Snow shear test device and test method with multi-factor coupling

Abstract

The present invention discloses a snow shear test device and test method with multi-factor coupling. The snow shear test device includes a loading module and a shear module. The loading module is located above the shear module and is used to apply a load to the shear module. The shear module includes a shear frame and a first telescopic mechanism arranged at one end of the shear frame. A multi-layer free frame is arranged in the shear frame, and a snow sample is arranged in the multi-layer free frame. A tilting mechanism is arranged under the shear frame. The loading module includes a loading frame, which is arranged above the shear frame and the first telescopic mechanism. The loading frame is used to accommodate a loaded heavy object, and a pressure plate is arranged on the side of the loading frame facing the snow sample. The loading frame and the shear frame are kept at the same tilt angle, so that the downward component of the gravity of the shear module and the loading module are in the same direction, providing a stable shear force for the shearing process of the snow sample and ensuring the accuracy and reliability of the test.

Description

Technical Field

[0001] The invention relates to the technical field of avalanche disaster testing, and in particular to a snow shear testing device and a testing method with multi-factor coupling. Background Art

[0002] Similar to landslides and debris flows, avalanches are a type of surface flow driven by gravity and are one of the most violent land surface activities in the cryosphere. When an avalanche occurs, it carries a large amount of ice, snow, sand, rocks and vegetation down the mountain, creating a powerful destructive force, often causing damage to mountain infrastructure and casualties of people and animals, seriously threatening the safety of residential communities, pastoral areas, tourist areas, mining areas and key infrastructure.

[0003] Snow is the material basis of avalanches, and the shear strength of the snow layer will directly affect the stability of snow on the hillside. The shear strength of the snow layer is affected by the physical characteristics of the snow layer, such as the slope, depth, density, crystal type, and moisture content of the snow layer. Therefore, it is particularly necessary to analyze factors such as the slope, depth, density, crystal type, and moisture content of the snow layer in order to explore the shear deformation and failure laws of the snow layer. It can also provide an important scientific basis for establishing an avalanche prediction and early warning method with clear physical significance and high reliability.

[0004] Large-scale direct shear tests in the field can be used for prediction, but this method has problems such as difficult loading operation, long test cycle and large investment; traditional indoor direct shear instruments have no effective control over the temperature and tilt angle during shearing, resulting in test results that are inconsistent with reality, affecting the accuracy of the prediction results, and unable to meet the current needs for stability assessment of avalanche disasters. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] In view of this, the present invention provides a snow shear test device and test method with multi-factor coupling, wherein the snow shear test device fixes the loading frame above the shear frame, and changes the angle of the tilting mechanism to make the loading frame and the shear frame maintain the same tilt angle, so that the downward sliding component of the gravity of the shear module and the loading module are in the same direction, providing a stable shear force for the shearing process of the snow sample, thereby ensuring the accuracy and reliability of the test.

[0007] Specifically, the following technical solutions are included:

[0008] The embodiment of the first aspect of the present invention provides a snow shear test device with multi-factor coupling, wherein the special-shaped battery of the snow shear test device comprises a loading module and a shear module, wherein the loading module is located above the shear module, and the loading module is used to apply a load to the shear module;

[0009] The shearing module comprises a shearing frame and a first telescopic mechanism arranged at one end of the shearing frame, a multi-layer free frame is arranged inside the shearing frame, a snow sample is arranged inside the multi-layer free frame, and a tilting mechanism is arranged under the shearing frame;

[0010] The loading module comprises a loading frame, which is arranged above the shearing frame and the first telescopic mechanism. The loading frame is used to accommodate a loaded weight. A pressure plate is provided on a side of the loading frame facing the snow sample.

[0011] Optionally, the loading module and the shearing module are arranged in the container, a second pressure sensor is provided at the junction of the multi-layer free frame and the shearing frame, and a first pressure sensor is provided on the side of the pressure plate facing the snow sample.

[0012] Optionally, the tilting mechanism comprises:

[0013] A fixed support, disposed below the shear frame, the fixed support is located on a side opposite to the first telescopic mechanism, and the fixed support is hinged to the shear frame;

[0014] A lifting support is arranged below the shearing frame, the lifting support is located on the same side as the first telescopic mechanism, and the lifting support is hinged to the shearing frame.

[0015] Optionally, the snow shear test device further comprises a tilt compensation mechanism, which is arranged between the shear frame and the multi-layer free frame, and the tilt compensation mechanism is used to adjust the tilt angle of the multi-layer free frame.

[0016] Optionally, the loading framework includes:

[0017] A bearing plate is fixedly arranged above the shear frame and the first telescopic mechanism, a receiving cavity is arranged below the bearing plate, the pressure plate is arranged in the receiving cavity, a ball bearing is arranged between the pressure plate and the receiving cavity, and a directional support is arranged on the side of the bearing plate;

[0018] A rotating baffle is hinged to one end of the bearing plate, the rotating baffle is located at one end of the bearing plate away from the first telescopic mechanism, a sliding rail is provided on the side of the rotating baffle, a sliding support is provided in the sliding rail, and the sliding support is provided on the same side as the directional support;

[0019] A support arm, one end of which is hinged to the sliding support, and the other end of which is hinged to the directional support, and the multiple layers of loaded weights are located between the bearing plate and the rotating baffle.

[0020] Optionally, the snow shear test device further comprises: a displacement meter fixedly connected to the shear frame, the detection head of the displacement meter being arranged toward the multi-layer free frame and located at the height of the shear surface, and the displacement meter being arranged on the same side as the first telescopic mechanism.

[0021] Optionally, the snow shear test device also includes a temperature control box, which is connected to the multi-layer free frame through a refrigerant liquid input pipe and a refrigerant liquid return pipe, and the refrigerant liquid input pipe and the refrigerant liquid return pipe are connected to each other at one end away from the cold liquid. Cold liquid is provided in the temperature control box, and a refrigerant pipe is provided in the cold liquid. The temperature control box is used to control the temperature of the snow sample in the multi-layer free frame, and a plurality of temperature sensors are arranged on the snow sample.

[0022] Optionally, the snow shear test device further includes a receiving control terminal, which is communicatively connected to the first pressure sensor, the second pressure sensor, the displacement meter and the temperature sensor respectively.

[0023] Optionally, the multi-layer free frame comprises: a multi-layer rectangular frame stacked and arranged, wherein the rectangular frame comprises a frame body and flanges arranged on both sides of the frame body, and strip bolt holes are arranged on the flanges.

[0024] The embodiment of the second aspect of the present invention provides a snow shear test method with multi-factor coupling, which is obtained by using the above-mentioned snow shear test device. The snow shear test method includes the following steps:

[0025] Making a snow sample, and placing the snow sample into a multi-layer free frame;

[0026] The temperature is adjusted to a set temperature through a temperature control box, and the temperature of the multi-layer free frame is adjusted until the snow sample in the multi-layer free frame reaches a designed negative temperature;

[0027] The pressure plate is pressed on the snow sample, and a loading weight is placed in the loading frame, so that the overlying load on the top of the snow sample recorded by the first sensor reaches the expected value of the test;

[0028] Open the constraint of one layer of the multi-layer free frame on the shear plane, and keep the other layers fixed;

[0029] The shear frame is gradually raised from a horizontal position until the upper multi-layer free frame starts to slide, and the displacement value of the displacement meter is observed until the displacement value remains stable.

[0030] The embodiments of the present invention provide a snow shear test device and a test method with multi-factor coupling, wherein the snow shear test device includes a loading module and a shear module, which can simulate the loading and shearing conditions of a snow landslide. The loading module is arranged on the shear module, and the angle of the shear module is changed by a tilting mechanism, so that the loading frame and the shear frame maintain the same tilt angle, ensuring that the downward sliding component of the gravity of the shear module and the loading module are in the same direction, providing a stable shear force for the shearing process of the snow sample, and ensuring the accuracy and reliability of the test; by setting a loading weight, it is used to simulate the change of the overlying load of the original snow layer during the snow season, and can reliably restore the change (deformation) law of the snow after shear failure during the snow season, which can meet the application of overlying loads under different tilt states.

[0031] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 A schematic diagram of a snow shear test device with multi-factor coupling according to an embodiment of the present invention;

[0034] Figure 2 A schematic diagram of the interior of a temperature control box according to an embodiment of the present invention;

[0035] Figure 3 is a schematic diagram of a rectangular frame according to an embodiment of the present invention;

[0036] Figure 4 A schematic diagram of the arrangement of a temperature sensor according to an embodiment of the present invention;

[0037] Figure 5 The present invention is a flowchart of the steps of a snow shear test method based on the coupling of factors according to an embodiment of the present invention.

[0038] in, Figures 1 to 4 The corresponding relationship between the reference numerals and the component names is as follows:

[0039] 100 shearing module, 101 shearing frame, 1011 bottom plate, 1012 first baffle plate, 1013 second baffle plate, 102 first telescopic mechanism, 103 multi-layer free frame, 1031 rectangular frame, 1031a frame body, 1031b flange, 1031c strip bolt hole, 104 first pressure sensor, 105 second pressure sensor, 106 temperature sensor, 107 fixed support, 108 lifting support, 109 tilt compensation Mechanism, 110 displacement meter, 200 loading module, 201 bearing plate, 202 rotating baffle, 203 support arm, 204 loading weight, 205 pressure plate, 206 ball bearing, 207 directional support, 208 slide rail, 209 sliding support, 210 connecting bolt, 300 temperature control box, 301 refrigerant input pipe, 302 refrigerant return pipe, 303 cold liquid, 304 refrigerant pipe, 400 receiving control terminal, 500 snow sample, 600 container. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Before further describing the embodiments of the present invention in detail, the directional terms involved in the embodiments of the present invention, such as "upper part", "lower part" and "side part", do not have the meaning of limiting the protection scope of the present invention.

[0042] To make the technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0043] Figure 1 Schematic diagram of a snow shear test device with multiple coupling factors according to an embodiment of the present invention.

[0044] Example 1

[0045] like Figure 1 As shown, an embodiment of the present invention provides a snow shear test device with multi-factor coupling, wherein the snow shear test device includes a loading module 200 and a shear module 100, wherein the loading module 200 is located above the shear module 100, and the loading module 200 is used to apply a load to the shear module 100;

[0046] The shearing module 100 includes a shearing frame 101 and a first telescopic mechanism 102 disposed at one end of the shearing frame 101. A multi-layer free frame 103 is disposed inside the shearing frame 101. A snow sample 500 is disposed inside the multi-layer free frame 103. A tilting mechanism is disposed below the shearing frame 101.

[0047] The loading module 200 includes a loading frame, which is arranged above the shear frame 101 and the first telescopic mechanism 102 . The loading frame is used to accommodate a loading weight 204 . A pressure plate 205 is provided on one side of the loading frame facing the snow sample 500 .

[0048] Among them, the snow shear test device includes a loading module 200 and a shear module 100, which can simulate the loading and shearing conditions of a snow landslide. By setting the loading module 200 on the shear module 100 and changing the angle of the shear module 100 through a tilting mechanism, the loading frame and the shear frame 101 maintain the same tilting angle, ensuring that the downward component of the gravity of the shear module 100 and the loading module 200 are in the same direction, providing a stable shear force for the shearing process of the snow sample 500, and ensuring the accuracy and reliability of the test; by setting a loading weight 204, it is used to simulate the changes in the overlying load of the original snow layer during the snow season, and can reliably restore the deformation evolution law of the snow shear failure during the snow season, which can meet the application of overlying loads under different tilt states.

[0049] Specifically, the shear frame 101 includes a base plate 1011 and a first baffle plate 1012 and a second baffle plate 1013 arranged at both ends of the base plate 1011. The first baffle plate 1012 and the second baffle plate 1013 are both arranged vertically with the base plate 1011. The first telescopic mechanism 102 is arranged on the end of the second baffle plate 1013 away from the base plate 1011. When the first telescopic mechanism 102 is raised, it drives the loading frame to rise, so as to facilitate the placement of the snow sample 500 into the multi-layer free frame 103. After the snow sample 500 is loaded, the first telescopic mechanism 102 retracts to make the loading frame parallel to the base plate 1011. A layer of rectangular frame 1031 (a layer of the multi-layer free frame 103) is reserved on the snow sample 500 to constrain the pressure plate 205. After the snow sample 500 is placed, the first telescopic mechanism 102 is retracted. The structure 102 is retracted to make the loading frame parallel to the bottom plate 1011 of the shear frame 101, and the angle of the shear frame 101 is changed by the tilting mechanism, while the loading frame always remains parallel to the bottom plate 1011. On the one hand, a certain shear force and positive pressure are provided for the snow sample 500, and on the other hand, the downward component of the gravity of the shear module 100 and the loading module 200 is ensured to be in the same direction, providing a stable shear force for the shearing process of the snow sample 500, thereby ensuring the accuracy and reliability of the test; at the same time, the pressure plate 205 is in contact with the snow sample 500, and loading weights 204 of different weights are placed in the loading frame to simulate the change of the overlying load of the original snow layer during the snow season. This can reliably restore the change law of the shear strength of the snow during the snow season, and can meet the application of overlying loads under different tilt states.

[0050] It should be noted that the bottom layer of the multi-layer free frame 103 is fixedly connected to the bottom plate 1011 and is close to the first support baffle 1012. At the same time, the rectangular frames 1031 of each layer of the multi-layer free frame 103 are fixed by bolts. Such an arrangement will not cause the multi-layer free frame 103 to slide. At the same time, since the loaded weight 204 is inclined along the bottom plate direction of the loading frame, and due to its own inertia, it will not move in the vertical direction ( Figure 1 Therefore, the shear frame 101 only needs to be provided with the first support baffle 1012 and the second support baffle 1013, and does not need to be completely closed. Similarly, the loading module 200 only needs to be provided with the bearing plate 201 and the rotating baffle 202. On the one hand, it reduces the material consumption of the snow shear test device, and on the other hand, it is convenient for observation of the test.

[0051] In a feasible implementation, the loading module 200 and the shearing module 100 are arranged in the container 600, a second pressure sensor 105 is provided at the junction of the multi-layer free frame 103 and the shearing frame 101, and a first pressure sensor 104 is provided on the side of the pressure plate 205 facing the snow sample 500.

[0052] It should be noted that by arranging the loading module 200 and the shearing module 100 in the container 600, the overall storage of the snow shearing test device and the movement before and after the test are facilitated.

[0053] Among them, the first pressure sensor 104 is set on the side of the pressure plate 205 facing the snow sample 500, which is used to monitor the size of the overlying load. According to different needs, different weights of the load weight 204 are added to make it conform to the simulation of various situations in reality, so as to improve the reliability and wide application of the snow shear test device; the second pressure sensor 105 is set between the multi-layer free frame 103 and the first baffle plate 1012. At the same time, the second pressure sensor 105 is also in contact with the tilt compensation mechanism 109 to monitor the size of the shear force, and can measure the size of the shear force of various simulated working conditions, so as to obtain the cause analysis of indirect damage when shear failure occurs later. Furthermore, the second pressure sensor 105 is not directly set on the shear surface to avoid damage to the second pressure sensor 105 when shear failure occurs. Therefore, the second pressure sensor 105 is set at the contact point between the multi-layer free frame 103 and the first baffle plate 1012, which is used as the shear pressure for research.

[0054] In a feasible implementation manner, the tilting mechanism includes:

[0055] A fixed support 107 is disposed below the shear frame 101. The fixed support 107 is located on a side opposite to the first telescopic mechanism 102. The fixed support 107 is hinged to the shear frame 101.

[0056] The lifting support 108 is disposed below the shearing frame 101 . The lifting support 108 is located on the same side as the first telescopic mechanism 102 . The lifting support 108 is hinged to the shearing frame 101 .

[0057] Among them, the fixed support 107 is hinged to the bottom plate of the shear frame 101 and is located on one side of the first support plate 1012. The lifting support 108 is hinged to the bottom plate of the shear frame 101 and is located on one side of the second support plate 1013. The angle of the shear frame 101 can be adjusted by lifting and lowering the lifting support 108. By adjusting the angle of the shear frame 101, a part of the gravity component can act as the shear force. Usually, the component along the bottom plate direction is set as the shear force. That is to say, the size of the shear force can be obtained by the weight of the loaded weight 204 and the tilt angle of the tilt mechanism.

[0058] It should be noted that the lifting support 108 and the first telescopic mechanism 102 can be an electric telescopic cylinder, a hydraulic telescopic cylinder or a pneumatic telescopic cylinder, which is not limited here. The fixed support 107 and the lifting support 108 are fixedly connected to the bottom surface of the container 600 at one end away from the shear frame 101, which can ensure the stability of the shear frame 101 when it rotates.

[0059] Furthermore, a track is provided on one end of the lifting support 108 close to the base plate 1011, and one end of the base plate 1011 away from the fixed support 107 is arranged in the track through a bearing. When the lifting support 108 is lifted, the base plate 1011 and the outer ring of the bearing rotate, and under the action of the mutual resistance force between the base plate 1011 and the lifting support 107, the bearing moves in the track, thereby avoiding interference between the base plate 1011 and the lifting support 108 and affecting the lifting of the lifting support 108. The bearing can move in the track, and can also avoid being pulled upward when the lifting support 108 is lifted, thereby ensuring the working stability of the lifting support 108.

[0060] In a feasible implementation manner, the snow shear test device further includes a tilt compensation mechanism 109 , which is disposed between the shear frame 101 and the multi-layer free frame 103 . The tilt compensation mechanism 109 is used to adjust the tilt angle of the multi-layer free frame 103 .

[0061] It should be noted that in the original state (when the base 1011 is in a horizontal state), the multi-layer free frame 103 is in a regular rectangular state. By adding a triangular prism-shaped tilt compensation mechanism 109 of a specific shape, the multi-layer free frame 103 forms a certain tilt angle, rather than a vertical 90° angle. At the same time, the tilt compensation mechanism 109 can always keep the angle formed by the multi-layer free frame 103 unchanged before the start of the test. That is to say, before the test, even if the bottom plate 1011 begins to tilt at a certain angle, the multi-layer free frame will not move toward the first support baffle 1012 under the action of the tilt compensation mechanism 109, which has the possibility of preventing the multi-layer free frame 103 from sliding toward the first support baffle 1012 after the bottom plate 1011 forms an angle.

[0062] Among them, the lifting support 108 is first retracted to make the bottom plate 1011 of the shear frame 101 parallel to the bottom surface of the container 600, and then the tilt compensation mechanism 109 with the required slope is inserted between the first baffle plate 1012 and the multi-layer free frame 103, so that the projection of the multi-layer free frame 103 on the vertical plane is a parallelogram, thereby forming snow samples 500 with different inclination angles, thereby measuring the shear strength of the snow sample 500 at different inclination angles, setting the shear surface in advance, and removing the bolts of the two-layer rectangular frame 1031 (each layer of the multi-layer free frame 103 is a rectangular frame 1031) where the shear surface is located to form a shear surface. The lowest rectangular frame 1031 on one side of the plate 1011 is fixed to the base plate 1011, so only the multiple rectangular frames 1031 above the shear surface can move together (slide under the action of the gravity component), and the lifting of the lifting support 108 is carried out when the tilt compensation mechanism 109 is not withdrawn. At this time, the multi-layer free frame 103 is supported by the tilt compensation mechanism 109 and will not move toward the first baffle plate 1012; further, the snow sample 500 with different inclination angles of the base plate 1011 is studied in order to facilitate the future study of the shear failure law of snow on snow mountains with different slopes, and provide a basis for avalanche prediction.

[0063] It should be noted that by using the tilt compensation mechanism 109 to support the lower end of the multi-layer free frame 103 and replacing the tilt compensation mechanism 109 with different cross-sectional shapes, the multi-layer free frame 103 can present different inclination angles, thereby completing the change of the inclination angle of the snow sample 500 in the multi-layer free frame 103, which helps to simulate snow in different states and improve the accuracy and reliability of avalanche prediction.

[0064] In a feasible implementation, the loading framework includes:

[0065] The bearing plate 201 is fixedly arranged above the shear frame 101 and the first telescopic mechanism 102. A receiving cavity is arranged below the bearing plate 201. A pressure plate 205 is arranged in the receiving cavity. A ball bearing 206 is arranged between the pressure plate 205 and the receiving cavity. A directional support 207 is arranged on the side of the bearing plate 201.

[0066] The rotating baffle 202 is hinged to one end of the bearing plate 201. The rotating baffle 202 is located at one end of the bearing plate 201 away from the first telescopic mechanism 102. A slide rail 208 is provided on the side of the rotating baffle 202. A sliding support 209 is provided in the slide rail 208. The sliding support 209 is provided on the same side as the directional support 207.

[0067] The support arm 203 has one end hinged to the sliding support 209 , and the other end hinged to the directional support 207 . The multi-layer loading weight 204 is located between the bearing plate 201 and the rotating baffle 202 .

[0068] The rotating baffle 202 is hinged to one end of the carrying plate 201, so that the rotating baffle 202 can rotate on the carrying plate 201, and can clamp the load weight 204. The force acting on the snow sample 500 is obtained through the first pressure sensor 104, and the angle formed by the rotating baffle 202 and the carrying plate 201 is fixed through the support arm 203. Specifically, a directional support 207 is fixed on the carrying plate 201, and one end of the support arm 203 is hinged to the directional support 207. There is a slide rail 208, and a sliding support 209 is arranged inside the slide rail 208. The sliding support 209 can move inside the slide rail 208. A connecting through hole is arranged on the sliding support 209. A connecting bolt 210 passes through the other end of the support arm 203 and the connecting through hole, so that the connecting bolt 210 is inserted into the slide rail 205 and stuck (the outer diameter of the connecting bolt 210 matches the width of the slide rail 208), so that the sliding support 209 is fixed at a required position to meet the angle requirement between the rotating baffle 202 and the supporting plate 201.

[0069] It should be noted that the support plate 201 is fixed above the shear frame 101 so that the support plate 201 and the bottom plate 1011 of the shear frame 101 are always kept parallel, that is, the same inclination angle can be maintained at all times, ensuring that the downward component of the gravity of the shear module 100 and the loading module 200 are in the same direction, providing a stable shear force for the shearing process of the snow sample 500. The stable shear force no longer requires the test personnel to assist in adding shear force (in order to meet actual requirements), so that the test personnel can stand next to the snow shear test device and only observe the process of the snow sample 500 being gradually destroyed (the upper snow sample slides) under the action of the shear force. At the same time, the stable shear force also ensures that the shear force size will not become a variable in the test value, thereby ensuring the accuracy of the test results, thereby improving the accuracy of avalanche analysis under the same conditions.

[0070] Furthermore, a receiving cavity is provided below the bearing plate 201, and a pressure plate 205 is provided in the receiving cavity. A ball 206 is provided between the pressure plate 205 and the receiving cavity, so as to reduce the friction between the pressure plate 205 and the upper structure when the pressure plate 205 moves with the shear module 100 during the test. Specifically, if the ball 206 is not provided, the pressure plate 205 is directly fixed to the bearing plate 201. When the test snow body 500 in the shear module 100 undergoes shear displacement, the pressure plate 205 will move on the uppermost layer of the snow body sample 500. On the one hand, due to the application of the ball 206, the pressure plate 205 will move on the uppermost layer of the snow body sample 500. The change of the force point and the sliding of the upper layer of the snow sample 500 on the shear surface will cause the set shear force to change. On the other hand, the excessive friction will also cause a certain degree of melting damage to the snow sample 500. The setting of the ball 206 realizes the rolling connection between the bearing plate 201 and the pressure plate 205, so that the pressure plate 205 can remain relatively still with the upper layer of the snow sample 500 on the shear surface (when shear slip occurs), and will not cause disturbance to the snow sample 500, thereby ensuring the stability of the shear force application and the stability of the snow sample 500.

[0071] It should be noted that the snow sample 500 is not placed in the rectangular frame 1031 of the top layer (close to the supporting plate 201) of the multi-layer free frame 103, but it serves as a constraint frame for the pressure plate 205 to ensure that when the snow sample 500 undergoes shear deformation, the pressure plate 205 and the shear module 100 remain relatively still, which helps to ensure the stability of the shear force.

[0072] In a feasible embodiment, the snow shear test device also includes: a displacement meter 110, which is fixedly connected to the shear frame 101, and the detection head of the displacement meter 110 is set toward the multi-layer free frame 103 and is located at the height of the shear surface. The displacement meter 110 is set on the same side as the first telescopic mechanism 102.

[0073] It should be noted that the shear surface is usually set. If the multi-layer free frame 103 has 10 layers, the shear surface is set between the fifth and sixth layers, and the bolt constraints between the fifth and sixth rectangular frames 1031 are released. Therefore, the position of the displacement meter 110 is also fixed according to the position of the set shear surface.

[0074] Among them, the displacement meter 110 is fixed on the second supporting baffle 1013, and the detection head of the displacement meter 110 is set toward the multi-layer free frame 103 and aligned with the position of the shear surface. The displacement meter 110 is used to monitor the shear displacement of the shear surface. The shear displacement is a sign to determine whether the shear failure is over. When the data of the displacement meter 110 remains stable, it can be considered that the shear failure has ended.

[0075] Figure 2 A schematic diagram of the interior of a temperature control box according to an embodiment of the present invention; Figure 4FIG. 4 is a schematic diagram of the arrangement of a temperature sensor according to an embodiment of the present invention.

[0076] In a possible implementation, Figure 2 and Figure 4 As shown, the snow shear test device also includes a temperature control box 300, which is connected to the multi-layer free frame 103 through a refrigerant liquid input pipe 301 and a refrigerant liquid return pipe 302. The refrigerant liquid input pipe 301 and the refrigerant liquid return pipe 302 are connected to each other at one end away from the cold liquid 303. The temperature control box 300 is provided with a cold liquid 303, and the cold liquid 303 is provided with a refrigeration pipe 304. The temperature control box 300 is used to control the temperature of the snow sample 500 in the multi-layer free frame 103, and a plurality of temperature sensors 106 are arranged on the snow sample 500.

[0077] Among them, through the setting of the temperature control box 300, the ambient temperature in the shear module 100 can be controlled as needed, and the refrigerant inlet pipe 301 and the refrigerant return pipe 302 are arranged in the multi-layer free frame 103 with reserved holes (each layer of the rectangular frame 301 has a certain wall thickness to realize the drilling of reserved holes, which is convenient for the refrigerant inlet pipe 301 and the refrigerant return pipe 302 to pass through), and are connected to the cold liquid 303 of the temperature control box 300. A refrigeration pipe 304 is provided in the cold liquid 303. The cold liquid 303 can be cooled by setting the state of the temperature control box 300, thereby simulating different ambient temperatures and exploring the shear strength of the snow body under different temperature conditions. Specifically, it is common knowledge in the art to realize the circulation of the refrigerant 303 by means of a pump body and will not be elaborated herein. The refrigerant 303 in this embodiment is a 60% concentration ethylene glycol solution, and the refrigeration tube 304 is a liquid nitrogen cooling tube. The refrigerant 303 is cooled. Specifically, the temperature in the refrigerant input tube 301 and the refrigerant return tube 302 is gradually cooled. For example, the refrigeration tube 304 works to gradually make the temperature of the refrigerant 303 in the temperature control box 300 reach -5°C, -10°C, -15°C, -20°C, ..., to ensure the stability of the snow sample 500 (to avoid melting). At the beginning of the test, when the test temperature needs to be higher than the temperature of the existing snow sample 500, the refrigeration tube 304 is closed, and the refrigerant 303 is gradually heated up under the action of room temperature (temperature transfer) until the temperature reaches the required temperature and the test is started.

[0078] It should be noted that the refrigerant inlet pipe 301 and the refrigerant return pipe 302 are made of PVC hoses, which pass through the container 600 and are connected to the multi-layer free frame 103. The PVC hoses and the container 600 are connected through valves. The connection between the refrigerant inlet pipe 301 and the refrigerant return pipe 302 and the multi-layer free frame 103 should avoid the rectangular frame 1031 of the layer where the shear surface is located, so as to avoid the PVC hoses being damaged during shearing and affecting the control of the temperature in the snow shear test device.

[0079] Furthermore, the temperature sensors 106 are arranged in the snow sample 500. The multi-layer free frame 103 is divided into an upper shear frame and a lower shear frame with the set shear plane as the boundary. Three temperature sensors 106 are arranged in the snow sample 500 of the upper shear frame and the lower shear frame respectively. The three temperature sensors 106 of the upper shear frame are sequentially arranged in the snow sample 500 in the up-and-down direction according to equal thickness. Similarly, the three temperature sensors 106 of the lower shear frame are also sequentially arranged in the snow sample 500 in the up-and-down direction according to equal thickness, as shown in FIG. Figure 4 As shown, it should be noted that the monitoring temperatures of the six temperature sensors 106 may fluctuate slightly, but the fluctuation range is very small, and the average value can be taken as the shear temperature. The temperature of the refrigerant delivered by the temperature control box 300 to the snow sample 500 can be adjusted according to the monitoring temperature of the temperature sensor 106.

[0080] In a feasible implementation manner, the snow shear test device further includes a receiving control terminal 400 , which is communicatively connected to the first pressure sensor 104 , the second pressure sensor 105 , the displacement meter 110 , and the temperature sensor 106 , respectively.

[0081] Among them, the controllers of the first telescopic mechanism 102 and the lifting support 108 are also connected to the receiving control terminal 400 for communication. According to the data received by the receiving control terminal 400 from the first pressure sensor 104, the second pressure sensor 105, the displacement meter 110 and the temperature sensor 106, the power parts (the first telescopic mechanism 102 and the lifting support 108) in the snow shear test device are controlled and adjusted, thereby improving the automation level of the snow shear test device.

[0082] Figure 3 FIG. 4 is a schematic diagram of a rectangular frame according to an embodiment of the present invention.

[0083] In a possible implementation, Figure 3 As shown, the multi-layer free frame 103 includes: a multi-layer rectangular frame 1031 stacked, the rectangular frame 1031 includes a frame body 1031a and flanges 1031b arranged on both sides of the frame body 1031a, and strip bolt holes 1031c are provided on the flanges 1031b.

[0084] Among them, each layer of the multi-layer free frame 103 is a rectangular frame 1031 of the same size, and bolts can be inserted into the strip bolt holes 1031c between two adjacent layers of rectangular frames 1031 for fixing. The bottom layer of rectangular frame 1031 of the multi-layer free frame 103 is fixedly connected to the bottom plate 1011 of the shear frame 101. The multi-layer free frame 103 can be used as a shear box for the snow sample 500, and by adding the tilt compensation mechanism 109, the multi-layer free frame 103 is formed as a hexahedron with a parallelogram cross section, thereby forming snow samples 500 with different inclination angles, thereby measuring the shear strength of the snow sample 500 at different inclination angles. Strip bolt holes 1031c are provided on both sides of the rectangular frame 1031, which can improve the stability of the connection between the two adjacent layers of rectangular frames 1031.

[0085] It should be noted that when the snow sample 500 is sheared, the upper rectangular frame 1031 and the lower rectangular frame 1031 of the set shear surface are fixed respectively to ensure that the snow sample 500 only undergoes shear deformation at the shear surface, and the shear surface is set according to actual needs.

[0086] Furthermore, the material of the multi-layer free frame 103 is steel, which can improve the stability and service life of the multi-layer free frame 103.

[0087] Specifically, by setting the lifting support 108, the angle of the shearing module 100 can be adjusted, and the angle of the loading module 200 changes simultaneously, and the shearing force on the snow sample 500 is formed by the downward force of the gravity of the weight 204 loaded in the loading module 200.

[0088] The multi-factor coupled snow shear test device of the present application can obtain the indoor shear device coupled with multiple factors such as ambient temperature, slope inclination and overlying load to explore the change law of shear strength of snow sample 500 under the influence of various factors, and through the setting of receiving control terminal 400, it can transmit monitoring data in time, and make corresponding control instructions for the temperature control box 300 and power components (first telescopic mechanism 102 and lifting support 108) in the snow shear test device accordingly, so as to improve the automation level of the snow shear test device. The snow shear test device is more in line with the actual avalanche situation and has good researchability. The snow shear test device of the present application is used to study the deformation evolution law of snow shear failure, which has certain guiding significance for actual engineering. At the same time, it can be combined with relevant means (artificial intelligence) to predict the destruction time of avalanches to a certain extent.

[0089] Example 2

[0090] Figure 5 The present invention is a flowchart of the steps of a snow shear test method based on the coupling of factors according to an embodiment of the present invention.

[0091] like Figure 5 As shown, another embodiment of the present invention provides a snow shear test method with multi-factor coupling, using the snow shear test device of embodiment 1, the snow shear test method includes the following steps:

[0092] Step 1, preparing a snow sample and placing the snow sample into a multi-layer free frame;

[0093] Step 2, adjusting the temperature to the set temperature through the temperature control box, and adjusting the temperature of the multi-layer free frame until the snow sample in the multi-layer free frame reaches the designed negative temperature;

[0094] Step 3, the pressure plate is pressed on the snow sample, and a load weight is placed in the loading frame so that the overlying load on the top of the snow sample recorded by the first sensor reaches the expected value of the test;

[0095] Step 4, open the constraint of one layer of the multi-layer free frame on the shear plane, and keep the other layers fixed;

[0096] Step 5: The shear frame is gradually raised from a horizontal position until the upper multi-layer free frame begins to slide, and the displacement value of the displacement meter is observed until the displacement value remains stable.

[0097] Among them, in step 1, a snow sample with set water content and density is pre-configured, and the temperature of the snow sample is maintained at about 0°C, and the temperature sensor is installed at a specified position in the snow sample, so that three temperature sensors are sequentially arranged in the snow sample of the upper shear frame in the up-down direction with equal thickness, and three temperature sensors are sequentially arranged in the snow sample of the lower shear frame in the up-down direction with equal thickness, so that the bottom plate of the shear frame is parallel to the bottom surface of the container, and after changing the inclination angle of the multi-layer free frame by using the tilt compensation mechanism, each layer of the multi-layer free frame is fixed to prevent shear deformation of the snow sample before the test begins, and the loading frame is lifted by the first telescopic mechanism, and the prepared The snow sample is placed in the multi-layer free frame; in step 2, the top layer of the frame is reserved in the multi-layer free frame as a constraint for the pressure plate, and the surface of the snow sample is compacted and flattened according to the design requirements. Then the temperature of the temperature control box is usually adjusted to 20°C, and the temperature of the multi-layer free frame is adjusted through the circulation device composed of the refrigerant liquid input pipe, the refrigerant liquid return pipe and the cold liquid until the snow sample in the multi-layer free frame reaches the required design negative temperature. That is to say, the test snow is set to a negative temperature in advance, which can avoid the melting of the snow sample during the test and affect the accuracy of the test; in step 3, the first telescopic mechanism is retracted to press the pressure plate on the snow sample, and the pressure plate is pressed under the pressure plate. The first pressure sensor obtains the size of the overlying load acting on the top of the snow sample, and a load weight is placed in the loading frame until the value of the first pressure sensor reaches the expected value of the test. The rotating baffle of the loading frame is rotated to clamp the side of the load weight, and the support arm is fixed by connecting bolts; in step 4, the constraint of one layer of the multi-layer free frame on the shear plane is opened, and the other layers remain fixed to ensure that the snow sample only undergoes shear deformation at the set shear plane. Usually, the shear plane is set at about the center layer position of the own frame to make it more in line with the actual situation. As described in Example 1, if the multi-layer free frame has 10 layers, the shear plane is set between the fifth and sixth layers from the top, then the solution Open the bolt constraints between the fifth and sixth rectangular frames; in step 5, the shear frame is gradually changed inclination angle from the horizontal position until the upper multi-layer free frame begins to slide, and the value of the displacement meter is observed. When the value displayed on the displacement meter is stable, the test is ended. Among them, when the shear frame begins to gradually rise, the tilt compensation mechanism is removed. At this time, the tilt angle of the shear frame is gradually increased. In this way, with the increase of the tilt angle and the action of the component force of the loaded weight, the shear surface will slip, that is, the upper shear frame and the snow sample therein begin to move. When the value change fluctuation of the displacement meter is around ±2%, it is considered to be numerically stable, and the test is ended.

[0098] Through the experiment, we can obtain data such as the inclination angle during shear displacement and the magnitude of shear force when shear displacement occurs, which can provide a theoretical basis for avalanche prediction and explore the influence relationship between shear strength and temperature, inclination angle and overlying load. It can provide a theoretical basis and experimental data support for further analysis of the specific impact of these factors on avalanches.

[0099] In the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more than two, unless otherwise clearly defined.

[0100] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The description and examples are to be considered exemplary only.

[0101] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A snow shear test device with multi-factor coupling, characterized in that: The snow shear test device comprises a loading module and a shear module, wherein the loading module is located above the shear module, and the loading module is used to apply a load to the shear module; The shearing module comprises a shearing frame and a first telescopic mechanism arranged at one end of the shearing frame, a multi-layer free frame is arranged inside the shearing frame, a snow sample is arranged inside the multi-layer free frame, and a tilting mechanism is arranged under the shearing frame; The loading module comprises a loading frame, which is arranged above the shearing frame and the first telescopic mechanism, the loading frame is used to accommodate a loaded weight, and a pressure plate is arranged on a side of the loading frame facing the snow sample; The snow shear test device includes a tilt compensation mechanism, which is arranged between the shear frame and the multi-layer free frame. The tilt compensation mechanism is used to adjust the tilt angle of the multi-layer free frame. The tilt compensation mechanism is in the shape of a triangular prism and is inserted between the shear frame and the multi-layer free frame so that the projection of the multi-layer free frame on the vertical plane is a parallelogram, thereby forming the snow samples with different inclination angles.

2. The multi-factor coupling snow shear test device according to claim 1 is characterized in that: The loading module and the shearing module are arranged in a container, a second pressure sensor is arranged at the junction of the multi-layer free frame and the shearing frame, and a first pressure sensor is arranged on the side of the pressure plate facing the snow sample.

3. The multi-factor coupling snow shear test device according to claim 1, characterized in that: The tilting mechanism also includes: A fixed support, disposed below the shear frame, the fixed support is located on a side opposite to the first telescopic mechanism, and the fixed support is hinged to the shear frame; A lifting support is arranged below the shearing frame, the lifting support is located on the same side as the first telescopic mechanism, and the lifting support is hinged to the shearing frame.

4. The multi-factor coupling snow shear test device according to claim 1, characterized in that: The loading framework comprises: A bearing plate is fixedly arranged above the shear frame and the first telescopic mechanism, a receiving cavity is arranged below the bearing plate, the pressure plate is arranged in the receiving cavity, a ball bearing is arranged between the pressure plate and the receiving cavity, and a directional support is arranged on the side of the bearing plate; A rotating baffle is hinged to one end of the bearing plate, the rotating baffle is located at one end of the bearing plate away from the first telescopic mechanism, a sliding rail is provided on the side of the rotating baffle, a sliding support is provided in the sliding rail, and the sliding support is provided on the same side as the directional support; A support arm, one end of which is hinged to the sliding support, and the other end of which is hinged to the directional support, and the multiple layers of loaded weights are located between the bearing plate and the rotating baffle.

5. The multi-factor coupling snow shear test device according to claim 2, characterized in that: The snow shear test device also includes: a displacement meter fixedly connected to the shear frame, a detection head of the displacement meter is arranged toward the multi-layer free frame and located at the height of the shear surface, and the displacement meter is arranged on the same side as the first telescopic mechanism.

6. The multi-factor coupling snow shear test device according to claim 5, characterized in that: The snow shear test device also includes a temperature control box, which is connected to the multi-layer free frame through a refrigerant liquid input pipe and a refrigerant liquid return pipe. The refrigerant liquid input pipe and the refrigerant liquid return pipe are connected to each other at one end away from the cold liquid. Cold liquid is provided in the temperature control box, and a refrigerant pipe is provided in the cold liquid. The temperature control box is used to control the temperature of the snow sample in the multi-layer free frame, and a plurality of temperature sensors are arranged on the snow sample.

7. The multi-factor coupling snow shear test device according to claim 6, characterized in that: The snow shear test device also includes a receiving control terminal, which is communicatively connected with the first pressure sensor, the second pressure sensor, the displacement meter and the temperature sensor respectively.

8. The multi-factor coupling snow shear test device according to claim 1, characterized in that: The multi-layer free frame comprises: a multi-layer rectangular frame which is stacked and arranged, wherein the rectangular frame comprises a frame body and flanges arranged on both sides of the frame body, and strip bolt holes are arranged on the flanges.

9. A snow shear test method with multi-factor coupling, obtained by using the snow shear test device according to any one of claims 1 to 8, characterized in that: The snow shear test method comprises the following steps: Making a snow sample, and placing the snow sample into a multi-layer free frame; The temperature is adjusted to a set temperature through a temperature control box, and the temperature of the multi-layer free frame is adjusted until the snow sample in the multi-layer free frame reaches a designed negative temperature; The pressure plate is pressed on the snow sample, and a loading weight is placed in the loading frame, so that the overlying load on the top of the snow sample recorded by the first sensor reaches the expected value of the test; Open the constraint of one layer of the multi-layer free frame on the shear plane, and keep the other layers fixed; The shear frame is gradually raised from a horizontal position until the upper multi-layer free frame starts to slide, and the displacement value of the displacement meter is observed until the displacement value remains stable.

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