CN114414401A - Large-scale shearing instrument for regneration test of residual strength of slip-band soil and application - Google Patents
Large-scale shearing instrument for regneration test of residual strength of slip-band soil and application Download PDFInfo
- Publication number
- CN114414401A CN114414401A CN202111547833.6A CN202111547833A CN114414401A CN 114414401 A CN114414401 A CN 114414401A CN 202111547833 A CN202111547833 A CN 202111547833A CN 114414401 A CN114414401 A CN 114414401A
- Authority
- CN
- China
- Prior art keywords
- shearing
- shear
- test
- arm
- force
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000010008 shearing Methods 0.000 title claims abstract description 143
- 238000012360 testing method Methods 0.000 title claims abstract description 83
- 239000002689 soil Substances 0.000 title claims abstract description 47
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 72
- 238000006073 displacement reaction Methods 0.000 claims abstract description 36
- 238000012544 monitoring process Methods 0.000 claims abstract description 32
- 230000008929 regeneration Effects 0.000 claims abstract description 31
- 238000011069 regeneration method Methods 0.000 claims abstract description 31
- 230000007246 mechanism Effects 0.000 claims abstract description 13
- 238000000034 method Methods 0.000 claims description 20
- 230000008569 process Effects 0.000 claims description 20
- 230000005059 dormancy Effects 0.000 claims description 8
- 230000009471 action Effects 0.000 claims description 6
- 230000001276 controlling effect Effects 0.000 claims description 6
- 230000001105 regulatory effect Effects 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 3
- 230000001174 ascending effect Effects 0.000 claims description 2
- 238000007599 discharging Methods 0.000 claims description 2
- 238000004088 simulation Methods 0.000 claims 1
- 238000013461 design Methods 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract description 3
- 238000002474 experimental method Methods 0.000 description 4
- 230000002829 reductive effect Effects 0.000 description 4
- 230000000284 resting effect Effects 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000005389 magnetism Effects 0.000 description 3
- 230000007958 sleep Effects 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- 230000033228 biological regulation Effects 0.000 description 2
- 239000004927 clay Substances 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007596 consolidation process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000007306 functionalization reaction Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 229940029329 intrinsic factor Drugs 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 230000036544 posture Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 230000008667 sleep stage Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 230000009974 thixotropic effect Effects 0.000 description 1
- 230000001550 time effect Effects 0.000 description 1
Images
Classifications
-
- 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
- G01N3/24—Investigating strength properties of solid materials by application of mechanical stress by applying steady shearing forces
-
- 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
- G01N3/02—Details
Abstract
The invention provides a large-scale shearing instrument for a regeneration test of the residual strength of slipperiness soil and application thereof, wherein the large-scale shearing instrument comprises a shearing test system, a load system, a monitoring control system, a water inlet and drainage system and a container; the load system is used for loading the shear test system; the load system comprises a lifting mechanism, a lifting arm, a telescopic force arm which horizontally slides with the lifting arm, a force application shaft and a pressure plate connected with the lower end of the force application shaft, wherein the lifting mechanism is used for lifting or descending the lifting arm in the vertical direction; the monitoring control system comprises a displacement monitor, a pressure sensor and a computer, wherein the displacement monitor is used for monitoring the horizontal displacement of the telescopic force arm and the vertical displacement of the lifting arm, and the pressure sensor is arranged on the load acting surface of the load system to the shear test system. The invention adopts a large-scale shearing design, and overcomes the defect that the conventional direct shear apparatus cannot shear the slip-band soil to be residual at one time because of too small unidirectional shearing displacement.
Description
Technical Field
The invention belongs to the technical field of landslide engineering tests, and particularly relates to a shear mechanics testing instrument under a linear stress path condition and application thereof.
Background
After the landslide slides along the sliding surface for a long distance, the sliding soil of the landslide is cut to a residual stage, and the corresponding shear strength is reduced to the residual. Therefore, the residual strength of the landslide soil is generally considered to be an important parameter for evaluating landslide stability and anti-skid design.
Since the implementation of the three gorges project, the restarting phenomenon of the old landslide is frequently encountered due to the periodic water storage and drainage of the reservoir. After the landslide which slips in the geological history period stops slipping, the landslide stops slipping for a long time, and at the later stage, due to the excitation of external factors (such as reservoir water level lifting), the landslide is prompted to slip along the original sliding surface again, which is called as the restart of the old landslide. It is generally recognized that the strength of the sliding surface remains a residual strength when the old landslide is restarted. However, many scholars find that the corresponding shear strength is often greater than the residual strength when the old landslide is restarted, and the phenomenon of regeneration of the residual strength is shown by parameter inversion. Some scholars explain the strength regeneration mechanism, and think that the slipperiness takes place thixotropic hardening, consolidation creep, structure strengthening and other series of processes during the dormancy period, is the intrinsic factor causing the strength regeneration, and has obvious time effect, and the longer the dormancy time, the higher the regeneration strength when the landslide restarts.
The regeneration of the residual strength has important significance for landslide stability and anti-skid design, and the determination of the value needs to adopt a test means. At present, people mainly adopt conventional direct shear and ring shear tests to carry out the residual strength regeneration test. The general method is that forward pressure is applied to a shearing surface, then a soil body is sheared to be residual at a certain shearing rate, then the shearing force is released to stop shearing, a sample is kept static for a period of time under the condition that the forward pressure is not changed so as to simulate a landslide dormancy period, the shearing is restarted after the dormancy period expires, and the shearing strength of the landslide surface during restarting is measured. But the disadvantages are: (1) the conventional direct shear apparatus has a small shearing distance, and needs to adopt a mode of reciprocating push shear to carry out experiments, wherein the mode has a condition of unidirectional sliding of an illegal landslide; (2) when the test is carried out by using a ring shear apparatus, the shearing is stopped by releasing the shearing force, but actually, the shearing force on the sliding surface still exists when the landslide is dormant. It is difficult for a ring shear to simulate this real condition.
Disclosure of Invention
In order to overcome the defects of the conventional direct shear apparatus and the conventional ring shear apparatus in the regeneration strength test of the topsoil, the invention aims to provide a novel shear apparatus suitable for the regeneration test of the topsoil residual strength by combining the basic characteristics of the landslide evolution development. The equipment is matched with a computer servo control system, can make a regulation and control instruction on the power component according to real-time transmitted monitoring data, and improves the automation and multi-functionalization level of the instrument. The equipment simultaneously meets the innovative requirements and the actual requirements of strong grindability, great engineering significance and the like.
Therefore, the above purpose of the invention is realized by the following technical scheme:
the utility model provides a large-scale shearing appearance for smooth area soil residual strength regeneration test which characterized in that: the large-scale shearing instrument for the regeneration test of the residual strength of the slippery soil comprises a shearing test system, a load system, a monitoring control system, a water inlet and drainage system and a container;
the shear test system is arranged in the container, and the load system is used for loading the shear test system;
the water inlet and outlet system is used for adding water or discharging water into the container;
the load system comprises a lifting mechanism, a lifting arm, a telescopic force arm which horizontally and smoothly slides with the lifting arm, a force applying shaft and a pressure plate connected with the lower end of the force applying shaft, wherein the lifting mechanism is used for lifting or descending the lifting arm in the vertical direction. And a force applying shaft and a pressure plate connected with the lower end of the force applying shaft are arranged below the free end of the telescopic force arm, and the telescopic force arm drives the force applying shaft and the pressure plate arranged at the lower end of the force applying shaft to load the shear test system under the lifting action of the lifting mechanism.
Meanwhile, the telescopic arm of force is a driven member, one side of the telescopic arm of force penetrates into the lifting arm, and the telescopic arm of force and the lifting arm of force are in friction-free contact through smooth balls. On one hand, when the lifting arm descends, the telescopic arm of force can be driven to move downwards together. On the other hand, when the upper disc mould is displaced due to shearing dislocation, the telescopic force arm can be pulled to generate smooth horizontal movement along the inner part of the lifting arm.
The monitoring control system comprises a displacement monitor, a pressure sensor and a computer, wherein the computer is used for controlling the lifting mechanism to ascend or descend the lifting arm in the vertical direction, the displacement monitor and the pressure sensor are connected with the computer through signals, the displacement monitor is used for monitoring the horizontal displacement of the telescopic force arm and the vertical displacement of the lifting arm, and the pressure sensor is arranged on the load acting surface of the load system to the shear test system.
While adopting the technical scheme, the invention can also adopt or combine the following technical scheme:
as a preferred technical scheme of the invention: the shear test system comprises an upper disc mold, a lower disc mold, and an upper shear box and a lower shear box which are arranged between the upper disc mold and the lower disc mold, wherein the upper shear box and the lower shear box are respectively clamped into the upper disc mold and the lower disc mold, and a certain inclination angle is formed between the contact surface of the upper shear box and the contact surface of the lower shear box and the horizontal direction; and the upper shearing box and the lower shearing box are filled with slippery soil. The inclined shearing surface is arranged, so that the normal stress and the shearing stress on the inclined shearing surface are all decomposed by the vertical resultant force on the upper part of the inclined shearing surface. On the one hand, the linear stress path is controlled, and on the other hand, the shear stress of the shear surface in the dormant stage is ensured to be maintained.
The upper disc mould and the lower disc mould are mainly used for loading the shearing box and controlling the shearing angle. Push grooves are respectively arranged in the bottom surface of the upper disc mould and the top surface of the lower disc mould, and the push grooves and the upper disc mould are symmetrical and form a certain inclination angle. The inner side wall of the push groove is provided with a telescopic bolt hole.
The device can be matched with an upper disc mould and a lower disc mould with push grooves with different inclination angles, and can be used for carrying out shear tests at different shear angles.
A gap with a certain width is reserved between the upper shearing box and the lower shearing box to control the formation of a shearing surface in the test, and correspondingly, the shearing surface divides the slip band soil sample into an upper slip band soil disk and a lower slip band soil disk. The upper and lower shearing boxes correspond to the pushing grooves in the upper and lower disc molds respectively, the sizes of the upper and lower shearing boxes are matched, and the shearing boxes can be loaded into the pushing grooves. The outer surface of the shearing box is provided with a telescopic bolt, the telescopic bolt is retracted into the shearing box before the shearing box is arranged in the pushing groove, and after the shearing box is arranged in the pushing groove, the computer sends an instruction to stretch out the bolt and stretch into the bolt hole in the inner wall of the pushing groove, so that the shearing box is fixedly connected with the pushing groove, and the angle of the shearing surface is controlled by the inclination angle of the pushing groove.
As a preferred technical scheme of the invention: the bottom of the lower disc die is provided with a support, and the lower end of the support is abutted against the inner bottom of the container and is fixed.
As a preferred technical scheme of the invention: the top of the shear test system is fixed with a bearing plate, the top of the bearing plate is provided with a groove for accommodating the pressurizing plate, so that the pressurizing plate can move downwards and be embedded into the groove of the bearing plate to pressurize the bearing plate, and the upper disc mold can pull the pressurizing plate to generate horizontal displacement components together with a pressurizing shaft and a telescopic force arm on the upper part of the pressurizing plate in the shearing dislocation process.
As a preferred technical scheme of the invention: an electromagnet is arranged in the pressure bearing plate and used for sucking the pressure bearing plate in a power-on state. When a sample is loaded before a test, the magnetism of the upper disc mould is started by electrifying, the upper disc mould is attracted with a pressurizing plate on the upper part of the upper disc mould, the upper disc mould is driven by a lifting arm to rise and fall to a preset position, and a preset space is formed between the upper disc mould and the lower disc mould, so that a shearing box containing a slip soil sample can be loaded into the upper disc mould and the lower disc mould. After the sample loading is finished, the power is cut off to release the magnetism of the bearing plate, and then the shearing test stage that the lower disc is fixed and the upper disc moves can be started.
As a preferred technical scheme of the invention: the lifting mechanism comprises a stand column, an oil pressure pump, a vertical guide rail and a frequency converter, wherein the oil pressure pump is arranged at the top of the stand column, the vertical guide rail is arranged along a column body of the stand column, and the frequency converter is used for regulating and controlling the oil pressure pump to lift or descend along the vertical guide rail by driving a lifting arm.
The lifting arm support is a driving component and has a hollow structure, the telescopic arm of force is a driven component, one side of the telescopic arm support penetrates through the lifting arm, and the lifting arm support are in friction-free contact. On one hand, the frequency converter can drive the lifting arm to lift along the vertical guide rail through regulating and controlling the oil pressure pump, and drives the telescopic force arm and the pressurizing shaft connected with the telescopic force arm to lift, so that loading and unloading of the pressurizing plate to the bearing plate are realized. On the other hand, when the shearing box is dislocated to cause the horizontal displacement component of the upper disc mould in the test, the telescopic force arm can be driven to smoothly move along the inner part of the lifting arm, and no mechanical frictional resistance is ensured.
As a preferred technical scheme of the invention: the displacement monitor is arranged on a lifter at the monitoring column, and the lifter is used for ascending or descending the displacement monitor along the monitoring column. Meanwhile, the data is fed back to the computer through a signal transmission cable, so that the displacement control of the computer to the test is realized.
As a preferred technical scheme of the invention: the water inlet and drainage system comprises a water level monitoring scale, a water inlet faucet and a drain pipe arranged at the bottom of the container, wherein the water level monitoring scale is used for monitoring the corresponding water storage position when the shearing surface is restarted to slide in real time, the drain pipe is used for adjusting the height of the water level in the container, and the water inlet faucet is used for injecting water into the groove-shaped container until the water storage position in the container does not pass through part or all of the sliding surface and is enough for restarting the sliding of the shearing surface due to the reduction of effective normal stress. After the water level when the shear surface is restarted and slid is read by the water level monitoring scale, the experiment is finished, and the drain pipe can be opened to drain the water in the container.
As a preferred technical scheme of the invention: the invention is matched with a computer servo control system, can monitor the monitoring data fed back by the displacement monitor in real time according to the preset shearing rate, thereby realizing the rate control of the shearing process by coordinating the stress state of the shearing surface in time, and simultaneously, can also start the force control mode in the dormancy and restart stages by combining the use of the pressure sensor.
The second objective of the present invention is to provide the application of the large shear apparatus for the test of regeneration of remnant strength of zonal soil in the shear test of zonal soil, which comprises various shear stages, such as an initial stage, a peak stage, a remnant stage, a resting stage, and a restarting stage, and a shear surface stress analysis required for the various stages.
It is still another object of the present invention to provide the use of the large-scale shearer for the test of reclaiming the residual strength of the topsoil as described above for obtaining the reclaiming strength of the topsoil, and quantify the friction angle and cohesion of the reclaiming strength according to the test measurement results.
Compared with the prior art, the invention has the following beneficial effects:
1) the invention adopts a large-scale shearing design, and avoids the defect that the conventional direct shear apparatus cannot shear the slip band soil to be residual at one time because of too small unidirectional shearing displacement.
2) The invention adopts the inclined shearing surface arrangement, so that the shearing surface is automatically under the action of shearing stress in the test process, thereby ensuring the existence of the shearing stress in the dormant antiskid stage. And the conventional ring shear apparatus usually cancels shearing force in the dormant stage of the test due to the arrangement of the horizontal annular shearing surface. Therefore, the invention is more suitable for the practical situation that the shearing force exists when the landslide is dormant.
3) The invention adopts the inclined shearing surface arrangement, so that the normal stress and the shearing stress on the shearing surface are all decomposed by the vertical resultant force acting on the upper part of the shearing surface through stress, thereby ensuring a linear stress path and having clear mechanical conditions.
4) The invention is arranged by the inclined shearing surface, so that the shearing stress of the shearing surface in the dormant stage is kept, and the sliding of the shearing surface is restarted by adopting a water level lifting mode. The restarting process of the reservoir landslide is restored in principle.
5) The invention is matched with a computer servo control system, and can supervise the monitoring data fed back by the displacement monitor in real time according to the preset shearing rate, thereby realizing rate control. Meanwhile, the force control mode can be started when necessary by combining the use of the pressure sensor.
6) The invention attaches importance to the influence of the mechanical friction resistance of the instrument, and adopts two measures to eliminate the influence, namely, the width of a gap between an upper shearing box and a lower shearing box is controlled, and the mechanical friction between the shearing boxes during shearing is avoided; second, by way of example: the smooth ball controls the smooth movement between the telescopic force arm and the lifting arm, and ensures that the shearing surface is only acted by vertical resultant force.
Drawings
FIG. 1 is a schematic representation of a large shear apparatus for the test of regeneration of the residual strength of the slipband soil provided by the present invention;
FIG. 2 is a view in the direction A-A in FIG. 1;
FIG. 3 is a view in the direction B-B in FIG. 1;
FIG. 4 is a view in the direction C-C of FIG. 1;
FIG. 5 is a perspective view of a shear test system;
FIG. 6 is a schematic representation of a shear box and prefabricated mold with different shear tilt angles;
FIG. 7 is a schematic representation of a shear test phase;
FIG. 8 is a load-displacement graph;
FIG. 9 is a schematic view of the shear plane after water addition and pressure reduction;
FIG. 10 is a graphical representation of the linear stress path experienced by the shear plane throughout the test;
FIG. 11 is a schematic view of various shear dip conditions;
FIG. 12 is a graphical representation of determination of the residual strength and the regeneration strength of the topland soil;
wherein, 1-right side wall of the container, 1 a-water level monitoring scale, 1 b-left side wall of the container, 2-water inlet tap, 3-water level, 4-upper disc mould, 5-upper disc tyre soil, 6-upper shearing box, 7-telescopic bolt, 8-drain pipe, 9-support, 10-shearing inclination angle, 11-lower disc mould, 12-base, 13-lower shearing box, 14-shearing surface, 15-lower disc tyre soil, 16-upright post, 17-pressingForce sensor, 18-monitoring column, 19-displacement monitor, 20-lifter, 21-frequency converter, 21 a-vertical guide rail, 22-computer, 23-oil pressure pump, 24-lifting arm, 24 a-smooth ball, 25-telescopic arm, 26-shearing surface subjected to vertical resultant force, 27-stress shaft, 28-pressure bearing plate, 29-pressure bearing plate, 30-shearing surface length, 31-shearing surface width, 32-lower disc mould push groove, 32 a-upper disc mould push groove, 33-telescopic bolt hole, 34-gravity W intercept, 35-horizontal dislocation distance, 36-peak position horizontal dislocation distance, 37-residual position one horizontal dislocation distance, 38-residual stage two horizontal dislocation distance, 39-dormant position horizontal dislocation distance, 40-vertical force at peak position, 41-vertical force at residual position one, 42-vertical force at residual position two, 43-vertical force at resting position, 44-curve of vertical force with horizontal dislocation distance, 45-water level line, 46-water level H147-height of water pressure at the end C of the effective shear plane, 48-level H249-height of water pressure at point B in front of the effective shear plane.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and examples, and the present invention is not limited to the following examples.
The invention provides a large-scale shearing instrument for a regeneration test of the residual strength of slipperiness soil, which has a structure shown in figure 1 and mainly comprises five functional parts, namely a shearing part, a hydraulic loading system, a monitoring control system, a water inlet and drainage system and a container. The container is the cell type, settles on base 12, and in the container was all arranged in except that computer 22 to the functional part of other experimental usefulness, computer 22 located the container, can be operated by the experimenter, realized the automatic control to the experiment. The computer 22 is the core of the monitoring control system, is connected with a signal transmission cable, can receive real-time data fed back by a pressure sensor, a displacement monitor and the like, and sends real-time instructions to components such as a frequency converter, a pressure bearing plate (with an electromagnet) and the like according to preset target parameters, automatically regulates and controls the test steps and servo-controls the test process.
The bottom, the lower plate mould 11 is fixed on the bottom of the container through the support 9, and is kept still in the test; a drain 8 opens at the bottom of the vessel and extends through the base 12 to allow water to drain at the end of the test. In the middle, it can be seen that the top surface of the lower disc mold 11 and the bottom surface of the upper disc mold 4 are symmetrical, and are provided with a certain inclination angle α (marked as 10), a certain distance is controlled between the two, and push grooves are respectively formed, so that a shear box containing a slip band soil sample is just filled in the shear box, and the telescopic bolt 7 fixedly connects the shear box with the molds. Corresponding to the upper and lower disc molds, the shear box is divided into an upper shear box 6 and a lower shear box 13 which are symmetrical, a seam width is left between the upper shear box and the lower shear box, the formation of a shear surface 14 can be guided in a test, the shear angle is controlled to be alpha (marked as 10), and the shear surface 14 divides the slip band soil sample into upper disc slip band soil 5 and lower disc slip band soil 15. The upper part, the top surface of the upper disc mould 4 is provided with a square groove, a groove-shaped bearing plate 28 of an electric control electromagnet is fixedly connected in the square groove, a pressure sensor 17 is arranged in the bearing plate 28, and when a pressure plate 29 is pressed down and embedded into the groove-shaped bearing plate 28 in the test process, the pressure F applied to the bearing plate 28 by the pressure plate 29 can be measured by the pressure sensor 17. The pressure plate 29 drives the telescopic arm 25 and the force application shaft 27 to move downwards through the lifting arm 24, so that the pressure plate 29 applies pressure to the pressure bearing plate 28. Or before sample loading, an electromagnet arranged in the bearing plate 28 is started, and is attracted by the pressurizing plate 29, so that the upper disc mold 4 is prepositioned under the driving of the lifting arm 24. Meanwhile, the telescopic arm 25 is a driven member, the left side of the telescopic arm penetrates into the hollow lifting arm 24, and a smooth ball 24a is arranged between the hollow lifting arm and the hollow lifting arm for contact, so that the telescopic arm 25 can move up and down along with the lifting arm 24 and can move smoothly along the inner part of the lifting arm 24 along with the horizontal dislocation of the sample. On the left side, a vertical column 16 is arranged at the bottom of the container, an oil pressure pump 23 is erected at the top of the column, a vertical guide rail 21a is arranged on the column body, and a lifting arm 24 is erected on the vertical guide rail 21a and can freely lift along the vertical guide rail 21a under the regulation and control of a frequency converter 21. The monitoring column 18 is arranged at the left side in the container, a lifter 20 is arranged on the monitoring column, and the displacement monitor 19 can move up and down along the lifter 20 to monitor the horizontal displacement of the telescopic arm 25 and the vertical displacement of the lifting arm 24 in real time. The periphery is enclosed by the container wall to form a groove-shaped enclosed space for storing water. Wherein the faucet 2 of intaking locates container right side wall 1, and the mark has water level monitoring scale 1a on the right side wall 1. Opposite the right side wall 1 is the left container side wall 1 b. In addition, during the shear test, the shear plane is subjected to a vertical resultant force G (the total weight of the upper disc mold, the pressure bearing plate, the pressure sensor, the upper shear box and the upper disc of the crawler soil is denoted by 26, W and the pressure F applied to the pressure bearing plate by the pressure bearing plate during the test together form the vertical resultant force G ═ W + F acting on the shear plane, the angle of the shear plane is α, so that the positive pressure on the shear plane is G · cos α, and the shear force is G · sin α.
Fig. 2 is a view in the direction a-a in fig. 1, showing the relationship between the components on the top surface of the upper plate mold 4. It can be seen that the upper plate mold 4, the pressurizing plate 29 and the bearing plate 28 are all in the shape of long strips on the plane, and the upper part of the pressurizing plate 29 is connected with the pressurizing shaft 27 and is abutted against the groove-shaped bearing plate 28 on the lower part thereof.
Fig. 3 is a view in the direction B-B in fig. 1, showing that the lower cutting box 13 containing the clay sample is loaded in the pushing groove 32 of the lower disc mold 11, and the long cutting surface 14 is marked with a (marked with 30) and B (marked with 31).
Fig. 4 is a view in the direction C-C of fig. 1, showing the spatial relationship between the telescopic arm 25 and the lifting arm. It can be seen that the telescopic arm 25 passes through the hollow lifting arm 24, and a smooth ball 24a is arranged between the telescopic arm 25 and the hollow lifting arm 24 for contact, and the telescopic arm 25 can move smoothly along the inside of the lifting arm 24.
Fig. 5 is a perspective view of the shear test system, showing the positional relationship between the shear box and the mold push groove after sample loading is completed. It can be seen that the shear box can be loaded into the lower and upper shear boxes 13 and 6 along the push grooves, so that the lower and upper shear boxes are inserted into the lower and upper mold push grooves 32 and 32a, respectively. Above the upper plate mold 4, a pressing plate 29 to which the pressing shaft 27 is fixedly attached is seen to abut against a pressure bearing plate 28, which can be loaded and unloaded.
FIG. 6 is an illustration of a shear box and prefabricated mold with different shear rake angles. As can be seen in fig. 6(a), the shear box is divided into symmetrical upper shear box 6 and lower shear box 13, which are filled with the clay sample and have a certain gap width to guide the formation of shear plane 14. The side surface of the shearing box is provided with a telescopic bolt 7 which is retracted into the shearing box before being arranged in the mold push groove, and after the shearing box is arranged in the mold push groove, the telescopic bolt can be controlled by a computer instruction to extend out and be inserted into a bolt hole 33 on the side surface of the push groove, so that the shearing box is embedded with the mold. Fig. 6(b) to 6(d) show the prefabricated molds with different shearing inclination angles, and it can be seen that the shearing boxes can be loaded into the corresponding mold pushing grooves with different postures, and the inserting pin holes 33 are arranged in the pushing grooves. During the test, the test can be carried out based on different prefabricated molds, so that the residual strength regeneration research under different shear angle conditions can be realized.
The following experimental procedure was carried out in conjunction with fig. 7 to 12:
first, dress appearance
First, a sample of the raw slippery soil is taken and trimmed to a size suitable for the shear box so that the upper and lower shear boxes can be nested thereon, thereby forming a shear box sample as shown in fig. 6 (a).
And then, selecting a corresponding mold for sample loading according to the shearing angle. The electromagnet of the pressure bearing plate 28 of the upper disc mold 4 is first electrically controlled to attract the pressure plate 29, and the lift arm 24 is then actuated to vertically lift the upper disc mold 4 to a predetermined height. Then, the lower disc mold 11 is fixed on the support 9, so that the upper disc mold and the lower disc mold are aligned, and the space between the upper disc mold and the lower disc mold is just allowed to be filled with the cutting box. Then, the shear box sample is pushed into the groove along the mold push groove, and the telescopic plug pin 7 on the shear box is regulated and controlled to be inserted into the plug pin hole 33 in the groove, so that the shear box is embedded with the mold. After the sample is loaded, the power is cut off to release the magnetism of the pressure bearing plate 28, the suction force is removed, the loading and unloading of the pressure bearing plate 28 by the pressure plate 29 can be normally carried out, and the shearing test stage that the lower disc is fixed and the upper disc moves is carried out.
Second, loading and shearing
After the sample loading is completed, a shear test is performed. The test was carried out by applying a vertical load G26 to the test specimen with its shear component G · sin α along the shear plane.
As shown in fig. 7, the shear is performed from the initial position to the residual position two, a shear rate control mode is adopted in the test, that is, the horizontal displacement component of the telescopic moment arm 25 (the component is the horizontal displacement component caused by the shear dislocation) is monitored in real time in the loading process, and is fed back to the computer 22 to calculate the corresponding shear rate, and the computer 22 controls the load applied to the shear surface 14 in reverse according to the preset shear rate value, so as to ensure that the shear rate caused by the load action is controlled to be the preset rate in real time, and realize the servo control of the shear rate. Because the shearing keeps constant speed, the shearing surface is according to Newton's second lawThe shearing force and the shearing resistance on the steel plate 12 are kept equal at all times to obtain a formula (1), wherein c is cohesive force, phi is a friction angle, a is the length of a shearing surface, b is the width of the shearing surface, l is a horizontal offset distance, and alpha is a shearing inclination angle. The experimental mechanical curve characteristics were analyzed from fig. 8: g26 consists of the upper disc mold 4, the pressure bearing plate 28, the pressure sensor 17, the upper shear box 6, the total weight W (labeled 34) of the upper disc casing 5 and the force F exerted by the pressure plate 29, so the shear curve 44 in fig. 8 starts with W34; during the process of shearing from the initial position to the peak position, the horizontal offset l35 is increased to lp36, the friction parameters c and phi are gradually increased to peak values cp、φpTherefore, it is inferred from the formula (1) and the experience that G26 needs to be increased by Gp40; in the process of clipping the peak position to the residual position I (i.e. the initial position of the residual stage), lp36 to lr137, c, phi from cp、φpGradually decrease to a residual value cr、φrThus, G is represented by the formula (1)p40 need to be reduced to G in a non-linear mannerr141; during the process of continuing to shear the first residual position to the second residual position,. lr137 is increased to lr238, residual value cr、φrUnchanged, therefore, G is known from the formula (1)r141 linearly decreases to Gr242, judging whether the shearing reaches a residual stage in the test mainly according to the characteristics.
After the residue, it is cut to the rest position, l, from the rest position two deceleration as shown in FIG. 7r238 is increased to l s39, the process maintains the residual strength (c)r、φr) And the shear rate gradually decreased to 0. According to Newton's third law, this process can be expressed by the formula (2), and G is knownr2The 42 is required to be continuously reduced to G s43, at which time the shearing is just stopped. Then maintain G s43, the sleep is performed for a long time without changing. As shown in figure 7, in order to avoid the upper disc zonate soil from overturning around the lower disc zonate soil bottom point C in the shearing process, the middle point P (action point of resultant force G26) of the upper disc zonate soil cannot shear the point C, so that control is needed
Thirdly, adding water to restart after dormancy
After stopping sliding, keep GsThe shear plane is simulated in a resting state for a long time (stop time is selected as required) without changing 43. After the sleep is finished, the glide is restarted in the water level 45 up mode.
Fig. 9 shows the situation where water is added to the vessel to cause the upper disc of the ballast 5 to restart along the shear plane. A, C are marked points from head to tail of the sliding band soil on the lower wall, and since the lower wall is fixed, the elevation of the point A is marked as HAElevation of point C is HC. After the sliding belt soil is dislocated, the front ends of the upper disc and the lower disc are connected with a contact, and the horizontal dislocation distance between the contact and the point A is l s39. The effective shear plane is a segment BC, and the dip angle of the shear plane is recorded as alpha.
The water pressure experienced at the shear plane was calculated in two cases.
The first situation is as follows: when water level height H 146, when the effective sliding surface BC section is not beyond the point B, the water level line intersects with the point O, the OC section is seen to be immersed by water, and the shear surface water pressure is calculated as follows:
the water pressure height at the point O is 0, and the water pressure height at the point C is delta h C47，ΔhC＝H1-HCThe length of the OC section is
Thus the water pressure U1＝0.5·b·γw·ΔhC 2And/sin α, b31 is the shear face width.
Case two: when water level height H 248 when the point B is exceeded, the BC section of the effective sliding surface is completely immersed by water, and the water pressure of the sliding surface is calculated as follows:
the horizontal offset distance between the point B and the point A is l s39, thus obtaining an elevation H at point BB＝HA-lsTan. alpha. was obtained. The water pressure height at the point B is delta hB＝H2-HBThe water pressure height at the point C is delta hC＝H2-HCAnd the length of BC segment is
a30 is the total shear plane length, so water pressure U2＝0.5·b·γw·(ΔhB+Δhc)·(a-ls/. alpha.), b31 is the shear face width.
In the water adding process, the change of the water level is monitored in real time, and the real-time change of the water pressure on the effective shearing surface BC can be obtained according to the situation I or the situation II. And subtracting the water pressure from the positive pressure G · cos α on the effective shearing surface BC, and dividing by the area of the effective shearing surface BC to obtain a real-time change value of the effective positive stress σ' of the shearing surface BC in the water adding process. Since the sleep stage G · cos α is constant, σ' decreases as the water level rises during the water addition. While the shear force G sin α remains unchanged at this stage.
This step requires continuous addition of water until the shear plane is restarted.
Four, shear plane effective stress path
The shear plane effective stress path may be transformed from the test loading curve 44 of fig. 8.
Since the inclination angle α of the shearing surface 14 is fixed, the ratio of the shearing stress τ to the effective positive stress σ' on the shearing surface during the shearing process (except during the raising of the water level 45) is always tan α. Accordingly, the stress path on the shear plane 14 during shearing can be obtained as shown in fig. 10. It can be seen that: starting position e point starts from the initial stress plane (circular plane, radius p is W/ab) and then rises to the peak f point at an angle α to the horizontal, which corresponds to the starting to peak G in fig. 8p40 sections; from point f, the angle alpha with the horizontal is again decreased to a residual point G, which corresponds to the peak value G in FIG. 8p40 to a residue Gr2Stage 42, friction parameter (c) due to residual stager、φr) Since the value is unchanged, point G includes G in FIG. 8 as shown by formula (1)r141 to Gr2A residual shear stage between 42; ③ g is at an angle alpha with the horizontal and falls to the resting point hh point long time sleep, which corresponds to peak G in FIG. 8r242 to GsAnd 43, segments.
After the dormancy is finished, the water level is continuously raised from the point h, so that the effective positive stress sigma' is reduced, the shearing stress tau is unchanged, the stress path develops along hj, and the shearing is restarted on the shearing surface at the point j.
Fifthly, acquiring regeneration strength parameters
By using prefabricated moulds and selecting different shear inclination angle conditions (fig. 11) respectively to carry out the test, the effective stress paths of the whole test process under different shear inclination angles can be obtained as shown in fig. 12. FIG. 12 shows the respective shear tilt angles αi、αi+1、αi+1For example, the respective effective stress paths are shown, and according to the Moore Coulomb criterion, the residual strength parameter (friction angle phi) of the slip zone soil can be obtained by fittingrC, cohesion forcer) And a regeneration strength parameter (friction angle phi)zC, cohesion forcez). Since the residual intensity is regenerated during the rest period, the regenerated intensity envelope is generally located above the residual intensity envelope and the tilt angle increases.
And (3) parameter control:
in order to ensure that the test is normally carried out, relevant parameters alpha (shearing inclination angle), W (total weight of the upper disc mold, the bearing plate, the pressure sensor, the upper shearing box and the upper disc of the sliding strip soil), a (shearing surface length) and b (shearing surface width) of the experimental instrument need to meet the following conditions:
firstly, in order to ensure that a shearing surface can dislocate, the arranged shearing inclination angle needs to satisfy the formula (3);
secondly, in order to ensure that the loading G is increased when the peak value position is cut from the initial position, the parameters need to satisfy the formula (4);
thirdly, in order to ensure that the shearing surface can be controlled to stop shearing after the residual stage, and simultaneously to avoid the overturning of the upper shearing box around the bottom point C of the lower shearing box in the shearing process, the middle point P (namely the resultant force action point, see figure 7) of the upper shearing box needs not to be capable of shearing the bottom point C of the lower shearing box, so that the parameters need to satisfy the formula (5).
α＞φp (3)
cp、φpIs the peak cohesion and the peak friction angle, cr、φrResidual cohesion and residual angle of friction,/pSec α is the shear displacement at the peak, all of which are the attributes of the topland soil itself, and can be obtained in advance by a conventional direct shear test. And then according to the formulas (3) to (5), corresponding instrument parameters can be designed to ensure the development of the regeneration test of the residual strength of the topsoil.
The above-described embodiments are intended to illustrate the present invention, but not to limit the present invention, and any modifications, equivalents, improvements, etc. made within the spirit of the present invention and the scope of the claims fall within the scope of the present invention.
Claims (10)
1. The utility model provides a large-scale shearing appearance for smooth area soil residual strength regeneration test which characterized in that: the large-scale shearing instrument for the regeneration test of the residual strength of the slippery soil comprises a shearing test system, a load system, a monitoring control system, a water inlet and drainage system and a container;
the shear test system is arranged in the container, and the load system is used for loading the shear test system;
the water inlet and outlet system is used for adding water or discharging water into the container;
the load system comprises a lifting mechanism, a lifting arm, a telescopic force arm which horizontally slides with the lifting arm, a force application shaft and a pressure plate connected with the lower end of the force application shaft, wherein the lifting mechanism is used for lifting or descending the lifting arm in the vertical direction;
a force application shaft and a pressure plate connected with the lower end of the force application shaft are arranged below the free end of the telescopic force arm, and the telescopic force arm drives the force application shaft and the pressure plate arranged at the lower end of the force application shaft to load a shear test system under the lifting action of the lifting mechanism;
the telescopic arm of force is a driven member, one side of the telescopic arm of force penetrates into the lifting arm, and the telescopic arm of force and the lifting arm of force are in friction-free contact through smooth balls; on one hand, when the lifting arm descends, the telescopic force arm can be driven to move downwards together, and on the other hand, when the upper disc mould is displaced due to shearing dislocation, the telescopic force arm can be pulled to smoothly and horizontally move along the inner part of the lifting arm;
the monitoring control system comprises a displacement monitor, a pressure sensor and a computer, wherein the computer is used for controlling the lifting mechanism to ascend or descend the lifting arm in the vertical direction, the displacement monitor and the pressure sensor are connected with the computer through signals, the displacement monitor is used for monitoring the horizontal displacement of the telescopic force arm and the vertical displacement of the lifting arm, and the pressure sensor is arranged on the load acting surface of the load system to the shear test system.
2. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: the shear test system comprises an upper disc mold, a lower disc mold, and an upper shear box and a lower shear box which are arranged between the upper disc mold and the lower disc mold, wherein the upper shear box and the lower shear box are respectively clamped into the upper disc mold and the lower disc mold, and a certain inclination angle is formed between the contact surface of the upper shear box and the contact surface of the lower shear box and the horizontal direction; the upper shearing box and the lower shearing box are filled with the slippery soil, and a gap with a certain width is reserved between the upper shearing box and the lower shearing box so as to control the shearing surface.
3. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 2, which is characterized in that: the bottom of the lower disc mold is provided with a support, and the lower end of the support abuts against the inner bottom of the container.
4. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: the top of the shear test system is fixed with a bearing plate, the top of the bearing plate is provided with a groove for accommodating a pressurizing plate, so that when shearing dislocation occurs, the upper disc mould can draw the pressurizing plate pressed into the groove of the bearing plate, and the pressurizing plate, the pressurizing shaft and the telescopic arm of force on the upper part of the pressurizing plate can generate horizontal displacement components.
5. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: an electromagnet is arranged in the pressure bearing plate, can suck the pressurizing plate in a power-on state, and is mainly used for pre-positioning the upper disc die before the test is started.
6. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: the lifting mechanism comprises a stand column, an oil pressure pump, a vertical guide rail and a frequency converter, wherein the oil pressure pump is arranged at the top of the stand column, the vertical guide rail is arranged along a column body of the stand column, and the frequency converter is used for regulating and controlling the oil pressure pump to lift or descend along the vertical guide rail by driving a lifting arm.
7. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: the displacement monitor is arranged on a lifter at the monitoring column, and the lifter is used for ascending or descending the displacement monitor along the monitoring column.
8. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: the water inlet and drainage system comprises a water level monitoring scale, a water inlet faucet and a drainage pipe, wherein the drainage pipe is arranged at the bottom of the container, the water inlet faucet is used for injecting water into the container, the water level monitoring scale is used for monitoring the height of the water level, and the drainage pipe is used for adjusting the height of the water level in the container; the mode of injecting water into the container to improve the water level is adopted, so that the shearing surface is promoted to restart and slide due to effective positive stress reduction, and the high simulation of the restart of the old landslide is realized.
9. The large shear apparatus for the regeneration test of the residual strength of the slippery soil according to claim 1, which is characterized in that: the monitoring control system can supervise the monitoring data fed back by the displacement monitor in real time according to the preset shearing rate, so that the rate control of the shearing process is realized by coordinating the stress state of the shearing surface in time, and meanwhile, the force control mode can be started in the dormancy and restart stages by combining the use of the pressure sensor.
10. The use of the large scale shearer for the test of the regeneration of the residual strength of the topsoil according to claim 1 in the shear test of the topsoil and the acquisition of the regeneration strength.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111547833.6A CN114414401B (en) | 2021-12-16 | 2021-12-16 | Large shearing instrument for slide belt soil residual strength regeneration test and application |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111547833.6A CN114414401B (en) | 2021-12-16 | 2021-12-16 | Large shearing instrument for slide belt soil residual strength regeneration test and application |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114414401A true CN114414401A (en) | 2022-04-29 |
| CN114414401B CN114414401B (en) | 2024-02-06 |
Family
ID=81267061
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111547833.6A Active CN114414401B (en) | 2021-12-16 | 2021-12-16 | Large shearing instrument for slide belt soil residual strength regeneration test and application |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114414401B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116256250A (en) * | 2023-05-16 | 2023-06-13 | 中国科学院西北生态环境资源研究院 | Dead weight type direct shear apparatus for testing shear strength of movable floor base plate and test method |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050103350A (en) * | 2004-04-26 | 2005-10-31 | 한국지질자원연구원 | Joint shear test system |
| US20130112013A1 (en) * | 2011-11-08 | 2013-05-09 | Korea Institute Of Geoscience And Mineral Resources (Kigam) | Ring shear apparatus considering wall-slip effect |
| CN104007025A (en) * | 2014-05-08 | 2014-08-27 | 河海大学 | Multifunctional tilt table device used for testing interfacial shear strength characteristics of geotechnical synthetic material |
| US20150338208A1 (en) * | 2013-11-12 | 2015-11-26 | Bae Systems Information And Electronic Systems Integration Inc. | Phase resolved shearography for remote sensing |
| CN107330224A (en) * | 2017-07-24 | 2017-11-07 | 中国地质大学（武汉） | A kind of Analysis of Slope Stability slices method of the non-hypothesis in slitting intermolecular forces inclination angle |
| CN107543789A (en) * | 2017-08-30 | 2018-01-05 | 中国地质大学（武汉） | A kind of side slope model test method and system for studying open air trestle exploitation explosion dynamic instability mechanism |
| CN111141622A (en) * | 2020-01-19 | 2020-05-12 | 中国科学院武汉岩土力学研究所 | Tiltable shearing device |
| US20200262039A1 (en) * | 2019-02-14 | 2020-08-20 | Wuyi University | Device for measuring equivalent shear stress between shield screw conveyor and modified muck |
| CN111814369A (en) * | 2020-06-18 | 2020-10-23 | 中国地质大学（武汉） | Strip division method capable of accurately calculating force inclination angle between strips and stability safety coefficient of side slope |
| CN113138134A (en) * | 2021-03-26 | 2021-07-20 | 中国地质大学（武汉） | Direct shear tester for testing strength of sliding belt and direct shear test method |
| CN113702208A (en) * | 2021-08-26 | 2021-11-26 | 深圳大学 | Shear control instrument under three-dimensional space condition and control method thereof |
-
2021
- 2021-12-16 CN CN202111547833.6A patent/CN114414401B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050103350A (en) * | 2004-04-26 | 2005-10-31 | 한국지질자원연구원 | Joint shear test system |
| US20130112013A1 (en) * | 2011-11-08 | 2013-05-09 | Korea Institute Of Geoscience And Mineral Resources (Kigam) | Ring shear apparatus considering wall-slip effect |
| US20150338208A1 (en) * | 2013-11-12 | 2015-11-26 | Bae Systems Information And Electronic Systems Integration Inc. | Phase resolved shearography for remote sensing |
| CN104007025A (en) * | 2014-05-08 | 2014-08-27 | 河海大学 | Multifunctional tilt table device used for testing interfacial shear strength characteristics of geotechnical synthetic material |
| CN107330224A (en) * | 2017-07-24 | 2017-11-07 | 中国地质大学（武汉） | A kind of Analysis of Slope Stability slices method of the non-hypothesis in slitting intermolecular forces inclination angle |
| CN107543789A (en) * | 2017-08-30 | 2018-01-05 | 中国地质大学（武汉） | A kind of side slope model test method and system for studying open air trestle exploitation explosion dynamic instability mechanism |
| US20200262039A1 (en) * | 2019-02-14 | 2020-08-20 | Wuyi University | Device for measuring equivalent shear stress between shield screw conveyor and modified muck |
| CN111141622A (en) * | 2020-01-19 | 2020-05-12 | 中国科学院武汉岩土力学研究所 | Tiltable shearing device |
| CN111814369A (en) * | 2020-06-18 | 2020-10-23 | 中国地质大学（武汉） | Strip division method capable of accurately calculating force inclination angle between strips and stability safety coefficient of side slope |
| CN113138134A (en) * | 2021-03-26 | 2021-07-20 | 中国地质大学（武汉） | Direct shear tester for testing strength of sliding belt and direct shear test method |
| CN113702208A (en) * | 2021-08-26 | 2021-11-26 | 深圳大学 | Shear control instrument under three-dimensional space condition and control method thereof |
Non-Patent Citations (6)
| Title |
|---|
| TING-KAI NIAN 等: "Strength behavior of slip-zone soils of landslide subject to the change of water content", 《NATURAL HAZARDS》, pages 711 - 721 * |
| 刘新荣 等: "土石混合体的剪切面分形特征及强度产生机制", 《岩石力学与工程学报》, pages 2260 - 2274 * |
| 廖建民 等: "采用环剪仪对滑带土抗剪强度特性的研究", 《武汉理工大学学报》, pages 2013 - 10 * |
| 狄圣杰 等: "潮间带原位剪切波速特性探讨及应用分析", 《岩石力学与工程学报》, pages 2053 - 2060 * |
| 胡伟 等: "大型原位直剪试验设备改进研制与应用", 《岩土力学》, pages 905 - 912 * |
| 谢强 等: "饱和粉质黏土残余强度剪切速率效应试验研究", 《三峡大学学报(自然科学版)》, pages 52 - 55 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116256250A (en) * | 2023-05-16 | 2023-06-13 | 中国科学院西北生态环境资源研究院 | Dead weight type direct shear apparatus for testing shear strength of movable floor base plate and test method |
| CN116256250B (en) * | 2023-05-16 | 2023-08-04 | 中国科学院西北生态环境资源研究院 | Dead weight type direct shear apparatus for testing shear strength of movable floor base plate and test method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114414401B (en) | 2024-02-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109540788B (en) | Method and system for testing bonding performance of rock soil and anchoring body under simulated ground pressure effect | |
| CN107314926B (en) | Compaction soil sample test device and sample preparation method thereof | |
| WO2018006585A1 (en) | Multi-functional true triaxial rock drilling test system and method | |
| CN114414401A (en) | Large-scale shearing instrument for regneration test of residual strength of slip-band soil and application | |
| US6491107B2 (en) | Method and apparatus for running spooled tubing into a well | |
| CN109406268A (en) | A kind of ess-strain control formula soil body test for tensile strength device and method | |
| CN116907999A (en) | Pipeline internal stress quality inspection device for plastic pipeline production | |
| US3470701A (en) | Means for making concrete piles | |
| CN214331700U (en) | Pipeline positioning support for water supply and drainage engineering | |
| CN110595744B (en) | Operation method of strain strengthening process equipment | |
| CN104251126B (en) | Wellhead of water injection well tests blowout hookup | |
| CN110567811B (en) | Concrete body confining pressure loading device for anchor cable drawing experiment | |
| CN214301526U (en) | Lifting table type tidal simulation device | |
| CN211374327U (en) | Concrete strength detection device capable of improving working efficiency | |
| CN112326945B (en) | Deep roadway surrounding rock tight fracture shear excitation anti-reflection grouting test device and method | |
| CN1254669C (en) | Double lever loading in situ soil direct shear apparatus | |
| CN204627509U (en) | Exempt to climb formula hydraulic installalion blowout preventer for test borehole | |
| CN108490159B (en) | Device and method for testing pumping performance of freshly-mixed cement-based material | |
| CN114940451B (en) | Hydraulic lifting machine | |
| CN2366844Y (en) | Machine for investigating external pressureof concrete pipe | |
| CN204479409U (en) | The device that a kind of double hard ground material continues quantitatively to exert pressure | |
| CN207379836U (en) | Adjustable horizontal hydraulic press | |
| CN219327902U (en) | Engineering machinery support leg convenient to height-adjusting | |
| CN111398133A (en) | Soil engineering penetration slope and fall tester | |
| RU2454530C1 (en) | Method for dewaxing of oil wells tubing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |