CN114839060A - Portable rock true triaxial test device and method - Google Patents
Portable rock true triaxial test device and method Download PDFInfo
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- CN114839060A CN114839060A CN202210432690.2A CN202210432690A CN114839060A CN 114839060 A CN114839060 A CN 114839060A CN 202210432690 A CN202210432690 A CN 202210432690A CN 114839060 A CN114839060 A CN 114839060A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0019—Compressive
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/025—Geometry of the test
- G01N2203/0256—Triaxial, i.e. the forces being applied along three normal axes of the specimen
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- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a portable rock true triaxial test device, which comprises a bottom plate, a sleeve, a top plate and four side pressure plates, wherein the cross section of the sleeve is rectangular, the four side pressure plates correspond to the four inner side walls of the sleeve one by one, each inner side wall of the sleeve is provided with a horizontal convex strip with a triangular longitudinal section, each horizontal convex strip is provided with an upper inclined plane and a lower inclined plane, the side pressure plates are provided with horizontal grooves corresponding to the horizontal convex strips, and the horizontal convex strips can be matched with the corresponding horizontal grooves; the bottom end of the sleeve is connected to the bottom plate, the top plate is connected with the top end of the sleeve, a driving device for driving the lifting shaft to lift is arranged on the top plate, the rock sample is placed in a cuboid space defined by the four side pressure plates, and the lifting shaft is located right above the rock sample; four top pressing plates can be detachably connected to the lifting shaft, and the bottom ends of the top pressing plates can be in close contact with the top ends of the corresponding side pressing plates. The invention improves the usability and portability of the portable rock true triaxial test device.
Description
Technical Field
The invention relates to the technical field of rock test detection, in particular to a portable rock true triaxial test device and a method.
Background
Due to the tectonic stress, rock in nature is in a true triaxial stress environment, and meanwhile, true triaxial testing of rock can reproduce the change of rock structure when standard-sized samples are used. However, at present, the research on the structural change of the rock is mostly carried out under the stress state of the conventional three shafts, so that the research on the structural change of the rock under the stress state of the true three shafts has important reference value for various engineering projects.
However, the portable rock true triaxial test device at home and abroad is arranged indoors at present, and the test device has the problems of high labor intensity for replacement, long test period, complex test operation and low test efficiency. Meanwhile, after coring on site, the rock sample is transported to a laboratory, and the rock sample can cause damage of different degrees, so that accurate mechanical parameters cannot be measured.
Disclosure of Invention
The invention aims to provide a portable rock true triaxial test device and a method, which are used for solving the problems in the prior art and improving the usability and portability of the portable rock true triaxial test device.
In order to achieve the purpose, the invention provides the following scheme:
the invention provides a portable rock true triaxial test device, which comprises a bottom plate, a sleeve, a top plate and four side pressure plates, wherein the cross section of the sleeve is rectangular, the four side pressure plates correspond to four inner side walls of the sleeve one by one, each inner side wall of the sleeve is provided with a horizontal convex strip with a triangular longitudinal section, each horizontal convex strip is provided with an upper inclined plane and a lower inclined plane, the side pressure plate corresponding to the inner side wall of the sleeve is provided with a horizontal groove corresponding to the horizontal convex strip, and the horizontal convex strip can be matched with the corresponding horizontal groove; the bottom end of the sleeve is detachably connected to the bottom plate, the top plate is detachably connected with the top end of the sleeve, a driving device for driving a lifting shaft to lift is arranged on the top plate, a rock sample is placed in a cuboid space defined by the four side plates, and the lifting shaft is located right above the rock sample; the lifting shaft can be detachably connected with four top pressure plates which correspond to the four side pressure plates one by one, and the bottom ends of the top pressure plates can be in close contact with the top ends of the corresponding side pressure plates; the top of the top pressure plate is fixedly connected with a horizontal constraint plate, a vertical screw rod is fixedly arranged on the top plate, the constraint plate is sleeved on the screw rod in a sliding mode, and a limit nut positioned above the constraint plate is connected to the screw rod in a threaded mode; and each side pressure plate is provided with a lateral pressure sensor, and the bottom plate is provided with an axial pressure sensor which is positioned right below the rock sample.
Preferably, all be provided with a plurality of from top to bottom arranging in proper order on every inside wall of telescopic horizontal sand grip.
Preferably, the bottom plate can be fixedly connected with the workbench or the ground through a fixing bolt.
Preferably, the sleeve, the side pressure plate, the top pressure plate and the lifting shaft are all made of steel.
Preferably, the driving device is a jack, a piston shaft of the jack is used as the lifting shaft, the top plate is provided with a through hole corresponding to the lifting shaft, and the lifting shaft penetrates through the through hole.
Preferably, the lifting shaft is connected with a horizontal connecting plate, and the four jacking plates are respectively connected with the connecting plate through pins.
A rock true triaxial test method under the condition of constant rigidity is based on the portable rock true triaxial test device and comprises the following steps:
(1) the portable rock true triaxial test device is transported to the site and assembled, and the bottom plate is fixed on a flat site by fixing bolts;
(2) the top pressure plate and the lifting shaft are fixedly connected through pins, the side pressure plates are matched with the inner side walls of the corresponding sleeves, a gap is ensured between the bottom ends of the side pressure plates and the bottom plate, and a rock sample is placed in a cuboid space defined by the four side pressure plates;
(3) starting a lateral pressure sensor and an axial pressure sensor, starting a driving device to drive a lifting shaft and a top pressure plate to move downwards, pressing the corresponding side pressure plate downwards by the top pressure plate, and converting the axial pressure into lateral pressure by the side pressure plate under the action of a horizontal convex strip and a horizontal groove so as to press the rock sample laterally;
(4) when the lateral pressure detected by the lateral pressure sensor reaches a set value, screwing down a limit nut to enable the bottom end of the limit nut to be in close contact with the top surface of the corresponding restraining plate on the top pressure plate, so that the restraining plate is limited in the vertical direction, and meanwhile, the top pressure plate is released from being connected with the lifting shaft;
(5) continuing to drive the lifting shaft downwards, and performing the step (4);
(6) repeating the step (5) until the lateral pressures detected by all the lateral pressure sensors reach a set value;
(7) and continuously driving the lifting shaft downwards, applying axial pressure on the rock sample through the lifting shaft until the rock sample is damaged, recording the displacement, the axial pressure and the confining pressure value of the jack at the moment, and calculating the triaxial compression strength of the rock under the condition of constant rigidity.
Compared with the prior art, the invention has the following technical effects:
the portable rock true triaxial test device and the method are simple to operate, convenient and fast to assemble, capable of being used on site and capable of obtaining various parameters of rock structure changes better and more accurately. According to the portable rock true triaxial test device and the method, the top pressure plate is arranged to press the side pressure plate downwards, and the side pressure plate generates lateral pressure through the inclined plane between the horizontal raised line and the horizontal groove, so that a jack applying acting force in the horizontal direction is omitted, the weight of the whole device is greatly reduced, and the portability of the whole device is facilitated.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a front view of the portable rock true triaxial test apparatus of the present invention;
FIG. 2 is a top view of the portable rock true triaxial test apparatus of the present invention;
FIG. 3 is a schematic view of a part of the structure of the portable rock true triaxial test device of the present invention;
FIG. 4 is a schematic structural diagram of a side pressure plate in the portable rock true triaxial test device according to the present invention;
wherein: 1. a base plate; 2. a sleeve; 3. a top plate; 4. a jack; 5. side pressing plates; 6. a rock sample; 7. a lifting shaft; 8. a top pressing plate; 9. a connecting frame; 10. a restraint plate; 11. a screw; 12. a connecting plate; 13. a limit nut; 14. an axial pressure sensor; 15. a lateral pressure sensor.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.
The invention aims to provide a portable rock true triaxial test device and a method, which are used for solving the problems in the prior art and improving the usability and portability of the portable rock true triaxial test device.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
As shown in fig. 1 to 4: the embodiment provides a portable rock true triaxial test device, which comprises a bottom plate 1, a sleeve 2, a top plate 3 and four side pressure plates 5, wherein the cross section of the sleeve 2 is rectangular, the four side pressure plates 5 are in one-to-one correspondence with four inner side walls of the sleeve 2, each inner side wall of the sleeve 2 is provided with a plurality of horizontal convex strips which are sequentially arranged from top to bottom, the longitudinal section of each horizontal convex strip is triangular, one side of each triangular convex strip, which is close to the sleeve 2, is vertical, the horizontal convex strip is provided with an upper inclined plane and a lower inclined plane, the side pressure plates 5 corresponding to the inner side walls of the sleeve 2 are provided with horizontal grooves corresponding to the horizontal convex strips one to one, and the horizontal convex strips can be matched with the corresponding horizontal grooves; when the side pressure plates 5 are subjected to vertical downward pressure, the side pressure plates can move obliquely downward under the action of the inclined surfaces of the horizontal convex strips and the horizontal grooves, so that the vertical downward pressure is converted into lateral pressure.
The bottom of sleeve 2 can be connected on bottom plate 1 with dismantling through the bolt, roof 3 can be connected with dismantling through the bolt with sleeve 2's top, is provided with on the roof 3 to be used for driving lift axle 7 to carry out the jack 4 that goes up and down, and jack 4 links firmly with roof 3 through link 9, and the piston axle of jack 4 is as lift axle 7, and roof 3 corresponds lift axle 7 and is provided with the through-hole, and lift axle 7 passes the through-hole. The rock sample 6 is placed in a cuboid space surrounded by the four side pressure plates 5, and the lifting shaft 7 is positioned right above the rock sample 6.
The lifting shaft 7 can be detachably connected with four top pressing plates 8 which correspond to the four side pressing plates 5 one by one; specifically, a horizontal connecting plate 12 is fixedly connected to the lifting shaft 7, and the four top pressure plates 8 are respectively connected with the connecting plate 12 through pins; the bottom end of the top pressure plate 8 can be in close contact with the top end of the corresponding side pressure plate 5; the top of the top pressure plate 8 is fixedly connected with a horizontal restraint plate 10, the top plate 3 is fixedly provided with a vertical screw rod 11, the restraint plate 10 is sleeved on the screw rod 11 in a sliding manner, the screw rod 11 is in threaded connection with a limit nut 13 positioned above the restraint plate 10, a notch for the restraint plate 10 to move up and down is formed in the connecting frame 9, and the restraint plate 10 penetrates through the notch; an axial pressure sensor 15 is arranged on each side pressure plate 5, and an axial pressure sensor 14 which is positioned right below the rock sample 6 is arranged on the bottom plate 1.
The bottom plate 1 can be fixedly connected with a workbench or the ground through a fixing bolt so as to ensure the overall stability of the device. The sleeve 2, the side pressing plates 5, the top pressing plate 8 and the lifting shaft 7 are all made of steel.
A rock true triaxial test method under the condition of constant rigidity is based on the portable rock true triaxial test device and comprises the following steps:
(1) the portable rock true triaxial test device is transported to the site and assembled, and the bottom plate 1 is fixed on a flat site by fixing bolts;
(2) the top pressing plate 8 and the lifting shaft 7 are fixedly connected through pins, the side pressing plates 5 are matched with the inner side walls of the corresponding sleeves 2, a gap is ensured between the bottom ends of the side pressing plates 5 and the bottom plate 1, and rock samples 6 are placed in a cuboid space defined by the four side pressing plates 5;
(3) starting an axial pressure sensor 15 and an axial pressure sensor 14, starting a driving device to drive a lifting shaft 7 and a top pressing plate 8 to move downwards, enabling the top pressing plate 8 to press the corresponding side pressing plates 5 downwards, and converting the axial pressure into lateral pressure by the side pressing plates 5 under the action of horizontal convex strips and horizontal grooves so as to press the rock sample 6 laterally;
(4) when the lateral pressure detected by the axial pressure sensor 15 reaches a set value, the limiting nut 13 is screwed down, so that the bottom end of the limiting nut 13 is in close contact with the top surface of the corresponding restraining plate 10 on the top pressure plate 8, the restraining plate 11 is limited in the vertical direction, and the top pressure plate 8 and the lifting shaft 7 are simultaneously disconnected;
(5) continuing to drive the lifting shaft 7 downwards, and performing the step (4) until the lateral pressure detected by all the axial pressure sensors 15 reaches a set value;
(6) and (3) continuously driving the lifting shaft 7 downwards, applying axial pressure to the rock sample 6 through the lifting shaft 7 until the rock sample 6 is damaged, wherein in the process, because the connection between all the top pressure plates 8 and the horizontal connecting plate 12 on the lifting shaft 7 is released in the step (5), the positions of all the top pressure plates 8 and all the side pressure plates 5 are fixed, and the stress on the rock sample 6 continuously changes along with the downward pressure of the lifting shaft 7, a true triaxial test of the rock under the condition of constant rigidity is simulated, the displacement, the shaft pressure and the confining pressure value of the jack 4 at the moment are recorded, and the triaxial compression strength of the rock under the condition of constant rigidity is calculated.
It should be noted that a plurality of groups of side pressure plates 5 made of materials with different rigidities can be prepared, the rigidity of the same group of four side pressure plates 5 is the same, and the rigidity of different groups of side pressure plates 5 is different, so as to simulate the rock true triaxial test under different constant rigidities; when the side pressing plates 5 are pressed down, the side pressing plates 5 can be grouped to adjust the stress in different directions, for example, the left and right top pressing plates 8 are detached first, the front and back top pressing plates 8 are installed, the front and back side pressing plates 5 are pressed down, the front and back top pressing plates 8 are detached again, the left and right top pressing plates 8 are installed, and the left and right side pressing plates 5 are pressed down.
In the description of the present invention, it should be noted that the terms "top", "bottom", "inside", "front", "back", "left", "right", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.
The principle and the implementation mode of the present invention are explained by applying specific examples in the present specification, and the above descriptions of the examples are only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (7)
1. The utility model provides a true triaxial test device of portable rock which characterized in that: the cross section of the sleeve is rectangular, the four side pressing plates correspond to the four inner side walls of the sleeve one by one, each inner side wall of the sleeve is provided with a horizontal convex strip with a triangular longitudinal section, each horizontal convex strip is provided with an upper inclined plane and a lower inclined plane, the side pressing plate corresponding to the inner side wall of the sleeve is provided with a horizontal groove corresponding to the horizontal convex strip, and the horizontal convex strip can be matched with the corresponding horizontal groove; the bottom end of the sleeve is detachably connected to the bottom plate, the top plate is detachably connected with the top end of the sleeve, a driving device for driving a lifting shaft to lift is arranged on the top plate, a rock sample is placed in a cuboid space defined by the four side plates, and the lifting shaft is located right above the rock sample; the lifting shaft can be detachably connected with four top pressure plates which correspond to the four side pressure plates one by one, and the bottom ends of the top pressure plates can be in close contact with the top ends of the corresponding side pressure plates; the top of the top pressure plate is fixedly connected with a horizontal constraint plate, a vertical screw rod is fixedly arranged on the top plate, the constraint plate is sleeved on the screw rod in a sliding mode, and a limit nut positioned above the constraint plate is connected to the screw rod in a threaded mode; and each side pressure plate is provided with a lateral pressure sensor, and the bottom plate is provided with an axial pressure sensor which is positioned right below the rock sample.
2. The portable rock true triaxial test apparatus of claim 1, wherein: all be provided with a plurality of from top to bottom arranging in proper order on telescopic every inside wall horizontal sand grip.
3. The portable rock true triaxial test apparatus of claim 1, wherein: the bottom plate can be fixedly connected with the workbench or the ground through a fixing bolt.
4. The portable rock true triaxial test apparatus of claim 1, wherein: the sleeve, the side pressing plate, the top pressing plate and the lifting shaft are all made of steel.
5. The portable rock true triaxial test apparatus of claim 1, wherein: the driving device is a jack, a piston shaft of the jack is used as the lifting shaft, the top plate is provided with a through hole corresponding to the lifting shaft, and the lifting shaft penetrates through the through hole.
6. The portable rock true triaxial test apparatus of claim 5, wherein: the lifting shaft is connected with a horizontal connecting plate, and the four jacking plates are respectively connected with the connecting plate through pins.
7. A rock true triaxial test method under the condition of constant rigidity is characterized in that the portable rock true triaxial test device based on any one of claims 1 to 6 comprises the following steps:
(1) the portable rock true triaxial test device is transported to the site and assembled, and the bottom plate is fixed on a flat site by fixing bolts;
(2) the top pressure plate and the lifting shaft are fixedly connected through pins, the side pressure plates are matched with the inner side walls of the corresponding sleeves, a gap is ensured between the bottom ends of the side pressure plates and the bottom plate, and a rock sample is placed in a cuboid space defined by the four side pressure plates;
(3) starting a lateral pressure sensor and an axial pressure sensor, starting a driving device to drive a lifting shaft and a top pressure plate to move downwards, pressing the corresponding side pressure plate downwards by the top pressure plate, and converting the axial pressure into lateral pressure by the side pressure plate under the action of a horizontal convex strip and a horizontal groove so as to press the rock sample laterally;
(4) when the lateral pressure detected by the lateral pressure sensor reaches a set value, screwing down a limit nut to enable the bottom end of the limit nut to be in close contact with the top surface of the corresponding restraining plate on the top pressure plate, so that the restraining plate is limited in the vertical direction, and meanwhile, the top pressure plate is released from being connected with the lifting shaft;
(5) continuing to drive the lifting shaft downwards, and performing the step (4);
(6) repeating the step (5) until the lateral pressures detected by all the lateral pressure sensors reach a set value;
(7) and continuously driving the lifting shaft downwards, applying axial pressure on the rock sample through the lifting shaft until the rock sample is damaged, recording the displacement, the axial pressure and the confining pressure value of the jack at the moment, and calculating the triaxial compression strength of the rock under the condition of constant rigidity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210432690.2A CN114839060A (en) | 2022-04-24 | 2022-04-24 | Portable rock true triaxial test device and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210432690.2A CN114839060A (en) | 2022-04-24 | 2022-04-24 | Portable rock true triaxial test device and method |
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| Publication Number | Publication Date |
|---|---|
| CN114839060A true CN114839060A (en) | 2022-08-02 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210432690.2A Withdrawn CN114839060A (en) | 2022-04-24 | 2022-04-24 | Portable rock true triaxial test device and method |
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| CN (1) | CN114839060A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110907268A (en) * | 2019-12-31 | 2020-03-24 | 贵州理工学院 | Rock shear strength tester |
-
2022
- 2022-04-24 CN CN202210432690.2A patent/CN114839060A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110907268A (en) * | 2019-12-31 | 2020-03-24 | 贵州理工学院 | Rock shear strength tester |
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Application publication date: 20220802 |
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