Testing device for measuring side wall frictional resistance of underground granary model

Abstract

The utility model relates to a test device for measuring side wall frictional resistance of an underground granary model, which comprises a model pool and the underground granary model arranged in the model pool, the underground granary model comprises a model cylinder, a soil layer is filled between the outer wall of the model cylinder and the inner wall of the model pool, and a soil pressure box is arranged between the outer wall of the model cylinder and the soil layer. The side wall friction model test device further comprises a buoyancy simulation loading mechanism used for applying upward acting force to the model cylinder, a dynamometer is arranged on a loading path of the buoyancy simulation loading mechanism, and a displacement meter used for detecting displacement of the model cylinder relative to a soil layer is arranged at the upper end of the model cylinder. The utility model provides the testing device for measuring the side wall frictional resistance of the underground granary model, which can be used for researching the influence of the surrounding soil layer on the frictional resistance between the outer side walls of the underground granary.

Description

Technical Field

[0001] The utility model relates to a test device for studying the friction resistance between soil layers and underground granaries and measuring the friction resistance of the side wall of an underground granary model. Background Art

[0002] An underground granary refers to a granary with its main body placed underground, which helps save space. At the same time, it can also effectively utilize ground temperature to ensure the temperature inside the granary during the grain removal process, thereby achieving the purpose of saving energy.

[0003] Compared with traditional above-ground granaries, underground granaries have a more complicated working environment. For example, due to the presence of groundwater, groundwater will generate an upward buoyancy on the underground granary. When designing the underground granary, the weight and volume of the underground granary must be designed to avoid the problem of the granary floating due to the buoyancy of groundwater. However, in the underground environment, the surrounding soil layer of the underground granary is in direct contact with the outer wall of the granary. When the underground granary has a tendency to float, a downward friction force will be generated between the surrounding soil layer and the outer wall of the granary. In the existing technology, underground granaries will face the problem of anti-floating safety. At present, when designing underground granaries, the buoyancy of the underground granary is directly calculated according to the highest defense water level using the Archimedes principle, without taking into account the contribution of the side wall friction of the surrounding soil layer to the anti-floating of the underground granary, which will greatly increase the engineering cost of the underground structure and cause unnecessary waste. Utility Model Content

[0004] The utility model aims to provide a test device for measuring the friction resistance of the side wall of an underground granary model, which can study the influence of the surrounding soil layer on the friction resistance between the outer side walls of the underground granary.

[0005] In order to solve the above technical problems, the technical solution of a test device for measuring the side wall friction resistance of an underground granary model in the utility model is as follows:

[0006] A test device for measuring the side wall friction of an underground granary model comprises a model pool and an underground granary model placed in the model pool, wherein the underground granary model comprises a model cylinder, a soil layer is filled between the outer wall of the model cylinder and the inner wall of the model pool, and a soil pressure box is arranged between the outer wall of the model cylinder and the soil layer. The side wall friction model test device also comprises a buoyancy simulation loading mechanism for applying an upward force to the model cylinder, a dynamometer is arranged on the loading path of the buoyancy simulation loading mechanism, and a displacement meter for detecting the displacement of the model cylinder relative to the soil layer is arranged at the upper end of the model cylinder.

[0007] Furthermore, the model tube has no bottom and no cover.

[0008] Furthermore, a soil-isolating and air-permeable layer is provided at the bottom of the inner cavity of the model tube.

[0009] Furthermore, there are at least two groups of earth pressure boxes, each group of earth pressure boxes is arranged at intervals in the up-down direction, and each group of earth pressure boxes includes a plurality of earth pressure boxes arranged at intervals in the circumferential direction.

[0010] Furthermore, a pool top is provided on the top of the model pool, and a reversing fixed pulley is provided on the pool top. The buoyancy model loading mechanism includes a weight, and a pull rope is connected to the upper end of the weight. The pull rope is connected to the upper end of the model tube after passing through the reversing fixed pulley.

[0011] Furthermore, the reversing fixed pulley includes a first reversing fixed pulley arranged on the upper side of the model cylinder and a second reversing fixed pulley arranged on the upper side of the weight, and the dynamometer is connected in series to the pull rope connected between the first reversing fixed pulley and the model cylinder.

[0012] Furthermore, a plurality of connection holes spaced apart along the circumferential direction are provided at the upper end of the model tube, each connection hole is connected to a connection rope, and the upper ends of the connection ropes converge together and are connected to the pull rope.

[0013] The beneficial effects of the utility model are as follows: in the utility model, the friction force of the soil layer on the model tube only exists between the soil layer and the outer wall of the model tube, the buoyancy simulation loading mechanism applies an upward loading force to the model tube to simulate the buoyancy of the underground granary in the real environment, represented by f, and the loading force is measured by a dynamometer. The displacement meter is used to detect whether there is a relative displacement between the model tube and the soil layer. Before the model tube is displaced, the friction force between the soil layer and the outer wall of the model tube is studied. The soil pressure box measures the positive pressure between the soil layer and the outer wall of the model tube, represented by N, then fM=μN, so that the friction coefficient between the soil layer and the outer wall of the model tube can be calculated, and the soil quality of the soil layer can be changed, so as to determine the influence of the friction force between the soil layer and the outer wall of the model tube on the anti-buoyancy under different soil conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood. In the accompanying drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0015] Figure 1 It is a structural schematic diagram of an embodiment of the utility model;

[0016] Explanation of the reference numerals in the accompanying drawings: 1. pool top; 2. second reversing fixed pulley; 3. pull rope; 4. weight; 5. soil layer; 6. model pool; 7. dynamometer; 8. displacement meter; 9. model cylinder; 10. soil pressure box; 11. first reversing fixed pulley; 12. connecting rope. DETAILED DESCRIPTION

[0017] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. The accompanying drawings provide preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0018] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0019] The utility model provides a test device for measuring the friction resistance of the side wall of an underground granary model. Figure 1 As shown: it includes a model pool 6 and an underground granary model placed in the model pool, the underground granary model includes a model tube 9 arranged vertically, the outer wall of the model tube 9 and the inner wall of the model pool are filled with a soil layer 5 that can be replaced as needed, and the bottom lower side of the model tube 9 also has a corresponding soil layer. In this embodiment, the model tube is bottomless and coverless, that is to say, the model tube is a cylinder with an axis extending in the up-down direction. When filling the soil layer, a bottom soil layer can be laid at the bottom of the model pool first, and then the model tube is placed on the bottom soil layer, and then the soil layer is filled between the outer periphery of the model tube and the inner wall of the model pool to prevent the soil layer from entering the inner side of the model tube and to prevent the friction between the soil layer and the inner wall of the model tube. In other embodiments of the utility model, a soil-isolating and air-permeable layer (for example, a soil-isolating and air-permeable adhesive) can also be provided at the bottom of the model tube to prevent the soil layer from entering the interior of the model tube.

[0020] Earth pressure boxes 10 are arranged between the outer wall of the model tube and the soil layer. In this embodiment, there are at least two groups of earth pressure boxes 10. Each group of earth pressure boxes 10 is arranged at intervals along the up and down directions, and each group of earth pressure boxes includes a plurality of earth pressure boxes arranged at intervals along the circumferential direction.

[0021] The test device also includes a buoyancy simulation loading mechanism for applying an upward force to the model tube, a dynamometer 7 is provided on the loading path of the buoyancy simulation loading mechanism, and a displacement meter 8 for detecting the displacement of the model tube relative to the soil layer is provided at the upper end of the model tube. In this embodiment, there are at least three displacement meters 8, and the plurality of displacement meters are distributed circumferentially at the upper end of the model tube, and each displacement meter is used to measure the displacement between the corresponding point of the model tube and the soil layer. When the model tube is tilted or displaced, the displacement meter can measure and obtain corresponding displacement data.

[0022] The top of the model pool is provided with a pool top 1, and two reversing fixed pulleys are provided on the pool top. The buoyancy model loading mechanism includes a weight, and a pull rope 3 is connected to the upper end of the weight. The pull rope is connected to the upper end of the model tube after winding through the reversing fixed pulley. The two reversing positioning pulleys are respectively a first reversing fixed pulley 11 located on the upper side of the model tube and a second reversing fixed pulley 2 located on the upper side of the weight. The upper end of the model tube is provided with a plurality of connection holes arranged at intervals along the circumferential direction, and each connection hole is connected to a connection rope 12, and the upper ends of each connection rope 12 are gathered together and connected to the pull rope 3.

[0023] A dynamometer 7 is connected in series to the pull rope between the first reversing fixed pulley and the model cylinder. The dynamometer 7 is arranged at this position to directly measure the upward pulling force exerted on the model cylinder, thereby avoiding the influence of the friction between the pull rope and the reversing fixed pulley on the force measurement.

[0024] The side wall friction model test device can measure the friction coefficient between different soil layers and the model tube, so as to explore the influence of side wall friction resistance on anti-floating. In a real underground granary, considering the corresponding soil layer pressure, the friction between the real soil layer and the underground granary can be calculated. When designing the underground granary, taking this friction into account will help reduce the weight design of the underground structure, thereby reducing the engineering cost of the underground structure and reducing unnecessary waste.

[0025] In the above description of this specification, unless otherwise clearly specified and limited, the terms "fixed", "installed", "connected" or "connected" should be understood in a broad sense. For example, with regard to the term "connection", it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. Therefore, unless otherwise clearly defined in this specification, those skilled in the art can understand the specific meanings of the above terms in this utility model according to the specific circumstances.

[0026] According to the above description of this specification, those skilled in the art may also understand that the terms used below, such as "up", "down", "front", "back", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", "center", "longitudinal", "lateral", "clockwise" or "counterclockwise", etc., which indicate the orientation or position relationship, are based on the orientation or position relationship shown in the drawings of this specification, and are only for the purpose of facilitating the explanation of the scheme of the utility model and simplifying the description, rather than explicitly or implicitly indicating that the device or element involved must have the specific orientation, be constructed and operate in a specific orientation. Therefore, the above-mentioned orientation or position relationship terms cannot be understood or interpreted as limitations on the scheme of the utility model.

[0027] In addition, the terms "first" or "second" used in this specification to refer to numbers or ordinals are only used for descriptive purposes and cannot be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this specification, the meaning of "plurality" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A test device for measuring the side wall friction of an underground granary model, characterized in that: The invention comprises a model pool and an underground granary model placed in the model pool, wherein the underground granary model comprises a model cylinder, a soil layer is filled between the outer wall of the model cylinder and the inner wall of the model pool, an earth pressure box is arranged between the outer wall of the model cylinder and the soil layer, and the side wall friction model test device further comprises a buoyancy simulation loading mechanism for applying an upward force to the model cylinder, a dynamometer is arranged on the loading path of the buoyancy simulation loading mechanism, and a displacement meter for detecting the displacement of the model cylinder relative to the soil layer is arranged at the upper end of the model cylinder.

2. The test device according to claim 1, characterized in that: The model cylinder has no bottom and no cover.

3. The test device according to claim 1, characterized in that: A soil-isolating and air-permeable layer is arranged at the bottom of the inner cavity of the model tube.

4. The test device according to claim 1, characterized in that: There are at least two groups of earth pressure boxes, each group of earth pressure boxes is arranged at intervals along the up-down direction, and each group of earth pressure boxes includes a plurality of earth pressure boxes arranged at intervals along the circumferential direction.

5. The test device according to any one of claims 1 to 4, characterized in that: The top of the model pool is provided with a pool top, on which a reversing fixed pulley is provided. The buoyancy model loading mechanism comprises a weight, the upper end of which is connected with a pull rope, which is connected to the upper end of the model tube after passing through the reversing fixed pulley.

6. The test device according to claim 5, characterized in that: The reversing fixed pulley comprises a first reversing fixed pulley arranged on the upper side of the model tube and a second reversing fixed pulley arranged on the upper side of the weight, and the dynamometer is serially connected to the pull rope connected between the first reversing fixed pulley and the model tube.

7. The test device according to claim 5, characterized in that: The upper end of the model tube is provided with a plurality of connection holes which are arranged at intervals along the circumferential direction, each connection hole is connected with a connection rope, and the upper ends of the connection ropes are gathered together and connected with the pull rope.

Images