LI Changsheng, YIN Hongwei*, et al. (2021) Calibration of the discrete element method and modelling of shortening experiments. Front. Earth Sci. doi: 10.3389/feart.2021.636512

Original Research: The discrete element method (DEM) is becoming widely accepted as an effective method of addressing tectonic problems in granular materials. It is capable of reproducing structures observed in the analogue model (AM). However, the previous experiments …

Accepted on 05 May 2021

evolutionary process

Unit (cm)

Tectonic evolution process(DEM)

The first one is deformation for the AM. The second is deformation for the DEM. The third is the distortional strain field for the DEM. The shear strain magnitude is shown by color intensity. Red denotes top to the right sense of shear, and blue denotes top to the left sense of shear.

ZDEM script:

  1. Generate. ex8_dem_am_gen.py ：

    ######################################
# title: 离散元数值模拟与构造物理模拟对比试验:1 沉积
# date: 2021-05-16
# authors: 李长圣
# E-mail: sheng0619@163.com
# ref: Li et al. (2021) Calibration of the discrete element method and modelling of shortening experiments. Front. Earth Sci. doi: 10.3389/feart.2021.636512
# more info, see www.geovbox.com
#######################################
start
set disk hex
BOX left 0.5e-3 right 615.0e-3 bottom 0.5e-3 height 160.0e-3 kn=1.5e4 ks=1.5e4 fric 0.3 

wall id 4, nodes (     5e-3  158.0e-3) (  5.0e-3     5.0e-3), kn= 1.5e4 ks= 1.5e4 fric 0.0 
wall id 5, nodes (     5e-3    5.0e-3) (605.0e-3     5.0e-3), kn= 1.5e4 ks= 1.5e4 fric 0.0 
wall id 6, nodes ( 605.0e-3    5.0e-3) (605.0e-3   158.0e-3), kn= 1.5e4 ks= 1.5e4 fric 0.0 

gen grid idmin 0 rad discrete 0.1e-3 0.1e-3 0.2e-3 0.2e-3 0.25e-3 0.3e-3,  x (5.0e-3,  605.0e-3), y (5.0e-3, 155.0e-3), GROUP ball_rand 

PROP color red den 1.3e3, fric 0.0, kn  1.5e4, ks  1.5e4 damp 0.4
FIX spin

SET frac 0.4
SET GRAVITY ( 0.0,  -10.0 )
SET  stepbar 1000
SET  save  20000
SET  print 20000
SET  ps    20000
HIST ID 1 INTERVAL 1000 , kinetic
HIST ID 2 INTERVAL 1000 , step
PLOT hist 2 1

CYC 60000
DEL range x (4.0e-3, 606.0e-3), y (30.0e-3, 1.0),
CYC 20000
#save 2del.sav
EXP ini_xyr.dat
STOP

  2. Push. ex8_dem_am_push.py ：

    ######################################
# title: 离散元数值模拟与构造物理模拟对比试验:2 挤压
# date: 2021-05-16
# authors: 李长圣
# E-mail: sheng0619@163.com
# ref: Li et al. (2021) Calibration of the discrete element method and modelling of shortening experiments. Front. Earth Sci. doi: 10.3389/feart.2021.636512
# more info, see www.geovbox.com
#######################################
LOAD  ini_xyr.dat
SET disk hex
BOX left 0.5e-3 right 615.0e-3 bottom 0.5e-3 height 110.0e-3 kn=1.5e4 ks=1.5e4 fric 0.3 

WALL id 4, nodes (     5e-3  110.0e-3) (  5.0e-3     5.0e-3), kn= 1.5e4 ks= 1.5e4 fric 0.0 
WALL id 5, nodes (     5e-3    5.0e-3) (605.0e-3     5.0e-3), kn= 1.5e4 ks= 1.5e4 fric 0.0 
WALL id 6, nodes ( 605.0e-3    5.0e-3) (605.0e-3   110.0e-3), kn= 1.5e4 ks= 1.5e4 fric 0.0 

PROP color red den 1.3e3, fric 0.0, kn  1.5e4, ks  1.5e4 damp 0.0
FIX spin

SET frac 0.4
SET GRAVITY ( 0.0,  -10.0 )
SET  stepbar 10000
HIST ID 1 INTERVAL 1000 , kinetic
HIST ID 2 INTERVAL 1000 , step
PLOT  2 1

SET damp lsm 0.04
PROP fric 0.30 
PROP color lg
PROP color  red , range x 0.0  615.0e-3 y   9.0e-3  10.0e-3  
PROP color  blue, range x 0.0  615.0e-3 y  14.0e-3  15.0e-3  
PROP color  red , range x 0.0  615.0e-3 y  19.0e-3  20.0e-3  
PROP color  blue, range x 0.0  615.0e-3 y  24.0e-3  25.0e-3  
PROP color  red , range x 0.0  615.0e-3 y  29.0e-3  30.0e-3  

wall id 4 fric 0.30 xv 40e-3
wall id 5 fric 0.30
wall id 6 fric 0.30

CYC 1
imple wall id 4 xmove 160e-3 save 20e-3 print 10e-3 ps 10e-3  vtk 10e-3
stop

The quantitative method of the thrust wedge based on mesh (Data)

Download：analog model.7z

The images of the analog model.