Data Files for “Shallow Foundation” Tutorial

Footing.p3dat

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; fname: Footing.p3dat
;
;  Create a balls assembly and install a shallow foundation
;==============================================================================

model new

;Set the domain extent and condition
model domain extent (-1,25) (-6,6) (-6,20)
model domain condition destroy

;generate a box and a cloud of 2000 equally sized balls
wall generate box (0,24) (-5,5) (0,17)
model random 10001
ball generate box (0,24) (-5,5) (0,10) number 2000 radius 0.40   

; Modify the default slots of the Contact Model Assignement Table
; Here we choose the linear contact model (with kn=1e8) for all contact types
; but ball-ball contacts, to which we assign the linearpbond model. Note that
; only the linear part of the linearpbond model is activated as long as the 
; contact method bond is not called, which is done later
contact cmat default type ball-ball model linearpbond ...
        property fric 0.577 kn 1e8 ks 1e8             ...
        pb_kn 1e8 pb_ks 1e8 pb_ten 1e6                ...
        pb_coh 1e6 pb_rmul 0.8 dp_nratio 0.2

contact cmat default type ball-facet model linear     ...
        property fric 0.09 kn 1e8 ks 1e8              ...
        dp_nratio 0.2

;define the density and increase their radii
ball attribute density 2000 radius multiply 1.4

;define some history to plot the velocity of a ball of the assembly and 
;of the unbalanced force. Histories are stored each 5 cycles.
history interval 5
ball history velocity-z position 12 0 5
model history mechanical unbalanced-maximum

; To reach a stable configuration faster, density scaling is activated.
; Gravity is introduced
model mechanical timestep scale
model gravity 0 0 -9.81
model cycle 1000 calm 50
model solve ratio-average 1e-5

; creation of a box-shaped foundation
; the name 'footing' is associated to the respective group of walls
wall delete range set id 2
wall generate group 'footing' box (0,5) (-5,5) (12,20) 


; parallel bonds are finally installed. LinearPBond model is active
; for ball-ball contacts. The simulation is saved at this stage
; so that further restoring is possible
contact method bond gap 0.0

model save 'Assembly'

; The foundation is supposed to settle with a constant velocity
; The contact force at the foundation's base is stored during the simulation
wall attribute velocity-z -0.25 range group 'footing'
history wall force-contact-z id 7

; The timestep is set to its automatic value for dynamic simulations and an
; additional 5 seconds are simulated. The model is saved at the end.
model mechanical timestep auto
model solve time 10.0

; Solve to an equilibrium state again
wall attribute velocity-z 0.0
model solve ratio-average 1e-5

model save 'Footing'

;==============================================================================
; eof: Footing.p3dat
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Tunnel.p3dat

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; fname: Tunnel.p3dat
;
;  Excavation of an unsupported tunnel
;==============================================================================

; The state prior to the footing load is restored
model restore 'Assembly'

; A cylinder-shaped tunnel is excavated through the 'delete' 
; and the 'range group' commands
ball group 'Tunnel' range cylinder end-1 (16.0,-6.0,6.0) ...
     end-2 (16.0,6.0,6.0) radius 3.0
ball delete range group 'Tunnel'

; A number of cycles are done in order to verify that the model is stable 
; after excavation of the tunnel. The model is saved at this stage.
model cycle 1
model solve ratio-average 1e-5

model save 'StableTunnel'

;The assembly is finally loaded by the footing. What happens to the tunnel?
wall attribute velocity-z -0.25 range group 'footing'

model mechanical timestep auto
model solve time 10.0

; Solve to an equilibrium state again
wall attribute velocity-z 0.0
model solve ratio-average 1e-5


model save 'UnlinedTunnel'

;==============================================================================
; eof: Tunnel.p3dat
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Lining.p3dat

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; fname: Lining.p3dat
;
;  Installation of a lining support for the tunnel
;==============================================================================

model restore 'StableTunnel'

; A lining support is installed around the excavation by specifying a higher 
; cohesion and tensile strength to contacts around the Tunnel.

; A group of contacts named 'Lining' is created
contact group 'Lining' range cylinder end-1 (16.0,-6.0,6.0) ...
        end-2 (16.0,6.0,6.0) radius 4.0

; A new set of properties is defined for the contacts of the group 'Lining'
contact property fric 0.18 kn 1e8 ks 1e8            ...
        pb_kn 1e8 pb_ks 1e8 pb_ten 1e10             ...
        pb_coh 1e10 pb_rmul 1.0 dp_nratio 0.2       ...
        range group 'Lining'

; The assembly is loaded again by the footing. Which differences with respect
; to the case of the unlined tunnel?
wall attribute velocity-z -0.25 range group 'footing'

model save 'Lining'

model mechanical timestep auto
model solve time 10.0

; Solve to an equilibrium state again
wall attribute velocity-z 0.0
model solve ratio-average 1e-5

model save 'LinedTunnel'

;==============================================================================
; eof: Lining.p3dat
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Footing.p2dat

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; fname: Footing.p2dat
;
;  Create an assembly and install a shallow foundation
;==============================================================================

model new

;Set the domain extent and condition
model domain extent (-1,25) (-6,20)
model domain condition destroy

;generate a box and a cloud of 2000 equally sized balls
wall generate box (0,24) (0,17)
model random 10001
ball generate box (0,24) (0,10) number 2000 radius 0.1250

; Modify the default slots of the Contact Model Assignement Table
; Here we choose the linear contact model (with kn=1e6) for all contact types
; but ball-ball contacts, to which we assign the linearpbond model.
; Note that only the linear part of the linearpbond model is activated as long
; as the contact method bond is not called, which is done later
contact cmat default type ball-ball model linearpbond   ...
        property fric 0.577 kn 1e8 ks 1e8       ...
        pb_kn 1e8 pb_ks 1e8 pb_ten 1e6          ...
        pb_coh 1e6 pb_rmul 0.8 dp_nratio 0.2

contact cmat default type ball-facet model linear       ...
    property kn 1e8 ks 1e8 fric 0.09            ...
    dp_nratio 0.2

;define the density of the balls and increase their radius
ball attribute density 2000 radius multiply 1.4

;define some history to plot the velocity of a ball of the assembly and 
;of the unbalanced force. Histories are stored each 5 cycles.
history interval 5
ball history velocity-y position 12 5
model history mechanical unbalanced-maximum

; To reach a stable configuration faster, density scaling is activated.
; Gravity is introduced
model mechanical timestep scale
model gravity 0 -9.81
model cycle 1000 calm 50
model solve ratio-average 1e-5

; creation of a box-shaped foundation
; the name 'footing' is associated to the respective group of walls
wall delete range set id 3
wall generate group 'footing' box (0,5) (11,20)

; parallel bonds are finally installed. LinearPBond model is active
; for ball-ball contacts. The simulation is saved at this stage
; so that further restoring is possible
contact method bond gap 0.0

model save 'Assembly'

; The foundation is supposed to settle with a constant velocity
; The contact force at the foundation's base is stored during the simulation
wall attribute velocity-y -0.25 range group 'footing'
history wall force-contact-y id 7

; The timestep is set to its automatic value for dynamic simulations and
; an additional 5 seconds are simulated. The model is saved at the end.
model mechanical timestep auto
model solve time 10.0

; Solve to an equilibrium state again
wall attribute velocity-y 0.0
model solve ratio-average 1e-5

model save 'Footing'

;==============================================================================
; eof: Footing.p2dat
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Tunnel.p2dat

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; fname: Tunnel.p2dat
;
;  Excavation of an unsupported tunnel
;==============================================================================

; The state prior to the footing load is restored
model restore 'Assembly'

ball group 'Tunnel' range circle center 16.0 5.0 radius 3.0
ball delete range group 'Tunnel'

; A number of cycles are done in order to verify that the model is stable
; after excavation of the tunnel. The model is saved at this stage.
model cycle 1
model solve ratio-average 1e-4

model save 'StableTunnel'

;The assembly is finally loaded by the footing. What happens to the tunnel?
wall attribute velocity-y -0.25 range group 'footing'

model mechanical timestep auto
model solve mechanical time 10.0

; Solve to an equilibrium state again
wall attribute velocity-y 0.0
model solve ratio-average 1e-4


model save 'UnlinedTunnel'

;==============================================================================
; eof: Tunnel.p2dat
Top

Lining.p2dat

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; fname: Lining.p3dat
;
;  Installation of a lining support for the tunnel
;==============================================================================
model restore 'StableTunnel'

contact group 'Lining' range circle center 16.0 5.0 radius 4.0

contact property fric 0.18 kn 1e8 ks 1e8        ...
        pb_kn 1e8 pb_ks 1e8 pb_ten 1e10         ...
        pb_coh 1e10 pb_rmul 1.0 dp_nratio 0.2   ...
        range group 'Lining'

wall attribute velocity-y -0.25 range group 'footing'

model save 'Lining'

model mechanical timestep auto
model solve time 10.0

wall attribute velocity-y 0.0
model solve ratio-average 1e-4

model save 'LinedTunnel'

;==============================================================================
; eof: Lining.p2dat
Top