Note: Descriptions are shown in the official language in which they were submitted.
AN AUXILIARY DEVICE AND A METHOD FOR MAKING A 3D
PRINTED TUNNEL MODEL
FIELD OF THE INVENTION
[0001] The present application relates to the technical field of geotechnical
engineering testing,
and in particular, to an auxiliary device and a method for making a 3D printed
tunnel model.
DESCRIPTION OF RELATED ART
[0002] Rock masses often contain complex internal structural features, such as
criss-crossing
joint fissures, and holes of different shapes and sizes. These defects
directly affect the
deformation and strength of the entire rock mass, and are directly related to
the stability of rock
mass engineering. Indoor physical model experiments are traditionally used in
order to study the
macro-mechanical properties and deformation failure characteristics of rock
masses containing
artificial structures. However, in the process of numerical simulation of
traditional indoor
physical simulation experiments, the complex engineering rock mass structure
is often simplified,
resulting in a large deviation between the model and the real rock mass.
[0003] With the development of 3D printing technology, researchers have
printed a model
having same internal void characteristics as sandstone from plastics by
adopting the combination
of CT imaging technology and 3D printing technology. However, the materials of
plastic and
rock mass are very different, resulting in the experimental simulation data
being less consistent
with the actual project. Later, the researchers used gypsum to replace
plastics, and printed a
physical model of the gypsum material for testing, and the effect was greatly
improved.
[0004] In the above related technologies, there exists the following defects:
as to the physical
model in the form of a tunnel, the tunnel opening is small after 3D printing,
and the human hand
cannot reach into the tunnel opening to insert the anchor rod, so the model
without anchor rod is
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tested. However, there is anchor rod for supporting in the actual project, so
there is still a
deviation between the simulated data and the actual situation of the project.
BRIEF SUMMARY OF THE INVENTION
[0005] In order to solve the problem that the simulation data of the 3D
printed rock mass
physical model test is less consistent with the actual project, the present
application provides an
auxiliary device and a method for making a 3D printed tunnel model.
[0006] In the first aspect, the present application provides an auxiliary
device for making a 3D
printed tunnel model by adopting the following technical solutions:
An auxiliary device for making a 3D printed tunnel model, including a main rod
and an anchor
insertion mechanism that can extend into a tunnel opening of a physical model,
wherein the
anchor insertion mechanism comprises a feed assembly and a power assembly
installed on the
main rod; the feed assembly comprises a fixed member fixed on the main rod and
a rotating
member rotatably arranged; the power assembly is configured to drive the
rotating member to
rotate; a surface of an anchor rod is defined with a slot in an axial
direction; the rotating member
is in threaded connection with the anchor rod; the fixed member is provided
with a perforation
for the anchor rod to pass through; the perforation is coaxial with a screw
hole on the rotating
member; and the fixed member is provided with a limiting ridge cooperating
with the slot in the
anchor rod to limit the circumferential rotation of the anchor rod.
[0007] By adopting the above technical solution, the anchor rod is firstly
passed through the
perforation of the fixed member outside the physical model, so that the slot
in the anchor rod is
aligned with the limiting ridge in the fixed member, and an end of the anchor
rod extends into
the rotating member; the end of the anchor rod to be flush with the end of the
perforation of fixed
member or to protrude a small section by rotating the rotating member. Then,
the feed assembly
and the anchor rod are inserted into the tunnel opening of the physical model
via the main rod.
When the anchor rod is moved to align with the anchor hole in the physical
model, the rotating
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member is driven to rotate by the power assembly. Due to the screwed
connection between the
anchor rod and the rotating member, and the circumferential rotation of the
anchor rod is
restricted by the limiting ridge, so that the anchor rod is directionally
moved along the
perforation axis and inserted into the anchor hole of the physical model.
[0008] Alternatively, a surface of the main rod is provided with a scale along
a length direction
of the main rod.
[0009] By adopting the above technical solution, when the feed assembly is
inserted into the
tunnel opening via the main rod, the position of the insertion can be judged
according to the
scale on the main rod. The anchor rod can be inserted into the anchor hole
position conveniently
and quickly according to the preset position data of the anchor hole in the
physical model during
3D modeling.
[0010] Alternatively, the auxiliary device for making a 3D printed model
further includes a
support mechanism; the support mechanism includes a base and a bracket; the
bracket is
configured to slide up and down relative to the base and be fixed at a
position; and the main rod
is supported on the bracket and slides along a length direction of the main
rod relative to the
bracket.
[0011] By adopting the above technical solution, the main rod is supported on
the bracket, so the
shaking of the main rod is reduced during moving, which is beneficial to the
alignment of the
anchor rod with the anchor hole of the physical model. In the process of
inserting the anchor rod
into the anchor hole, the possibility of new fissures caused by the shaking of
the main rod when
inserting the anchor rod is reduced.
[0012] Alternatively, the bracket includes an arc-shaped part matching with an
outline of the
tunnel opening of the physical model; the arc-shaped part is provided with a
mounting seat
configured to slide along an arc surface of the arc-shaped part and be fixed
at a position; the
main rod is snap connected with the mounting seat; the arc-shaped part is
provided with an angle
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scale; the mounting seat is provided with a pointer; and a direction of the
pointer is parallel to an
axis of the perforation in the fixed member.
[0013] By adopting the above technical solution, since the axial angle of each
anchor hole is
known during 3D modeling, the axis direction of the anchor rod can be judged
by the pointer
when the main rod slides along the arc-shaped part with the mounting seat, so
that the anchor rod
may be aligned with the anchor hole conveniently and quickly.
[0014] Alternatively, the arc-shaped part has a rectangular cross-section, and
is defined with a
sliding groove on an outer arc surface; a elongated slot in communication with
the sliding groove
along the circumferential direction is formed in an end surface of the arc-
shaped part; the
mounting seat is configured to slide relative to the sliding groove; the
mounting seat is fixed with
a threaded post extending out of the elongated slot; and the threaded post is
in thread connection
with a nut.
[0015] By adopting the above technical solution, the mounting seat can slide
along the sliding
groove after the nut is loosened; the threaded post moves in the corresponding
elongated slot;
and the nut is tightened when the mounting seat position meets the
requirements. The operation
is simple and convenient.
[0016] Alternatively, a guide groove is formed in a surface of the main rod
along the length
direction of the main rod, and the mounting seat is fixedly provided with a
guide block
cooperating with the guide groove.
[0017] By adopting the above technical solution, the main rod will not rotate
and shake due to
the matching between the guide groove and the guide block when the main rod
moves, and the
stability of the anchor rod insertion operation is improved.
[0018] Alternatively, the base has one open end and an inner cavity; an end of
the bracket
extends into the cavity of the base and slides relatively; and an elastic
member is arranged in the
cavity of the base.
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[0019] By adopting the above technical solution, when the support is pressed
down, the elastic
member is compressed, then the height of the whole auxiliary tool is lowered,
which is beneficial
to the separation of the fixed member from the anchor rod and facilitates the
operation.
[0020] Alternatively, the feed assembly is installed at one end of the main
rod; the power
assembly includes a micro motor or a hand wheel and a transmission structure
installed at the
other end of the main rod; and the transmission structure is any one or two of
a belt transmission
structure, a chain transmission structure, and a gear transmission structure.
[0021] By adopting the above technical solution, both the micro motor and the
hand wheel may
conveniently drive the rotating member to rotate, and have simple structure
and convenient
installation and maintenance.
[0022] In the second aspect, the present application provides a method for
making a 3D printed
rock mass physical model by adopting the following technical solutions:
A method for making a 3D printed rock mass physical model, including the
following steps:
3D printing a sand mold model matrix integrally, in which the model matrix is
provided with a
tunnel opening and a plurality of anchor holes in an inner wall of the tunnel
opening; and
inserting the anchor rod into the anchor hole of the model matrix using the
above auxiliary
device for making a 3D printed tunnel model.
[0023] By adopting the above technical solution, the sand has structure and
components that are
closer to the rock mass, so the integrally printed model matrix reduces the
possibility that the gap
between the modules of the assembled model affects the experimental results.
The auxiliary
device inserts and fixes the anchor rod into the anchor hole, which can
simulate the actual
engineering state more realistically, and the test simulation data reflects
the actual engineering
situation more closely.
[0024] To sum up, the present application achieves at least one of the
following beneficial
technical effects:
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The anchor rod is firstly passed through the perforation of the fixed member
outside the physical
model, so that the slot in the anchor rod is aligned with the limiting ridge
in the fixed member,
and an end of the anchor rod extends into the rotating member; the end of the
anchor rod to be
flush with the end of the perforation of fixed member or to protrude a small
section by rotating
the rotating member. Then, the feed assembly and the anchor rod are inserted
into the tunnel
opening of the physical model via the main rod. When the anchor rod is moved
to align with the
anchor hole in the physical model, the rotating member is driven to rotate by
the power assembly.
Due to the screwed connection between the anchor rod and the rotating member,
and the
circumferential rotation of the anchor rod is restricted by the limiting
ridge, so that the anchor
rod is directionally moved along the perforation axis and inserted into the
anchor hole of the
physical model. It can simulate the actual engineering state more
realistically, and the test
simulation data reflects the actual engineering situation more closely.
BRIEF DESCRIPTION OF DRAWINGS
[0025] FIG. 1 is a structural schematic diagram illustrating the overall
structure of the auxiliary
device for making a 3D printed tunnel model in use according to the present
application;
Fig. 2 is a cross-sectional view of the A-A plane in Fig. 1;
Fig. 3 is a schematic diagram illustrating the overall structure according to
an embodiment of the
present application;
FIG. 4 is a cross-sectional view of the B-B plane illustrating the connection
structure of the
bracket and the base in FIG. 3;
Fig. 5 is a cross-sectional view of part C-C in Fig. 4;
Fig. 6 is a structural schematic diagram illustrating the connection structure
of the main rod and
the bracket;
Fig. 7 is a structural schematic diagram illustrating the anchor insertion
mechanism;
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FIG. 8 is a structural schematic diagram illustrating the connection
relationship between the feed
assembly and the anchor rod.
[0026] Description of reference numbers: 1. support mechanism; 11. base; 111.
elastic member;
12. bracket; 121. pressing plate; 122. sliding groove; 123. elongated slot;
13. cross rod; 2. main
rod; 21. guide groove; 3. anchor insertion mechanism; 31. micro motor; 32.
driving wheel; 33.
conveyor belt; 34. driven wheel; 35. rotating member; 36. fixed member; 361.
limiting ridge;
362. connecting plate; 4. mounting seat; 41. guide block; 42. pointer; 5.
anchor rod; 51. slot; 6.
model matrix; 61. tunnel opening; 62. anchor hole.
DETAILED DESCRIPTION
[0027] The present application will be further described in detail below in
combination with
FIGs. 1-8.
[0028] The embodiment of the present application discloses an auxiliary device
for making a 3D
printed tunnel model. Referring to FIG. 1 and FIG. 2, the auxiliary device for
3D printed tunnel
model includes a support mechanism 1 and a mounting seat 4 mounted to the
support mechanism
1. The mounting seat 4 is slidably connected to a main rod 2, on which an
anchor insertion
mechanism 3 is installed. The physical model of the 3D printed rock mass
includes a model
matrix 6 and an anchor rod 5 inserted into the model matrix 6. A tunnel
opening 61 is formed
through the model matrix 6, and a plurality of anchor hole 62 for insertion
are provided in the
model matrix 6 inside the tunnel opening 61. In use, the anchor rod 5 is pre-
installed on the
anchor insertion mechanism 3; the support mechanism 1 is placed on a platform,
and then the
anchor insertion mechanism 3 is extended into the tunnel opening 61 of the
model matrix 6 via
the main rod 2; the anchor rod 5 is aligned with the anchor hole 62 in the
model matrix 6 by
adjusting the inserted depth of the main rod 2, then the anchor insertion
mechanism 3 is activated
to insert the anchor rod 5 into the corresponding anchor hole 62 for fixing;
then the auxiliary
device is withdrawn from the model matrix 6; and the mechanical test of the 3D
printed rock
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mass physical model is carried out. Since the anchor rod 5 is contained in the
physical model, the
simulated data results of the test reflect the actual engineering situation
more realistically.
[0029] Referring to FIG. 3 and FIG. 4, the support mechanism 1 includes a base
11 and a bracket
12. The bracket 12 includes an arc-shaped part and support parts fixed at both
ends of the arc-
shaped part. There are two brackets 12 arranged side by side. The two brackets
12 are fixedly
connected by a cross rod 13 which is fixed on the support parts; each support
part corresponds to
one base 11, and the bases 11 on the same side of the two brackets 12 are also
fixedly connected
by the cross rod 13. The cross rod 13 may be fixed to the base 11 and the
bracket 12 by screws.
[0030] The base 11 may be a cuboid with an open end and an inner cavity. A
pressing plate 121
is fixed at one end of the bracket 12. One end of the support part with the
pressing plate 121
extends into the cavity of the base 11 and can slide relative to the base 11.
An elastic member
111 is provided in the inner cavity of the base 11, and a spring may be
selected as the elastic
member 111. The contour at the opening of the base 11 is smaller than the
contour of the
pressing plate 121 to prevent the bracket 12 from being detached from the base
11. The elastic
member 111 exerts a supporting force on the pressing plate 121 when the
bracket 12 is not
subjected to other external forces, so that the pressing plate 121 is close to
the open end of the
base 11; the support part can drive the pressing plate 121 to compress the
spring to contract and
deform, and the support part is inserted into the base 11 to adjust the height
of the entire support
mechanism 1 when the bracket 12 is subjected to external force.
[0031] Referring to FIG. 4 and FIG. 5, the arc-shaped part of the bracket 12
has a rectangular
cross-section and is provided with a sliding groove 122 on an outer arc
surface along the
circumferential direction, and the sliding groove 122 is a T-shaped groove. A
elongated slot 123
in communication with the sliding groove 122 along the circumferential
direction is formed on
an end surface of the arc-shaped part. The bracket 12 is provided with an
angle scale on the arc-
shaped part, and the angle scale may also be replaced by a fixed position mark
as required.
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[0032] Referring to FIG. 5 and FIG. 6, the main rod 2 has a circular cross-
section, and the
surface of the main rod 2 is provided with a guide groove 21 along the
generatrix direction. The
main rod 2 is provided with a scale along the length direction.
[0033] The mounting seat 4 is slidably arranged on the sliding groove 122 of
the bracket 12; one
-- end of the mounting seat 4 is provided with a sliding part that is adapted
to and slides relatively
to the sliding groove 122, and the other end of the mounting seat 4 is
provided with a clamping
part that has a contour matching with the main rod 2. The clamping part has a
circular arc shape
and a certain elasticity, so that the main rod 2 is inserted from the opening
of the clamping part
and then clamped. The clamping part is integrally provided with a guide block
41 matching with
-- the guide groove 21, so that the main rod 2 can only slide along the axial
direction of the
clamping part after being clamped into the clamping part of the mounting base
4.
[0034] In order to conveniently fix the position of the mounting seat 4, the
sliding part is
provided with a threaded post passing through the elongated slot 123; the
threaded post may be
fixed to the sliding part by insertion or by screwing. The threaded post is in
thread connection
-- with a nut. The mounting seat 4 and the bracket 12 are fixed in position by
rotating and
tightening the nut after the mounting seat 4 is moved to an appropriate
position.
[0035] The mounting seat 4 is fixed with a pointer 42 between the sliding part
and the clamping
part, and the pointer 42 is parallel to the plane where the angle scale is
located, so that the
position of the mounting seat 4 may be adjusted accurately.
-- [0036] Referring to FIG. 7 and FIG. 8, the anchor insertion mechanism 3
includes a feed
assembly and a power assembly, and the power assembly includes a micro motor
31 installed on
one end of the main rod 2 and a transmission structure arranged on the main
rod 2, in which the
transmission structure is belt transmission; the transmission structure
includes a driving wheel 32,
a driven wheel 34 and a conveyor belt 33 connected to the driving wheel 32 and
the driven wheel
34; the driving wheel 32 is coaxially fixed with the output shaft of the micro
motor 31, and the
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driven wheel 34 is rotatably connected to the main rod 2 at one end away from
the micro motor
31. In an alternative embodiment of the present application, the transmission
structure may also
be a chain transmission, a worm gear transmission, etc. The micro motor 31 may
be a forward
and reverse rotation motor. The micro motor 31 may also be replaced by a hand
wheel as
required.
10037] The feed assembly includes a fixed member 36 fixed on one end of the
main rod 2 close
to the driven wheel 34 and a rotating member 35 connected to the fixed member
36 by a
connecting plate 362. The connecting plate 362 is fixed to the fixed member 36
by welding or
screws. The connecting plate 362 is rotatably connected to the rotating member
35, and the
rotation mode may be a bearing connection. The fixed member 36 may be a
rectangular plate or
a plate of other shapes. The rotating member 35 is connected to the driven
wheel 34. A belt
transmission may be selected, and a gear transmission or a chain transmission
may also be
selected as required. In order to prevent the belt from falling off, the
surface of the rotating
member 35 is provided with a groove along the circumferential direction for
holding the belt.
The fixed member 36 is provided with a perforation, and a limiting ridge 361
in the inner wall of
the perforation. The perforation in the fixed member 36 is arranged coaxially
with the rotating
member 35.
[0038] The rotating member 35 may be a threaded sleeve, and the anchor rod 5
is in thread
connection with the rotating member 35. A surface of an anchor rod 5 is
defined with a slot 51 in
an axial direction. The slot 51 has a cross-section adapted to the limiting
ridge 361.
[0039] One end of the anchor rod 5 passes through the perforation in the fixed
member 36 and
then is in thread connection with the rotating member 35. Because the limiting
ridge 361
cooperates with the slot 51 in the anchor rod 5 to prevent the anchor rod 5
from rotating, the
anchor rod 5 moves along the perforation axis of the fixed member 36 when the
rotating member
35 rotates.
Date Regue/Date Received 2022-09-02
[0040] In an alternative embodiment of the present application, the surface of
the anchor rod 5 is
provided with a helical groove; the rotating member 35 is provided with a
through-hole having a
same outer diameter with the anchor rod 5; and the rotating member 35 is
provided with a
protrusion that may extend into the helical groove in the inner wall of the
perforation; the depth
of the helical groove is greater than the depth of the groove 51 to prevent
the protrusion from
slipping off from the groove 51 when the protrusion rotates to the
intersection of the helical
groove and the groove 51. The protrusion rotates as the rotating member 35
rotates. Since the
protrusion is located in the helical groove, the protrusion drives the anchor
rod 5 having the
helical groove to move along the axis of the through-hole.
[0041] In order to intuitively understand the axis direction of the anchor rod
5, the end of the
pointer 42 may be directed parallel to the axis of the rotating member 35.
[0042] The auxiliary device may be sized according to the cross-section of the
tunnel opening 61
in the model matrix 6, so that the auxiliary device may extend into the tunnel
opening 61.
[0043] A method for making a physical model by the auxiliary device for making
a 3D printed
tunnel model is as follows:
(1) Preparing the model matrix 6 for 3D printing:
51: the natural rock mass having fissure structure was 3D modelled and
outputted;
S2: the model matrix 6 is integrally printed by a 3D sand printing device.
[0044] (2) Installing the fixed anchor rod 5:
51: the anchor rod 5 is installed on the rotating member 35, and then the
auxiliary device is
extended into the tunnel opening 61, such that the bracket 12 is flush with
the end of the tunnel
opening 61;
S2: adjusting the position of the anchor rod 5: the main rod 2 is moved to a
predetermined
insertion depth according to the position of the anchor hole 62 designed for
the 3D model, and
the insertion depth of the main rod 2 may be judged by the scale on the main
rod 2; then the
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mounting seat 4 is moved and adjusted according to the axis angle of the
anchor hole 62, so that
the position corresponding to the pointer 42 and the angle scale on the
bracket 12 meets the
requirements, and then the mounting seat 4 is fixed; at this time, the axis of
the anchor rod 5 is
aligned with the anchor hole 62;
S3: the micro motor 31 is started, and the anchor rod 5 is inserted into the
anchor hole 62, and
stops moving when the anchor rod 5 is separated from the rotating member 35;
S4: the bracket 12 is pressed down to lower the height of the auxiliary
device; and the fixed
member 36 moves down and separates from the anchor rod 5 at the same time; ;
the auxiliary
device is pulled out from the tunnel opening 61; then other rods is used to
press the exposed part
of the anchor rod 5 into the anchor hole 62.
[0045] The remaining anchor rods 5 are installed by repeating the above steps,
then a 3D printed
rock mass physical model is produced, and the model is used for geotechnical
engineering test
simulation. Since there are anchor rods 5 in the physical model for support
and reinforcement,
the simulation data reflects the actual engineering more closely.
[0046] In order to improve the connection firmness of the anchor rod 5 and the
model matrix 6,
the surface of the anchor rod 5 may be coated with glue, and the physical
model is tested after
the glue hardens. The auxiliary device is used after being cleaned before the
glue is harden.
[0047] The above are all preferred embodiments of the present application, and
are not intended
to limit the protection scope of the present application. Therefore, all
equivalent modification
made according to the structure, shape and principle of the present
application falls into the
protection scope of the present application.
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