CN115235904A - Cohesive lubricating strip soil expansion force testing device and testing method - Google Patents

Abstract

The invention discloses a cohesive synovial fluid soil expansive force testing device and a testing method, and the cohesive synovial fluid soil expansive force testing device comprises an instrument testing pedestal, a volume adjusting and expanding device, an expansion testing cylinder, a sensing equipment assembly, a data acquisition system and a liquid injection device, wherein the instrument testing pedestal provides a testing environment condition, the expansion testing cylinder is arranged on a laboratory bench of the instrument testing pedestal, a sample preparation target can be realized by matching an upper honeycomb base plate with a lifting rod, and after water flow is injected into the liquid injection device from a liquid inlet at the bottom of the expansion testing cylinder, the axial expansive force, the annular expansive force and the temperature which are monitored by the sensing equipment assembly are recorded and stored in real time by the data acquisition system. The invention can realize the expansive force test of the cohesive zonal soil under different physical attribute state conditions and environmental state conditions, including the axial expansive force and the annular expansive force, test data is recorded and stored by the data acquisition system, the test precision is higher, the test conditions are simpler and more, and more test attribute objects are provided.

Description

Cohesive lubricating strip soil expansion force testing device and testing method

Technical Field

The invention belongs to the technical field of geotechnical engineering tests, relates to quantitative testing of cohesive zonal soil expansion force, and particularly relates to a cohesive zonal soil expansion force testing device and a testing method formed by sliding a slope controlled by a coal-based stratum, an alumina texture layer and a weak stratum mainly based on expansive minerals along the weak layer.

Background

Landslide geological disasters are main disaster types influencing the survival and development of human beings in the world, and how to control and reduce landslide becomes a scientific and technical problem to be solved urgently. The clay-like slip-band soil is different from general slip-band soil, has water absorption and expansion characteristics due to the fact that the clay-like slip-band soil contains a large amount of clay minerals and is called as viscous slip-band soil.

In the prior art, a patent with a patent number of CN215677902U provides an expansive rock hydration expansive force testing device, which includes a mechanical test structure, a pressure recorder, and a computer system for data analysis, where the mechanical test structure includes a frame, a test force sensor and a pressure structure arranged in the frame, the pressure structure pressurizes a test piece arranged in the pressure structure through a pressurizing device at the lower part, the test piece is arranged in a bearing frame and arranged in an upper pressure water tank in the pressure structure through the bearing frame, the pressure structure further includes a lower pressure water tank communicated with the upper pressure water tank, and the expansive force testing of expansive rocks under different water pressures can be realized; the computer system of the rock mechanics test system and the test force sensor are adopted to collect test data in real time, the automation degree is high, the labor intensity of testers is greatly reduced, meanwhile, the influence of human factors on the test process is small, and the test precision is high. Patent No. CN 214583761U's patent provides an expansibility ground side direction bulging force and comprehensive testing device of expansion rate, including adorning in the box that detects the platform mesa admittedly, a box side direction is equipped with the opening, and the opening part is equipped with the adjustable fender that can remove in the box, and adjustable fender one side offsets with the expansibility ground in the box, and detachable bulging force measuring mechanism is installed to the opposite side, and the bulging force measuring mechanism survey is accomplished the back replacement and is become detachable deformation measurement mechanism. The detection device can effectively improve the accuracy of the measurement result by monitoring the expansive force and the expansive deformation of expansive rock soil and further deducing the rule between the deformation and the expansion force release. The device also has the advantages of simple detection method, convenient test process, low manufacturing cost, convenience, practicability and high safety, and can provide powerful data support for the analysis of actual engineering design.

To sum up, to the quantitative test research problem of cohesive slipband soil expansive force in landslide geological disasters, in the prior art, bentonite is mainly used as a research object to develop research on an expansive force testing device, and properties such as expansive force, expansion rate and the like of the bentonite under different environmental state conditions are researched in a simplified manner. At present, no expansion force testing device capable of adjusting different physical attribute state conditions and environmental state conditions simultaneously exists.

Disclosure of Invention

The invention aims to provide a cohesive slipband soil expansive force testing device and a testing method, which can realize the expansive force testing of cohesive slipband soil under different physical attribute state conditions and environmental state conditions, fill up the current related technical gap, and solve the problem that the prior art lacks an expansive force testing device capable of adjusting different physical attribute state conditions and environmental state conditions simultaneously.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a cohesive lubricating strip soil expansive force testing device, which comprises:

the device comprises a test pedestal, wherein an expansion test cylinder is arranged on the test pedestal, a liquid inlet is formed in the bottom of the expansion test cylinder, and a liquid outlet is formed in the top of the expansion test cylinder;

the volume adjusting and expanding device comprises a driving mechanism, an upper piston assembly and a lower piston assembly, the upper piston assembly comprises an upper honeycomb base plate and an upper piston rod, the upper honeycomb base plate is arranged at the upper part of a cylinder cavity of the expansion testing cylinder, and the upper piston rod is connected to the upper surface of the upper honeycomb base plate; the lower piston assembly comprises a lower honeycomb base plate and a lower piston rod, the lower honeycomb base plate is arranged at the lower part of a cylinder cavity of the expansion testing cylinder, the lower piston rod is connected to the lower surface of the lower honeycomb base plate, a sample space for containing a testing soil sample is formed among the upper honeycomb base plate, the lower honeycomb base plate and the cylinder wall of the expansion testing cylinder, at least one of the upper piston rod and the lower piston rod is connected with the driving mechanism, and the driving mechanism can enable the upper honeycomb base plate and the lower honeycomb base plate to be close to or far away from each other so as to adjust the volume of the sample space; permeable stone slabs are arranged between the test soil sample and the upper honeycomb base plate and between the test soil sample and the lower honeycomb base plate so as to intercept the test soil sample in the sample space in the test process;

the liquid injection device is connected with the liquid inlet through a pipeline and is used for injecting test liquid into the expansion test cylinder, and the temperature and the injection flow rate of the test liquid are adjustable;

the sensing equipment assembly comprises an axial expansion force detection device, a circumferential expansion force detection device and a temperature detection device, and the circumferential expansion force detection device and the temperature detection device are arranged on the expansion test cylinder; the axial expansion force detection device can detect the expansion force applied to the upper piston assembly and the lower piston assembly;

and the data acquisition system is in communication connection with the liquid injection device, the driving mechanism, the axial expansion force detection device, the annular expansion force detection device and the temperature detection device.

Optionally, the test bench comprises:

a bearing table;

the experiment table is arranged on the upper surface of the bearing table;

leveling cradling piece, leveling cradling piece set up in the upper surface of laboratory bench, just leveling cradling piece evenly is provided with many, all leveling cradling piece's bottom all with laboratory bench threaded connection, the inflation test drum set up in leveling cradling piece's top, and with all leveling cradling piece's top links to each other.

Optionally, the lower piston rod is arranged to penetrate through the bottom of the expansion testing cylinder, and the lower piston rod and the expansion testing cylinder are sealed by a universal plug seal, and the universal plug seal is fixed to the bottom of the expansion testing cylinder through a fixing cap; the bottom end of the lower piston rod is connected with the experiment table through the axial expansion force detection device, and the top end of the lower piston rod is connected with the lower honeycomb base plate;

the top end of the upper piston rod is connected with the driving mechanism through the axial expansion force detection device.

Optionally, the expansion testing device further comprises a top plate, the top plate is supported on the experiment table through a support rod, and the top plate is located above the expansion testing cylinder; the drive mechanism includes:

the hollow straight cylinder is arranged on the upper surface of the top plate;

the lifting rod is slidably sleeved in the hollow straight cylinder, the bottom end of the lifting rod penetrates through the top plate, and the top end of the lifting rod is used for being connected with a lifting power source;

the upper surface of the mounting disc is detachably connected with the bottom end of the lifting rod, the top end of the upper piston rod is connected with a tray, and the lower surface of the mounting disc is detachably connected with the tray; the axial expansion force detection device is arranged on the mounting disc and can detect the expansion force borne by the upper piston assembly;

the lifting rod fixing bolt penetrates through the side wall of the hollow straight cylinder and is in threaded connection with the side wall of the hollow straight cylinder, and the tail of the lifting rod fixing bolt can stretch into the hollow straight cylinder and is tightly propped against the lifting rod.

Optionally, four lifting rod fixing bolts are uniformly arranged along the circumferential direction of the hollow straight cylinder. Any lifting rod fixing bolt is perpendicular to the axial direction of the hollow straight cylinder.

Optionally, a slit view port extending along an axial direction of the expansion testing cylinder is formed in a side wall of the expansion testing cylinder, and the slit view port is communicated with a cylinder cavity of the expansion testing cylinder; a perspective glass plate is hermetically arranged in the slit sight opening and used for observing the change of the liquid level in the expansion testing cylinder; the outside of slit viewport still is provided with the liquid level scale.

Optionally, the sensing equipment assembly further comprises an image acquisition device, a dial indicator and a level gauge, the image acquisition device, the dial indicator and the level gauge are all in communication connection with the data acquisition system, wherein the image acquisition device is used for recording the liquid level rising height through the slit view port in real time, the dial indicator is arranged on the support rod, and the tops of the installation disc and the expansion testing cylinder are all provided with the level gauge.

Optionally, a side wall of the expansion testing cylinder opposite to the slit view port is provided with a plurality of mounting holes, and all the mounting holes are distributed along the axial direction of the expansion testing cylinder; any one of the mounting holes is communicated with the cylinder cavity of the expansion testing cylinder, the inner ends of part of the mounting holes are provided with the annular expansion force detection device, and the inner ends of the rest mounting holes are provided with the temperature detection device; the outer end of any one of the mounting holes is in threaded connection with a hollow screw so as to plug the mounting hole; the hollow screw is formed by butt joint of two half hollow screws, and a data wire of the annular expansion force detection device or the temperature detection device is embedded in an inner cavity of the hollow screw.

Optionally, the peripheries of the upper honeycomb base plate and the lower honeycomb base plate are both provided with grooves, a plurality of steel balls are embedded in the grooves, and the peripheries of the upper honeycomb base plate and the lower honeycomb base plate are in sliding fit with the inner cylinder wall of the expansion testing cylinder through the steel balls.

Meanwhile, the invention provides a method for testing the expansive force of the cohesive sliding band soil by adopting the device for testing the expansive force of the cohesive sliding band soil, which comprises the following steps:

step 1, paving the permeable stone slab on the upper honeycomb base plate, placing a test soil sample with target dry density quality into the expansion test cylinder, dismantling the installation disc, and driving the lifting rod to descend to compact the test soil sample to form a block-shaped test soil sample;

step 2, sequentially placing the permeable stone slabs and the upper honeycomb base plates connected with the upper piston rods and the trays above the blocky test soil samples, installing the installation disks, driving the lifting rods to descend until the installation disks are connected with the trays, and fixing the positions of the lifting rods;

step 3, resetting the axial expansion force detection device, the annular expansion force detection device and the temperature detection device;

step 4, injecting a test liquid into the expansion test cylinder, and starting a cohesive slipband soil expansion force test experiment;

step 5, collecting and storing the data of the sensing equipment assembly through the data acquisition system;

step 6, loosening the lifting rod to enable the axial expansion force generated by the massive test soil sample to drive the upper honeycomb base plate to move upwards, and simultaneously recording the axial expansion force, the annular expansion force and the temperature of the massive test soil sample after imbibition in real time through the sensing equipment assembly;

and 7, discharging the test liquid in the expansion test cylinder through the liquid inlet.

Optionally, in step 1, the pressing step of the block-shaped test soil sample includes:

step 11, placing a test soil sample with target dry density quality into the expansion test cylinder, driving the lifting rod to descend to compact the test soil sample, and forming a first layer of block-shaped test soil sample;

and step 12, placing the test soil sample with the same target dry density quality above the first layer of block-shaped test soil sample, and driving the lifting rod to descend to compact the test soil sample again to form the block-shaped test soil sample.

Compared with the prior art, the invention achieves the following technical effects:

the invention provides a cohesive skid band soil expansion force testing device which comprises an instrument testing pedestal, a volume adjusting and expanding device, an expansion testing cylinder, a sensing equipment assembly, a data acquisition system and a liquid injection device. The invention can realize the expansive force test of the cohesive slipband soil under different physical attribute state conditions and environmental state conditions, including the axial expansive force and the annular expansive force, test data is recorded and stored by the data acquisition system, the test precision is higher, the test conditions are simpler and more, the number of test attribute objects is more, and the invention has theoretical basis application value for the research of landslide starting mechanics.

The cohesive synovial band soil expansive force testing method is implemented based on the cohesive synovial band soil expansive force testing device, testing accuracy is higher, testing conditions are simpler and more, testing attribute objects are more, and the method has theoretical basic application value for landslide starting mechanics mechanism research.

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 schematic overall structure diagram of a cohesive skid band soil expansion force testing device disclosed by the embodiment of the invention;

fig. 2 is a schematic view of an assembly structure between a hollow straight cylinder and a lifting rod fixing bolt in the cohesive slipband soil expansion force testing device disclosed by the embodiment of the invention;

FIG. 3 is a schematic structural view of a hollow straight cylinder in the device for testing soil expansion force of the sticky slipband disclosed by the embodiment of the invention;

FIG. 4 is an axial cross-sectional view of a hollow straight cylinder in the device for testing the expansive force of cohesive slipband soil disclosed in the embodiment of the invention;

FIG. 5 is a schematic diagram illustrating a first view of a fixing bolt of a lifting rod in the device for testing soil expansion force of a cohesive skid band according to an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a second perspective view of a fixing bolt of a lifting rod in the device for testing soil expansion force of a cohesive skid band according to an embodiment of the present invention;

FIG. 7 is a schematic view of a connecting structure of a lifting rod and a mounting disc in the cohesive zona-slip soil expansive force testing device disclosed by the embodiment of the invention;

FIG. 8 is a bottom view of FIG. 7;

FIG. 9 is a schematic structural diagram of a narrow view port of an expansion testing cylinder in the cohesive slipband soil expansion force testing device disclosed in the embodiment of the present invention;

FIG. 10 is a cross-sectional view taken along line D-D of FIG. 9;

FIG. 11 is a schematic view of a perspective glass panel;

FIG. 12 is a schematic structural diagram illustrating a mounting hole of an expansion testing cylinder in the cohesive zonal soil expansion force testing apparatus according to an embodiment of the present disclosure;

FIG. 13 is a cross-sectional view F-F of FIG. 12;

FIG. 14 is a schematic view of an overall structure of a hollow screw in the device for testing soil expansion force of the sticky slipband according to the embodiment of the present invention;

FIG. 15 is a schematic view of a half-body structure of a hollow screw in the device for testing expansive force of cohesive slippery band soil disclosed in the embodiment of the present invention;

FIG. 16 is an axial view of a half-body structure of a hollow screw in the device for testing expansive force of soil in a viscous slide band, according to the embodiment of the present invention;

FIG. 17 is a schematic structural diagram of a bottom plate of an expansion testing cylinder in the cohesive slipband soil expansion force testing device disclosed in the embodiment of the present invention;

FIG. 18 is a sectional view taken along line G-G of FIG. 17;

FIG. 19 is a schematic structural diagram of an upper honeycomb backing plate in the cohesive slipband soil expansive force testing device disclosed in the embodiment of the invention;

FIG. 20 is a cross-sectional view taken along line I-I of FIG. 19;

FIG. 21 is a schematic structural view of a hollow straight cylinder in the device for testing soil expansion force of a sticky slipband according to an embodiment of the present invention;

fig. 22 is a J-J sectional view of fig. 21.

Wherein the reference numbers are:

1. a bearing table; 2. a laboratory bench; 3. an anchor screw; 4. a support rod; 5. a top plate; 6. a nut; 7. a hollow straight cylinder; 8. a lifter fixing bolt; 9. a lifting rod; 10. installing a disc; 11. expanding the test cylinder; 12. a see-through glass plate; 13. a slit viewport; 14-1, hollow screws; 14-2, mounting holes; 15. leveling a support rod; 16. a level gauge; 17-1, a tray; 17-2, an upper piston rod; 17-3, arranging a honeycomb base plate; 17-4, steel balls; 18. a permeable stone slab; 19. testing a soil sample; 20-1, fixing a cap; 20-2, hollow cylinder; 20-3, plugging and sealing; 21. a liquid inlet; 22. a liquid outlet; 23. a pressure sensor; 24. a dial indicator; 25. a liquid injection device; 26. a data acquisition system; 27. a notebook computer.

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 making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

The invention aims to provide a cohesive sliding strip soil expansive force testing device which can realize the expansive force testing of cohesive sliding strip soil under different physical attribute state conditions and environmental state conditions, fills the gap of the prior related technology and can solve the problem that the expansive force testing device capable of adjusting different physical attribute state conditions and environmental state conditions simultaneously is lacked in the prior art.

The invention further aims to provide a cohesive sliding strip soil expansion force testing method based on the cohesive sliding strip soil expansion force testing device.

In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description thereof.

Example one

As shown in fig. 1 to 10, the present embodiment provides a device for testing expansive force of cohesive soil in a slide strip, which mainly includes an instrument testing pedestal, an expansion testing cylinder 11, a volume adjusting and expanding device, a sensing device assembly, a liquid injection device 25, and a data acquisition system 26. Wherein:

the instrument test pedestal comprises a bearing table 1 and an experiment table 2, a surface mounting experiment table 2 is arranged on the bearing table 1, the bearing table 1 and the experiment table 2 are separated from each other to provide different functional effects, the bearing table 1 is used for keeping the center of gravity of the whole device stable, the experiment table 2 provides a stable installation and a test platform for the expansion test cylinder 11, the bearing table 1 and the experiment table 2 are fixed together through anchoring screws 3, four corners of the experiment table 2 are support rods 4, the upper ends of the four support rods 4 are connected with a top plate 5, the top plate 5 is fixed through nuts 6, the top plate 5 can fix a lifting rod 9 (for describing the lifting rod 9 below) in the volume adjusting and expansion device, and the auxiliary function of constant volume in the expansion test process is achieved.

The volume adjustment and expansion device includes a drive mechanism, an upper piston assembly for testing axial expansion forces, which may also be referred to as an "expansion piston", and a lower piston assembly. The upper piston assembly comprises a tray 17-1, a piston rod 17-2, an upper honeycomb backing plate 17-3 and steel balls 17-4, the tray 17-1 is in contact with the axial expansion force detection device, the length of the piston rod 17-2 can be replaced according to the volume requirement of a test object, so that the expansion force and the expansion rate of the cohesive glenoid soil under the condition of different volume physical properties are tested, the upper honeycomb backing plate 17-3 is a disc backing plate through which water flow can smoothly pass, four circular holes are formed in the middle of the upper honeycomb backing plate, grooves for mounting the steel balls 17-4 are formed in the front, the back, the left and the right of the periphery of the upper honeycomb backing plate 17-3 respectively, the steel balls 17-4 can reduce the friction force between the upper honeycomb backing plate 17-3 and the wall of the expansion test cylinder 11 in the process of water absorption and expansion of the test soil sample 19, and reduce the experimental error, and a circular water permeable stone plate 18 is arranged below the upper honeycomb backing plate; the lower piston assembly has the same structure as the upper piston assembly, is arranged at the bottom of the expansion testing cylinder 11, and can check the water saturation gravity and the axial expansion force of the testing soil sample 19; the expansion testing cylinder 11, the upper honeycomb backing plate 17-3 and the driving mechanism cooperate to achieve the compaction function of testing the soil sample at a predetermined dry density.

Further, the actuating mechanism essence of this embodiment is a elevating gear, it includes hollow straight section of thick bamboo 7 and lifter 9, hollow straight section of thick bamboo 7 directly adopts spot welding mode firmly to fix together with roof 5, in order to make the inflation test in-process keep the constant volume unchangeable, hollow straight section of thick bamboo 7 all around, left and right sides lateral wall internal thread connection lifter fixed screw 8, rotatory screwing up lifter fixed screw 8 can make lifter 9 keep motionless, can realize the free expansive force of stickness smooth area soil after unscrewing lifter fixed screw 8, the expansion rate test, lifter 9 lower extreme is provided with installation disc 10, a horizontal centering appearance is settled to installation disc 10 upper surface, spirit level 16, guarantee that lifter 9 is in the vertical position state in the test process, installation disc 10 also provides a stable platform for the installation of axial expansion force detection device. The axial expansion force detection device positioned at the top is arranged on the lower surface of the mounting disc 10 and used for being in direct contact with the top end of the piston rod 17-2 when the piston rod 17-2 is pressed downwards or the piston rod 17-2 rises under the action of the axial expansion force of the soil sample so as to detect the axial expansion force borne by the upper piston assembly.

The bottom plate of the expansion testing cylinder 11 is connected with the experiment table 2 through the leveling support rods 15, the bottom ends of the leveling support rods 15 are in threaded connection with the experiment table 2, and the horizontal position of the expansion testing cylinder 11 can be changed by rotating one or more leveling support rods 15 until the air bubbles of the level gauge 16 on the upper surface of the expansion testing cylinder 11 are centered. A water level rising height observation slit view port 13 is formed in the left side of the expansion test cylinder 11, a perspective glass plate 12 is arranged in the slit view port 13 to isolate the leakage of the test soil sample 19, and the perspective glass plate 12 can be a strip-shaped toughened curved glass; the water level rise can be observed in real time through the slit viewport 13. Mounting holes 14-2 of a circumferential expansion force detection device and a temperature detection device are formed in the right side of the expansion testing cylinder 11, the inner end of each mounting hole 14-2 is communicated with a cylinder cavity of the expansion testing cylinder 11, the inner end of each mounting hole 14-2 is used for mounting the detection device, the outer end of each mounting hole is in threaded connection with a hollow screw 14-1, and the hollow screw 14-1 plays a role in plugging the mounting hole 14-2, so that water flow in the expansion testing cylinder 11 is prevented from leaking outwards; meanwhile, the hollow screw 14-1 also plays a role of axially jacking the detection device to prevent the detection device from shaking in the mounting hole. The hollow screw 14-1 is formed by butting two half hollow screws, and a data line of the detection device corresponding to the mounting hole 14-2 is embedded in a hole cavity formed by butting the two half hollow screws. Among them, the mounting hole 14-2 is preferably provided with three, one or two of which are used for mounting the circumferential expansion force detection device, and the rest of which are used for mounting the temperature detection device.

A piston rod movable round hole is formed in the center of a cylinder bottom plate of the expansion testing cylinder 11, a lower piston rod of a lower piston assembly penetrates through the piston rod movable round hole, the piston rod movable round hole and the piston rod movable round hole are sealed through a universal plug seal 20-3, the universal plug seal 20-3 is sleeved in the piston rod movable round hole, one end of the universal plug seal is a hollow cylinder 20-2, and the other end of the universal plug seal is fixed on the cylinder bottom plate of the expansion testing cylinder 11 through a fixing cap 20-1 through bolts. The outer wall of lower piston rod closely laminates with the inner wall of general stopper seal 20-3, and the bottom of lower piston rod links to each other with laboratory bench 2 through another axial expansive force detection device, and the top of lower piston rod is located the barrel cavity of inflation test drum 11 to link to each other with honeycomb backing plate down, when honeycomb backing plate pressurized down, axial expansive force detection device owing to with the bottom direct contact of lower piston rod, can measure the axial expansive force that whole lower piston assembly received. When the levelness of the expansion test cylinder 11 is adjusted by the leveling bracket rod 15, the expansion test cylinder 11 moves up and down with respect to the lower piston rod. A liquid inlet 21 is formed in the bottom of the side wall of the expansion testing cylinder 11, a liquid outlet 22 is formed in the side wall of the top of the expansion testing cylinder 11, the liquid inlet 21 and the liquid outlet 22 are both arranged along the radial direction of the expansion testing cylinder 11, and a water flow circulation channel is formed between the liquid inlet 21 and the liquid outlet 22.

The sensing equipment assembly mainly comprises the axial expansion force detection device, a circumferential expansion force detection device, a temperature detection device, a dial indicator 24 and a level gauge 16, wherein the axial expansion force detection device is divided into two parts, one part is positioned on the installation disc 10 and is used for being contacted with the top end of the upper piston rod, the other part is positioned on the experiment table 2 and can be kept to be contacted with the bottom end of the lower piston rod, the circumferential expansion force detection device and the temperature detection device are simultaneously installed on the side wall of the expansion testing cylinder 11 and can realize synchronous monitoring and recording, the dial indicator 24 is fixed on the support rod 4, each part in the sensing equipment assembly is in communication connection with a data acquisition system 26, the data acquisition system 26 can record the axial expansion force, the circumferential expansion force and the temperature change condition generated by water absorption and expansion of the cohesive zonal soil in real time, and simultaneously records the water saturation weight of the testing soil sample 19 recorded by the lower sensor. The axial expansion force detection device, the annular expansion force detection device and the temperature detection device are preferably an axial expansion force sensor, an annular expansion force sensor and a temperature sensor respectively, and the two axial expansion force sensors can be pressure sensors 23.

The liquid injection device 25 is a water injection seepage device, and is loaded with distilled water, and is provided with a heating device, a valve and the like, wherein the heating device can control the temperature of water flow discharged by the liquid injection device 25, such as a water heater; a valve, such as a solenoid valve, can control the water flow rate. The heating device and the valve are all in the prior art and are not described in detail herein. The testing of the expansive force and the expansion rate of the cohesive synovial fluid soil in the pressurizing environment state can be realized by adjusting the water flow speed of the liquid injection device 25, and the testing of the expansive force and the expansion rate of the cohesive synovial fluid soil in different temperature environment states can be realized by adjusting the water flow temperature.

The data acquisition system 26 can be connected to a notebook computer 27 in a communication manner, and the notebook computer 27 stores, further processes and analyzes the data acquired by the data acquisition system 26.

The cohesive slipband soil expansive force testing device of the embodiment specifically is an expansive force testing device of cohesive slipband soil under different physical attribute state conditions and environmental state conditions, and the testing device can change different physical attribute state conditions such as clay mineral component content ratio, test piece size, initial moisture content and dry density of a test piece, and can provide environmental state conditions such as different pressures, different temperatures. The method for testing the cohesive sliding strip soil expansive force by adopting the cohesive sliding strip soil expansive force testing device specifically comprises the following steps:

step 1, firstly, placing a permeable stone slab 18 on a lower honeycomb base plate at the bottom of an expansion testing cylinder 1, smearing vaseline on the inner wall of the expansion testing cylinder 1, wherein the preparation method of the testing soil sample is a static pressure method, in order to ensure the uniformity of the testing soil sample, compacting the testing soil sample in 2 layers, weighing the testing soil sample with target dry density mass by using a precision electronic balance, pouring the testing soil sample into the expansion testing cylinder 1, then sequentially loading the permeable stone slab 18 and an upper honeycomb base plate 17-3 above the testing soil sample, configuring a tray 17-1 and an upper piston rod 17-2 on the upper honeycomb base plate 17-3, removing a mounting disc 10 and an axial expansion force sensor at the bottom of a lifting rod 9, driving the lifting rod 9 to descend to drive the upper honeycomb base plate 17-3 to be pressed downwards so as to compact the soil sample to an assumed dry density, using the height change of the testing sample as a verification standard, observing the compacted height of the poured soil sample through a left view port 13, and finishing the compaction work of the first layer of the sample when the height of the testing soil sample stays at a scale position of 6 cm; the test soil sample of the same target dry density mass is then poured and the same compaction method is used to obtain the final test soil sample 19 in block form.

Step 2, after the loaded test soil sample 19 reaches the assumed experimental conditions, the mounting disc 10 and the axial expansion force sensor are mounted at the bottom of the lifting rod 9 again, then the lifting rod 9 freely descends to be tightly connected with the tray 17-1 at the top of the upper piston rod 17-2, overlying pressure in the process has certain influence on the test soil sample 19, mainly showing that parameters such as the volume, the porosity and the like of the test soil sample are reduced, lateral pressure is caused by the overlying pressure in the process, and the lateral pressure is test errors of the expansion force test, so that the test soil sample needs to be placed for a period of time, after the detection values of the relevant axial expansion force sensor, the annular expansion force sensor, the temperature sensor and the like are stable, the lifting rod fixing bolt 8 is tightened to fix the height position of the lifting rod 9 at the moment, and at the moment, the interval between the upper honeycomb base plate 17-3 and the lower honeycomb base plate is unchanged, and the purpose of constant volume of the test is achieved.

Step 3, after the expansion testing cylinder 11 is statically calibrated, in order to accurately test the quantitative result of the expansion force of the soil sample, the axial pressure and the circumferential pressure generated in the static calibration process need to be cleared, the step is called as instrument zero setting, and in addition, the zero setting of the related dial indicator 24 only needs to take the staying reading of the statically calibrated cylinder as initial data.

And 4, after the liquid injection device 25 is filled with distilled water, heating the water temperature of the liquid injection device to a set temperature, setting a water outlet rate, connecting the water outlet rate with a liquid inlet 21 at the bottom of the expansion testing cylinder 11 after the water outlet rate of the water outlet pipe is stable, starting a viscous slide-band soil expansion force testing experiment, allowing water to sequentially pass through the circular holes of the lower honeycomb base plate and the bottom permeable stone plate 18 and enter a testing soil sample 19, allowing the water to seep out of the circular holes of the top permeable stone plate 18 and the upper honeycomb base plate 17-3 and flow out of a liquid outlet 22, and collecting water flowing out of the water outlet pipe independently. The test of the cohesive sliding band soil expansion force under different water temperature environmental conditions can be realized by adjusting the set temperature of the liquid injection device 25, and the test of the cohesive sliding band soil expansion force under different water pressure environmental conditions can be realized by adjusting the water injection seepage speed. The distilled water in the liquid injection device 25 can be heated by arranging a special heater, and the water temperature heating range is 20-50 ℃.

And 5, collecting and storing related data parameters by a data acquisition system 26, recording the water level rising height of the slit viewport 13 on the left side in real time by using a camera, monitoring the water gravity generated by water flow penetrating through the upper honeycomb backing plate, the lower honeycomb backing plate and the permeable stone plate 18 by using a pressure sensor 23 on the experiment table 2, monitoring the annular expansion force of the viscous sliding band soil by using an annular expansion force sensor in the mounting hole 14-2 on the right side, monitoring the corresponding soil sample temperature in real time by using a temperature sensor in the mounting hole 14-2 on the right side, recording and monitoring the axial expansion force generated after the soil sample reaches a water saturation state by using an axial expansion force sensor on the upper part until the expansion force data detected by the axial expansion force sensor changes by a range less than 0.1kPa within 2h, and determining the soil sample to be stable.

And 6, after the step 5 is successfully completed, loosening the lifting rod fixing bolt 8 to enable the axial expansion force generated by the test soil sample 19 to drive the parts such as the permeable stone plate 18 at the top, the upper honeycomb base plate 17-3, the upper piston rod 17-2, the mounting disc 10, the lifting rod 9 and the like to move upwards, enabling the test soil sample 19 to freely expand under the lateral limit condition, recording monitoring data of various attribute objects in real time, and determining that the data are stable when the variation range of all the expansion force data is smaller than 0.1kPa within 2 h.

And 7, after the step 6 is successfully completed, closing a switch of the liquid injection device 25 and pulling out a water outlet pipe on the liquid injection device 25, draining water flowing out of a liquid inlet 21 at the bottom of the expansion testing cylinder 11 by a rubber pipe and independently collecting the water, enabling the lifting rod 9 to be in an active state, monitoring relevant data of the expansion force in real time by the data acquisition system 26, and determining that the expansion force data is stable when the change amplitude of the expansion force data is smaller than 0.1kPa within 2 hours after all water in the soil sample 19 to be tested flows out.

Therefore, the technical scheme particularly relates to a cohesive zonal soil expansion force testing device and a testing method formed by sliding a slope controlled by a coal-based stratum, an alumina texture layer and a weak stratum mainly containing expansive minerals along the weak stratum. Compared with the prior art, the technical scheme can realize the expansive force test of the cohesive zonal soil under different physical attribute state conditions and environment state conditions, comprises the axial expansive force and the annular expansive force, adopts the pressure sensor, the temperature sensor and the dial indicator to record test data in real time and the data acquisition system to record and store the test data, and is the expansive force tester integrating the advantages of higher test precision, simpler and more test conditions, more test attribute objects and the like. Compared with the prior art, the technical scheme has the following specific beneficial effects:

(1) The technical scheme is provided with the volume adjusting and expanding device which is provided with a lifting rod structure, a detachable connection mode is adopted between the lifting rod and an installation disc of the lifting rod, the lifting rod and the installation disc are detached from each other, a compaction function can be provided for the fact that a cohesive skid soil test soil sample reaches a preset dry density, a water level rise height slit viewport on the side surface of an expansion test cylinder is assisted to observe compaction thickness, and meanwhile, the test process and steps of the test device are simpler and more convenient due to the separation design function; the technical scheme can also realize the expansive force test of the cohesive slipband soil under the constant volume condition and the free expansion condition at the same time, and the expansive force test under different volume conditions can be controlled by adjusting the lifting rod fixing bolt.

(2) This testing arrangement can realize the expansive force test of stickness slipband soil under the different physical attribute state conditions, can change the clay mineral component content ratio of test soil sample, compaction size of a dimension, initial moisture content and dry density etc. adopt axial expansive force sensor, hoop expansive force sensor, temperature sensor, amesdial to gather experimental data in real time, and degree of automation is high, has changed in the past test technique can't realize the test requirement of different physical attribute state conditions.

(3) This testing arrangement can also realize the expansive force test of stickness slipband soil under the different environmental condition, can change water velocity and change water injection pressure, changes rivers temperature and changes ambient temperature, and this testing arrangement's functionality has obtained the promotion that is showing, and the test attribute object becomes more.

(4) This testing arrangement can observe water injection seepage back stickness draw tape soil hoop expansibility hysteresis effect, observes the water level rise through the slit viewport to combine hoop expansibility, the stable change experimental data, the hysteresis effect between the real-time contrast two is unable to realize inside the technique in the past.

(5) This testing arrangement can realize the expansive force test of stickness slipband soil under the drainage condition, in the inflation test process of accomplishing a test soil sample, in order to as much as possible obtain test attribute experimental data, can realize the drainage condition test through adjusting priming device, pulls out the outlet pipe promptly, can realize.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the claim concerned.

The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the 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 (10)

1. The utility model provides a stickness draw soil expansibility testing arrangement which characterized in that includes:

the device comprises a test pedestal, wherein an expansion test cylinder is arranged on the test pedestal, a liquid inlet is formed in the bottom of the expansion test cylinder, and a liquid outlet is formed in the top of the expansion test cylinder;

the volume adjusting and expanding device comprises a driving mechanism, an upper piston assembly and a lower piston assembly, the upper piston assembly comprises an upper honeycomb base plate and an upper piston rod, the upper honeycomb base plate is arranged at the upper part of a cylinder cavity of the expansion testing cylinder, and the upper piston rod is connected to the upper surface of the upper honeycomb base plate; the lower piston assembly comprises a lower honeycomb base plate and a lower piston rod, the lower honeycomb base plate is arranged at the lower part of a cylinder cavity of the expansion testing cylinder, the lower piston rod is connected to the lower surface of the lower honeycomb base plate, a sample space for containing a testing soil sample is formed among the upper honeycomb base plate, the lower honeycomb base plate and the cylinder wall of the expansion testing cylinder, at least one of the upper piston rod and the lower piston rod is connected with the driving mechanism, and the driving mechanism can enable the upper honeycomb base plate and the lower honeycomb base plate to be close to or far away from each other so as to adjust the volume of the sample space; permeable stone slabs are arranged between the test soil sample and the upper honeycomb base plate and between the test soil sample and the lower honeycomb base plate so as to intercept the test soil sample in the sample space in the test process;

the liquid injection device is connected with the liquid inlet and is used for injecting test liquid into the expansion test cylinder, and the temperature and the injection flow rate of the test liquid are adjustable;

the sensing equipment assembly comprises an axial expansion force detection device, an annular expansion force detection device and a temperature detection device, and the annular expansion force detection device and the temperature detection device are arranged on the expansion test cylinder; the axial expansion force detection device can detect the expansion force applied to the upper piston assembly and the lower piston assembly;

and the data acquisition system is in communication connection with the liquid injection device, the driving mechanism, the axial expansion force detection device, the annular expansion force detection device and the temperature detection device.

2. The cohesive skid soil expansive force testing device of claim 1, wherein said testing stand comprises:

a bearing table;

the experiment table is arranged on the upper surface of the bearing table;

the device comprises leveling support rods, wherein the leveling support rods are arranged on the upper surface of the experiment table and are uniformly provided with a plurality of leveling support rods, the bottom ends of all the leveling support rods are in threaded connection with the experiment table, and the expansion test cylinder is arranged above the leveling support rods and is connected with the top ends of all the leveling support rods.

3. The cohesive skid soil expansive force testing device of claim 2, wherein the lower piston rod is arranged through the bottom of the expansion testing cylinder, and the lower piston rod and the expansion testing cylinder are sealed by a flooding plug seal which is fixed on the bottom of the expansion testing cylinder through a fixing cap; the bottom end of the lower piston rod is connected with the experiment table through the axial expansion force detection device, and the top end of the lower piston rod is connected with the lower honeycomb base plate;

the top end of the upper piston rod is connected with the driving mechanism through the axial expansion force detection device.

4. The cohesive skid soil expansive force testing device of claim 3, further comprising a top plate, wherein the top plate is supported on the experiment table through a support rod and is positioned above the expansion testing cylinder; the drive mechanism includes:

the hollow straight cylinder is arranged on the upper surface of the top plate;

the lifting rod is slidably sleeved in the hollow straight cylinder, the bottom end of the lifting rod penetrates through the top plate, and the top end of the lifting rod is used for being connected with a lifting power source;

the upper surface of the mounting disc is detachably connected with the bottom end of the lifting rod, the top end of the upper piston rod is connected with a tray, and the lower surface of the mounting disc is detachably connected with the tray; the mounting disc is provided with the axial expansion force detection device which can detect the expansion force borne by the upper piston assembly;

the lifting rod fixing bolt penetrates through the side wall of the hollow straight cylinder and is in threaded connection with the side wall of the hollow straight cylinder, and the tail of the lifting rod fixing bolt can stretch into the hollow straight cylinder and is tightly pressed against the lifting rod.

5. The cohesive sliptape soil expansive force testing device of any one of claims 1 to 4, wherein a slit viewing port extending along the axial direction of the expansive testing cylinder is formed in the side wall of the expansive testing cylinder, and the slit viewing port is communicated with the cylinder cavity of the expansive testing cylinder; a perspective glass plate is hermetically arranged in the slit sight opening and used for observing the change of the liquid level in the expansion testing cylinder; the outside of slit viewport still is provided with the liquid level scale.

6. The cohesive slippery band soil expansive force testing device of claim 5, wherein the sensing equipment assembly further comprises an image acquisition device, a dial indicator and a level gauge, the image acquisition device, the dial indicator and the level gauge are all in communication connection with the data acquisition system, wherein the image acquisition device is used for recording the liquid level rising height through the slit view port in real time, the dial indicator is arranged on the support rod, and the level gauges are arranged on the tops of the mounting disc and the expansion testing cylinder.

7. The cohesive skid band soil expansive force testing device of claim 5, wherein a side wall of the expansion testing cylinder opposite to the slit view port is provided with a plurality of mounting holes, and all the mounting holes are distributed along the axial direction of the expansion testing cylinder; any one of the mounting holes is communicated with the cylinder cavity of the expansion testing cylinder, the inner ends of part of the mounting holes are provided with the annular expansion force detection device, and the inner ends of the rest mounting holes are provided with the temperature detection device; the outer end of any one of the mounting holes is in threaded connection with a hollow screw so as to plug the mounting hole; the hollow screw is formed by butt joint of two half hollow screws, and a data line of the annular expansion force detection device or the temperature detection device is embedded in an inner cavity of the hollow screw.

8. The cohesive tyre soil expansive force testing device as claimed in any one of claims 1 to 4, wherein the peripheries of the upper honeycomb backing plate and the lower honeycomb backing plate are provided with grooves, a plurality of steel balls are embedded in the grooves, and the peripheries of the upper honeycomb backing plate and the lower honeycomb backing plate are in sliding fit with the inner cylinder wall of the expansion testing cylinder through the steel balls.

9. A method for testing cohesive slipband soil expansion force by using the cohesive slipband soil expansion force testing device of claim 4, which comprises the following steps:

step 1, paving the permeable stone slab on the upper honeycomb base plate, placing a test soil sample with target dry density quality into the expansion test cylinder, dismantling the installation disc, and driving the lifting rod to descend to compact the test soil sample to form a block-shaped test soil sample;

step 2, sequentially placing the permeable stone slabs and the upper honeycomb base plates connected with the upper piston rods and the trays above the blocky test soil samples, installing the installation disks, driving the lifting rods to descend until the installation disks are connected with the trays, and fixing the positions of the lifting rods;

step 3, resetting the axial expansion force detection device, the annular expansion force detection device and the temperature detection device;

step 4, injecting a test liquid into the expansion test cylinder, and starting a cohesive slipband soil expansion force test experiment;

step 5, collecting and storing the data of the sensing equipment assembly through the data acquisition system;

step 6, loosening the lifting rod to enable the axial expansion force generated by the massive test soil sample to drive the upper honeycomb base plate to move upwards, and simultaneously recording the axial expansion force, the annular expansion force and the temperature of the massive test soil sample after imbibition in real time through the sensing equipment assembly;

and 7, discharging the test liquid in the expansion test cylinder through the liquid inlet.

10. The method for testing soil expansive force of the cohesive skid strip of claim 9, wherein in the step 1, the step of pressing the massive test soil sample comprises the following steps:

step 11, placing a test soil sample with target dry density quality into the expansion test cylinder, driving the lifting rod to descend to compact the test soil sample, and forming a first layer of block-shaped test soil sample;

and step 12, placing the test soil sample with the same target dry density quality above the first layer of block-shaped test soil sample, and driving the lifting rod to descend to compact the test soil sample again to form the block-shaped test soil sample.

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