Frozen soil evolution test device and method under static and dynamic loading

Abstract

The invention provides a frozen soil layer evolution test device and method under static and dynamic loading, and the device comprises a frozen soil box body which comprises a first region and a second region surrounding the first region, the first region is provided with a frozen soil model which simulates the layering of a frozen soil structure, and the second region is provided with a temperature adjustment device which is used for simulating the change of environment temperature; the second area provides a deformation space of the frozen soil model; the stress device is used for applying dead load force and dynamic load force to a preset position of the frozen soil model; the observation data acquisition equipment is arranged on the slope side of the frozen soil model box and is used for acquiring an evolution image of the frozen soil model; the parameter acquisition equipment comprises internal parameter acquisition equipment and external parameter acquisition equipment, the internal parameter acquisition equipment is arranged in the frozen soil model and used for acquiring internal parameters of different structural layers of the frozen soil model, and the external parameter acquisition equipment is arranged outside the frozen soil model and used for acquiring surface deformation parameters of the frozen soil model.

Description

Technical Field

[0001] The present application relates to the technical field of frozen soil evolution, and in particular to a frozen soil layer evolution test device and method under static and dynamic loading. Background Art

[0002] Globally, permafrost areas account for about 25% of the land surface. In my country, due to the geographical trend of step-like rise from east to west, the western region is at a high altitude, and the temperature in high-altitude areas is generally low. Under the combined effect of geographical trend and temperature, a large number of frozen soil structures are distributed for a long time, especially in plateau areas where there are a large number of frozen soil slopes. At present, the area of ​​permafrost in my country accounts for about 2.15 million square kilometers. At present, due to the influence of climate warming, the degradation trend of permafrost is obvious worldwide. There is a strong cementation between ice and solid particles in frozen soil, which leads to large mechanical parameters such as cohesion, internal friction angle, Poisson's ratio and deformation modulus of frozen soil. At the same time, frozen soil has rheological properties, and its instantaneous strength is much greater than the long-term strength, so frozen soil has the characteristics of creep. In addition, frozen soil is a product of environmental changes, and it is particularly sensitive to temperature changes. Any form of heat will affect the ice content (or water content) in frozen soil, and then affect its physical and mechanical properties. Therefore, as global temperatures rise, a large amount of permafrost will degrade and leave a large number of porous structures, causing its strength and stability to drop sharply, which may trigger large-scale landslide disasters. The subsequent disaster chain will have the hidden dangers of blocking main river channels, changing terrain, and destroying the ecology.

[0003] Therefore, it is necessary to conduct intuitive and effective observation and analysis on the early destructive strain accumulation process inside the frozen soil structure in order to cope with the disasters brought by rising temperatures to the frozen soil structure. Summary of the invention

[0004] In view of this, the purpose of the present application is to propose a device and method for testing the evolution of frozen soil layers under static and dynamic loading that overcomes the above problems or at least partially solves the above problems.

[0005] Based on the above purpose, the first aspect of the present application provides a frozen soil evolution test device under static and dynamic loading, comprising:

[0006] A frozen soil box, comprising a first area and a second area surrounding the first area, wherein the first area is provided with a frozen soil model, the frozen soil model simulates the stratification of the frozen soil structure, the second area is provided with a temperature regulating device for simulating the change of ambient temperature, and the second area provides a deformation space for the frozen soil model;

[0007] A stress device, arranged above the frozen soil box, for applying a constant load and a dynamic load to a preset position of the frozen soil model;

[0008] The image acquisition devices include at least two, which are respectively arranged on the slope side of the frozen soil model box, and the observation directions of the at least two image acquisition devices are perpendicular to each other on the horizontal plane, and are used to acquire the evolution image of the frozen soil model;

[0009] A parameter acquisition device, comprising an internal parameter acquisition device and an external parameter acquisition device, wherein the internal parameter acquisition device is arranged inside the frozen soil model and is used to acquire internal parameters of different structural layers of the frozen soil model, and the external parameter acquisition device is arranged outside the frozen soil model and is used to acquire surface deformation parameters of the frozen soil model;

[0010] The structural layers of the frozen soil model are all composed of transparent soil.

[0011] Optionally, a control device is also included, which is respectively connected to the stress device, the temperature adjustment device, the image acquisition device and the parameter acquisition device, and is used to control the stress device and the temperature adjustment device respectively, and to summarize the evolution image of the image acquisition device and the internal parameters and surface deformation parameters of the parameter acquisition device.

[0012] Optionally, the stress device includes:

[0013] A vertically arranged load-bearing column, a first cross beam is provided between the tops of the load-bearing columns arranged along the first direction, a first longitudinal beam is provided between the tops of the load-bearing columns arranged along the second direction, a first sliding sleeve is sleeved on the adjacent first cross beams or first longitudinal beams, a connecting beam is provided between the first sliding sleeves, a second sliding sleeve is sleeved on the connecting beam, a telescopic device is provided vertically downwardly on the second sliding sleeve, a load-bearing plate is provided on one end of the telescopic device away from the second sliding sleeve, and a side of the load-bearing plate away from the telescopic device is in contact with the upper surface of the frozen soil model.

[0014] Optionally, the frozen soil box includes:

[0015] A support frame, the support frame forming the outline of the box;

[0016] A bottom plate, arranged on the bottom surface of the supporting frame;

[0017] A transparent window is arranged on the side of the supporting frame and is used to provide a collection window for the image collection device.

[0018] Optionally, a thermal insulation cover is provided on the top of the support frame to isolate the interior of the frozen soil box from the outside temperature; an opening corresponding to the preset position and adapted to the telescopic device is provided through the thermal insulation cover.

[0019] Optionally, the external parameter acquisition device includes: a plurality of profile imaging devices and a plurality of surface displacement measurement devices;

[0020] A plurality of the profile imaging devices are arranged on the slope side of the frozen soil model and connected to the image acquisition device, and are used to acquire profile imaging of the frozen soil model;

[0021] The multiple surface displacement measuring devices include a fixed end and a telescopic end telescopically connected to the fixed end, the fixed end is fixed in the frozen soil box, and the end of the telescopic end away from the fixed end abuts against different slope sides of the frozen soil model.

[0022] Optionally, the internal parameter acquisition equipment includes: a stress gauge, an earth pressure gauge, a displacement gauge and a pore water pressure gauge; the stress gauge, the earth pressure gauge and the displacement gauge are evenly distributed in different structural layers of the frozen soil model, and the pore water pressure gauge is arranged in the pores of the frozen soil model;

[0023] The stress gauge is used to measure the constant load and dynamic load of the frozen soil model;

[0024] The soil pressure gauge is used to measure the change of single-point pressure intensity of different structural layers in the frozen soil model during its evolution;

[0025] The displacement meter is used to measure the single-point displacement data of different structural layers in the frozen soil model during its evolution;

[0026] The pore water pressure meter is used to measure the change of pore water pressure during the evolution of the frozen soil model.

[0027] Optionally, the internal parameter acquisition device further includes: a distributed acquisition element;

[0028] The distributed collection element is provided in each layer of the structural layer of the frozen soil model, and the extension direction of the distributed collection element is the same as the extension direction of each layer in the structural layer of the frozen soil model;

[0029] The distributed acquisition elements are used to collect the overall displacement data and pressure intensity changes of each layer in the structural stratification of the frozen soil model.

[0030] The second aspect of the present application provides a method for testing the evolution of a frozen soil layer under static and dynamic loading, which is applicable to the test device for the evolution of a frozen soil layer under static and dynamic loading described in the first aspect, comprising:

[0031] Using the temperature regulating device to simulate the change of ambient temperature;

[0032] Using the stress device to apply a constant load and a dynamic load to a preset position of the frozen soil model;

[0033] Using an image acquisition device to acquire evolution images of the frozen soil model under the action of a constant load and a dynamic load;

[0034] The internal parameters and surface deformation parameters of different structural layers of the frozen soil model are collected using parameter collection equipment.

[0035] Optionally, the evolution images of the image acquisition device and the internal parameters and surface deformation parameters of the parameter acquisition device are summarized to determine the displacement and pressure intensity changes of different structural layers of the frozen soil model during the evolution process.

[0036] From the above, it can be seen that the frozen soil layer evolution test device and method under static and dynamic loading provided by the present application use transparent soil material as the material of the frozen soil model. In addition to observing the displacement caused by the surface deformation of the frozen soil model, it realizes the intuitive observation of the early disease pores and load evolution process inside the frozen soil model. In addition to intuitively observing the evolution of the frozen soil model soil, it also intuitively observes the seepage of water under low-temperature freezing or freeze-thaw cycle conditions. At the same time, the temperature regulating device is used to simulate the ambient temperature to determine the evolution process of the frozen soil model at the ambient temperature. The stress device is used to simulate the constant load force of the soil constant load and the dynamic load force of the traffic dynamic load, and the pores in the soil model and the disaster evolution chain process of different structural layers during the strain process are determined. Visual observation is performed to prevent frozen soil disasters.

[0037] At the same time, the second area of ​​the frozen soil box is used to provide a deformation space for the frozen soil model, so as to more accurately determine the disaster process and flow direction during the frozen soil disaster.

[0038] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 Schematic diagram of a frozen soil evolution test device under static and dynamic loading according to an embodiment of the present application;

[0041] Figure 2 A schematic diagram of a stress device according to an embodiment of the present application;

[0042] Figure 3 This is a schematic diagram of the internal layout of the frozen soil box in an embodiment of the present application;

[0043] Figure 4 This is a schematic diagram of water seepage in a frozen soil structure dam according to an embodiment of the present application;

[0044] Figure 5 This is a schematic diagram of solid water melting seepage in a frozen soil slope according to an embodiment of the present application;

[0045] Figure 6 This is a flow chart of the experimental method for the evolution of frozen soil layers under static and dynamic loading according to an embodiment of the present application.

[0046] Illustrations: frozen soil box 1, frozen soil model 11, supporting frame 12, transparent window 13, thermal insulation top cover 14, opening 15, temperature regulating device 16, load-bearing column 21, first cross beam 22, first longitudinal beam 23, first sliding sleeve 24, connecting beam 25, second sliding sleeve 26, telescopic device 27, load-bearing plate 28, image acquisition device 3, profile imaging device 41, surface displacement measuring device 42, fixed end 43, telescopic end 44, stress gauge 45, earth pressure gauge 46, displacement gauge 47, pore water pressure gauge 48, distributed collection element 49, control device 5, tracer particles 61, seepage water body 62. DETAILED DESCRIPTION

[0047] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0048] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0049] Frozen soil disasters are mainly caused by the gradual accumulation of internal strain or pore structure of the internal structure of frozen soil under conditions such as temperature, displacement, gravity, and water ice deformation. However, only when the internal damage of the frozen soil structure accumulates to a certain extent can a more obvious change be observed externally. In related technologies, the evolution of frozen soil is mainly studied through external observation, which cannot intuitively and effectively obtain the image information of the early deformation or pore deformation of the internal structure of frozen soil. There is a large amount of solid or liquid water inside the frozen soil structure, which is more sensitive to temperature than ordinary soil. In addition to the influence of temperature itself on the frozen soil structure, it also includes the changes in the porosity, water content or other physical and mechanical properties of the frozen soil structure caused by the ice-water phase change. Therefore, the frozen soil structure disaster involves the coupling of multiple disaster-causing factors and a complex chain destruction process.

[0050] Therefore, the present application provides a device and method for testing the evolution of frozen soil layers under static and dynamic loading, with the aim of comprehensively considering disaster-causing factors such as ambient temperature, evolution time, external load, internal porosity, internal strain, etc., while achieving the summary of frozen soil evolution by using internal deformation parameters, external deformation parameters and evolution images of the soil body, completing non-invasive measurement of internal deformation of frozen soil, and providing technical support for revealing the deformation and failure mechanism of geotechnical engineering.

[0051] refer to Figure 1 , Figure 2 , Figure 3 As shown, the frozen soil layer evolution test device under static and dynamic loading of an embodiment of the present application includes: a frozen soil box 1, including a first area and a second area surrounding the first area, the first area is provided with a frozen soil model 11, the frozen soil model 11 simulates the frozen soil structure stratification, the second area is provided with a temperature regulating device 16 for simulating environmental temperature changes, and the second area provides a deformation space for the frozen soil model 11.

[0052] In some exemplary embodiments, the permafrost model 11 simulates an actual permafrost structure, and the permafrost structure stratification may include a freeze-thaw layer and a permafrost layer, wherein both the freeze-thaw layer and the permafrost layer include corresponding ice and ice-filled pores.

[0053] The frozen soil box 1 is divided into a first area and a second area, and a temperature regulating device 16 is arranged in the second area, wherein the frozen soil model 11 located in the first area and the temperature regulating device 16 located in the second area are not in direct contact, and the temperature regulating device 16 uses the air in the second area as a medium to achieve temperature regulation, which meets the freezing conditions of the actual frozen soil. At the same time, the temperature regulating device 16 adjusts the temperature increase, which also meets the temperature warming conditions brought by the climate through the air, and realizes effective simulation of the ambient temperature. In addition, according to the characteristics of frozen soil thawing, frozen soil has extreme sensitivity to temperature, rheology, and frost heave and thaw settlement characteristics. The main purpose of this application is to determine the deformation and strength changes under the conditions of climate warming, use the second area to provide a deformation space for the frozen soil model 11, and use the deformation of the frozen soil model 11 in the deformation space to determine the displacement and strength changes of the frozen soil.

[0054] The size of the second area can be specifically set according to actual conditions. For example, the higher the simulated ambient temperature change is, the larger the second area is.

[0055] At the same time, when the temperature regulating device 16 simulates the change of ambient temperature, the frozen soil box 1 is relatively isolated from the outside environment, thereby reducing the influence of the outside environment temperature.

[0056] In some embodiments, the frozen soil model 11 is made of transparent soil. In addition to studying the displacement caused by the surface deformation of the frozen soil structure, the purpose of this application is also to study the internal deformation of the frozen soil structure. Whether it is soil or stone, the frozen soil structure formed by it cannot be observed and studied in real time inside. For the frozen soil structure, only when the internal damage accumulates to a certain extent, can more obvious changes be observed outside. Therefore, it is impossible to correspond the displacement and damage caused by the early internal deformation to the external changes. Only by setting up corresponding detection instruments inside, it is also impossible to fully display all the changes inside. In view of the current climate warming, the strong academic background of the need to control the potential disasters of frozen soil and the complex disaster chain process in the process of weakening the strength of the frozen soil structure or the deformation, it is necessary to propose a highly visualized, from the inside out, and precisely controllable frozen soil full-process disaster evolution process for the relevant disasters of the frozen soil structure.

[0057] Transparent soil technology is a technology that makes the soil body obtain transparent characteristics by controlling the refractive index of pore liquid and solid particles. When the refractive index of solid particles is consistent with that of pore liquid, the whole two-phase body will present a transparent state, wherein the refractive index of transparent soil particles is constant, and the refractive index is matched by adjusting the ratio of pore liquids with different refractive indices, and saturated under vacuum conditions, thereby forming an artificial synthetic transparent soil material similar to the structure and properties of natural soil. At the same time, the morphology or structure of the transparent soil model is analyzed in combination with particle image velocimetry (PIV) or digital image correlation technology (DIC), and the specific morphological change characteristics of the soil body structure at different stages of destruction are obtained. However, transparent soil technology has not yet been applied to experiments or research in fields related to freeze-thaw, and there is no internal visualization experimental condition for observation in the field of frozen soil disasters. The embodiment of the present application uses transparent soil as the material of the frozen soil model 11. During the evolution of the frozen soil model 11, in addition to being able to observe external changes, the internal changes can also be displayed very intuitively through the image of internal changes.

[0058] In some exemplary embodiments, the transparent soil may be quartz sand, fumed silica, or other materials.

[0059] The stress device is arranged above the frozen soil box 1 and is used to apply a constant load and a dynamic load to a preset position of the frozen soil model 11 .

[0060] In this embodiment, the frozen soil structure also has corresponding infrastructure in the actual scene, such as transportation facilities such as roads and railways. At the same time, the soil, stones, etc. in the frozen soil structure also have a certain gravity, and the vehicles running on the transportation facilities above it, such as cars and trains, will also bring external gravity to the frozen soil structure. If the soil dead load and traffic dynamic load cannot be actually simulated, the displacement and strength changes caused by the actual deformation of the frozen soil during the evolution process cannot be determined. This application applies a constant load force and a dynamic load force to the frozen soil model 11 through a stress device to simulate the soil dead load and traffic dynamic load.

[0061] It should be noted that for different scenarios, the positions of the constant load and dynamic load of frozen soil are different, and the corresponding preset positions are determined according to the frozen soil load in different scenarios. For example, as an embodiment of the present application, the preset position is the upper surface of the frozen soil model 11.

[0062] The image acquisition devices 3 include at least two, which are respectively arranged on the slope side of the frozen soil model 11, and the observation directions of the at least two image acquisition devices 3 are perpendicular to each other in the horizontal plane, so as to acquire the evolution image of the frozen soil model 11.

[0063] In some exemplary embodiments, the image acquisition device 3 can be a CCD camera, a thermal imaging device, an X-ray imaging device, a radar wave interference imaging device, etc. As long as the imaging technology can be used to acquire the evolution image, no specific limitation is made here.

[0064] The rheological properties of frozen soil and the characteristics of frost heave and thaw settlement, in the process of frozen soil thawing disaster, mainly the frozen soil slopes are sharply reduced in strength and stability, causing landslide disasters. Accordingly, the acquisition of evolution images on the slope side of the frozen soil model 11 can more intuitively determine the structural changes of the frozen soil model 11. Further, the frozen soil model 11 uses transparent soil, and the image acquisition device 3 can also intuitively acquire images of the internal deformation of the frozen soil structure on different slope sides in addition to acquiring displacement-related images caused by the surface deformation of the frozen soil model 11. By combining the internal deformation image with the surface deformation image, the displacement caused by the early internal deformation corresponds to the external deformation. Then, in the actual scene, the internal deformation image can also be inferred from the external deformation image corresponding to the external deformation, thereby determining the internal early deformation of the frozen soil and preventing possible frozen soil disasters.

[0065] Furthermore, at least two image acquisition devices 3 are used to acquire evolutionary images of the slope sides of at least two directions of the frozen soil model 11, and the correspondence between the internal deformation image and the surface deformation image of the frozen soil on different slope sides is analyzed to avoid the randomness of the correspondence between the internal deformation image and the surface deformation image on a single slope side, thereby increasing the accuracy of the surface deformation caused by the early deformation inside the frozen soil.

[0066] The parameter collection equipment includes an internal parameter collection equipment and an external parameter collection equipment. The internal parameter collection equipment is arranged inside the frozen soil model 11 and is used to collect internal parameters of different structural layers of the frozen soil model 11. The external parameter collection equipment is arranged outside the frozen soil model 11 and is used to collect surface deformation parameters of the frozen soil model 11.

[0067] The image acquisition device 3 can only roughly determine the displacement caused by the evolution process of the frozen soil model 11 under high temperature conditions through the corresponding internal deformation images and surface deformation images, but the strength changes therein cannot be effectively known. In the case of the strength position during the frozen soil evolution process, it is also impossible to carry out corresponding infrastructure construction on it, and it is also impossible to know whether the strength changes may bring new natural disaster problems in the future, such as more prone to landslides. Therefore, while using the image acquisition device 3 to intuitively observe the evolution images, it is also necessary to further determine the intensity data of the corresponding evolution images during the specific evolution process.

[0068] The internal parameters of different structural layers are collected by the internal parameter acquisition device, and the displacement parameters in the internal parameters correspond to the deformation in the evolution image, and the pressure parameters in the internal parameters correspond to the evolution image to determine the intensity change of the evolution image in the corresponding deformation. The surface deformation parameters are collected by the external parameter acquisition device, and the surface deformation of the frozen soil model 11 is accurately collected. Compared with the evolution image collected by the image acquisition device 3, it is more accurate, and further verified with the surface deformation image in the evolution image, so that the disaster analysis that may be caused by the relevant parameters in the high temperature evolution process of frozen soil is more accurate.

[0069] In some optional embodiments, the internal parameters include parameters related to strength changes of the frozen soil model 11 during its evolution and internal displacement parameters.

[0070] In some embodiments, a control device 5 is also included, which is respectively connected to the stress device, the temperature adjustment device 16, the image acquisition device 3 and the parameter acquisition device, and is used to control the stress device and the temperature adjustment device 16 respectively, and to summarize the evolution image of the image acquisition device 3 and the internal parameters and surface deformation parameters of the parameter acquisition device.

[0071] Among them, the control device 5 can be connected to the stress device, the temperature adjustment device 16, the image acquisition device 3 and the parameter acquisition device by wire, or by wireless connection such as 4G, 5G, WiFi, etc., which is not specifically limited in this embodiment.

[0072] The control device 5 is used to directly control the stress device to apply a constant load and a dynamic load to the preset position of the frozen soil model 11, so that the constant load carried by the frozen soil model 11 conforms to the soil constant load in the frozen soil structure, and the dynamic load conforms to the traffic dynamic load on the frozen soil structure. The temperature regulating device 16 is controlled to simulate the change of ambient temperature, so that the frozen soil evolves from a frozen state to a thawed state. The control device 5 summarizes the evolution image collected by the image acquisition device 3 and the internal parameters and surface deformation parameters collected by the parameter acquisition device, collects the internal deformation image and the surface deformation image of the frozen soil model 11 from the evolution image, collects the internal parameters and the surface deformation parameters from the parameter acquisition device, and uses the internal deformation image and the internal parameters to mutually verify each other, and reflects the strength change caused by the internal deformation through the internal parameters. At the same time, the displacement caused by the internal deformation is more accurately measured, and the surface deformation parameters and the surface deformation image are mutually verified, and the displacement caused by the surface deformation is accurately reflected through the surface deformation parameters.

[0073] During the whole process, for the frozen soil model 11, both the internal deformation and the surface deformation in the evolution image are visualized. The internal parameters and surface deformation parameters not only accurately reflect the specific displacement caused by the internal deformation and surface deformation, but also reflect the strength changes caused by the deformation. The surface deformation parameters reflect the specific displacement caused by the surface deformation. In addition, the impact of the early internal deformation on the surface deformation can be analyzed through summary, and the frozen soil evolution disaster can be effectively prevented.

[0074] In some embodiments, reference Figure 1 and Figure 2 As shown, the stress device includes: vertically arranged bearing columns 21, a first cross beam 22 is provided between the top ends of the bearing columns 21 arranged along the first direction, a first longitudinal beam 23 is provided between the top ends of the bearing columns 21 arranged along the second direction, first sliding sleeves 24 are provided on adjacent cross beams or longitudinal beams, connecting beams 25 are provided between the first sliding sleeves 24, a second sliding sleeve 26 is sleeved on the connecting beam 25, a telescopic device 27 is provided vertically downwardly on the second sliding sleeve 26, a bearing plate 28 is provided at one end of the telescopic device 27 away from the second sliding sleeve 26, and the side of the bearing plate 28 away from the telescopic device 27 is in contact with the upper surface of the frozen soil model 11.

[0075] In some exemplary embodiments, the first direction is Figure 1 The X direction is shown in Figure 1 Correspondingly, the first direction can also be Figure 1 The Y direction shown in the figure, the second direction can also be Figure 1 The X direction shown in .

[0076] In some exemplary embodiments, the telescopic device 27 can be an electric telescopic rod, a hydraulic telescopic rod, or other telescopic devices 27, as long as it can achieve telescopic and provide corresponding constant load and dynamic load, and the present application does not make specific limitations here.

[0077] In this embodiment, different frozen soil models 11 are provided for different frozen soil structures, for example Figure 3 is a common frozen soil model11. Figure 4 The dam water seepage frozen soil model 11, Figure 5For the slope frozen soil model 11, the preset position is not fixed for different frozen soil models 11, so it is necessary to adjust the position of the stress device relative to the frozen soil model 11 accordingly to apply the constant load and dynamic load at the preset position of the frozen soil model 11. When the first sleeve 24 is mounted on the first crossbeam 22, the first sleeve 24 is moved horizontally on the first crossbeam 22, and the second sleeve 26 is moved longitudinally on the connecting beam 25 to realize the movement of the bearing plate 28 relative to the frozen soil model 11, so that the bearing plate 28 reaches above the preset position of the frozen soil model 11. When the first sleeve 24 is mounted on the first longitudinal beam 23, the first sleeve 24 is moved longitudinally on the first longitudinal beam 23, and the second sleeve 26 is moved horizontally on the connecting beam 25 to realize the movement of the bearing plate 28 relative to the frozen soil model 11, so that the bearing plate 28 reaches above the preset position of the frozen soil model 11. Then, the telescopic device 27 is extended to provide stress to the load-bearing plate 28 , thereby applying a constant load and a dynamic load to the frozen soil model 11 .

[0078] In some optional embodiments, the soil constant load in the frozen soil structure provides a constant load force, and the traffic dynamic load provides a dynamic load force. The constant load force is always present, while the dynamic load force is intermittent. Therefore, the constant load force provided by the telescopic device 27 to the bearing plate 28 can be always present, while the dynamic load force is intermittent. For example, if the constant load force is 10000N and the dynamic load force is 1000N, then in the case of the dynamic load force, the sum of the constant load force and the dynamic load force provided by the telescopic device 27 to the bearing plate 28 is 11000N. In the case of the absence of the dynamic load force, the constant load force provided by the telescopic device 27 to the bearing plate 28 is 10000N, wherein the constant load force is continuously present, and the dynamic load force is intermittently provided by the telescopic device 27.

[0079] In some optional embodiments, the load-bearing columns 21 , the first cross beam 22 , the first longitudinal beam 23 , and the connecting beam 25 may all be made of relatively high-strength steel materials to bear the reaction forces of the constant load and dynamic load applied to the frozen soil model 11 .

[0080] In some embodiments, the frozen soil box 1 includes: a support frame 12, which forms the outline of the box; a bottom plate, which is arranged on the bottom surface of the support frame 12; and a transparent window 13, which is arranged on the side of the support frame 12 and is used to provide a collection window for the optical measurement data collection equipment.

[0081] In some exemplary embodiments, the support frame 12 and the bottom plate can also be made of high-strength steel. One of the purposes of the embodiments of the present application is to study the evolution of the frozen soil structure under the load state of the constant load and the dynamic load. The support frame 12 and the bottom plate provide overall strength support for the frozen soil box 1 to prevent the two from being deformed or damaged under the action of the constant load and the dynamic load, thereby affecting the evolution of the frozen soil model 11.

[0082] In addition, the purpose of the embodiment of the present application is to visually observe or image the evolution process of frozen soil, and further use the evolution image to cooperate with the internal parameters and surface deformation parameters to determine the evolution process of the frozen soil model 11. In the present application, transparent soil is used as the material of the frozen soil model 11. In addition to being able to observe the surface deformation image of the frozen soil model 11, its transparent characteristics can also be used to observe the internal deformation image of the frozen soil model 11. The transparent window 13 is set on the side of the support frame 12 to facilitate the image acquisition device 3 to collect the evolution image. In some exemplary embodiments, the material of the transparent window 13 can be tempered glass, which not only meets the needs of evolution image acquisition, but also provides strength support for the frozen soil box 1.

[0083] In some embodiments, a thermal insulation cover 14 is provided on the top of the support frame 12 to isolate the interior of the frozen soil box 1 from the outside temperature. An opening 15 corresponding to a preset position and adapted to the telescopic device 27 is provided through the thermal insulation cover 14 .

[0084] In this embodiment, the stress device is adjusted so that the bearing plate 28 applies constant load and dynamic load to the frozen soil model 11 corresponding to the preset position of the frozen soil model 11, and then an opening 15 is made according to the specific position of the telescopic device 27, and then it is set on the top of the support frame 12. The relative temperature inside the frozen soil box 1 is isolated from the outside by the thermal insulation top cover 14, so as to avoid the influence of the outside temperature on the frozen soil model 11 during the evolution process.

[0085] In some optional embodiments, the insulation top cover 14 can be a plate-shaped or cloth-shaped material, such as polyvinyl alcohol, polyester and other low-cost polymer insulation materials with good insulation performance. The specific bayonet or splicing scheme of the insulation top cover 14 is determined according to the requirements (i.e. the specific position of the top telescopic device 27), and this application does not make specific limitations here.

[0086] It should be noted that Figure 4 In the exemplary display, it is only to show the relative position relationship between the frozen soil box body 1 and the insulation top cover 14. The gap between the insulation top cover 14 and the frozen soil box body 1 shown therein does not exist in reality. Similarly, Figure 5 , Figure 6 The gap between the intermediate temperature-insulating top cover 14 and the frozen soil box body 1 does not actually exist.

[0087] In some embodiments, the external parameter acquisition device includes: a plurality of profile imaging devices 41 and a plurality of surface displacement measuring devices 42. The plurality of profile imaging devices 41 are arranged on the slope side of the frozen soil model 11 and connected to the image acquisition device 3 to acquire profile imaging of the frozen soil model 11.

[0088] The plurality of surface displacement measuring devices include a fixed end 43 and a telescopic end 44 telescopically connected to the fixed end 43 . The fixed end 43 is fixed in the frozen soil box 1 , and the end of the telescopic end 44 away from the fixed end 43 abuts against different slope sides of the frozen soil model 11 .

[0089] In some exemplary embodiments, the profile imaging device 41 may be a laser, which is used to image the profile of the frozen soil model 11, and the imaging result is transmitted to the image acquisition device 3, so as to further facilitate the acquisition of the evolution image.

[0090] When the temperature regulating device 16 provides the corresponding temperature and the stress device provides the corresponding constant load and dynamic load, the profile imaging device 41 is used to collect the profile imaging of the frozen soil model 11 during the evolution process, and the telescopic end 44 of the surface displacement measuring device is used at different slope sides to determine the surface displacement of different slope sides. For example, if the slope side sinks, the telescopic end 44 extends outward, and if the slope side bulges, the telescopic end 44 retracts inward. The surface displacement measuring device accurately measures the precise displacement data of the surface on different slope sides, realizes the non-invasive measurement of frozen soil deformation, and provides accurate data support for the disasters that may be caused by frozen soil landslides on different slope sides.

[0091] In some optional embodiments, the surface of the telescopic end 44 has scales.

[0092] In some embodiments, reference Figure 3 As shown, the internal parameter acquisition equipment includes: a stress gauge 45, an earth pressure gauge 46, a displacement gauge 47 and a pore water pressure gauge 48. The stress gauge 45, the earth pressure gauge 46 and the displacement gauge 47 are evenly distributed in different structural layers of the frozen soil model 11, and the pore water pressure gauge 48 is set in the pores of the frozen soil model 11;

[0093] The stress gauge 45 is used to measure the constant load and dynamic load carried by the frozen soil model 11;

[0094] The soil pressure gauge 46 is used to measure the change of single-point pressure intensity of different structural layers in the frozen soil model 11 during its evolution;

[0095] The displacement meter 47 is used to measure the single-point displacement of different structural layers in the frozen soil model 11 during its evolution;

[0096] The pore water pressure gauge 48 is used to measure the change of pore water pressure of the frozen soil model 11 during its evolution.

[0097] In this embodiment, the soil pressure gauge 46 is used to determine the specific data of the pressure change at different positions of different structural layers of the frozen soil model 11 during the evolution process, the displacement meter 47 is used to determine the internal displacement data at different positions of different structural layers of the frozen soil model 11 during the evolution process, and the pore water pressure gauge 48 is used to determine the pore water pressure change after the pores originally filled with ice melt into water during the evolution process of the frozen soil model 11, and further determine the pore evolution process. Accordingly, the stress gauge 45 is used to determine the pressure intensity change, single point displacement and pore water pressure change at different positions of different layered structures of the frozen soil model 11 under different constant loads and dynamic loads, thereby providing corresponding data reference for the landslide disaster of the frozen soil structure. Under the condition of a certain temperature, under what constant load and dynamic load, the frozen soil structure will produce corresponding evolution, thereby determining the possible disaster.

[0098] It is understandable that the soil pressure gauge 46, displacement gauge 47 and pore water pressure gauge 48 all realize single-point measurement, that is, the pressure intensity change, internal displacement change and pore water pressure change at the location of the soil pressure gauge 46, displacement gauge 47 and pore water pressure gauge 48. In order to determine whether the single-point pressure intensity change and internal displacement change of the frozen soil model 11 accurately feedback the overall internal displacement change and pressure intensity change of the frozen soil model 11, the embodiment of the present application uses a distributed acquisition element 49 to collect displacement and pressure data for each layer of the structure.

[0099] In some embodiments, the internal parameter acquisition device also includes: a distributed acquisition element 49; a distributed acquisition element 49 is provided in each layer of the structural stratification of the frozen soil model 11, and the extension direction of the distributed acquisition element 49 is the same as the extension direction of each layer in the structural stratification of the frozen soil model 11; the distributed acquisition element 49 is used to collect the overall displacement data and pressure intensity changes of each layer in the structural stratification of the frozen soil model 11.

[0100] Distributed data acquisition elements 49 are set in each layer of the structural layering of the frozen soil model 11, which is equivalent to using distributed elements to measure the overall displacement data and overall pressure intensity changes of the structural layering, and using the overall displacement data and overall pressure intensity changes to compare with single-point displacement data and single-point pressure intensity changes, so that the frozen soil model 11 can be mutually verified during the evolution process, and the results obtained are more accurate, avoiding errors caused by the failure of the single-point displacement data and single-point pressure intensity changes to reflect the overall situation, and avoiding the situation where the data collected for the overall displacement data and overall pressure intensity changes are not accurate enough.

[0101] In some exemplary embodiments, the distributed collection element 49 may be an optical fiber, a TDR cable, or a flexible piezoelectric cable, etc., as long as it can realize the collection of internal displacement data and pressure intensity changes, and is not specifically limited here.

[0102] It should be noted that Figure 3 Only some examples of stress gauges 45, earth pressure gauges 46, displacement gauges 47, pore water pressure gauges 48 and distributed collection elements 49 are shown, and it is not a diagram of the actual distribution of stress gauges 45, earth pressure gauges 46, displacement gauges 47, pore water pressure gauges 48 and distributed collection elements 49 in the embodiment of the present application.

[0103] In some embodiments, reference Figure 4 and Figure 5 As shown, the frozen soil layer evolution test device under static and dynamic loading of the embodiment of the present application can not only perform common frozen soil model tests, but also perform frozen soil structure dam water seepage and frozen soil slope solid water melting seepage tests. According to the type of frozen soil structure in different scenarios, the corresponding frozen soil model can be determined, wherein the missing particles 61 can be arranged in the frozen soil model according to the test requirements. For example, in the frozen soil structure dam water seepage test, the frozen soil model is set in the first area of ​​the frozen soil box 1, and the tracer particles 61 are arranged in the frozen soil model. In the second area, the seepage water body 62 is set on any slope side of the frozen soil model, and the evolution process of the frozen soil model is specifically analyzed in combination with the evolution image collected by the image acquisition device.

[0104] Based on the same inventive concept, Figure 6 As shown, the embodiment of the present application provides a frozen soil layer evolution test method under static and dynamic loading, which is applicable to the frozen soil layer evolution test device under static and dynamic loading in any of the above embodiments, and the method includes:

[0105] S10, using a temperature regulating device to simulate changes in ambient temperature;

[0106] S20, applying a constant load and a dynamic load to a preset position of the frozen soil model using a stress device;

[0107] S30, using an image acquisition device to acquire evolution images of the frozen soil model under the action of a constant load and a dynamic load;

[0108] S40. Utilize parameter acquisition equipment to acquire internal parameters and surface deformation parameters of different structural layers of the frozen soil model.

[0109] In this embodiment, under the premise that the temperature regulating device simulates the ambient temperature, a constant load force simulating the constant load of the soil and a dynamic load force simulating the dynamic load of traffic are applied to the frozen soil model, and an image acquisition device is used to collect the evolution image of the frozen soil model under the action of the constant load force and the dynamic load force, wherein the evolution image includes a surface deformation image and an internal deformation image. Finally, the displacement data and pressure intensity changes inside the frozen soil model are collected by a parameter acquisition device, so as to determine the corresponding internal deformation and displacement and pressure intensity changes of the frozen soil model when the external deformation reaches a certain situation. According to the corresponding relationship therein, the situation of frozen soil landslide is determined, so that frozen soil landslide disasters can be predicted in advance.

[0110] In some embodiments, the method further includes summarizing the evolution images of the image acquisition device and the internal parameters and surface deformation parameters of the parameter acquisition device to determine the displacement data and pressure intensity changes of different structural layers of the frozen soil model during the evolution process.

[0111] The evolution images collected by the image acquisition device and the internal parameters and surface deformation parameters collected by the parameter acquisition device are summarized, the internal deformation images and surface deformation images of the frozen soil model are collected from the evolution images, and the internal parameters and surface deformation parameters are collected from the parameter acquisition device. The internal deformation images and internal parameters are used to corroborate each other, and the internal parameters are used to reflect the strength changes caused by the internal deformation. At the same time, the displacement caused by the internal deformation is measured more accurately, and the surface deformation parameters and surface deformation images are used to corroborate each other, and the surface deformation parameters are used to accurately reflect the displacement caused by the surface deformation.

[0112] During the whole process, for the frozen soil model, both the internal deformation and the surface deformation in the evolution image are visualized. The internal parameters and surface deformation parameters not only accurately reflect the specific displacement caused by the internal deformation and surface deformation, but also reflect the strength changes caused by the deformation. The surface deformation parameters reflect the specific displacement caused by the surface deformation. In addition, the impact of the early internal deformation on the surface deformation can be analyzed through summary, and the frozen soil evolution disaster can be effectively prevented.

[0113] It should be noted that the evolution process of the frozen soil model in the present application not only includes the ice-water evolution process, but also can include the water-ice evolution process, to determine the evolution image of the frozen soil model under the freeze-thaw cycle conditions, as well as the internal parameters and surface deformation parameters of the frozen soil model.

[0114] The experimental device and method for the evolution of frozen soil layers under static and dynamic loading provided in the embodiments of the present application use transparent soil materials as the materials of the frozen soil model. In addition to observing the displacement caused by the deformation of the surface of the frozen soil model, the early disease pores and load evolution process inside the frozen soil model are visually observed. In addition to visually observing the evolution of the soil body of the frozen soil model, the seepage of water bodies under low-temperature freezing or freeze-thaw cycle conditions is also visually observed. At the same time, a temperature regulating device is used to simulate the ambient temperature to determine the evolution process of the frozen soil model at the ambient temperature. A stress device is used to simulate the constant load force of the soil constant load and the dynamic load force of the traffic dynamic load, and the pores in the soil model and the disaster evolution chain process of different structural layers during the strain process are determined. Visual observation is performed to prevent frozen soil disasters.

[0115] At the same time, the second area of ​​the frozen soil box is used to provide a deformation space for the frozen soil model, so as to more accurately determine the disaster process and flow direction during the frozen soil disaster.

[0116] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0117] In addition, to simplify the description and discussion, and in order not to make the embodiments of the present application difficult to understand, the known power supply / ground connection with the integrated circuit (IC) chip and other components may or may not be shown in the provided drawings. In addition, the device can be shown in the form of a block diagram to avoid making the embodiments of the present application difficult to understand, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform to be implemented in the embodiments of the present application (that is, these details should be fully within the scope of understanding of those skilled in the art). In the case of elaborating specific details (e.g., circuits) to describe exemplary embodiments of the present application, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details or when these specific details are changed. Therefore, these descriptions should be considered to be illustrative rather than restrictive.

[0118] Although the present application has been described in conjunction with specific embodiments of the present application, many replacements, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may use the embodiments discussed.

[0119] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A frozen soil evolution test device under static and dynamic loading, characterized in that: include: A frozen soil box, comprising a first area and a second area surrounding the first area, wherein the first area is provided with a frozen soil model, the frozen soil model simulates the stratification of the frozen soil structure, the second area is provided with a temperature regulating device for simulating the change of ambient temperature, and the second area provides a deformation space for the frozen soil model; A stress device, arranged above the frozen soil box, for applying a constant load and a dynamic load to a preset position of the frozen soil model; The image acquisition devices include at least two, which are respectively arranged on the slope side of the frozen soil model box, and the observation directions of the at least two image acquisition devices are perpendicular to each other on the horizontal plane, and are used to acquire the evolution image of the frozen soil model; A parameter acquisition device, comprising an internal parameter acquisition device and an external parameter acquisition device, wherein the internal parameter acquisition device is arranged inside the frozen soil model and is used to acquire internal parameters of different structural layers of the frozen soil model, and the external parameter acquisition device is arranged outside the frozen soil model and is used to acquire surface deformation parameters of the frozen soil model; The structural layers of the frozen soil model are all composed of transparent soil.

2. The frozen soil evolution test device under static and dynamic loading according to claim 1 is characterized in that: It also includes a control device, which is connected to the stress device, the temperature adjustment device, the image acquisition device and the parameter acquisition device respectively, and is used to control the stress device and the temperature adjustment device respectively, and to summarize the evolution image of the image acquisition device and the internal parameters and surface deformation parameters of the parameter acquisition device.

3. The frozen soil evolution test device under static and dynamic loading according to claim 1 is characterized in that: The stress device comprises: A vertically arranged load-bearing column, a first cross beam is provided between the tops of the load-bearing columns arranged along the first direction, a first longitudinal beam is provided between the tops of the load-bearing columns arranged along the second direction, a first sliding sleeve is sleeved on the adjacent first cross beams or first longitudinal beams, a connecting beam is provided between the first sliding sleeves, a second sliding sleeve is sleeved on the connecting beam, a telescopic device is provided vertically downwardly on the second sliding sleeve, a load-bearing plate is provided on one end of the telescopic device away from the second sliding sleeve, and a side of the load-bearing plate away from the telescopic device is in contact with the upper surface of the frozen soil model.

4. The frozen soil evolution test device under static and dynamic loading according to claim 3 is characterized in that: The frozen soil box comprises: A support frame, the support frame forming the outline of the box; A bottom plate, arranged on the bottom surface of the supporting frame; A transparent window is arranged on the side of the supporting frame and is used to provide a collection window for the image collection device.

5. The frozen soil evolution test device under static and dynamic loading according to claim 4 is characterized in that: A thermal insulation cover is provided on the top of the support frame to isolate the interior of the frozen soil box from the outside temperature; an opening corresponding to the preset position and adapted to the telescopic device is provided through the thermal insulation cover.

6. The frozen soil evolution test device under static and dynamic loading according to claim 1 is characterized in that: The external parameter acquisition equipment includes: a plurality of profile imaging devices and a plurality of surface displacement measurement devices; A plurality of the profile imaging devices are arranged on the slope side of the frozen soil model and connected to the image acquisition device, and are used to acquire profile imaging of the frozen soil model; The multiple surface displacement measuring devices include a fixed end and a telescopic end telescopically connected to the fixed end, the fixed end is fixed in the frozen soil box, and the end of the telescopic end away from the fixed end abuts against different slope sides of the frozen soil model.

7. The frozen soil evolution test device under static and dynamic loading according to claim 1 is characterized in that: The internal parameter acquisition equipment includes: a stress gauge, an earth pressure gauge, a displacement gauge and a pore water pressure gauge; the stress gauge, the earth pressure gauge and the displacement gauge are evenly distributed in different structural layers of the frozen soil model, and the pore water pressure gauge is arranged in the pores of the frozen soil model; The stress gauge is used to measure the constant load and dynamic load of the frozen soil model; The soil pressure gauge is used to measure the change of single-point pressure intensity of different structural layers in the frozen soil model during its evolution; The displacement meter is used to measure the single-point displacement data of different structural layers in the frozen soil model during its evolution; The pore water pressure meter is used to measure the change of pore water pressure during the evolution of the frozen soil model.

8. The frozen soil evolution test device under static and dynamic loading according to claim 7 is characterized in that: The internal parameter acquisition device further comprises: a distributed acquisition element; The distributed collection element is provided in each layer of the structural layer of the frozen soil model, and the extension direction of the distributed collection element is the same as the extension direction of each layer in the structural layer of the frozen soil model; The distributed acquisition elements are used to collect the overall displacement data and pressure intensity changes of each layer in the structural stratification of the frozen soil model.

9. A method for testing the evolution of frozen soil layers under static and dynamic loading, applicable to the test device for the evolution of frozen soil layers under static and dynamic loading as claimed in any one of claims 1 to 8, characterized in that: include: Using the temperature regulating device to simulate the change of ambient temperature; Using the stress device to apply a constant load and a dynamic load to a preset position of the frozen soil model; Using an image acquisition device to acquire evolution images of the frozen soil model under the action of a constant load and a dynamic load; The internal parameters and surface deformation parameters of different structural layers of the frozen soil model are collected using parameter collection equipment.

10. The method according to claim 9, characterized in that The evolution images of the image acquisition device and the internal parameters and surface deformation parameters of the parameter acquisition device are summarized to determine the displacement and pressure intensity changes of different structural layers of the frozen soil model during the evolution process.

Images