OCTAVE KD4kvmb.m - Kelvin-Voigt (KV) to Hydraulic Conductivity (Kd) Plot
KD4kvmb prompts for:
Frequency (Hz)
(GUI Entry Box)
Porosity (n)
C1 shear wave determined stiffness (m^2/s^2)
C2 shear wave determined damping (m^2/s)
C1 standard deviation
C2 standard deviation
Porosity standard deviation
Basic Seismic Utilities (BSU) program run in Octave or Matlab. Within an octave session, type KD4kvmb and a GUI pops up as shown above. The mapping between the KVMB and KV constitutive representations depends on pore diameter, porosity, frequency, and viscosity of fluid. Examine the code for assumptions. This is an inversion solution that relates porosity and shear wave down hole transmission measurements of wave dispersion and amplitude decay (which are inverted for C1 and C2 viscoelastic shear wave equation coefficients) to hydraulic conductivity. There will be either one, two, or no solutions. The curve relating effective damping ratio (computed from C1,C2, and n) to hydraulic conductivity is concave down with respect to damping ratio. Thus, a horizontal line drawn for a constant KV damping ratio will intersect the concave down curve in two points if the damping ratio (DR) is less than the peak of the curve. These are the coupled and uncoupled fluid frame to water solutions. While unlikely, it is possible that the DR curve will intersect the peak at one point. Finally, if the wave measurements yield a DR that is above the peak, there will be no solution. Bump. Reference: Michaels (2006) "Relating Damping to Soil Permeability" Vol. 6, No. 3, International Journal of Geomechanics, ASCE p. 158-165.
GUI entry box as given above.
Solutions for hydraulic conductivity and 95 % confidence interval (msgbox and text window)
bvas(1) bamp(1) caplot3.m(7) kvKVMBscan.m(7) fqKVMBscan.m(7) kdKVMBscan.m(7)
No known bugs.
Copyright © 2017 by Paul Michaels
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
P. Michaels, PE. <pm@cgiss.boisestate.edu>