soil pressure that varies with depth by entering a formula in the pressure load.

For self-weight, add a gravity load and specify density in the material properties.

Use Nonlinear Static 3D analysis type for large rotation that moves the center of gravity or linear Static 3D to neglect that.

Mishal

If the geometry is simplistic, meaning that it is a basic retaining wall without any curves and/or funny geometry, you can then just model it using 2D using beam elements of unit length. With a little post processing you will be able to get the results in a manner such that you can use appropriate concrete design codes.

wolland

See below my formulas for lateral soil pressure (based on AS 5100.2:2017, Clause 14.2 - Surcharge loads from road traffic):

I used in this example an overall '1.7' factor of safety for the 1m of fill as an equivalent for the surcharge load. You can change the formula to suit your needs.

Top of soil at 0.00. 'z' direction is negative ( under the x,y,z = 0,0,0 ). From the first formula below, at the surface level you will have 17 (kPa). Coefficient of earth pressure at rest is assumed to be 0.5. So:

1. soil pressure between 0 - 3m deep: 1.7*(10+tan(atan10)*(0-z)) or : 17*(1-z)
2. soil pressure between 3 - 8m deep: 1.7*(2*(8-abs(z))+tan(atan10)*(0-z)) or: 1.7*(2*(8-abs(z))-10*z)
3. soil pressure between 8 - 10m deep: 1.7*(tan(atan10)*(0-z)) or: -17*z

See the attached file to see how they work. I used 'Temperature' feature in order to visually check the values.

Hope it makes sense.

Cheers!
wolland