Assigning zone properties from boreholes like SPT, CPT, etc. for creating own 3D soil layers

FLAC3D
1

Can anyone give me idea as to how I can import my borehole data in terms of X,Y,Z, and Nspt or qt, fs, or u2 or any other data to assign to the zones. So that I can calculate the material parameters using empirical correlations? I want to create variable layers of soils in 3D from their interpolation. Can anyone help?

2

A good way is to use Python to do the job.
Below is a small example to interpolate pore-pressures to the gridpoints (It is similar to interpolate other parameters to zones).

  1. Make sure the source datafile format is correct. It is simply the coordinates and data value each line (x, y, z, data). See data.txt (288.2 KB)

  2. Make sure the background grid is in the model (run model.dat (545 Bytes) in FLAC3D)

  3. Run the Python scripts in FLAC3D below (e.g., copy them into a file like “inter.py” and run):

import itasca as it
from itasca import gridpointarray as gpa
import numpy as np
from scipy.interpolate import griddata
 
data = np.loadtxt("data.txt")
pos,pp = data[:,:3],data[:,3]
gp_pp = griddata(pos,pp,gpa.pos())
gpa.set_porepressure(gp_pp)

The final results would be:

inter_pp
inter_pp1920Ă—931 455 KB

where the dots are source data, the contours are the interpolated data.

1 Like
3

Thankyou so much. I tried importing CPT values onto the grid points using this method.It worked greatly. How do I convert the gridpoint values to the zone properties after that?

4

You then need to use zone-related Python API. For example, if you wish to interpolate bulk moduli to zones (I assume you have bulk modulus data (as in “data.txt”) using some calibration method from CPT or SPT, et al) . Run this example below (just a demo example so I use the same source data):

import itasca as it
from itasca import zonearray as za
from scipy.interpolate import griddata

data = np.loadtxt("data.txt")
pos,pp = data[:,:3],data[:,3]
z_bulk = griddata(pos,pp,za.pos())
za.set_prop_scalar("bulk",  -z_bulk)

The result would be

bulk
bulk3800Ă—1843 307 KB

Please refer to the documentation for different cases with necessary modifications.

5

Thankyou so much. I am really grateful for your support. I will try using it.