CN114136811B - Large-scale multifunctional soil and structure interface shearing device and application method thereof - Google Patents
Large-scale multifunctional soil and structure interface shearing device and application method thereof Download PDFInfo
- Publication number
- CN114136811B CN114136811B CN202111483759.6A CN202111483759A CN114136811B CN 114136811 B CN114136811 B CN 114136811B CN 202111483759 A CN202111483759 A CN 202111483759A CN 114136811 B CN114136811 B CN 114136811B
- Authority
- CN
- China
- Prior art keywords
- soil
- pile
- tank body
- model pile
- soil sample
- 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.)
- Active
Links
- 239000002689 soil Substances 0.000 title claims abstract description 238
- 238000010008 shearing Methods 0.000 title claims abstract description 88
- 238000000034 method Methods 0.000 title claims abstract description 50
- 238000006073 displacement reaction Methods 0.000 claims abstract description 137
- 238000012360 testing method Methods 0.000 claims abstract description 63
- 230000007246 mechanism Effects 0.000 claims abstract description 55
- 238000003825 pressing Methods 0.000 claims abstract description 15
- 230000008569 process Effects 0.000 claims description 24
- 238000007906 compression Methods 0.000 claims description 23
- 230000006835 compression Effects 0.000 claims description 21
- 230000003068 static effect Effects 0.000 claims description 21
- 229910000831 Steel Inorganic materials 0.000 claims description 13
- 238000007667 floating Methods 0.000 claims description 13
- 239000010959 steel Substances 0.000 claims description 13
- 238000013500 data storage Methods 0.000 claims description 11
- 238000009434 installation Methods 0.000 claims description 11
- 239000000565 sealant Substances 0.000 claims description 11
- 238000004088 simulation Methods 0.000 claims description 10
- 230000035515 penetration Effects 0.000 claims description 9
- 230000000712 assembly Effects 0.000 claims description 8
- 238000000429 assembly Methods 0.000 claims description 8
- 239000002775 capsule Substances 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 6
- 238000004806 packaging method and process Methods 0.000 claims description 6
- 238000007789 sealing Methods 0.000 claims description 3
- 230000035945 sensitivity Effects 0.000 claims description 3
- 239000000463 material Substances 0.000 description 11
- 210000005056 cell body Anatomy 0.000 description 7
- 238000002360 preparation method Methods 0.000 description 7
- 230000008901 benefit Effects 0.000 description 6
- 125000004122 cyclic group Chemical group 0.000 description 6
- 238000005259 measurement Methods 0.000 description 6
- 230000003993 interaction Effects 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000005464 sample preparation method Methods 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0001—Type of application of the stress
- G01N2203/0003—Steady
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0025—Shearing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/022—Environment of the test
- G01N2203/023—Pressure
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/025—Geometry of the test
- G01N2203/0258—Non axial, i.e. the forces not being applied along an axis of symmetry of the specimen
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/026—Specifications of the specimen
- G01N2203/0262—Shape of the specimen
- G01N2203/0274—Tubular or ring-shaped specimens
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/026—Specifications of the specimen
- G01N2203/0298—Manufacturing or preparing specimens
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0676—Force, weight, load, energy, speed or acceleration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/067—Parameter measured for estimating the property
- G01N2203/0682—Spatial dimension, e.g. length, area, angle
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a large-scale multifunctional soil and structure interface shearing device, wherein a power mechanism is arranged on a supporting structure, a shearing tank comprises a tank body, an upper mounting opening and a lower mounting opening are arranged on the tank body, a bag body is arranged in the tank body, two ends of the bag body extend to the upper mounting opening and the lower mounting opening respectively, a soil sample is filled in the bag body, two ends of a model pile penetrate through the soil sample, and detachable fixing components are respectively arranged at the upper mounting opening and the lower mounting opening of the tank body; a pulling and pressing sensor is hinged between the end part of the output rod of the power mechanism and the top end of the model pile; the top end and the bottom end of the model pile are respectively provided with a first high-precision displacement meter and a second high-precision displacement meter, and a third high-precision displacement meter for measuring the radial displacement of the soil sample is arranged in the tank body. The invention also discloses a use method of the large-scale multifunctional soil and structure interface shearing device. The invention can solve the problem that the existing soil sample and structure interface shear test cannot meet the requirements of different types of shear tests.
Description
Technical Field
The invention relates to the technical field of geotechnical test, in particular to a large-scale multifunctional soil and structure interface shearing device and a using method thereof.
Background
The problem of interaction between soil samples and structures has been an important issue for long-term research in the engineering field. The contact of the soil sample and the structure relates to various aspects such as soil mechanics, foundation engineering, supporting engineering, bridge engineering, tunnel engineering and the like, such as contact of a sheet pile wharf structure and the soil sample, contact of a pile foundation and the soil sample, contact of a retaining wall and the soil sample, contact of a dam and the soil sample, contact of a tunnel lining and the soil sample and the like. The method relates to two materials with larger mechanical property difference, and when the two materials are subjected to external load, the deformation difference of the two materials causes the contact surface of the soil sample and the structure to generate interaction force, so that discontinuous contact phenomena such as dislocation, slippage, cracking and the like are generated between the soil sample and the structure.
Meanwhile, in recent years, pile structures are widely applied to bridge engineering, foundation engineering, supporting engineering and port engineering construction, such as a port zhu-ao-da bridge which is known as one of the 'zhu-mulamban peak' of bridge industry and 'seven-dada-odd-trace' of modern world, and a Beijing daxing airport which is known as the first of 'seven-dada-odd-trace of new world', which are widely applied to pile foundations. Taking foundation engineering as an example, the cost of pile foundation in civil high-rise building engineering can be up to 30% of the total cost of the engineering. The current pile foundation design is mainly estimated by adopting an empirical formula and numerical simulation, and the on-site static load test is combined to verify whether the bearing capacity of the pile foundation meets the requirement, so that the design value of the pile foundation is often larger than the actual requirement of engineering, thereby generating the waste of engineering materials, and accurately calculating the pile-soil interaction force is the key for solving the problem. Therefore, the contact mechanical property of the soil sample and the pile is revealed, the pile-soil interaction mechanism is well defined, the accuracy of pile foundation bearing capacity and the calculation of the horizontal force resisting by the supporting pile structure is improved, the engineering material waste generated by pile structure application is reduced, and the economic benefit of the pile foundation in engineering application is improved.
However, the study of the mechanical properties between the soil sample and the structure is premised on a precise geotechnical test instrument. The existing soil sample and structure interface shearing equipment is mainly an interface shearing instrument, but the equipment has the defects of lower simulated stress state, single stress path, uncertain main stress direction, reduced contact area of the soil sample and the structure along with the increase of shearing displacement and the like. Meanwhile, the conventional shearing equipment is small in size, the soil sample preparation is difficult, the relative density control precision of the soil sample is low, and the accuracy of the soil sample preparation is a key for ensuring the accuracy of measured test data. In addition, the shearing displacement of the conventional shearing equipment is relatively small, and the problems of large deformation of interface contact and the requirement of cyclic load research, such as earth-rock dams, static pressure piles and the like, cannot be met. Therefore, the device for testing the shear of the soil sample and the structure interface is developed to meet the test requirements of high stress state, complex stress path, large deformation problem of interface contact, cyclic load, improvement of soil sample preparation and control precision and the like. Thus, reliable data is provided for further defining the mechanical properties of the contact interface between the soil sample and the structure.
Disclosure of Invention
The invention aims to provide a large-scale multifunctional soil and structure interface shearing device and a use method thereof, which are used for solving the problems that in the traditional soil sample and structure interface shearing test, the soil sample is difficult to prepare, the height-diameter ratio of the soil sample is inconvenient to adjust, the large deformation of pile-soil contact cannot be met, and the requirements of different types of shearing tests cannot be met.
In order to solve the problems, the invention adopts the following technical scheme:
the utility model provides a large-scale multi-functional soil and structure thing interface shearing mechanism, includes bearing structure, power unit, control system and data acquisition system, and power unit installs on bearing structure, still includes the shearing jar, and the shearing jar includes the jar body, is provided with upper mounting mouth, lower mounting mouth, pressurization mouth, pressure release mouth and wire hole on the jar body, installs the cell body in the jar body, the cell body is cylindrical structure, and the both ends of cell body extend to upper mounting mouth and lower mounting mouth department respectively, and the diameter of cell body is less than the diameter of upper mounting mouth or lower mounting mouth, fills gas or liquid between cell body and the jar body inner wall, fills in the cell body has the soil sample, has placed the model stake in the soil sample, and the axial of model stake is unanimous with cell body, and the both ends of model stake run through the soil sample setting;
the upper mounting opening and the lower mounting opening of the tank body are respectively provided with a detachable fixing component, the fixing components are arranged on the tank body, a sealing structure is formed in the tank body, two ends of the bag body are respectively fixed at the fixing components, one side surface of the fixing components facing the inside of the tank body is flush with the inner surface of the tank body, and two ends of a soil sample are respectively contacted with one side surface of the fixing components facing the inside of the tank body;
The top end and the bottom end of the model pile extend out of the corresponding fixing assemblies respectively, an output rod of the power mechanism and the model pile are coaxially arranged, and a tension and compression sensor is hinged between the end part of the output rod of the power mechanism and the top end of the model pile;
the part of the top end of the model pile, which extends out of the fixing component, is provided with a first high-precision displacement meter used for measuring the axial displacement of the model pile, the part of the bottom end of the model pile, which extends out of the fixing component, is provided with a second high-precision displacement meter used for measuring the axial displacement of the model pile, the tank body is internally provided with a third high-precision displacement meter used for measuring the radial displacement of the soil sample, and the tension and compression sensor, the first high-precision displacement meter, the second high-precision displacement meter and the third high-precision displacement meter are respectively connected with a data acquisition system through wires.
Optionally, the supporting structure is a steel frame, the steel frame is a door-shaped structure, the power mechanism is an electric cylinder, the electric cylinder is vertically arranged on the steel frame, the control system is a servo control system, and the servo control system is connected with the electric cylinder.
Optionally, the fixing component comprises a flange, a backing plate, a backing ring and a cover plate, wherein the flange, the backing plate, the backing ring and the cover plate are of annular structures, the flange is detachably fixed at an upper mounting opening and/or a lower mounting opening of the tank body through bolts, a clamping step is circumferentially fixed at the top of one side of the flange, which is positioned on the inner ring, a hoop is arranged on the outer ring of the clamping step, the top end of the bag body is fixed between the clamping step and the hoop after passing through the clamping step, and the diameter of the inner ring of the flange is matched with that of the bag body;
Backing plate and backing ring all are placed on the soil sample surface and all are located the bag body inboard, and the backing ring is placed in the backing plate inner circle, backing ring inner circle and the outer week direct contact of model stake, the apron covers on backing plate and backing ring surface and can dismantle fixed connection with the ring flange through the bolt, is equipped with the clearance between the outer week of apron inner circle and model stake, and the periphery diameter of apron is greater than the diameter of backing plate.
Optionally, the axes of the measuring rods of the first high-precision displacement meter and the second high-precision displacement meter are parallel to the axis of the model pile, and the axis of the measuring rod of the third high-precision displacement meter is perpendicular to the axis of the model pile;
the periphery of the part of the top end of the model pile, which extends out of the fixing component, is fixedly connected with an upper hoop rod which is horizontally arranged, the first high-precision displacement meter is supported by an upper supporting rod, the upper supporting rod is fixed on a supporting structure, and a measuring rod of the first high-precision displacement meter is contacted with the upper hoop rod; the periphery of the part of the bottom end of the model pile, which extends out of the fixing component, is fixedly connected with a lower hoop rod which is horizontally arranged, the second high-precision displacement meter is supported by a lower supporting rod, the lower supporting rod is fixed on the ground, and a measuring rod of the second high-precision displacement meter is contacted with the lower hoop rod;
an inner supporting rod is vertically fixed in the tank body, a plurality of third high-precision displacement meters are installed on the inner supporting rod from top to bottom, and two first high-precision displacement meters and two second high-precision displacement meters are symmetrically arranged respectively.
Optionally, a first floating joint is connected between one end of the pull-press sensor and the top end of the model pile, the other end of the pull-press sensor is connected with a second floating joint, and the second floating joint is connected with the end part of an output rod of the power mechanism through a fisheye joint bearing.
Optionally, an adapter plate is mounted on a cover plate in the fixed assembly at the lower mounting opening, and a linear bearing is mounted on the adapter plate and is in sliding connection with the model pile.
Optionally, a cushion block with adjustable height is arranged between the bottom of the inner side of the bag body and the fixed component.
According to the large-scale multifunctional soil and structure interface shearing device, when a pile-soil interface shearing simulation test is carried out, the using method comprises the following steps:
step S1: a third high-precision displacement meter is arranged in the tank body, a lead of the third high-precision displacement meter is connected out from a wire outlet hole of the tank body, the wire outlet hole is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component and a bag body with the specification corresponding to the height-diameter ratio of a soil sample are selected, the fixed component is arranged at a lower mounting opening of the tank body, a flange plate and a hoop ring in the fixed component are arranged at the mounting opening of the tank body, and two ends of the bag body are respectively fixed at the corresponding flange plate through the hoop ring;
Step S2: installing a model pile, enabling two ends of the model pile to penetrate through the fixing assemblies at the two ends, and enabling the axial direction of the model pile to be consistent with the tensile direction provided by the power mechanism;
step S3: according to the test requirement, filling soil into the bag body to obtain a circular soil sample, after filling the soil, installing a backing plate, a backing plate and a cover plate in a fixing assembly at a mounting opening on the tank body, wherein during installation, the backing plate and the backing plate are both placed on the surface of the soil sample, an inner ring of the backing plate is in direct contact with the periphery of a model pile, the cover plate covers the surfaces of the backing plate and is connected with a flange plate, and a gap is arranged between the inner ring of the cover plate and the periphery of the model pile to finish packaging;
step S4: the power mechanism, the tension and compression sensor, the first high-precision displacement meter and the second high-precision displacement meter are sequentially installed, the power mechanism is connected with the control system, the tension and compression sensor, the first high-precision displacement meter, the second high-precision displacement meter and the third high-precision displacement meter are respectively connected with the data acquisition system through wires, and the data acquisition system is connected with the data storage system;
step S5: closing a valve at the pressure release opening, applying air pressure or hydraulic confining pressure to the soil sample in the tank body through the pressure opening, obtaining the soil sample confining pressure according to the measured value of the pressure gauge additionally arranged on the tank body, and then applying load to the model pile through the power mechanism to control the axial displacement of the model pile so as to realize the pile-soil interface shearing simulation;
Step S6: the displacement of the model pile and the body strain of the soil sample in the process of shearing the interface between the soil sample and the model pile can be obtained through the first high-precision displacement meter, the second high-precision displacement meter and the third high-precision displacement meter; the shearing force in the shearing process can be obtained through the pulling and pressing sensor;
step S7: and when the displacement of the model pile reaches a preset value, loading of the power mechanism can be stopped, and after the test is finished, a valve at the pressure relief opening is opened for pressure relief.
According to the interface shearing device for the large-scale multifunctional soil and the structure, when a simulation test of the static pressure pile is carried out, the interface shearing device comprises the following steps:
step S1: a third high-precision displacement meter is arranged in the tank body, a lead of the third high-precision displacement meter is connected out from a lead hole of the tank body, the lead hole is sealed by high-strength sealant after the lead hole is connected out, a fixed component and a bag body with the specifications corresponding to the height-diameter ratio of a soil sample are selected, the fixed component is arranged at a lower mounting opening of the tank body, a backing ring and a backing plate in the fixed component at the lower mounting opening are replaced by a disc-shaped whole backing plate so as to block the bottom of the soil sample, a flange plate and a hoop in the fixed component are arranged at the mounting opening of the tank body, and two ends of the bag body are respectively fixed at the corresponding flange plate through the hoops;
Step S2: according to the test requirement, filling soil into the bag body to obtain a cylindrical soil sample, after filling the soil, installing a backing ring, a backing plate and a cover plate in a fixing assembly at a mounting opening on the tank body, wherein the backing plate and the backing ring are both placed on the surface of the soil sample during installation, and the cover plate covers the surfaces of the backing plate and the backing ring and is connected with a flange plate;
step S3: closing a valve at the pressure relief opening and performing zero setting on the pressure gauge;
step S4: the method comprises the steps that a power mechanism, a pulling and pressing sensor and a model pile are sequentially installed, the model pile is installed on the upper portion of a soil sample, the axial direction of the model pile is consistent with the pulling direction provided by the power mechanism, the power mechanism is connected with a control system, the pulling and pressing sensor and end resistors in the model pile are respectively connected with a data acquisition system through wires, and the data acquisition system is connected with a data storage system;
step S5: applying air pressure or hydraulic confining pressure to the soil sample in the tank body through the pressurizing opening, obtaining the soil sample confining pressure according to the measured value of the pressure gauge arranged on the tank body, and then applying load to the model pile through the power mechanism to control the model pile to penetrate into the soil sample at a certain speed so as to realize simulation of the static pressure pile;
Step S6: in the static pile test process, pile top pressure is measured by adopting a tension and compression sensor, and end resistance in the pile pressing process is measured by adopting an end resistance meter in the model pile; simulating the proportion of end resistance and pile side friction force in the pile sinking process of the static pressure pile when different soil depths are achieved by changing the soil sample confining pressure; calculating pile body penetration depth before pile pressing, namely simulating static pile penetration depth when the difference between the soil sample height and the pile diameter 8-10 times of the model pile is 8-10 times of the pile diameter of the soil sample bottom of the model pile, and ending static pile penetration when the pile tip of the model pile is 8-10 times of the pile diameter;
step S7: and after the test is finished, opening a valve at the pressure relief opening to relieve pressure.
According to the large-scale multifunctional soil and structure interface shearing device, when the soil pressure box calibration test is carried out, the method comprises the following steps:
step S1: a third high-precision displacement meter is arranged in the tank body, a lead of the third high-precision displacement meter is connected out from a wire outlet hole of the tank body, the wire outlet hole is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component and a bag body with the specification corresponding to the height-diameter ratio of a soil sample are selected, the fixed component is arranged at a lower mounting opening of the tank body, a flange plate and a hoop ring in the fixed component are arranged at the mounting opening of the tank body, and two ends of the bag body are respectively fixed at the corresponding flange plate through the hoop ring;
Step S2: embedding a miniature soil pressure box on the model pile, and then installing the model pile in a shearing tank, so that two ends of the model pile penetrate through fixing assemblies at two ends, and the axial direction of the model pile is consistent with the axial direction of the capsule body;
step S3: according to the test requirement, filling soil into the bag body to obtain a circular soil sample, after filling the soil, installing a backing plate, a backing plate and a cover plate in a fixing assembly at an installation opening on the tank body, wherein the backing plate and the backing plate are both placed on the surface of the soil sample during installation, the inner ring of the backing plate is in direct contact with the periphery of a model pile, and the cover plate covers the surfaces of the backing plate and is connected with a flange plate to finish packaging;
step S4: after the soil sample and the model pile are packaged, closing a valve at a pressure release opening, applying air pressure or hydraulic confining pressure to the soil sample in the tank body through a pressurizing opening, comparing the reading of the pressure gauge with the pressure measured by the soil pressure box, and finally correcting the sensitivity coefficient of the soil pressure box according to the reading of the pressure gauge so as to enable the data measured by the soil pressure box to be consistent with the reading of the pressure gauge, thereby completing a calibration test of the soil pressure box;
step S5: and after the test is finished, opening a valve at the pressure relief opening to relieve pressure.
By adopting the technical scheme, the invention has the following advantages:
The shearing tank body is provided with the upper mounting opening and the lower mounting opening, and is blocked by the fixing assembly, so that a foundation is structurally provided for preparing the soil sample by adopting the rain falling method, the preparation difficulty of the soil sample is effectively reduced, and the preparation efficiency and the relative density control precision of the soil sample are remarkably improved.
According to the invention, the two ends of the bag body are respectively fixed at the fixing assembly, so that the stability of the bag body is effectively improved, the bag body is prevented from falling off in the pressurizing and shearing processes, and the setting of the base plate enables the soil sample to be completely in the pressure action range of the shearing tank, so that the influence of the boundary effect at the two ends of the soil sample on the stress level of the soil sample is effectively reduced.
The shearing device disclosed by the invention is used for measuring displacement of two ends of the model pile, so that not only can the displacement of the model pile be measured, but also the extension or compression of the model pile under the action of shearing force can be measured, and the calculation precision of the shearing force of the contact interface between a soil body and a structure can be further improved.
According to the invention, the backing ring made of acrylic material is in contact with the model pile, so that the advantage of higher strength of the acrylic material is effectively utilized, separation of a soil body and the model pile in a shearing process can be avoided, and the measurement accuracy of the contact interface shearing force of the soil body and a structural object is improved.
According to the invention, the design of the flange plate and the cover plate is adopted, the adjustment of the height-diameter ratio of the soil sample can be realized by selecting the fixed component and the bag body which are in the specification corresponding to the height-diameter ratio of the soil sample, and the adjustment can be carried out by matching the mode of placing the cushion block at the bottom of the bag body, so that the requirements of different sample sizes can be met under the condition of not replacing the tank body of the shearing tank, the method has remarkable advantages in large sample test, and the actual working condition can be better simulated in the geotechnical test.
The invention adopts a servo control system to control the electric cylinder, and has a plurality of loading modes, such as: stress control, displacement control, monotonic load control, cyclic load control and the like, thereby providing favorable conditions for loading control in different modes and meeting test requirements of multiple modes, high stress, complex stress and the like.
The shearing tank body is made of steel or stainless steel, and can be designed according to the stress requirement, so that convenience is brought to simulation of high stress and complex stress.
When the pile-soil interface shear test is carried out, the two ends of the model pile penetrate through the soil sample, so that the shear displacement of the structure is greatly improved, and the research on the problem of large contact deformation of pile soil can be satisfied. Meanwhile, by utilizing the shearing device, not only can the pile-soil interface shearing test be performed, but also static pressure pile test, soil pressure box calibration test, coarse-grained soil and pile interface shearing test and the like can be performed, so that the functions are diversified.
In summary, the invention adopts the control system to control the power mechanism, can regulate and control the shearing displacement between the structure and the soil sample, pressurizes and controls the soil sample by inflating (or filling liquid) in the shearing tank so as to control the normal stress of the contact surface of the soil body and the structure, and utilizes the data acquisition system and the data storage system to acquire and store data, thereby realizing multifunctional, multi-mode and automatic measurement, having high measurement precision, simple operation, better economic benefit and wide application prospect.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a schematic view of the structure of the fixing assembly of the present invention;
FIG. 3 is an enlarged schematic view of a portion of FIG. 1 at A;
FIG. 4 is an enlarged partial schematic view at B in FIG. 1;
fig. 5 is a schematic view of the installation of the spacer block of the present invention.
Reference numerals: 1. a supporting structure, a power mechanism and a driving mechanism; 3. the device comprises a tank body, 31, an upper mounting port, 32, a lower mounting port, 33, a pressurizing port, 34, a pressure relief port, 35, a wire outlet hole, 36, a pressure gauge, 4, a bag body, 5, a soil sample, 6 and a model pile; 7. the device comprises a fixing component, 71, a flange plate, 72, a clamping step, 73, a hoop, 74, a base plate, 75, a backing ring, 76, a cover plate, 8, a cushion block, 9, a tension and compression sensor, 91, a first floating joint, 92, a second floating joint, 93, a fish-eye joint bearing, 10, a first high-precision displacement meter, 11, a second high-precision displacement meter, 12, a third high-precision displacement meter, 13, an upper hoop rod, 14, an upper supporting rod, 15, a lower hoop rod, 16, a lower supporting rod, 17, an inner supporting rod, 18, a linear bearing, 19, a control system, 20, a data acquisition system, 21 and a data storage system.
Detailed Description
In order to make the technical objects, technical solutions and advantageous effects of the present invention more clear, the technical solutions of the present invention are further described below with reference to fig. 1 to 5 and specific embodiments.
An embodiment of a large-scale multifunctional soil and structure interface shearing device:
the utility model provides a large-scale multi-functional soil and structure thing interface shearing mechanism includes bearing structure 1, power unit 2, control system 19 and data acquisition system 20, power unit 2 installs on bearing structure 1, control system 19 controls the operation of power unit 2, still include the shearing jar, the shearing jar includes a jar body 3, be provided with on the jar body 3 and go up mounting hole 31, lower mounting hole 32, pressure port 33, pressure release mouth 34 and wire hole 35, the valve is installed respectively in pressure port 33, pressure release mouth 34, install balloon 4 in the jar body 3, balloon 4 is cylindrical structure, balloon 4's material is silica gel or rubber, balloon 4's size can be according to the soil sample 5 size that needs of test change, balloon 4's both ends extend to upper mounting hole 31 and lower mounting hole 32 department respectively, balloon 4's diameter is less than the diameter of upper mounting hole 31 or lower mounting hole 32, it has gas or liquid to fill between balloon 4 and jar body 3 inner wall, still install the manometer 36 that is used for monitoring pressure in jar body 3, manometer 36 selects high manometer 36 to take measurements to the precision, can measure barometer 36 and can measure the barometric pressure, and can store the barometric pressure; the bag body 4 is filled with the soil sample 5, the model pile 6 is placed in the soil sample 5, the axial direction of the model pile 6 is consistent with the axial direction of the bag body 4, the model pile 6 is a structure, and two ends of the model pile 6 penetrate through the soil sample 5, so that normal force born by a contact interface of soil and the structure is always perpendicular to a contact surface of the soil and the structure, the area of the contact surface is not changed along with the increase of shearing displacement in the shearing process, the shearing displacement of the structure is greatly improved, and the research of the problem of large deformation of pile-soil contact can be met;
The upper mounting opening 31 and the lower mounting opening 32 of the tank body 3 are respectively provided with a detachable fixing component 7, and the fixing component 7 is arranged on the tank body 3 and forms a sealing structure in the tank body 3.
As shown in fig. 2 and fig. 3, the fixing assembly 7 includes a flange 71, a backing plate 74, a backing ring 75 and a cover plate 76, where the flange 71, the backing plate 74, the backing ring 75 and the cover plate 76 are all in an annular structure, the flange 71 is detachably fixed at the upper mounting opening 31 and/or the lower mounting opening 32 of the tank body 3 by bolts, a clamping step 72 is fixed at the top of one side of the flange 71, which is located at the inner ring, in the circumferential direction, a hoop 73 is installed at the outer ring of the clamping step 72, the top of the capsule body 4 is fixed between the clamping step 72 and the hoop 73 after passing through the clamping step 72, the capsule body 4 and the hoop 73 are connected by using high-strength adhesive, and the diameter of the inner ring of the flange 71 is matched with that of the capsule body 4;
backing plate 74 and backing ring 75 all are placed on soil sample 5 surface and all are located the bag body 4 inboard, the backing ring 75 can adopt the ya keli material, the backing ring 75 is arranged in the backing plate 74 inner circle, backing ring 75 inner circle and the external circumference direct contact of model stake 6, the backing ring 75 can be adopted to strain the mode of deciding in the experiment and dispel (can adopt the mode that changes soil sample height and strain deciding backing ring 75 and have an influence to the shearing force in this device, and change the material of backing ring 75 can produce the influence etc. to the shearing force and strain decides, belong to the debugging process of test equipment), the apron 76 covers on backing plate 74 and backing ring 75 surface and can dismantle fixed connection through the bolt with the ring flange 71, be provided with sealant and rubber pad between apron 76 and the ring flange 71, be equipped with the clearance between apron 76 inner circle and the external circumference of model stake 6, avoid apron 76 to exert an influence to the shearing force to the external circumference diameter of apron 76 is greater than the diameter of backing plate 74.
The fixed subassembly 7 can fix the bag body 4, effectively improves the steadiness of bag body 4, avoids bag body 4 to drop at pressurization and shearing in-process, and the setting of backing plate 74 makes soil sample 5 be in the pressure action scope of shearing jar completely to the influence of the boundary effect at soil sample 5 both ends to its stress level has effectively been reduced. In this embodiment, the fixing member 7 is made of steel or stainless steel.
The setting of the backing ring 75 can adapt to the model piles 6 with different diameters, when the model piles 6 with different diameters are replaced, the backing ring 75 with corresponding size can be replaced firstly, and the utilization rate of the backing plate 74 can be effectively improved; in addition, the pad 74 may be provided with water permeable stones and pressure control means depending on the test requirements;
further, as one embodiment of the present invention, as shown in fig. 5, a spacer 8 with adjustable height is disposed between the bottom of the inner side of the bag body 4 and the fixing component 7, so as to further facilitate adjustment of the height-diameter ratio of the soil sample 5.
By changing the fixing components 7 and the bag body 4 with different sizes, the height-diameter ratio of the soil sample 5 can be adjusted, and the device can test the soil sample 5 with different sizes without changing a new tank body 3.
The top end and the bottom end of the model pile 6 respectively extend out of the cover plate 76 of the corresponding fixing assembly 7, the output rod of the power mechanism 2 and the model pile 6 are coaxially arranged, and a tension and compression sensor 9 is hinged between the end part of the output rod of the power mechanism 2 and the top end of the model pile 6; the two ends of the tension and compression sensor 9 are respectively connected with the top end of the model pile 6 through the end parts of the output rod of the power mechanism 2 through a hinge structure, so that the force measured by the tension and compression sensor 9 in the shearing test process is not influenced by bending moment (or eccentric force), and the influence on the measurement of the shearing force when the axis of the model pile 6 is not completely coincident with the axis of the output rod (namely the telescopic rod of the electric cylinder) of the power mechanism 2 is effectively avoided.
Specifically, as shown in fig. 4, the pull-press sensor 9 is hinged in the following manner: a first floating joint 91 is connected between one end of the pull-press sensor 9 and the top end of the model pile 6, the other end of the pull-press sensor 9 is connected with a second floating joint 92, the second floating joint 92 is connected with the end part of an output rod of the power mechanism 2 through a fisheye joint bearing 93, the inner ring of the fisheye joint bearing 93 is fixedly connected with the end part of the output rod of the power mechanism 2 through a transfer shaft, and the outer ring of the fisheye joint bearing 93 is fixedly connected with the second floating joint 92.
The floating joint and the fish-eye joint bearing 93 are both of conventional structures, and detailed descriptions thereof are omitted.
The first high-precision displacement meter 10 for measuring the axial displacement of the model pile 6 is arranged at the position, extending out of the fixed assembly 7, of the top end of the model pile 6, the second high-precision displacement meter 11 for measuring the axial displacement of the model pile 6 is arranged at the position, extending out of the fixed assembly 7, of the bottom end of the model pile 6, the third high-precision displacement meter 12 for measuring the radial displacement of the soil sample 5 is arranged in the tank body 3, the tension and compression sensor 9, the first high-precision displacement meter 10, the second high-precision displacement meter 11 and the third high-precision displacement meter 12 are respectively connected with the data acquisition system 20 through wires, and the data acquisition system 20 is connected with the data storage system 21 through wires. The data acquisition system 20 has an automatic acquisition function, can effectively extract dynamic data in the whole shearing process, and the data storage system 21 is a computer host and a computer display.
The lead wire of the third high-precision displacement meter 12 is connected out from the wire outlet hole 35 of the tank body 3, and the wire outlet hole 35 is sealed by high-strength sealant after the lead wire is connected out.
The axes of the measuring rods of the first high-precision displacement meter 10 and the second high-precision displacement meter 11 are parallel to the axis of the model pile 6, and the axis of the measuring rod of the third high-precision displacement meter 12 is perpendicular to the axis of the model pile 6;
the periphery of the part, extending out of the fixing assembly 7, of the top end of the model pile 6 is fixedly connected with an upper hoop rod 13 which is horizontally arranged, the first high-precision displacement meter 10 is supported by an upper supporting rod 14, the upper supporting rod 14 is fixed on a steel frame, and a measuring rod of the first high-precision displacement meter 10 is contacted with the upper hoop rod 13; the periphery of the part, extending out of the fixed assembly 7, of the bottom end of the model pile 6 is fixedly connected with a lower hoop rod 15 which is horizontally arranged, the second high-precision displacement meter 11 is supported by a lower supporting rod 16, the lower supporting rod 16 is fixed on the ground, and a measuring rod of the second high-precision displacement meter 11 is contacted with the lower hoop rod 15; in a specific application, the upper support rod 14 and the lower support rod 16 can be magnetic gauge stands, the magnetic gauge stands are fixed on a steel frame, and the first high-precision displacement meter 10 or the second high-precision displacement meter 11 is arranged on the magnetic gauge stands;
an inner supporting rod 17 is vertically fixed in the tank body 3, a plurality of third high-precision displacement meters 12 are installed on the inner supporting rod 17 from top to bottom, and two first high-precision displacement meters 10 and two second high-precision displacement meters 11 are symmetrically arranged respectively, so that measurement is more accurate.
The first high-precision displacement meter 10, the second high-precision displacement meter 11, and the third high-precision displacement meter 12 may employ vibrating wire type or laser displacement sensors, or the like.
Further, as one embodiment of the present invention, as shown in fig. 1, an adapter plate is mounted on the cover plate 76 in the fixing assembly 7 at the lower mounting opening 32, a linear bearing 18 is mounted on the adapter plate, the linear bearing 18 is slidably connected with the model pile 6, and the linear bearing 18 can force the axis of the model pile 6 to coincide with the axis of the soil sample 5 so as to meet the requirement of the shearing test on the perpendicularity of the model pile 6, so that more accurate test data can be obtained.
Further, as one embodiment of the present invention, the support structure 1 is a steel frame, the steel frame is a door-shaped structure, the power mechanism 2 is an electric cylinder, the electric cylinder is vertically installed on the steel frame, the control system 19 is a servo control system 19, the servo control system 19 is connected with the electric cylinder, and the servo control system 19 has multiple loading modes, such as: stress control, displacement control, monotonic load control, cyclic load control, etc., thereby providing advantages for loading control in different modes.
The servo control system 19 controls the power mechanism 2 to regulate and control the shearing displacement between the model pile 6 and the soil sample 5.
The servo control system 19, the electric cylinder, the tension and compression sensor 9, the data acquisition system 20, the data storage system 21 and the high-precision displacement meter are all conventional devices, and the specific structure is not described again.
The large-scale multifunctional soil and structure interface shearing device can be used for not only carrying out pile-soil interface shearing tests, but also carrying out static pressure pile tests, soil pressure box calibration tests, coarse-grained soil and pile interface shearing tests and the like.
The pile-soil interface shear test process is as follows:
step S1: the third high-precision displacement meter 12 is arranged in the tank body 3, a wire of the third high-precision displacement meter 12 is connected out from a wire outlet hole 35 of the tank body 3, the wire outlet hole 35 is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component 7 and a bag body 4 with the specification corresponding to the height-diameter ratio of the soil sample 5 are selected, the fixed component 7 is arranged at a mounting opening 32 under the tank body 3, at the moment, the height-diameter ratio of the soil sample 5 can be further adjusted according to the placement of cushion blocks 8 with different sizes, a flange plate 71 and a hoop 73 in the fixed component 7 are arranged at the mounting opening 31 on the tank body 3, and two ends of the bag body 4 are respectively fixed at the corresponding flange plate 71 through the hoop 73;
step S2: installing the model pile 6, enabling two ends of the model pile 6 to penetrate through the fixing assemblies 7 at two ends, and enabling the axial direction of the model pile 6 to be consistent with the tensile direction provided by the power mechanism 2;
Before the soil sample 5 is prepared, the perpendicularity of the model pile 6 needs to be ensured, and the axial direction of the model pile 6 is prevented from being consistent with the tensile direction provided by the power mechanism 2.
Step S3: according to the test requirement, filling soil into the bag body 4 to obtain a circular soil sample 5, wherein the soil filling mode can adopt a rain falling method, after the soil filling is finished, installing a backing ring 75, a backing plate 74 and a cover plate 76 in a fixing assembly 7 at a mounting opening 31 on the tank body 3, and during the installation, placing the backing plate 74 and the backing ring 75 on the surface of the soil sample 5, wherein the inner ring of the backing ring 75 is directly contacted with the periphery of a model pile 6, the cover plate 76 covers the surfaces of the backing plate 74 and the backing ring 75 and is connected with a flange plate 71, and a gap is arranged between the inner ring of the cover plate 76 and the periphery of the model pile 6 to finish the packaging;
the device is convenient to adopt a rain falling method for preparing samples, can effectively reduce the preparation difficulty of the soil samples 5, obviously improve the preparation efficiency and the relative density control precision of the soil body and the soil samples 5, and is a conventional sample preparation method for the geotechnical profession, and the concrete sample preparation method is not repeated.
Step S4: the power mechanism 2, the tension and compression sensor 9, the first high-precision displacement meter 10 and the second high-precision displacement meter 11 are sequentially installed, the power mechanism 2 is connected with the control system 19, the tension and compression sensor 9, the first high-precision displacement meter 10, the second high-precision displacement meter 11 and the third high-precision displacement meter 12 are respectively connected with the data acquisition system 20 through wires, and the data acquisition system 20 is connected with the data storage system 21;
Step S5: closing a valve at the pressure release opening 34, applying air pressure or hydraulic confining pressure to the soil sample 5 in the tank body 3 through the pressure opening 33, obtaining the confining pressure of the soil sample 5 according to the measured value of the pressure gauge 36 arranged on the tank body 3, and then applying load to the model pile 6 through the power mechanism 2 to control the axial displacement of the model pile 6, so as to realize the pile-soil interface shearing simulation;
step S6: the displacement of the model pile 6 and the body strain of the soil sample 5 in the interface shearing process of the soil sample 5 and the model pile 6 can be obtained through the first high-precision displacement meter 10, the second high-precision displacement meter 11 and the third high-precision displacement meter 12; the shearing force in the shearing process can be obtained through the pulling and pressing sensor 9;
step S7: and when the displacement of the model pile 6 reaches a preset value, loading of the power mechanism 2 can be stopped, and after the test is finished, a valve at the pressure relief opening 34 is opened for pressure relief.
In this embodiment, according to the requirements of the test scheme, the loading of the power mechanism 2 can be stopped when the displacement of the model pile 6 reaches a predetermined value. In other embodiments, the power mechanism 2 can also apply a cyclic load, so that the cyclic load test requirement can be met.
According to the steps, the coarse-grained soil and pile contact interface shearing test can be completed, because coarse-grained soil particles are larger, the requirements on the size of test equipment are higher, namely, larger storage space of soil samples 5, larger power devices and larger shearing displacement are needed, the bag body 4 of the device can be subjected to height-to-diameter ratio conversion according to the needs, the load of an electric cylinder can be replaced according to the needs, and the shearing displacement can be regulated and controlled by regulating the stroke of the electric cylinder and the pile top distance between an electric cylinder telescopic rod and a model pile 6, so that the problems can be effectively solved.
The static pile test process is as follows:
step S1: the third high-precision displacement meter 12 is arranged in the tank body 3, a wire of the third high-precision displacement meter 12 is connected out from a wire outlet hole 35 of the tank body 3, the wire outlet hole 35 is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component 7 and a bag body 4 with the specifications corresponding to the height-diameter ratio of the soil sample 5 are selected, the fixed component 7 is arranged at a lower mounting opening 32 of the tank body 3, a backing ring 75 and a backing plate 74 in the fixed component 7 at the lower mounting opening 32 are replaced by a disc-shaped whole backing plate 74 so as to block the bottom of the soil sample 5, at the moment, the height-diameter ratio of the soil sample 5 can be further adjusted according to the cushion blocks 8 placed in different sizes, a flange 71 and a hoop 73 in the fixed component 7 are arranged at the upper mounting opening 31 of the tank body 3, and two ends of the bag body 4 are respectively fixed at the corresponding flange 71 through the hoops 73;
step S2: according to the test requirement, filling soil into the bag body 4 to obtain a cylindrical soil sample 5, after filling the soil, installing a backing ring 75, a backing plate 74 and a cover plate 76 in a fixing assembly 7 at a mounting opening 31 on the tank body 3 by adopting a rain falling method, wherein during installation, the backing plate 74 and the backing ring 75 are both placed on the surface of the soil sample 5, and the cover plate 76 covers the surfaces of the backing plate 74 and the backing ring 75 and is connected with the flange 71, so that a space for allowing a model pile 6 to penetrate into the soil sample 5 is reserved in the centers of the backing plate 74, the backing ring 75 and the cover plate 76 in the fixing assembly at the mounting opening 31 on the tank body 3;
Step S3: closing the valve at the pressure relief port 34 and performing zero setting on the pressure gauge 36;
step S4: the power mechanism 2, the tension and compression sensor 9 and the model pile 6 are sequentially installed, the model pile 6 is installed on the upper portion of the soil sample 5, the axial direction of the model pile 6 is consistent with the tensile direction provided by the power mechanism 2, the power mechanism 2 is connected with the control system 19, the tension and compression sensor 9 and the end resistances in the model pile 6 are respectively connected with the data acquisition system 20 through wires, and the data acquisition system 20 is connected with the data storage system 21;
step S5: applying air pressure or hydraulic confining pressure to the soil sample 5 in the tank body 3 through the pressurizing opening 33, obtaining the confining pressure of the soil sample 5 according to the measured value of the pressure gauge 36 arranged on the tank body 3, and then applying load to the model pile 6 through the power mechanism 2 to control the model pile 6 to penetrate into the soil sample 5 at a certain speed so as to realize simulation of the static pile;
step S6: in the static pile test process, pile top pressure is measured by adopting a pulling and pressing sensor 9, and end resistance in the pile pressing process is measured by adopting an end resistance meter in the model pile 6; simulating the proportion of end resistance and pile side friction force in the pile sinking process of the static pressure pile when different soil depths are achieved by changing the soil sample confining pressure; calculating pile body penetration depth before pile pressing, namely simulating static pressure pile penetration depth when the difference between the soil sample height and the pile diameter 8-10 times of the model pile is 8-10 times of the pile diameter of the soil sample bottom of the model pile 6, and ending static pressure pile penetration;
Step S7: after the test is completed, the valve at the pressure relief port 34 is opened for pressure relief.
The soil pressure box calibration test process is as follows:
step S1: the third high-precision displacement meter 12 is arranged in the tank body 3, a wire of the third high-precision displacement meter 12 is connected out from a wire outlet hole 35 of the tank body 3, the wire outlet hole 35 is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component 7 and a bag body 4 with the specification corresponding to the height-diameter ratio of the soil sample 5 are selected, the fixed component 7 is arranged at a mounting opening 32 under the tank body 3, at the moment, the height-diameter ratio of the soil sample 5 can be further adjusted according to the placement of cushion blocks 8 with different sizes, a flange plate 71 and a hoop 73 in the fixed component 7 are arranged at the mounting opening 31 on the tank body 3, and two ends of the bag body 4 are respectively fixed at the corresponding flange plate 71 through the hoop 73;
step S2: embedding a miniature soil pressure box on the model pile 6, and then installing the model pile 6 in a shearing tank, so that two ends of the model pile 6 penetrate through the fixing assemblies 7 at two ends, and the axial direction of the model pile 6 is consistent with that of the capsule body 4;
step S3: according to the test requirement, filling soil into the bag body 4 to obtain a circular soil sample 5, wherein a rain fall method can be adopted for the soil filling mode, after the soil filling is finished, a backing plate 75, a backing plate 74 and a cover plate 76 in a fixing assembly 7 are arranged at a mounting opening 31 on the tank body 3, during the mounting, the backing plate 74 and the backing plate 75 are both placed on the surface of the soil sample 5, the inner ring of the backing plate 75 is directly contacted with the periphery of the model pile 6, and the cover plate 76 covers the surfaces of the backing plate 74 and the backing plate 75 and is connected with the flange plate 71 to finish the packaging;
Step S4: after the soil sample 5 and the model pile 6 are packaged, closing a valve at the pressure relief opening 34, applying air pressure or hydraulic confining pressure to the soil sample 5 in the tank body 3 through the pressure opening 33, comparing the reading of the pressure gauge 36 with the pressure measured by the soil pressure box, and finally correcting the sensitivity coefficient of the soil pressure box according to the reading of the pressure gauge 36 so as to enable the data measured by the soil pressure box to be consistent with the reading of the pressure gauge 36, thereby completing the calibration test of the soil pressure box;
the method is one of the combined calibration methods of the soil pressure box, when the liquid confining pressure is applied to the interior of the shearing tank, the soil pressure box calibration mode combining the liquid mark and the sand mark is adopted, and when the air pressure is the air pressure, the soil pressure box calibration mode combining the air mark and the sand mark is adopted;
the method effectively utilizes the uniformity of the pressure applied by the annular soil sample 5 to the surface of the pile body, can calibrate a plurality of soil pressure boxes at the same time, and can effectively improve the calibration efficiency of the soil pressure boxes.
Step S5: after the test is completed, the valve at the pressure relief port 34 is opened for pressure relief.
The above embodiments are not limited in any way by the shape, materials, structure, etc. of the present invention, and any simple modification, equivalent variation and modification made to the above embodiments according to the technical substance of the present invention are all included in the protection scope of the technical solution of the present invention.
Claims (10)
1. The utility model provides a large-scale multi-functional soil and structure thing interface shearing mechanism, includes bearing structure, power unit, control system and data acquisition system, and power unit installs on bearing structure, its characterized in that: the device comprises a tank body, and is characterized by further comprising a shearing tank, wherein the tank body is provided with an upper mounting opening, a lower mounting opening, a pressurizing opening, a pressure relief opening and a wire outlet, a bag body is arranged in the tank body, the bag body is of a cylindrical structure, two ends of the bag body extend to the upper mounting opening and the lower mounting opening respectively, the diameter of the bag body is smaller than that of the upper mounting opening or the lower mounting opening, gas or liquid is filled between the bag body and the inner wall of the tank body, a soil sample is filled in the bag body, a model pile is placed in the soil sample, the axial direction of the model pile is consistent with that of the bag body, and two ends of the model pile penetrate through the soil sample;
the upper mounting opening and the lower mounting opening of the tank body are respectively provided with a detachable fixing component, the fixing components are arranged on the tank body, a sealing structure is formed in the tank body, two ends of the bag body are respectively fixed at the fixing components, one side surface of the fixing components facing the inside of the tank body is flush with the inner surface of the tank body, and two ends of a soil sample are respectively contacted with one side surface of the fixing components facing the inside of the tank body;
The top end and the bottom end of the model pile extend out of the corresponding fixing assemblies respectively, an output rod of the power mechanism and the model pile are coaxially arranged, and a tension and compression sensor is hinged between the end part of the output rod of the power mechanism and the top end of the model pile;
the part of the top end of the model pile, which extends out of the fixing component, is provided with a first high-precision displacement meter used for measuring the axial displacement of the model pile, the part of the bottom end of the model pile, which extends out of the fixing component, is provided with a second high-precision displacement meter used for measuring the axial displacement of the model pile, the tank body is internally provided with a third high-precision displacement meter used for measuring the radial displacement of the soil sample, and the tension and compression sensor, the first high-precision displacement meter, the second high-precision displacement meter and the third high-precision displacement meter are respectively connected with a data acquisition system through wires.
2. The large-scale multi-functional soil and structure interface shearing device as claimed in claim 1, wherein: the supporting structure is a steel frame, the steel frame is a door-shaped structure, the power mechanism is an electric cylinder, the electric cylinder is vertically arranged on the steel frame, the control system is a servo control system, and the servo control system is connected with the electric cylinder.
3. The large-scale multi-functional soil and structure interface shearing device as claimed in claim 1, wherein: the fixing assembly comprises a flange, a base plate, a backing ring and a cover plate, wherein the flange, the base plate, the backing ring and the cover plate are of annular structures, the flange is detachably fixed at an upper mounting opening and/or a lower mounting opening of the tank body through bolts, a clamping step is fixed at the top of one side of the flange, which is positioned on the inner ring, along the circumferential direction, a hoop is arranged on the outer ring of the clamping step, the top end of the bag body is fixed between the clamping step and the hoop after passing through the clamping step, and the diameter of the inner ring of the flange is matched with that of the bag body;
Backing plate and backing ring all are placed on the soil sample surface and all are located the bag body inboard, and the backing ring is placed in the backing plate inner circle, backing ring inner circle and the outer week direct contact of model stake, the apron covers on backing plate and backing ring surface and can dismantle fixed connection with the ring flange through the bolt, is equipped with the clearance between the outer week of apron inner circle and model stake, and the periphery diameter of apron is greater than the diameter of backing plate.
4. The large-scale multi-functional soil and structure interface shearing device as claimed in claim 1, wherein: the axes of the measuring rods of the first high-precision displacement meter and the second high-precision displacement meter are parallel to the axis of the model pile, and the axis of the measuring rod of the third high-precision displacement meter is perpendicular to the axis of the model pile;
the periphery of the part of the top end of the model pile, which extends out of the fixing component, is fixedly connected with an upper hoop rod which is horizontally arranged, the first high-precision displacement meter is supported by an upper supporting rod, the upper supporting rod is fixed on a supporting structure, and a measuring rod of the first high-precision displacement meter is contacted with the upper hoop rod; the periphery of the part of the bottom end of the model pile, which extends out of the fixing component, is fixedly connected with a lower hoop rod which is horizontally arranged, the second high-precision displacement meter is supported by a lower supporting rod, the lower supporting rod is fixed on the ground, and a measuring rod of the second high-precision displacement meter is contacted with the lower hoop rod;
An inner supporting rod is vertically fixed in the tank body, a plurality of third high-precision displacement meters are installed on the inner supporting rod from top to bottom, and two first high-precision displacement meters and two second high-precision displacement meters are symmetrically arranged respectively.
5. The large-scale multi-functional soil and structure interface shearing device as claimed in claim 1, wherein: a first floating joint is connected between one end of the tension-compression sensor and the top end of the model pile, the other end of the tension-compression sensor is connected with a second floating joint, and the second floating joint is connected with the end part of an output rod of the power mechanism through a fish-eye joint bearing.
6. A large scale multi-functional soil and structure interface shearing apparatus as defined in claim 3, wherein: and the cover plate in the fixed assembly at the lower mounting opening is provided with an adapter plate, and the adapter plate is provided with a linear bearing which is in sliding connection with the model pile.
7. The large-scale multi-functional soil and structure interface shearing device as claimed in claim 1, wherein: a cushion block with adjustable height is arranged between the bottom of the inner side of the bag body and the fixed component.
8. The method for using the large-scale multifunctional soil and structure interface shearing apparatus as claimed in any one of claims 3 to 7, wherein: the method comprises the following steps:
Step S1: a third high-precision displacement meter is arranged in the tank body, a lead of the third high-precision displacement meter is connected out from a wire outlet hole of the tank body, the wire outlet hole is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component and a bag body with the specification corresponding to the height-diameter ratio of a soil sample are selected, the fixed component is arranged at a lower mounting opening of the tank body, a flange plate and a hoop ring in the fixed component are arranged at the mounting opening of the tank body, and two ends of the bag body are respectively fixed at the corresponding flange plate through the hoop ring;
step S2: installing a model pile, enabling two ends of the model pile to penetrate through the fixing assemblies at the two ends, and enabling the axial direction of the model pile to be consistent with the tensile direction provided by the power mechanism;
step S3: according to the test requirement, filling soil into the bag body to obtain a circular soil sample, after filling the soil, installing a backing plate, a backing plate and a cover plate in a fixing assembly at a mounting opening on the tank body, wherein during installation, the backing plate and the backing plate are both placed on the surface of the soil sample, an inner ring of the backing plate is in direct contact with the periphery of a model pile, the cover plate covers the surfaces of the backing plate and is connected with a flange plate, and a gap is arranged between the inner ring of the cover plate and the periphery of the model pile to finish packaging;
step S4: the power mechanism, the tension and compression sensor, the first high-precision displacement meter and the second high-precision displacement meter are sequentially installed, the power mechanism is connected with the control system, the tension and compression sensor, the first high-precision displacement meter, the second high-precision displacement meter and the third high-precision displacement meter are respectively connected with the data acquisition system through wires, and the data acquisition system is connected with the data storage system;
Step S5: closing a valve at the pressure release opening, applying air pressure or hydraulic confining pressure to the soil sample in the tank body through the pressure opening, obtaining the soil sample confining pressure according to the measured value of the pressure gauge additionally arranged on the tank body, and then applying load to the model pile through the power mechanism to control the axial displacement of the model pile so as to realize the pile-soil interface shearing simulation;
step S6: the displacement of the model pile and the body strain of the soil sample in the process of shearing the interface between the soil sample and the model pile can be obtained through the first high-precision displacement meter, the second high-precision displacement meter and the third high-precision displacement meter; the shearing force in the shearing process can be obtained through the pulling and pressing sensor;
step S7: and when the displacement of the model pile reaches a preset value, loading of the power mechanism can be stopped, and after the test is finished, a valve at the pressure relief opening is opened for pressure relief.
9. The method for using the large-scale multifunctional soil and structure interface shearing apparatus as claimed in any one of claims 3 to 7, wherein: the method comprises the following steps:
step S1: a third high-precision displacement meter is arranged in the tank body, a lead of the third high-precision displacement meter is connected out from a lead hole of the tank body, the lead hole is sealed by high-strength sealant after the lead hole is connected out, a fixed component and a bag body with the specifications corresponding to the height-diameter ratio of a soil sample are selected, the fixed component is arranged at a lower mounting opening of the tank body, a backing ring and a backing plate in the fixed component at the lower mounting opening are replaced by a disc-shaped whole backing plate so as to block the bottom of the soil sample, a flange plate and a hoop in the fixed component are arranged at the mounting opening of the tank body, and two ends of the bag body are respectively fixed at the corresponding flange plate through the hoops;
Step S2: according to the test requirement, filling soil into the bag body to obtain a cylindrical soil sample, and after filling the soil, installing a backing ring, a backing plate and a cover plate in the fixing assembly at an installation opening on the tank body, wherein the backing plate and the backing ring are both placed on the surface of the soil sample when the soil is installed, and the cover plate covers the surfaces of the backing plate and the backing ring and is connected with the flange plate;
step S3: closing a valve at the pressure relief opening and performing zero setting on the pressure gauge;
step S4: the method comprises the steps that a power mechanism, a pulling and pressing sensor and a model pile are sequentially installed, the model pile is installed on the upper portion of a soil sample, the axial direction of the model pile is consistent with the pulling direction provided by the power mechanism, the power mechanism is connected with a control system, the pulling and pressing sensor and end resistors in the model pile are respectively connected with a data acquisition system through wires, and the data acquisition system is connected with a data storage system;
step S5: applying air pressure or hydraulic confining pressure to the soil sample in the tank body through the pressurizing opening, obtaining the soil sample confining pressure according to the measured value of the pressure gauge arranged on the tank body, and then applying load to the model pile through the power mechanism to control the model pile to penetrate into the soil sample at a certain speed so as to realize simulation of the static pressure pile;
step S6: in the static pile test process, pile top pressure is measured by adopting a tension and compression sensor, and end resistance in the pile pressing process is measured by adopting an end resistance meter in the model pile; simulating the proportion of end resistance and pile side friction force in the pile sinking process of the static pressure pile when different soil depths are achieved by changing the soil sample confining pressure; calculating pile body penetration depth before pile pressing, namely simulating static pile penetration depth when the difference between the soil sample height and the pile diameter 8-10 times of the model pile is 8-10 times of the pile diameter of the soil sample bottom of the model pile, and ending static pile penetration when the pile tip of the model pile is 8-10 times of the pile diameter;
Step S7: and after the test is finished, opening a valve at the pressure relief opening to relieve pressure.
10. The method for using the large-scale multifunctional soil and structure interface shearing apparatus as claimed in any one of claims 3 to 7, wherein: the method comprises the following steps:
step S1: a third high-precision displacement meter is arranged in the tank body, a lead of the third high-precision displacement meter is connected out from a wire outlet hole of the tank body, the wire outlet hole is sealed by high-strength sealant after the wire outlet hole is connected out, a fixed component and a bag body with the specification corresponding to the height-diameter ratio of a soil sample are selected, the fixed component is arranged at a lower mounting opening of the tank body, a flange plate and a hoop ring in the fixed component are arranged at the mounting opening of the tank body, and two ends of the bag body are respectively fixed at the corresponding flange plate through the hoop ring;
step S2: embedding a miniature soil pressure box on the model pile, and then installing the model pile in a shearing tank, so that two ends of the model pile penetrate through fixing assemblies at two ends, and the axial direction of the model pile is consistent with the axial direction of the capsule body;
step S3: according to the test requirement, filling soil into the bag body to obtain a circular soil sample, after filling the soil, installing a backing plate, a backing plate and a cover plate in a fixing assembly at an installation opening on the tank body, wherein the backing plate and the backing plate are both placed on the surface of the soil sample during installation, the inner ring of the backing plate is in direct contact with the periphery of a model pile, and the cover plate covers the surfaces of the backing plate and is connected with a flange plate to finish packaging;
Step S4: after the soil sample and the model pile are packaged, closing a valve at a pressure release opening, applying air pressure or hydraulic confining pressure to the soil sample in the tank body through a pressurizing opening, comparing the reading of the pressure gauge with the pressure measured by the soil pressure box, and finally correcting the sensitivity coefficient of the soil pressure box according to the reading of the pressure gauge so as to enable the data measured by the soil pressure box to be consistent with the reading of the pressure gauge, thereby completing a calibration test of the soil pressure box;
step S5: and after the test is finished, opening a valve at the pressure relief opening to relieve pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111483759.6A CN114136811B (en) | 2021-12-07 | 2021-12-07 | Large-scale multifunctional soil and structure interface shearing device and application method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111483759.6A CN114136811B (en) | 2021-12-07 | 2021-12-07 | Large-scale multifunctional soil and structure interface shearing device and application method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114136811A CN114136811A (en) | 2022-03-04 |
| CN114136811B true CN114136811B (en) | 2024-03-19 |
Family
ID=80384376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111483759.6A Active CN114136811B (en) | 2021-12-07 | 2021-12-07 | Large-scale multifunctional soil and structure interface shearing device and application method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114136811B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103076230A (en) * | 2013-02-05 | 2013-05-01 | 重庆交通大学 | Test method and test device of mechanical properties of soil-structure contact surface |
| CN108487333A (en) * | 2018-01-25 | 2018-09-04 | 中国地质大学（武汉） | A kind of pile pile and native plug contact surface circulation shear experimental rig and method |
| CN111896395A (en) * | 2020-08-12 | 2020-11-06 | 大连理工大学 | Soil and structure interface interaction parameter measuring device and testing method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109374440A (en) * | 2018-10-25 | 2019-02-22 | 浙江大学 | A kind of interface ring shear apparatus for being contemplated that the soil body and seeping erosion effect |
-
2021
- 2021-12-07 CN CN202111483759.6A patent/CN114136811B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103076230A (en) * | 2013-02-05 | 2013-05-01 | 重庆交通大学 | Test method and test device of mechanical properties of soil-structure contact surface |
| CN108487333A (en) * | 2018-01-25 | 2018-09-04 | 中国地质大学（武汉） | A kind of pile pile and native plug contact surface circulation shear experimental rig and method |
| CN111896395A (en) * | 2020-08-12 | 2020-11-06 | 大连理工大学 | Soil and structure interface interaction parameter measuring device and testing method |
Non-Patent Citations (1)
| Title |
|---|
| 王永洪 ; 刘俊伟 ; 张明义 ; 白晓宇 ; .大型土与结构相互作用恒刚度直剪试验装置研究.地下空间与工程学报.2019,(第06期),全文. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114136811A (en) | 2022-03-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111206627B (en) | Centrifugal model test device and method for influencing existing pile foundation by tunnel-foundation pit multiple excavation | |
| CN102478472B (en) | Test apparatus used for simulating influence of three-axis loading and unloading on engineering pile | |
| CN107449678A (en) | Large-scale triaxial shear test devices and methods therefor in situ | |
| CN106759547B (en) | Integral Abutment, pile foundation and soil interaction pseudo-static experimental measuring device and its installation method | |
| CN105223080B (en) | Evaluation method for jointed rock performance and bolting and grouting effects under compression-shear condition | |
| CN113089624B (en) | Adjacent foundation pit asynchronous excavation simulation test device and test method | |
| CN107675734B (en) | A kind of underwater directional vehicle construction dynamic monitoring method | |
| CN102808429B (en) | Pile foundation soaking load test method based on creep-strain separation | |
| CN103308394B (en) | Static lateral pressure coefficient determinator and method | |
| CN114136811B (en) | Large-scale multifunctional soil and structure interface shearing device and application method thereof | |
| CN212001309U (en) | Centrifugal model test device for influencing existing pile foundation by tunnel-foundation pit multiple excavation | |
| CN111579377B (en) | Dynamic and static triaxial test device capable of eliminating influence of membrane embedding effect | |
| CN107422097B (en) | Device for measuring soil consolidation performance and expansion force | |
| CN112942292A (en) | Small-volume calibration tank for seabed soil static sounding test | |
| CN110658064B (en) | Device and method for acquiring optimal supporting force of tunnel fluid lining support in simulation mode | |
| CN205506571U (en) | Ground water level dynamic change's foundation ditch model test device can simulate | |
| CN108844823B (en) | Device and method for measuring side friction resistance of soil layer at any depth | |
| CN207300760U (en) | A kind of large-scale triaxial shear test device in situ | |
| CN106400857A (en) | Model device and method used for field measuring of blockage degree of opening pile interior soil plug | |
| CN216194619U (en) | Test equipment for simulating unloading and uplifting of foundation pit excavation pit bottom soil body | |
| KR100397072B1 (en) | Large Cyclic Triaxial Testing Apparatus | |
| CN209368899U (en) | Three axis of pile-soil interface folds ring shear | |
| CN110017764B (en) | Method for measuring lateral deformation under different confining pressure conditions | |
| CN110044686B (en) | Portable triaxial stress-strain testing device loaded by counter-force | |
| CN211849649U (en) | Centrifugal model test device for measuring vertical and horizontal limit bearing capacity of pile foundation |
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 |