CN113049395A - Simulation device for composite stress mechanism of pile foundation of liquefied field and test method thereof - Google Patents
Simulation device for composite stress mechanism of pile foundation of liquefied field and test method thereof Download PDFInfo
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Abstract
A simulation device for a composite stress mechanism of a pile foundation of a liquefied field and a test method thereof belong to the technical field of geotechnical seismic engineering. The upper end of a vertical loading device is connected with an upper cross beam of a reaction frame in a sliding manner, the lower end of the vertical loading device is connected with the upper end face of a steel outer sleeve, a pile cap is fixed in the steel outer sleeve, a pile body is embedded into a laminated shearing model box, the bottom of the laminated shearing model box is fixed on a saturated soil body liquefaction excitation device, a horizontal circulating loading device is connected with a vertical beam corresponding to the reaction frame in a sliding manner, the horizontal circulating loading device is connected with the pile cap through the steel outer sleeve, and the model box loading device is connected with the vertical beam corresponding to the reaction frame in a sliding manner; when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box, and the vertical loading device, the horizontal circulating loading device, the model box loading device and the saturated soil liquefaction exciting device are respectively connected with the computer through data lines. The method is used for simulating the composite stress mechanism of the pile foundation of the liquefaction site.
Description
Technical Field
The invention belongs to the technical field of geotechnical seismic engineering, and particularly relates to a simulation device for a composite stress mechanism of a pile foundation of a liquefied field and a test method thereof.
Background
Pile foundations can appear in the selection of basic engineering schemes in some major projects, and the pile foundations have remarkable advantages in the aspects of reducing the settlement amount of the foundations, the seismic performance, the comprehensive construction cost and the like. However, in some engineering practices, various problems also occur in pile foundations, for example, in the fields of slope engineering, port and coast engineering, offshore engineering, high-speed railway engineering and the like, after liquefaction occurs in an inclined site according to past statistical data, the liquefied soil body pushes the pile foundation, and the pile is subjected to bending damage and buckling instability damage under the combined stress action of vertical load and the liquefied soil body on the pile. The types of loading devices for researching the pile-soil interaction are various, but the actual stress state of the pile-soil interaction cannot be simulated well, wherein the stacked shear model box is most widely applied. Therefore, the research of the test device capable of simulating the influence of the lateral flow of the liquefied soil body on the stress performance of the pile foundation is of great importance for the research of the pile damage mechanism.
Disclosure of Invention
The invention aims to provide a simulation device for a composite stress mechanism of a pile foundation in a liquefaction site, which aims to solve the problem that the existing test device cannot simulate the composite stress state of the pile foundation when a saturated soil body is liquefied and is subjected to lateral large deformation.
The second purpose of the invention is to provide a simulation test method for a composite stress mechanism of a pile foundation of a liquefied field, so as to solve the problem of exploring the damage mode and mechanism of the pile foundation under the complex stress condition.
The invention uses the eccentric vibration exciter in the saturated soil liquefaction exciting device at the bottom of the stacked shearing model box to vibrate under the control of a computer to liquefy the soil, and uses the horizontal vibration exciter connected at the pile cap to apply a circulating load to the pile foundation to simulate the circulating action of the earthquake on the pile.
In order to achieve the purpose, the invention adopts the technical scheme that:
the first scheme is as follows: the invention relates to a composite stress mechanism simulation device for a pile foundation of a liquefaction site, which comprises a reaction frame, a laminated shearing model box, a model box loading device, a horizontal circulating loading device, a vertical loading device, a saturated soil liquefaction exciting device and a steel outer sleeve, wherein the reaction frame is arranged on the upper surface of the model box;
the lower end of the reaction frame is fixed on a steel bottom plate, the vertical loading device is arranged in the reaction frame, the upper end of the vertical loading device is connected with an upper cross beam of the reaction frame in a sliding manner, the lower end of the vertical loading device is connected with the upper end face of a steel outer sleeve, the pile cap is fixed in the steel outer sleeve, a pile body is embedded into a laminated shearing model box, the bottom of the laminated shearing model box is fixed on a saturated soil body liquefaction exciting device, the saturated soil body liquefaction exciting device is fixed on the steel bottom plate, the horizontal circulating loading device is connected with a vertical beam corresponding to the reaction frame in a sliding manner, the horizontal circulating loading device is connected with the pile cap through the steel outer sleeve, and the model box loading device is connected with the vertical beam corresponding to the reaction frame in a sliding manner; when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box to drive the frame body corresponding to the laminated shearing model box to horizontally move; the vertical loading device, the horizontal circulating loading device, the model box loading device and the saturated soil liquefaction excitation device are respectively connected with the computer through data lines.
Scheme II: the invention relates to a composite stress mechanism simulation device for a pile foundation of a liquefaction site, which comprises a reaction frame, a laminated shearing model box, a model box loading device, a horizontal circulating loading device, weights, a saturated soil body liquefaction excitation device and a steel outer sleeve, wherein the reaction frame is arranged on the upper surface of the model box;
the lower end of the reaction frame is fixed on a steel bottom plate, the pile cap is fixed in a steel jacket, the pile body is embedded into a laminated shearing model box, the weight is arranged on the upper end surface of the pile cap, the bottom of the laminated shearing model box is fixed on a saturated soil liquefaction excitation device, the saturated soil liquefaction excitation device is fixed on the steel bottom plate, the horizontal circulation loading device is in sliding connection with a vertical beam corresponding to the reaction frame, the horizontal circulation loading device is connected with the pile cap through the steel jacket, and the model box loading device is in sliding connection with the vertical beam corresponding to the reaction frame; when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box to drive the frame body corresponding to the laminated shearing model box to horizontally move; the horizontal circulation loading device, the model box loading device and the saturated soil liquefaction excitation device are respectively connected with the computer through data lines.
The invention discloses a simulation test method for a composite stress mechanism of a pile foundation of a liquefied field, which comprises the following steps of:
the method comprises the following steps: sticking a resistance strain gauge along the axial direction of the pile body, and connecting the resistance strain gauge with a computer through a data line;
step two: placing a soil body prepared in advance in a laminated shearing model box, embedding a pile body and a vibrating wire type soil pressure box in the soil body, and connecting the vibrating wire type soil pressure box to a computer through a data line;
step three: inputting small-to-large vibration through an eccentric vibration exciter until soil in the laminated shearing model box is liquefied, and connecting a sensor on the eccentric vibration exciter to a computer through a data line;
step four: the computer controls a vertical loading hydraulic jack of the vertical loading device to apply a vertical load to the pile cap, controls the horizontal cyclic loading device to apply a horizontal load to the laminated shearing model box and pushes a soil body in the laminated shearing model box to generate shearing deformation;
step five: and the computer controls the horizontal cyclic loading device to apply horizontal cyclic load through a horizontal electromagnetic vibration exciter connected to the pile cap.
Compared with the prior art, the invention has the beneficial effects that:
(1) the horizontal cyclic loading device is arranged, so that horizontal cyclic loading can be applied to the pile cap through the horizontal electromagnetic vibration exciter.
(2) Because the invention is provided with the saturated soil liquefaction exciting device, the saturated soil contained in the laminated shearing model box can be liquefied through the vertical circulating vibration of the eccentric vibration exciter.
(3) The invention can simulate the pushing action of the lateral large deformation caused by the liquefaction of the saturated sand on the pile under the condition of an inclined field and can also simulate the inertial load of the earthquake on the pile under the condition of a horizontal field.
(4) The invention can simulate the inertial load of the earthquake on the pile under the condition of horizontal field. Cyclic loading of the stacked shear mould box can be achieved by means of electromagnetic exciters controlled by a computer 15 (the electromagnetic exciters here include both the mould box electromagnetic exciter and the horizontal electromagnetic exciter). And controlling the electromagnetic vibration exciter of the model box by the computer 15 to push each layer of frame of the laminated shearing model box to displace.
(4) The invention can be applied to the pile loading in different states, wherein the piles in different states refer to single piles or grouped piles, pile diameters, pile lengths, pile distances, the elastic modulus of the piles, the section forms of the piles, the materials of the piles and the pile end constraint types. The piles are prefabricated in advance in a factory and transported to a laboratory.
(5) The simulation device can apply variable vertical load by adopting the hydraulic jack and can also apply constant vertical load by adopting the weight 14.
In conclusion, the invention can apply horizontal load to the laminated shearing model box and vertical load and horizontal cyclic load to the pile body after the soil body in the laminated shearing model box is liquefied. The method can be used for researching the interaction characteristic of the pile and the soil, and can simulate the composite stress mechanism of the pile foundation in the horizontal liquefaction field under the earthquake condition and the composite stress state of the pile foundation in the lateral large deformation after the liquefaction of the saturated soil body under the inclined field condition.
Drawings
FIG. 1 is a front view of a first embodiment of a simulation apparatus for a composite stress mechanism of a pile foundation of a liquefied field according to the present invention;
FIG. 2 is a front view of the horizontal cyclical loading device;
FIG. 3 is a schematic view of an eccentric exciter;
FIG. 4 is a schematic view of a spring damper;
FIG. 5 is a schematic view of a vertical loading device;
FIG. 6 is a top view of the horizontal cyclical loading device;
fig. 7 is a front view of a second embodiment of the simulation device for a composite stress mechanism of a pile foundation of a liquefied field.
The names and reference numbers of the components referred to in the above figures are as follows:
the device comprises a reaction frame 1, a horizontal loading hydraulic jack 2, a vertical loading hydraulic jack 3, a horizontal electromagnetic vibration exciter 4, a laminated shearing model box 5, an eccentric vibration exciter 6, a cross beam 7, a pile body 8, a pile cap 9, a steel bottom plate 10, a spring vibration absorber 11, a steel outer sleeve 12, a conversion joint 13, a weight 14, a computer 15 and a connecting seat 16.
Detailed Description
The first embodiment is as follows: as shown in fig. 1, the present embodiment discloses a simulation device for a composite stress mechanism of a pile foundation in a liquefaction site, which is characterized in that: the device comprises a reaction frame 1 (made of hot-rolled I-shaped steel and used as a welding frame), a laminated shearing model box 5, a model box loading device, a horizontal circulating loading device, a vertical loading device, a saturated soil liquefaction exciting device and a steel outer sleeve 12;
the lower end of the reaction frame 1 is fixed on a steel bottom plate 10 (the steel bottom plate 10 is fixed on a foundation) through bolts, the vertical loading device is arranged in the reaction frame 1, the upper end of the vertical loading device is connected with an upper cross beam of the reaction frame 1 in a sliding way, the lower end of the vertical loading device is connected with the upper end surface of a steel outer sleeve 12, the pile cap 9 is fixed in a steel outer sleeve 12, the pile body 8 is embedded in the laminated shearing model box 5, the bottom of the laminated shearing model box 5 is fixed on the saturated soil liquefaction excitation device (through bolts), the saturated soil liquefaction excitation device is fixed on a steel bottom plate 10, the horizontal circulation loading device is in sliding connection with a vertical beam corresponding to the reaction frame 1, the horizontal circulation loading device is connected with a pile cap 9 through a steel outer sleeve 12, and the model box loading device is in sliding connection with the vertical beam corresponding to the reaction frame 1; when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box 5 to drive the frame body corresponding to the laminated shearing model box 5 to horizontally move; the vertical loading device, the horizontal circulating loading device, the model box loading device and the saturated soil liquefaction excitation device are respectively connected with the computer 15 through data lines.
The pile is formed by the pile body 8 and the pile cap 9.
The vertical loading device can be loaded in a loading mode of controlling displacement or stress, and the horizontal circulating loading device can be loaded in a mode of controlling amplitude, frequency and duration.
The second embodiment is as follows: as shown in fig. 5, this embodiment is further described with respect to the first embodiment, and the vertical loading device includes at least two vertical loading hydraulic jacks 3 or at least two servo dynamic control systems (prior art); the lower terminal surface of the entablature of reaction frame 1 is equipped with horizontal slide, all along left right direction vertical loading hydraulic jack 3 or servo dynamic control system's stiff end all with horizontal slide sliding connection (be equipped with slider one on every vertical loading hydraulic jack 3 or servo dynamic control system's the stiff end, slider one and horizontal slide sliding connection), all vertical loading hydraulic jack 3 or servo dynamic control system's the loading end all (through the bolt) and the up end fixed connection of steel overcoat 12.
The vertical loading hydraulic jack 3 can slide along the horizontal slideway to achieve the purpose of loading piles at different positions. In the experimental process, the loading rate of the vertical loading hydraulic jack 3 is controlled by the computer 15, and the pile cap 9 can be loaded and unloaded step by step. When the loads applied to the steel outer sleeve 12 by the two vertical loading hydraulic jacks 3 or the two servo dynamic control systems are different, the bending moment loading of the pile head can be realized.
The servo dynamic control system is an operation system capable of automatically controlling the mechanical movement of the simulation device according to the preset requirement. The servo dynamic control system controls the output quantity of the simulation device, such as displacement, rotation angle, displacement speed, acceleration, force and moment, and the action of the servo dynamic control system is to enable the output mechanical displacement (or rotation angle) to accurately track the input displacement (or rotation angle).
The third concrete implementation mode: as shown in fig. 2 and fig. 6, the present embodiment further describes a second embodiment, wherein the horizontal cyclic loading device includes a horizontal electromagnetic vibration exciter 4 (which is an existing outsourced component), a connecting seat 16, and an adapter 13 (which is an existing outsourced component); the two ends of the horizontal electromagnetic vibration exciter 4 are respectively connected with the connecting seat 16 and the adapter 13, the adapter 13 is connected with the steel outer sleeve 12, the steel outer sleeve 12 is connected with the pile cap 9, and the connecting seat 16 is in sliding connection with a vertical slide rail arranged on a corresponding upright post of the reaction frame 1 (a first sliding block in sliding fit with the vertical slide rail on the reaction frame 1 is arranged on the connecting seat 16).
The purpose of applying simple harmonic load to the pile cap 9 is achieved by applying variable amplitude alternating current to the coil in the horizontal electromagnetic vibration exciter 4.
The horizontal electromagnetic vibration exciter 4 is provided with a sensor which can control the cyclic load of the input pile cap 9.
The horizontal cyclic loading device applies cyclic load by the horizontal electromagnetic vibration exciter 4 to simulate the action of earthquake and the like on the pile.
Horizontal electromagnetic vibration exciter 4 passes through connecting seat 16 and the vertical slide sliding connection of reaction frame 1, and horizontal electromagnetic vibration exciter 4 can slide along vertical slide to the realization is loaded the stake of co-altitude department.
The adapter 13 can rotate, so that the horizontal electromagnetic vibration exciter 4 can apply stable horizontal cyclic load or vertical cyclic load to the pile cap 9, and can apply inclined load to the pile cap 9. Under the action of the adapter 13, the horizontal cyclic loading device can simulate the inertial load of the earthquake input pile under different working conditions.
The steel outer jacket 12 is bolted to the adapter 13. The horizontal electromagnetic vibration exciter 4 can achieve the purpose of applying cyclic load to the pile cap 9 through the steel outer sleeve 12. When the loads applied to the steel outer sleeve 12 by the two horizontal electromagnetic vibration exciters 4 are different, the torque loading of the pile head can be realized.
The sensor on the horizontal electromagnetic exciter 4 can accurately measure the amplitude, frequency and duration of the load applied to the pile cap 9.
Horizontal electromagnetic vibration exciter 4 can slide along vertical slide through connecting seat 16, can realize carrying out the loading to the stake of not co-altitude department. The horizontal electromagnetic vibration exciter 4 can control displacement to load and can also control acceleration to load.
The characteristics of the load applied to the pile cap 9 by the horizontal electromagnetic exciter 4 can be calculated by finite element software openneespl.
The fourth concrete implementation mode: as shown in fig. 1, the present embodiment is further described with respect to the first embodiment, and the mold box loading device comprises a plurality of horizontal loading hydraulic jacks 2 or a plurality of mold box electromagnetic exciters; the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters are all horizontally arranged, the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters are arranged in parallel up and down, vertical slideways II are arranged on vertical beams of the reaction frame 1 corresponding to the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters, and fixed ends of the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters are connected with the vertical slideways II in a sliding mode; when the model box loading device works, the horizontal loading hydraulic jack 2 or the model box electromagnetic vibration exciter is detachably connected with the corresponding frame body of the laminated shearing model box 5, and the corresponding frame body is driven to move horizontally by the horizontal loading hydraulic jack 2 or the model box electromagnetic vibration exciter.
The simulation device can simulate the pushing action of lateral large deformation to the pile caused by liquefaction of saturated sand under the condition of an inclined field, and can simulate the inertial load of the earthquake acting on the pile under the condition of a horizontal field. The cyclic loading of the stacked shear mould box 5 can be achieved by means of a mould box electromagnetic exciter controlled by a computer 15. The frequency, amplitude and duration of the load input into the laminated shear mold box 5 by the electromagnetic exciter of the mold box can be calculated by finite element software, Cyclic 1D, deepoil, soliquake 2016. And the computer 15 controls the electromagnetic vibration exciter of the model box to push each layer of frame body to displace. Displacement sensors are respectively arranged at the vertical loading hydraulic jack 3 and the horizontal loading hydraulic jack 2, so that the vertical displacement of the pile cap 9 and the horizontal displacement of the laminated shearing model box 5 can be measured.
The fifth concrete implementation mode: as shown in fig. 1, this embodiment is further described with respect to the first embodiment, and the laminated shear model box 5 includes a plurality of frames (steel frames formed by welding channel steels) and a bottom box; the plurality of frame bodies are stacked on the bottom box, four frames of each frame body and the bottom box are made of channel steel, stiffening ribs are arranged at intervals in the channel steel, and the frame bodies and the bottom box positioned at the lowest layer are connected in a rolling mode (in the two adjacent frame bodies, a rolling bearing is arranged on the lower end face of the frame body positioned at the upper part, and a rolling groove is arranged on the upper end face of the frame body positioned at the lower part; the right end (non-loading end) of each frame body is provided with a displacement sensor (capable of measuring the lateral displacement of the laminated shearing model box 5 and accurately controlling the shearing deformation of soil around the pile), and the inner peripheral side surface, the inner peripheral side surface and the inner bottom surface of the bottom box of each frame body are respectively provided with a layer of rubber membrane (in actual engineering, the duration time of an earthquake is short, the simulation device strictly controls the soil body not to be drained, in order to control the soil body not to be drained, the outer part of the soil body in the laminated shearing model box 5 is provided with a layer of rubber membrane, and the inner part of the laminated shearing model box 5 can be ensured not to be drained).
The sixth specific implementation mode: as shown in fig. 1, 3 and 4, the third embodiment is further described, and the saturated soil liquefaction excitation device includes at least one cross beam 7, at least two eccentric vibration exciters 6 (existing outsourced components), and at least two spring dampers 11 (existing outsourced components); a cross beam 7 is fixed between the two adjacent eccentric vibration exciters 6, the upper end of each eccentric vibration exciter 6 is fixedly connected with the lower end face of the bottom box of the laminated shearing model box 5 (through a bolt), each eccentric vibration exciter 6 is fixed on a corresponding spring damper 11, and all the spring dampers 11 are fixed on a steel bottom plate 10.
The eccentric vibration exciter 6 can apply vibration with the same frequency to the laminated shearing model box 5 and soil in the box, so that saturated sandy soil in the box can be liquefied.
The cross beam 7 is made of fatigue-resistant high-strength steel. The two eccentric vibration exciters 6 connected through the cross beam 7 can keep vibrating at the same frequency.
The spring exciter 11 can reduce the influence of the eccentric exciter 6 on the foundation during operation, and can make the vibration applied to the laminated shearing model box 5 by the eccentric exciter 6 more uniform.
The simulation device aims to simulate the phenomenon that the actual engineering saturated loose powder and fine sand are suddenly destroyed to be in a liquid state under the vibration action caused by earthquake, explosion and the like.
The seventh embodiment: as shown in fig. 1, this embodiment is a further description of a sixth embodiment, a resistance strain gauge is uniformly adhered to the outer wall of the pile body 8 along the axial direction, the resistance strain gauge is connected to the computer 15 through a data line, the strain of the pile body 8 is collected through a data collection system of the computer 15, and the internal stress state of the pile can be calculated through the constitutive relation of the pile;
the calculation formula is as follows:
σ＝ε·E
in the formula:
sigma-shaft stress
Strain of epsilon-pile body
E-modulus of elasticity of pile body.
The data acquisition system is existing software.
The specific implementation mode is eight: as shown in fig. 1, in the present embodiment, a seventh embodiment is further described, in which a plurality of vibrating wire type soil pressure cells are embedded in the soil around the pile body 8 in the stacked shear model box 5, and the plurality of vibrating wire type soil pressure cells are connected to the computer 15 through data lines. The vibrating wire type soil pressure cell is used for measuring the soil pressure around the pile, and the soil pressure of the soil around the pile is collected by using a data collection system of the computer 15.
The vibrating string type soil pressure boxes are arranged at certain intervals, so that the change of the soil pressure inside the soil body around the pile can be accurately measured.
The specific implementation method nine: as shown in fig. 7, the present embodiment discloses a simulation apparatus for a composite stress mechanism of a pile foundation in a liquefaction site, which includes a reaction frame 1 (made of hot rolled i-shaped steel, which is a welded frame), a stacked shear model box 5, a model box loading device, a horizontal circulation loading device, weights 14, a saturated soil liquefaction excitation device, and a steel outer sleeve 12;
the lower end of the reaction frame 1 is fixed on a steel bottom plate 10 (the steel bottom plate 10 is fixed on a foundation), a pile cap 9 is fixed in a steel outer sleeve 12, a pile body 8 is embedded in a laminated shearing model box 5, weights 14 are arranged on the upper end face of the pile cap 9, the bottom of the laminated shearing model box 5 is fixed on a saturated soil liquefaction exciting device (through bolts), the saturated soil liquefaction exciting device is fixed on the steel bottom plate 10, the horizontal cyclic loading device 4 is in sliding connection with a vertical beam corresponding to the reaction frame 1, the horizontal cyclic loading device is connected with the pile cap 9 through the steel outer sleeve 12, and the model box loading device is in sliding connection with the vertical beam corresponding to the reaction frame 1; when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box 5 to drive the frame body corresponding to the laminated shearing model box 5 to horizontally move; the horizontal circulation loading device, the model box loading device and the saturated soil liquefaction excitation device are respectively connected with the computer 15 through data lines.
The weight 14 can apply a vertical load of constant magnitude and direction at the helmet 9.
The detailed implementation mode is ten: as shown in fig. 2 and fig. 6, the present embodiment further describes a ninth embodiment, where the horizontal cyclic loading device includes a horizontal electromagnetic vibration exciter 4 (which is an existing outsourced component), a connection seat 16, and an adapter 13 (which is an existing outsourced component); the two ends of the horizontal electromagnetic vibration exciter 4 are respectively connected with the connecting seat 16 and the adapter 13, the adapter 13 is connected with the steel outer sleeve 12, the steel outer sleeve 12 is connected with the pile cap 9, and the connecting seat 16 is in sliding connection with a vertical slide rail arranged on a corresponding upright post of the reaction frame 1 (a first sliding block in sliding fit with the vertical slide rail on the reaction frame 1 is arranged on the connecting seat 16).
The purpose of applying simple harmonic load to the pile cap 9 is achieved by applying variable amplitude alternating current to the coil in the horizontal electromagnetic vibration exciter 4.
The horizontal electromagnetic vibration exciter 4 is respectively provided with a sensor which can control the cyclic load of the input pile cap 9.
The horizontal cyclic loading device applies cyclic load by the horizontal electromagnetic vibration exciter 4 to simulate the action of earthquake and the like on the pile. The horizontal electromagnetic vibration exciter 4 is connected with the upright column corresponding to the reaction frame 1 in a sliding mode through the first vertical slideway, and the horizontal electromagnetic vibration exciter 4 can slide along the first vertical slideway, so that piles at different heights can be loaded.
The adapter 13 can rotate, so that the horizontal electromagnetic vibration exciter 4 can apply stable horizontal cyclic load or vertical cyclic load to the pile cap 9, and can apply inclined load to the pile cap 9. Under the action of the adapter 13, the horizontal cyclic loading device can simulate the inertial load of the earthquake input pile under different working conditions.
The steel outer jacket 12 is bolted to the adapter 13. The horizontal electromagnetic vibration exciter 4 can achieve the purpose of applying cyclic load to the pile cap 9 through the steel outer sleeve 12.
The sensor on the horizontal electromagnetic exciter 4 can accurately measure the amplitude, frequency and duration of the load applied to the pile cap 9.
Horizontal electromagnetic vibration exciter 4 can slide along vertical slide through connecting seat 16, can realize carrying out the loading to the stake of not co-altitude department. The horizontal electromagnetic vibration exciter 4 can control displacement to load and can also control acceleration to load.
The characteristics of the load applied to the pile cap 9 by the horizontal electromagnetic exciter 4 can be calculated by corresponding finite element software openneespl.
The concrete implementation mode eleven: as shown in fig. 1, this embodiment is further explained for the ninth embodiment, and the mold box loading device comprises a plurality of horizontal loading hydraulic jacks 2 or a plurality of mold box electromagnetic exciters; the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters are all horizontally arranged, the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters are arranged in parallel up and down, vertical slideways II are arranged on vertical beams of the reaction frame 1 corresponding to the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters, and fixed ends of the horizontal loading hydraulic jacks 2 or the model box electromagnetic vibration exciters are connected with the vertical slideways II in a sliding mode; when the model box loading device works, the horizontal loading hydraulic jack 2 or the model box electromagnetic vibration exciter is detachably connected with the corresponding frame body of the laminated shearing model box 5, and the corresponding frame body is driven to move horizontally by the horizontal loading hydraulic jack 2 or the model box electromagnetic vibration exciter.
The simulation device can simulate the pushing action of lateral large deformation to the pile caused by liquefaction of saturated sand under the condition of an inclined field, and can simulate the inertial load of the earthquake acting on the pile under the condition of a horizontal field. The cyclic loading of the stacked shear mould box 5 can be achieved by means of a mould box electromagnetic exciter controlled by a computer 15. The frequency, amplitude and duration of the load input into the laminated shear mold box 5 by the electromagnetic exciter of the mold box can be calculated by the relevant finite element software, Cyclic 1D, deepoil, soliquake 2016. And the computer 15 controls the electromagnetic vibration exciter of the model box to push each layer of frame body to displace. Displacement sensors are arranged at the vertical loading hydraulic jack 3 and the horizontal loading hydraulic jack 2, so that the vertical displacement of the pile cap 9 and the horizontal displacement of the laminated shearing model box 5 can be measured.
The specific implementation mode twelve: as shown in fig. 1, this embodiment is further explained with respect to a ninth embodiment, in which the laminated shear model box 5 includes a plurality of frames (steel frames formed by welding channel steels) and a bottom box; the plurality of frame bodies are stacked on the bottom box, four frames of each frame body and the bottom box are made of channel steel, stiffening ribs are arranged at intervals in the channel steel, and the frame bodies and the bottom box positioned at the lowest layer are connected in a rolling mode (in the two adjacent frame bodies, a rolling bearing is arranged on the lower end face of the frame body positioned at the upper part, and a rolling groove is arranged on the upper end face of the frame body positioned at the lower part; the right end (non-loading end) of each frame body is provided with a displacement sensor (capable of measuring the lateral displacement of the laminated shearing model box 5 and accurately controlling the shearing deformation of soil around the pile), and the inner peripheral side surface, the inner peripheral side surface and the inner bottom surface of the bottom box of each frame body are respectively provided with a layer of rubber membrane (in actual engineering, the duration time of an earthquake is short, the simulation device strictly controls the soil body not to be drained, in order to control the soil body not to be drained, the outer part of the soil body in the laminated shearing model box 5 is provided with a layer of rubber membrane, and the inner part of the laminated shearing model box 5 can be ensured not to be drained).
The specific implementation mode is thirteen: as shown in fig. 1, 3 and 4, the present embodiment further illustrates a ninth embodiment, where the saturated soil liquefaction driving apparatus includes at least one cross beam 7, at least two eccentric vibration exciters 6 (existing outsourced components), and at least two spring dampers 11 (existing outsourced components); a cross beam 7 is fixed between the two adjacent eccentric vibration exciters 6, the upper end of each eccentric vibration exciter 6 is fixedly connected with the lower end face of the bottom box of the laminated shearing model box 5 (through a bolt), each eccentric vibration exciter 6 is fixed on a corresponding spring damper 11, and all the spring dampers 11 are fixed on a steel bottom plate 10.
The eccentric vibration exciter 6 can apply vibration with the same frequency to the laminated shearing model box 5 and soil in the box, so that saturated sandy soil in the box can be liquefied.
The cross beam 7 is made of fatigue-resistant high-strength steel. The two eccentric vibration exciters 6 connected through the cross beam 7 can keep vibrating at the same frequency.
The spring exciter 11 can reduce the influence of the eccentric exciter 6 on the foundation during operation, and can make the vibration applied to the laminated shearing model box 5 by the eccentric exciter 6 more uniform.
The simulation device aims to simulate the phenomenon that the actual engineering saturated loose powder and fine sand are suddenly destroyed to be in a liquid state under the vibration action caused by earthquake, explosion and the like.
The specific implementation mode is fourteen: as shown in fig. 1, this embodiment is a further description of a ninth embodiment, a resistance strain gauge is uniformly adhered to an outer wall of the pile body 8 along an axial direction, the resistance strain gauge is connected to the computer 15 through a data line, a data acquisition system of the computer 15 acquires strain of the pile body 8, and an internal stress state of the pile can be calculated through a constitutive relation of the pile;
the calculation formula is as follows:
σ＝ε·E
in the formula:
sigma-shaft stress
Strain of epsilon-pile body
E-modulus of elasticity of pile body.
The data acquisition system is existing software.
The concrete implementation mode is fifteen: as shown in fig. 1, this embodiment is a further description of a ninth embodiment, in which a plurality of vibrating wire type soil pressure cells are embedded in the soil around the pile body 8 in the stacked shear model box 5, and the vibrating wire type soil pressure cells are connected to a computer 15 through data lines. The vibrating wire type soil pressure cell is used for measuring the soil pressure around the pile, and the soil pressure of the soil around the pile is collected by using a data collection system of the computer 15.
The vibrating string type soil pressure boxes are arranged at certain intervals, so that the change of the soil pressure inside the soil body around the pile can be accurately measured.
The specific implementation mode is sixteen: as shown in fig. 1 to 6, the present embodiment discloses a method for implementing a simulation test of a composite stress mechanism of a pile foundation of a liquefaction site by using a simulation apparatus according to the eighth embodiment, where the method includes the following steps:
the method comprises the following steps: sticking a resistance strain gauge along the axial direction of the pile body 8, and connecting the resistance strain gauge with a computer 15 through a data line;
step two: placing a soil body prepared in advance in a laminated shearing model box 5, embedding a pile body 8 and a vibrating wire type soil pressure box in the soil body, and connecting the vibrating wire type soil pressure box to a computer 15 through a data line;
step three: inputting small-to-large vibration through the eccentric vibration exciter 6 until soil in the laminated shearing model box 5 is liquefied, and connecting a sensor on the eccentric vibration exciter 6 to a computer 15 through a data line;
step four: the computer 15 controls the vertical loading hydraulic jack 3 of the vertical loading device to apply a vertical load to the pile cap 9, controls the horizontal cyclic loading device to apply a horizontal load to the laminated shearing model box 5, and pushes the soil body in the laminated shearing model box 5 to generate shearing deformation;
step five: the computer 15 controls the horizontal cyclic loading device to apply horizontal cyclic load through the horizontal electromagnetic vibration exciter 4 connected to the pile cap 9.
The detachable connection in the invention can be a hanging connection (connection between a hook and a hanging ring) or a protruding slot arranged on the side surface of the frame body, and the execution ends of the horizontal loading hydraulic jack 2 or the electromagnetic vibration exciters of a plurality of model boxes are tightly inserted into the slot and connected through a pin shaft. All schemes that can realize the detachable connection of the horizontal loading hydraulic jack 2 or a plurality of model box electromagnetic vibration exciters and the frame body are in the protection range of the device.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention, and the present invention is not limited thereto, and any person skilled in the art can substitute or change the technical solution of the present invention and its inventive concept within the technical scope of the present invention.
Claims (16)
1. The utility model provides a compound atress mechanism analogue means of liquefaction place pile foundation which characterized in that: the device comprises a reaction frame (1), a laminated shearing model box (5), a model box loading device, a horizontal circulating loading device, a vertical loading device, a saturated soil liquefaction exciting device and a steel outer sleeve (12);
the lower end of the reaction frame (1) is fixed on the steel bottom plate (10), the vertical loading device is arranged in the reaction frame (1), the upper end of the vertical loading device is connected with the upper beam of the reaction frame (1) in a sliding way, the lower end of the vertical loading device is connected with the upper end surface of the steel outer sleeve (12), the pile cap (9) is fixed in a steel outer sleeve (12), the pile body (8) is embedded in the laminated shearing model box (5), the bottom of the laminated shearing model box (5) is fixed on a saturated soil body liquefaction excitation device, the saturated soil liquefaction excitation device is fixed on a steel bottom plate (10), the horizontal circulation loading device is connected with a vertical beam corresponding to the reaction frame (1) in a sliding way, the horizontal circulation loading device is connected with a pile cap (9) through a steel outer sleeve (12), the model box loading device is connected with the vertical beam corresponding to the reaction frame (1) in a sliding way; when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box (5) to drive the frame body corresponding to the laminated shearing model box (5) to horizontally move; the vertical loading device, the horizontal circulating loading device, the model box loading device and the saturated soil liquefaction excitation device are respectively connected with a computer (15) through data lines.
2. The device for simulating the composite stress mechanism of the pile foundation of the liquefied field according to claim 1, wherein: the vertical loading device comprises at least two vertical loading hydraulic jacks (3) or at least two servo dynamic control systems; the lower end face of an upper cross beam of the reaction frame (1) is provided with a horizontal slideway along the left-right direction, the fixed ends of all the vertical loading hydraulic jacks (3) or the servo dynamic control system are in sliding connection with the horizontal slideway, and the loading ends of all the vertical loading hydraulic jacks (3) or the servo dynamic control system are in fixed connection with the upper end face of the steel outer sleeve (12).
3. The device for simulating the composite stress mechanism of the pile foundation of the liquefied field according to claim 2, wherein: the horizontal circulating loading device comprises a horizontal electromagnetic vibration exciter (4), a connecting seat (16) and a conversion joint (13); horizontal electromagnetic vibration exciter (4) both ends are connected with connecting seat (16) and crossover sub (13) respectively, crossover sub (13) are connected with steel overcoat (12), and steel overcoat (12) are connected with pile cap (9), connecting seat (16) and the vertical slide sliding connection who sets up on the corresponding stand of reaction frame (1).
4. The device for simulating the composite stress mechanism of the pile foundation of the liquefied field according to claim 1, wherein: the model box loading device comprises a plurality of horizontal loading hydraulic jacks (2) or a plurality of model box electromagnetic vibration exciters; the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters are all horizontally arranged, the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters are arranged in parallel up and down, vertical slideways II are arranged on vertical beams of the reaction frame (1) corresponding to the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters, and fixed ends of the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters are connected with the vertical slideways II in a sliding mode; when the model box loading device works, the horizontal loading hydraulic jack (2) or the model box electromagnetic vibration exciter is detachably connected with the corresponding frame body of the laminated shearing model box (5), and the corresponding frame body is driven to move horizontally by the horizontal loading hydraulic jack (2) or the model box electromagnetic vibration exciter.
5. The device for simulating the composite stress mechanism of the pile foundation of the liquefied field according to claim 1, wherein: the laminated shearing model box (5) comprises a plurality of frame bodies and a bottom box; the frame bodies are stacked on the bottom box, each frame body and four frames of the bottom box are made of channel steel, stiffening ribs are arranged in the channel steel at intervals, the frame bodies and the bottom box positioned at the lowest layer are connected in a rolling mode, and cylindrical steel stand columns are fixed on the front outer side surface and the rear outer side surface of the box bottom of the stacked shearing model box (5) so as to limit displacement of the frame bodies in the front-rear direction; the right end of each frame body is provided with a displacement sensor, and the inner peripheral side surface of each frame body, the inner peripheral side surface of the bottom box and the inner bottom surface of each bottom box are provided with a layer of rubber film.
6. The device of claim 3, wherein the device comprises: the saturated soil liquefaction excitation device comprises at least one cross beam (7), at least two eccentric vibration exciters (6) and at least two spring shock absorbers (11); a cross beam (7) is fixed between the two adjacent eccentric vibration exciters (6), the upper end of each eccentric vibration exciter (6) is fixedly connected with the lower end face of the bottom box of the laminated shearing model box (5), each eccentric vibration exciter (6) is fixed on a corresponding spring damper (11), and all the spring dampers (11) are fixed on a steel bottom plate (10).
7. The device for simulating the composite stress mechanism of the pile foundation of the liquefied field according to claim 6, wherein: resistance strain gauges are uniformly adhered to the outer wall of the pile body (8) along the axial direction and connected with a computer (15) through a data line, strain of the pile body (8) is acquired through a data acquisition system of the computer (15), and the internal stress state of the pile can be calculated through the constitutive relation of the pile;
the calculation formula is as follows:
σ＝ε·E
in the formula:
sigma-shaft stress
Strain of epsilon-pile body
E-modulus of elasticity of pile body.
8. The device of claim 7, wherein the device comprises: a plurality of vibrating wire type soil pressure boxes are buried in soil around the pile body (8) in the laminated shearing model box (5) and are connected with a computer (15) through data lines. The vibrating wire type soil pressure box is used for measuring the soil pressure around the pile, and the soil pressure of the soil around the pile is collected by a data collection system of a computer (15).
9. The utility model provides a compound atress mechanism analogue means of liquefaction place pile foundation which characterized in that: comprises a reaction frame (1), a laminated shearing model box (5), a model box loading device, a horizontal circulating loading device, weights (14), a saturated soil liquefaction exciting device and a steel outer sleeve (12);
the lower end of the reaction frame (1) is fixed on a steel bottom plate (10), a pile cap (9) is fixed in a steel outer sleeve (12), a pile body (8) is embedded into a laminated shearing model box (5), weights (14) are arranged on the upper end face of the pile cap (9), the bottom of the laminated shearing model box (5) is fixed on a saturated soil liquefaction exciting device, the saturated soil liquefaction exciting device is fixed on the steel bottom plate (10), a horizontal circulating loading device (4) is in sliding connection with a vertical beam corresponding to the reaction frame (1), the horizontal circulating loading device is connected with the pile cap (9) through the steel outer sleeve (12), and the model box loading device is in sliding connection with the vertical beam corresponding to the reaction frame (1); when the model box loading device works, the model box loading device is detachably connected with the frame body corresponding to the laminated shearing model box (5) to drive the frame body corresponding to the laminated shearing model box (5) to horizontally move; the horizontal circulation loading device, the model box loading device and the saturated soil liquefaction excitation device are respectively connected with a computer (15) through data lines.
10. The device of claim 9, wherein the device comprises: the horizontal circulating loading device comprises a horizontal electromagnetic vibration exciter (4), a connecting seat (16) and a conversion joint (13); horizontal electromagnetic vibration exciter (4) both ends are connected with connecting seat (16) and crossover sub (13) respectively, crossover sub (13) are connected with steel overcoat (12), and steel overcoat (12) are connected with pile cap (9), connecting seat (16) and the vertical slide sliding connection who sets up on the corresponding stand of reaction frame (1).
11. The device of claim 9, wherein the device comprises: the model box loading device comprises a plurality of horizontal loading hydraulic jacks (2) or a plurality of model box electromagnetic vibration exciters; the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters are all horizontally arranged, the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters are arranged in parallel up and down, vertical slideways II are arranged on vertical beams of the reaction frame (1) corresponding to the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters, and fixed ends of the horizontal loading hydraulic jacks (2) or the model box electromagnetic vibration exciters are connected with the vertical slideways II in a sliding mode; when the model box loading device works, the horizontal loading hydraulic jack (2) or the model box electromagnetic vibration exciter is detachably connected with the corresponding frame body of the laminated shearing model box (5), and the corresponding frame body is driven to move horizontally by the horizontal loading hydraulic jack (2) or the model box electromagnetic vibration exciter.
12. The device of claim 9, wherein the device comprises: the laminated shearing model box (5) comprises a plurality of frame bodies and a bottom box; the frame bodies are stacked on the bottom box, each frame body and four frames of the bottom box are made of channel steel, stiffening ribs are arranged in the channel steel at intervals, the frame bodies and the bottom box positioned at the lowest layer are connected in a rolling mode, and cylindrical steel stand columns are fixed on the front outer side surface and the rear outer side surface of the box bottom of the stacked shearing model box (5) so as to limit displacement of the frame bodies in the front-rear direction; the right end of each frame body is provided with a displacement sensor, and the inner peripheral side surface of each frame body, the inner peripheral side surface of the bottom box and the inner bottom surface of each bottom box are provided with a layer of rubber film.
13. The device of claim 9, wherein the device comprises: the saturated soil liquefaction excitation device comprises at least one cross beam (7), at least two eccentric vibration exciters (6) and at least two spring shock absorbers (11); a cross beam (7) is fixed between the two adjacent eccentric vibration exciters (6), the upper end of each eccentric vibration exciter (6) is fixedly connected with the lower end face of the bottom box of the laminated shearing model box (5), each eccentric vibration exciter (6) is fixed on a corresponding spring damper (11), and all the spring dampers (11) are fixed on a steel bottom plate (10).
14. The device of claim 9, wherein the device comprises: resistance strain gauges are uniformly adhered to the outer wall of the pile body (8) along the axial direction and connected with a computer (15) through a data line, strain of the pile body (8) is acquired through a data acquisition system of the computer (15), and the internal stress state of the pile can be calculated through the constitutive relation of the pile;
the calculation formula is as follows:
σ＝ε·E
in the formula:
sigma-shaft stress
Strain of epsilon-pile body
E-modulus of elasticity of pile body.
15. The device of claim 9, wherein the device comprises: a plurality of vibrating wire type soil pressure boxes are buried in soil around the pile body (8) in the laminated shearing model box (5) and are connected with a computer (15) through data lines.
16. A simulation test method for realizing a composite stress mechanism of a liquefied field pile foundation by using the simulation device of claim 8 is characterized by comprising the following steps of: the method comprises the following steps:
the method comprises the following steps: a resistance strain gauge is pasted along the axial direction of the pile body (8) and is connected with a computer (15) through a data line;
step two: placing a soil body prepared in advance in a laminated shearing model box (5), embedding a pile body (8) and a vibrating wire type soil pressure box in the soil body, and connecting the vibrating wire type soil pressure box to a computer (15) through a data line;
step three: inputting small-to-large vibration through an eccentric vibration exciter (6) until soil in the laminated shearing model box (5) is liquefied, and connecting a sensor on the eccentric vibration exciter (6) to a computer (15) through a data line;
step four: the computer (15) controls a vertical loading hydraulic jack (3) of the vertical loading device to apply a vertical load to the pile cap (9), controls the horizontal circulating loading device to apply a horizontal load to the laminated shearing model box (5), and pushes a soil body in the laminated shearing model box (5) to generate shearing deformation;
step five: the computer (15) controls the horizontal cyclic loading device to apply horizontal cyclic load through a horizontal electromagnetic vibration exciter (4) connected to the pile cap (9).
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114112273A (en) * | 2021-12-27 | 2022-03-01 | 安徽工程大学 | Indoor model of pile soil system and transverse vibration experiment modal analysis test system thereof |
| CN115492172A (en) * | 2022-07-26 | 2022-12-20 | 长沙理工大学 | Device and method for testing influence of traffic load on pile net composite foundation power |
| CN116519486A (en) * | 2023-05-29 | 2023-08-01 | 广州建筑股份有限公司 | Negative excess pore water pressure model test device and method for following tubular pile drilling while drilling |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101532931A (en) * | 2009-04-17 | 2009-09-16 | 中国科学院武汉岩土力学研究所 | Experimental method of simulating dynamic and static load and device thereof |
| CN102367674A (en) * | 2011-11-08 | 2012-03-07 | 北京工业大学 | Suspension type multi-dimensional input horizontal multi-directional shearing model casing device |
| CN107202707A (en) * | 2017-06-09 | 2017-09-26 | 北京工业大学 | Structure large-scale pseudo static testing device and method under a kind of soil |
| CN108442307A (en) * | 2017-12-26 | 2018-08-24 | 广西大学 | Soil layer dependent variable measurement method in a kind of laminar shear model clay case and its case |
| CN108797655A (en) * | 2017-04-26 | 2018-11-13 | 黄河水利职业技术学院 | A kind of multi-functional soil body thixotropy and the anti-liquefaction functional simulation device of pile foundation |
| CN210954031U (en) * | 2019-11-04 | 2020-07-07 | 西南交通大学 | Loading device for simulating deep saturated sandy soil liquefaction vibration table experiment |
| CN211401595U (en) * | 2020-01-07 | 2020-09-01 | 福州大学 | Improved structure of rigidity test soil box |
| CN111648415A (en) * | 2020-05-29 | 2020-09-11 | 河海大学 | Device and method for testing ultra-long-term vibration characteristics of rock-socketed single pile |
| CN112160353A (en) * | 2020-09-01 | 2021-01-01 | 温州大学 | Pile-soil interaction indoor test device under combined cyclic loading effect and installation method |
-
2021
- 2021-03-23 CN CN202110309529.1A patent/CN113049395A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101532931A (en) * | 2009-04-17 | 2009-09-16 | 中国科学院武汉岩土力学研究所 | Experimental method of simulating dynamic and static load and device thereof |
| CN102367674A (en) * | 2011-11-08 | 2012-03-07 | 北京工业大学 | Suspension type multi-dimensional input horizontal multi-directional shearing model casing device |
| CN108797655A (en) * | 2017-04-26 | 2018-11-13 | 黄河水利职业技术学院 | A kind of multi-functional soil body thixotropy and the anti-liquefaction functional simulation device of pile foundation |
| CN107202707A (en) * | 2017-06-09 | 2017-09-26 | 北京工业大学 | Structure large-scale pseudo static testing device and method under a kind of soil |
| CN108442307A (en) * | 2017-12-26 | 2018-08-24 | 广西大学 | Soil layer dependent variable measurement method in a kind of laminar shear model clay case and its case |
| CN210954031U (en) * | 2019-11-04 | 2020-07-07 | 西南交通大学 | Loading device for simulating deep saturated sandy soil liquefaction vibration table experiment |
| CN211401595U (en) * | 2020-01-07 | 2020-09-01 | 福州大学 | Improved structure of rigidity test soil box |
| CN111648415A (en) * | 2020-05-29 | 2020-09-11 | 河海大学 | Device and method for testing ultra-long-term vibration characteristics of rock-socketed single pile |
| CN112160353A (en) * | 2020-09-01 | 2021-01-01 | 温州大学 | Pile-soil interaction indoor test device under combined cyclic loading effect and installation method |
Non-Patent Citations (1)
| Title |
|---|
| 刘春辉 等: "《液化侧扩流场地桩基地震反应分析与抗震设计方法研究》", 30 November 2019, 中国建材工业出版社 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114112273A (en) * | 2021-12-27 | 2022-03-01 | 安徽工程大学 | Indoor model of pile soil system and transverse vibration experiment modal analysis test system thereof |
| CN115492172A (en) * | 2022-07-26 | 2022-12-20 | 长沙理工大学 | Device and method for testing influence of traffic load on pile net composite foundation power |
| CN115492172B (en) * | 2022-07-26 | 2024-04-09 | 长沙理工大学 | Device and method for testing influence of traffic load on pile-net composite foundation power |
| CN116519486A (en) * | 2023-05-29 | 2023-08-01 | 广州建筑股份有限公司 | Negative excess pore water pressure model test device and method for following tubular pile drilling while drilling |
| CN116519486B (en) * | 2023-05-29 | 2024-03-08 | 广州建筑股份有限公司 | Negative excess pore water pressure model test device and method for following tubular pile drilling while drilling |
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