OpenSees User Workshop Geotechnical tools
Transcript of OpenSees User Workshop Geotechnical tools
![Page 1: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/1.jpg)
OpenSees User Workshop
Geotechnical tools
Boris Jeremic
Department of Civil and Environmental Engineering
University of California, Davis
Jeremic, Sept. 2004 1
![Page 2: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/2.jpg)
Enabling Technologies Overview
• Object Oriented Framework (OpenSees core, nDarray, )
• Template Elasto–Plasticity
• Full Coupling of Solid and Fluid
• Domain Reduction Method
• Distributed Memory Parallel Computing
• General Large Deformations
• Stochastic Elasto–Plasticity
• Visualization
Jeremic, Sept. 2004 2
![Page 3: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/3.jpg)
Applications Overview
• Template Elasto–Plasticity and Damage (constitutive behavior,
isotropic, kinematic, distortional hardening/softening)
– Small deformations
– Large deformations
• Static behavior of pile–soil systems
– Single piles in layered soils
– Interaction of piles in pile groups
• Wave (synthetic and seismic) propagation in soils (1D – 3D)
– Single phase soils (dry)
– Multiphase phase soils (saturated, coupled fluid–solid)
• Seismic Soil–Foundation–Structure (SFS) Interactions
– Free field motions in 1D, 2D and 3D
– SFS Interaction in 1D, 2D and 3D
Jeremic, Sept. 2004 3
![Page 4: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/4.jpg)
Template Elasto–Plasticity
Yield function (or lack of YF), potential function (and/or flow
directions), hardening/softening laws (scalar, rotational/translational
kinematic, distortional...)
• Independent definitions of:
1. Yield function (and it’s derivatives)
2. Plastic flow direction (first and second derivatives of potential
function)
3. Evolutions laws for the above two
• This is used to create Template Elastic–Plastic Models
Jeremic, Sept. 2004 4
![Page 5: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/5.jpg)
Template Commands
## Yield surfaceset ys "-DP"## Potential surfaceset ps "-DP 0.2"
## Isotropic evolution law:set ES1 "-Leq 0.0"## Kinematic evolution law:set ET1 "-Linear 100.0"
## Elastic modelnDMaterial ElasticIsotropic3D 1 70000.0 0.2 1.8
## EPState_____________alpha___kset EPS "-NOD 1 -NOS 2 0.2 2.0"
## Creating nDMaterial-----MatTag--ElMatTag--nDMaterial Template3Dep 2 1 -YS $ys -PS $ps -EPS $EPS -ELS1 $ES1 -ELT1 $ET1
##_______________tag_____8 nodes________matID__bforce1_bforce2_bforce3_rhoelement Brick8N 1 5 6 7 8 1 2 3 4 2 0.0 0.0 0.0 1.8
Jeremic, Sept. 2004 5
![Page 6: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/6.jpg)
Template Elastic–Plastic Models
• Yield surfaces: von Mises VM, Drucker–Prager DP, Rounded Mohr–
Coulomb RMC, Cam–Clay CC, Parabolic Leon PL, User added (really
easy),
• Plastic flow directions (potential surfaces): von Mises VM, Drucker–
Prager DP, Rounded Mohr–Coulomb RMC, Cam–Clay CC, Manzari–
Dafalias MD, Parabolic Leon PL, User added (really easy),
Jeremic, Sept. 2004 6
![Page 7: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/7.jpg)
Template Elastic–Plastic Models(contd)
• Isotropic and/or kinematic and/or distortional hardening/softening
– linear and/or nonlinear isotropic hardening/softening
– linear or nonlinear kinematic hardening/softening
∗ Armstrong–Fredericks nonlinear kinematic hardening/softening
∗ Bounding surface nonlinear (Dafalias–Popov) kinematic hard-
ening/softening
– User defined distortional hardening
• Hierarchical database of models (by materials)
Jeremic, Sept. 2004 7
![Page 8: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/8.jpg)
3D Solid Elements
Three types of brick elements:
• 8 node brick element Brick8N#_______________tag_____8 nodes_____matID__bforce1_bforce2_bforce3_rho
element Brick8N 1 1 2 3 4 5 6 7 8 1 0.0 0.0 $g $rho
• 20 node brick element Brick20N
• 27 node brick element Brick27N
Jeremic, Sept. 2004 8
![Page 9: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/9.jpg)
Template E-P Examples
• SmallDeformationExamples.tcl
• Pure_Shear_Test.ops
• Triaxial_Test.ops
• Simple_Shear_Test.ops
Jeremic, Sept. 2004 9
![Page 10: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/10.jpg)
Template Examples
0 2 4 6 8 100
5
10
15
20
25
30
35
40
εa (%)
q (k
Pa)
0 2 4 6 8 10−7
−6
−5
−4
−3
−2
−1
0
1
εa (%)
ε v (%
)0 2 4 6 8 10
0
5
10
15
20
25
30
εa (%)
q (k
Pa)
0 2 4 6 8 100
0.1
0.2
0.3
0.4
0.5
εa (%)
ε v (%
)
0 2 4 6 8 100
5
10
15
20
25
30
εa (%)
q (k
Pa)
0 2 4 6 8 100
0.5
1
1.5
2
2.5
3
3.5
εa (%)
ε v (%
)
0 2 4 6 8 100
5
10
15
20
25
30
35
40
εa (%)
q (k
Pa)
0 2 4 6 8 10−1
−0.5
0
0.5
εa (%)
ε v (%
)
0 2 4 6 8 100
50
100
150
200
εa (%)
q (k
Pa)
0 2 4 6 8 100
0.5
1
1.5
2
2.5
3
εa (%)
ε v (%
)
0 5 10 150
10
20
30
40
50
60
εa (%)
q (k
Pa)
0 5 10 15−12
−10
−8
−6
−4
−2
0
2
εa (%)
ε v (%
)
Jeremic, Sept. 2004 10
![Page 11: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/11.jpg)
Template Cyclic Examples
−0.4 −0.2 0 0.2 0.4−10
−5
0
5
10
15
εa (%)
q (k
Pa)
−0.4 −0.2 0 0.2 0.40
0.1
0.2
0.3
0.4
0.5
0.6
0.7
εa (%)
ε v (%
)
−0.4 −0.2 0 0.2 0.4−10
−5
0
5
10
εa (%)
q (k
Pa)
−0.4 −0.2 0 0.2 0.4−0.15
−0.1
−0.05
0
0.05
0.1
0.15
0.2
0.25
εa (%)
ε v (%
)
−0.15 −0.1 −0.05 0 0.05 0.1 0.15−20
−10
0
10
20
30
εa (%)
q (k
Pa)
−0.1 −0.05 0 0.05 0.1 0.15−0.5
0
0.5
1
1.5
2
2.5
3
εa (%)
ε v (%
)
Jeremic, Sept. 2004 11
![Page 12: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/12.jpg)
Winkler Springs (aka PY springs)
uniaxialMaterial PySimple1 matTag? soilType? pult? y50? Cd? <c>
uniaxialMaterial TzSimple1 matTag? tzType? tult? z50? <c>
uniaxialMaterial QzSimple1 matTag? qzType? qult? z50? <suction? c?>
uniaxialMaterial PySimple1 1 1 100 0.01 0.0
element zeroLength 2 2 3 -mat 1 -dir 1
• Type is usually set to 1 for clay and 2 for sand.
• Note that p and pult p are distributed loads [force per length
of pile] in common design equations, but are both loads for this
uniaxialMaterial [i.e., distributed load times the tributary length of
the pile].
Jeremic, Sept. 2004 12
![Page 13: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/13.jpg)
Full Coupling of Solid and Fluid
• General form, full coupling, (currently only small deformations)
• DOFs: uLj → solid displacement pL → fluid pressure ULj → fluid
displacement
• 8 node brick element Brick8N_u_p_U#(28 args)____________tag____8 nodes____matID_bforce1_bforce2_bforce3
porosity alpha solid_density fluid_density
perm_x perm_y perm_z s_bulk_modu f_bulk_modu pressure
element Brick8N_u_p_U 1 5 6 7 8 1 2 3 4 1 0.0 0.0 -9.81
0.8 1.0 1.8 1.0
10e-5 10e-5 10e-5 10e5 10e5 0
• 20 node brick element Brick20N_u_p_U
Jeremic, Sept. 2004 13
![Page 14: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/14.jpg)
Plastic Bowl Loading(aka Domain Reduction Method)
• Based on work by Bielak et al. at CMU.
• Seismic motions and accelerations input at the layer of elements
that encompass an elastic–plastic zone (using SHAKE, Green’s
functions, Quake, SCEC...), non–reflective boundaries• pattern PBowlLoading 1 -pbele "$Dir/PBElements.dat"
-acce "$Dir/Inp_acce.dat" -disp "$Dir/Inp_disp.dat" -dt 0.02-factor 1 -xp 6.0 -xm -6.0 -yp 6.0 -ym -6.0 -zp 0.0 -zm -17.5
Fault
Plastic (Soil) "Bowls"
Jeremic, Sept. 2004 14
![Page 15: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/15.jpg)
General Large DeformationsHyperelasto–Plasticity
• Based on the multiplicative decomposition of the deformation
gradient.
• More general approach (applicable to anisotropic material, cyclic
loading) than current state of the art (based on Simo’s work)
0 2 4 6 8 100
2
4
6
8
10
12
14x 10
6
shear strain γ
σ 13 [P
a]
Neo−HookeanLogarithmicMooney−RivlinOgden
−0.2 −0.1 0 0.1 0.2 0.3 0.4−40
−30
−20
−10
0
10
20
30
40
50
60
Shear Ratio
σ 13 (
kPa)
EP MonotonicEP Cyclic
Jeremic, Sept. 2004 15
![Page 16: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/16.jpg)
Geotechnical Applications
• Constitutive behavior of test specimens
• Behavior of piles in layered soils
• Interactions of piles in pile groups
• Wave propagation in saturated soils
• Seismic behavior of soils and soil-structure interactions (1D and
3D)
Jeremic, Sept. 2004 16
![Page 17: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/17.jpg)
Long Specimen
Progression of plastic zone for a long specimen with high friction
end platens
Jeremic, Sept. 2004 17
![Page 19: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/19.jpg)
Constitutive Response?
0 0.5 1 1.5 2 2.5 30
50
100
150
200
250
300
350
Shear Strain ε (%)
q (k
Pa)
Without Friction − Cubic Sample With Friction − Cubic SampleWithout Friction − 2 to 1 Sample With Friction − 2 to 1 Sample
0 0.5 1 1.5 2 2.5 3 3.534
34.5
35
35.5
36
36.5
37
37.5
38
Max. inclination angle (deg)
Mob
ilize
d fr
ition
ang
le a
t 2.0
% a
xial
str
ain
Actual friction angle: 37.0o
Jeremic, Sept. 2004 19
![Page 20: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/20.jpg)
Single Pile in Layered Soils
−1000 0 1000 2000−10
−8
−6
−4
−2
0
2
SAND
φ = 37.1o
−1.718
SOFT CLAY
Cu = 21.7 kPa
−3.436
SAND
φ = 37.1o
Bending Moment (kN.m)
Dep
th (
m)
SAND
φ = 37.1o
−1.718
SOFT CLAY
Cu = 21.7 kPa
−3.436
SAND
φ = 37.1o
SAND
φ = 37.1o
−1.718
SOFT CLAY
Cu = 21.7 kPa
−3.436
SAND
φ = 37.1o
−400 −200 0 200 400 600−10
−8
−6
−4
−2
0
2
Shear Force (kN)−100 0 100 200 300
−10
−8
−6
−4
−2
0
2
Lateral Resistance (kN/m)−1000 0 1000 2000
−10
−8
−6
−4
−2
0
2
SAND
φ = 37.1o
−1.718
SOFT CLAY
Cu = 21.7 kPa
−3.436
SAND
φ = 37.1o
Bending Moment (kN.m)
Dep
th (
m)
−400 −200 0 200 400 600−10
−8
−6
−4
−2
0
2
Shear Force (kN)−100 0 100 200 300
−10
−8
−6
−4
−2
0
2
Lateral Resistance (kN/m)
Jeremic, Sept. 2004 20
![Page 21: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/21.jpg)
p− y Response for Single Pile inLayered Soils
0 2 4 6 8 10 120
50
100
150
200
250
300
Lateral Displacement y (cm)
Late
ral P
ress
ure
p (k
N/m
)
Depth −0.322Depth −0.537Depth −0.752Depth −0.966Depth −1.181Depth −1.396Depth −1.611Depth −1.825Depth −2.040Depth −2.255Depth −2.470Depth −2.684
0 2 4 6 8 10 120
50
100
150
200
250
300
Lateral Displacement y (cm)La
tera
l Pre
ssur
e p
(kN
/m)
Depth −0.322Depth −0.537Depth −0.752Depth −0.966Depth −1.181Depth −1.396Depth −1.611Depth −1.825Depth −2.040Depth −2.255Depth −2.470Depth −2.684
• Influence of soft layers propagates to stiff layers and vice versa
• Can have significant effects in soils with many layers
Jeremic, Sept. 2004 21
![Page 22: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/22.jpg)
Examples
• Number of example models available at
http://cml00.engr.ucdavis.edu/~guanzhou/NEES_Project/
• Single pile (elastic solid beam or inelastic beam-column) in inelastic
soil (solids)
• Stages of loading (self weight for soil only, static pushover, dynamic
motions (seismic, surface shaker)
Jeremic, Sept. 2004 22
![Page 23: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/23.jpg)
Pile Group Simulations
• 4x3 pile group model and plastic zones
Jeremic, Sept. 2004 23
![Page 24: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/24.jpg)
Out of Plane Effects
• Out-of-loading-plane bending moment diagram,
• Out-of-loading-plane deformation.
Jeremic, Sept. 2004 24
![Page 25: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/25.jpg)
Load Distribution per Pile
0 1 2 3 4 5 6 7 8 9 10 115
6
7
8
9
10
11
12
13
14
15La
tera
l Loa
d D
istr
ibut
ion
in E
ach
Pile
(%
)
Displacement at Pile Group Cap (cm)
Trail Row, Side PileThird Row, Side PileSecond Row, Side PileLead Row, Side PileTrail Row, Middle PileThird Row, Middle PileSecond Row, Middle PileLead Row, Middle Pile
Jeremic, Sept. 2004 25
![Page 26: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/26.jpg)
Piles Interaction at -2.0m
• Note the difference in response curves (cannot scale single pile
response for multiple piles)
Jeremic, Sept. 2004 26
![Page 27: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/27.jpg)
Validation with Centrifuge Tests
0 1 2 3 4 5 6 7 8 9 1015
20
25
30
35
40
45
Late
ral L
oad
dist
ribut
ion
in e
ach
row
(%
)
Lateral Displacement at Pile Group Cap (cm)
FEM − Trail RowFEM − Third RowFEM − Second RowFEM − Lead RowCentrifuge − Trail RowCentrifuge − Third RowCentrifuge − Second RowCentrifuge − Lead Row
Jeremic, Sept. 2004 27
![Page 28: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/28.jpg)
Seismic Wave Propagation Model
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
−27.3
−23.3
−21.8
−18.3
−14.8
−11.8
−8.8
−6.3
−3.3
−1.8
0.0
Time (s)
Acc
eler
atio
n (m
/s2 )
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5−27.3
−23.3
−21.8
−18.3
−14.8
−11.8
−8.8
−6.3
−3.3
−1.8
0.0
Time (s)
Dis
plac
emen
t (m
)
Jeremic, Sept. 2004 28
![Page 29: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/29.jpg)
Seismic Wave PropagationSoft Soil
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
0.0625−27.3
0.0633−23.3
0.0678−21.8
0.0749−18.3
0.0846−14.8
0.0960−11.8
0.1076 −8.8
0.1160 −6.3
0.1208 −3.3
0.1207 −1.8
0.1181 0.0
Max
Time (s)
Dis
plac
emen
t (m
)
Z
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
0.0622−25.0
0.0779−21.0
0.0837−19.5
0.0982−15.0
0.1069−11.0
0.1123 −7.0
0.1169 −4.3
0.1174 −3.6
0.1179 −1.8
0.1181 0.0
0.1183 1.8
0.1178 3.6
0.1173 4.3
0.1129 7.0
0.1075 11.0
0.0984 15.0
0.0837 19.5
0.0779 21.0
0.0622 25.0
Max
Time (s)
Dis
pala
cem
ent (
m)
Y
Jeremic, Sept. 2004 29
![Page 30: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/30.jpg)
Seismic Wave PropagationStiff Soil
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
0.0625−27.3
0.0658−23.3
0.0724−21.8
0.0735−18.3
0.0745−14.8
0.0753−11.8
0.0758 −8.8
0.0761 −6.3
0.0762 −3.3
0.0762 −1.8
0.0760 0.0
Max
Time (s)
Dis
plac
emen
t (m
)
Z
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
0.0622−25.0
0.0715−21.0
0.0727−19.5
0.0737−15.0
0.0746−11.0
0.0754 −7.0
0.0759 −4.3
0.0759 −3.6
0.0760 −1.8
0.0760 0.0
0.0760 1.8
0.0759 3.6
0.0758 4.3
0.0754 7.0
0.0746 11.0
0.0737 15.0
0.0726 19.5
0.0715 21.0
0.0622 25.0
Max
Time (s)
Dis
plac
emen
t (m
)
Y
Jeremic, Sept. 2004 30
![Page 31: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/31.jpg)
SSI Model: Seismic Results
0 5 10 15 20 25 30 35 40
0.0000−38.0
0.0077−30.0
0.0783−28.0
0.0791−20.0
0.0844−16.0
0.0878−12.0
0.1248 −8.0
0.1800 −4.0
0.1946 0.0
Time (s)
Dis
plac
emen
t (m
)
Z(m) Max
0 5 10 15 20 25 30 35 40
0.0000−38.0
0.0224−30.0
0.0879−28.0
0.1102−20.0
0.1161−16.0
0.1227−12.0
0.3961 −8.0
0.6258 −4.0
0.6928 0.0
Time (s)
Dis
plac
emen
t (m
)
Z(m) Max
Stiff soil Soft soil
Jeremic, Sept. 2004 31
![Page 32: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/32.jpg)
DRM Model Analysis
• Self–equilibrating forces (almost) acting on a layer of element
• Dynamically equivalent to the far field dynamic excitation
• Externally radiating motions come from the structure
• examples available at
http://sokocalo.engr.ucdavis.edu/~jeremic/CG/Examples/SoilFoundationStructureInteraction/3D/
Jeremic, Sept. 2004 32
![Page 34: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/34.jpg)
1D Model (Verification Study)
• 1D model used for validation
• Vertically propagating shear wave
• Used both closed form and numerical
solutions for generating DRM forces
• Calibration springs used to model
support of soils on the side
• Outgoing waves represent the dynamic
characteristic of structure
• tested using harmonic and
fling (pulse) motions
• examples available at
http://sokocalo.engr.ucdavis.edu/~jeremic/CG/Examples/SoilFoundationStructureInteraction/1D/
Jeremic, Sept. 2004 34
![Page 35: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/35.jpg)
Comparing Free Field and SFSI
0 2 4 6−0.014
−0.012
−0.01
−0.008
−0.006
−0.004
−0.002
0
Time [s]
x−D
isp.
[m]
Base, z = −13 m
0 2 4 6−0.03
−0.02
−0.01
0
0.01
0.02
0.03
Time [s]
x−D
isp.
[m]
Exterior domain, z = −9 m
0 2 4 6−0.03
−0.02
−0.01
0
0.01
0.02
0.03
Time [s]
x−D
isp.
[m]
Exterior node of boundary layer
0 2 4 6−0.5
0
0.5
1
Time [s]
x−D
isp.
[m]
Interior node of boundary layer
0 2 4 6−0.5
0
0.5
1
1.5
Time [s]
x−D
isp.
[m]
Interior domain, z = −3 m
0 2 4 6−0.5
0
0.5
1
1.5
2
Time [s]
x−D
isp.
[m]
Surface
DRM with Fixed BaseDRM with Absorbing Boundary
1D soil column subject to pulseFree−Field, effective forces obtained from large free−field model
0 2 4 6−0.5
0
0.5
Time [s]
x−D
isp.
[m]
Base, z = −13 m
0 2 4 6−0.5
0
0.5
Time [s]
x−D
isp.
[m]
Exterior domain, z = −9 m
0 2 4 6−1
−0.5
0
0.5
1
Time [s]
x−D
isp.
[m]
Exterior node of boundary layer
0 2 4 6−1
−0.5
0
0.5
1
Time [s]
x−D
isp.
[m]
Interior node of boundary layer
0 2 4 6−1
−0.5
0
0.5
1
1.5
Time [s]
x−D
isp.
[m]
Interior domain, z = −3 m
0 2 4 6−1
−0.5
0
0.5
1
1.5
2
Time [s]
x−D
isp.
[m]
Surface
DRM with Fixed BaseDRM with Absorbing Boundary
1D soil column subject to pulseAdded structure, effective forces obtained from large free−field model
Jeremic, Sept. 2004 35
![Page 36: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/36.jpg)
Parametric Study: FF and SFSI
• Site amplification for harmonic motions
• Significant change of FF motions in presence of structure
• Can (should) be used in estimating optimal design for given type
of earthquake
Jeremic, Sept. 2004 36
![Page 37: OpenSees User Workshop Geotechnical tools](https://reader030.fdocuments.us/reader030/viewer/2022012721/61b3e3fa75292f490c0410f5/html5/thumbnails/37.jpg)
Conclusions
• Lecture notes (work in progress)
http://sokocalo.engr.ucdavis.edu/~jeremic/CG/CompGeomechanicsLectureNotes.pdf
• Examples
http://sokocalo.engr.ucdavis.edu/~jeremic/CG/Examples
• Applications/Examples Web Portal
http://sokocalo.engr.ucdavis.edu/~jeremic/CG/Portal
• Fresh executables (Linux, MS Windows)
http://sokocalo.engr.ucdavis.edu/~jeremic/OpenSees/EXECUTABLES
• Questions, comments (once you digest all of this):
Jeremic, Sept. 2004 37