Device and method for measuring shear strength of joint of root-soil complex and slope rock

Abstract

The invention discloses a device and a method for measuring the shear strength of the joint of a root-soil complex and a slope rock, and relates to the technical field of mechanical measurement, the device comprises a planting device and a shear stress measuring device; the planting device comprises an annular enclosure and an implant, the annular enclosure is arranged around the implant, a soil surrounding space is reserved between the inner side face of the annular enclosure and the outer side face of the implant, the implant can be divided into a plurality of measuring single bodies, each measuring single body comprises a planting mold, a root-soil composite and a rock block, and the top face of the rock block can bear the planting mold. The root-soil complex can be formed in the planting mold, and the bottom of the root-soil complex is in contact with the top surface of the rock block; the shear stress measuring device comprises a first blocking piece, a loading device and a force measuring device, the first blocking piece can abut against the side face of the rock block, the loading device can apply acting force to the planting mold, and the force measuring device can detect the numerical value of the acting force; the method can effectively improve the accuracy of the measurement result.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical measurement, and particularly relates to a device and method for measuring the shear strength at the joint between a root-soil complex and slope rock. Background Art

[0002] In the ecological restoration project of rocky slopes, spraying technologies are one of the most commonly used technologies to achieve slope revegetation and vegetation slope protection. The spraying substrate and vegetation roots form a root-soil complex. The shear stress between the root-soil complex and the rough and fissured contact surface on the slope rock is one of the key indicators characterizing the overall stability of the trinity of vegetation substrate-root-slope.

[0003] At present, relevant research work mainly focuses on the shear strength test of the root-soil complex itself. For spraying ecological restoration projects, in addition to paying attention to the physical and mechanical parameters of the spraying substrate and the root-soil complex itself, it is more necessary to pay attention to the strength parameters between the root-soil complex and the contact surface of the slope rock, especially the shear strength parameters. Since the reasons for the unsatisfactory or failed final restoration effect of spraying ecological restoration technologies are mostly shear slip failures of the root-soil complex along the slope, more attention should be paid to the shear strength parameters between the root-soil complex and the contact surface of the slope rock.

[0004] At present, the methods for measuring the shear strength parameters between the root-soil complex and the contact surface of the slope rock mainly include in-situ testing and laboratory testing. Among them, in laboratory testing, a ring cutter is mostly used to take soil samples and then a shear test is carried out in the laboratory. This method is relatively simple for testing the mechanical parameters of the root-soil complex, but it is impossible to obtain a composite sample in the contact area between the root-soil complex and the slope rock. At the same time, this method causes great disturbance to the sample and cannot obtain accurate test parameters. In-situ testing also has many drawbacks. For example, during the preparation of test sample points, it is easy to disturb the root-soil complex, affecting the accuracy of test results. The test sample points are mostly in different parts of the slope, and it is difficult to install the measuring equipment during testing, which will also affect the accuracy of test results. Summary of the Invention

[0005] The purpose of the present invention is to provide a device and method for measuring the shear strength at the joint between a root-soil complex and slope rock, so as to solve the problems existing in the above-mentioned prior art and effectively improve the accuracy of measurement results.

[0006] To achieve the above purpose, the present invention provides the following solutions: The present invention provides a device for measuring the shear strength at the joint between a root-soil complex and slope rock, comprising a planting device and a shear stress measuring device; the planting device includes an annular enclosure and a planting body, the annular enclosure is arranged around the planting body, a soil-containing space is left between the inner side surface of the annular enclosure and the outer side surface of the planting body, the soil-containing space is used for accommodating planting soil and plants, the planting body can be divided into several measuring monomers, each measuring monomer includes a planting mold, a root-soil complex and a rock block, the top surface of the rock block can bear the planting mold, the root-soil complex can be formed in the planting mold, and the bottom of the root-soil complex contacts the top surface of the rock block; the shear stress measuring device includes a first blocking member, a loading device and a force measuring device, the measuring monomer is used to be placed between the first blocking member and the loading device, the first blocking member can abut against the side surface of the rock block, the loading device can apply a force to the planting mold, the force can cause shear failure at the joint between the bottom of the root-soil complex and the top surface of the rock block, and the force measuring device can detect the value of the force.

[0007] Preferably, the top surface of the rock block is a rough surface, the top surface of the rock block is uneven, several criss-crossing fissures are formed on the top surface of the rock block, the cross-section of the fissure is in a V shape with a wider upper part and a narrower lower part; the depth of the fissure is less than 10 cm; the distance between any two adjacent transverse fissures is less than or equal to 4 cm, and the distance between any two adjacent longitudinal fissures is less than or equal to 4 cm; the width of the fissure is 1 mm to 3 mm, the fissure includes a first fissure and a second fissure, the width of the first fissure is greater than that of the second fissure, the transverse first fissures and the transverse second fissures are alternately and spacedly distributed, and the longitudinal first fissures and the longitudinal second fissures are alternately and spacedly distributed; a separating cushion block is arranged between the planting mold and the rock block.

[0008] Preferably, the outer contour shape of the cross-section of the planting mold is the same as that of the cross-section of the rock block, and the outer contour dimensions of the cross-section of the planting mold are the same as those of the cross-section of the rock block; the planting mold and the rock block are vertically aligned, the gaps between the planting molds are vertically aligned with the gaps between the rock blocks, and the bottom surfaces of all the planting molds are on the same horizontal plane.

[0009] Preferably, the rock block is a cuboid rock block; the number of rows of the measuring monomers is at least five rows, and the number of columns of the measuring monomers is at least five columns.

[0010] Preferably, several rows of through holes are formed on the side wall of the planting mold, several through holes in each row, and any two adjacent upper and lower rows of through holes are staggered from each other.

[0011] Preferably, the distance between any two adjacent through holes in the same row is 2 mm, the diameter of the through hole is 6 mm, and the distance from the lowermost row of through holes to the bottom surface of the planting mold is 3 mm.

[0012] Preferably, it further includes a displacement sensor which can detect the lateral displacement of the planting mold.

[0013] Preferably, the annular enclosure includes four enclosure plates which can form a circle and are detachably and fixedly connected.

[0014] Preferably, the loading device includes a loading plate, a jack, a bracket and a second blocking member. The jack is arranged horizontally. The bracket can support the jack and its height can be adjusted to adjust the height of the jack. The loading plate is used to be placed between the planting mold and the jack, and the second blocking member can block the jack. The jack can apply the acting force to the loading plate and the planting mold.

[0015] The present invention also provides a method for measuring the shear strength at the joint between the root-soil complex and the slope rock. Using the device for measuring the shear strength at the joint between the root-soil complex and the slope rock as described above, it includes the following steps: Step 1: Arrange and combine the rock blocks so that they are in close contact with each other. Step 2: Surround the combined rock blocks with the annular enclosure, and there is a soil ring space between the inner side surface of the annular enclosure and the outer side surface of the combined rock blocks. Step 3: Place each planting mold on each rock block correspondingly. Step 4: The preparation of the planting soil includes determining the ratio of the planting soil and filling the planting soil. The ratio of the planting soil is the same as that of the planting soil used at the engineering site. Fill the planting soil into the space inside the annular enclosure. The filling of the planting soil is divided into base layer filling and surface layer filling. The thickness of the base layer is 10 cm - 12 cm, and the thickness of the surface layer is 2 cm - 3 cm. The base layer filling is layered and tamped, and the thickness of each layer of filling is less than or equal to 5 cm. Step 5: Plant plants in the planting soil in the soil ring space and each planting mold and maintain them to form a root-soil complex in the planting mold. The plants planted are alfalfa, ryegrass or a mixture of alfalfa and ryegrass. Step 6: Cut and separate each measurement monomer to cut off the plant roots between adjacent measurement monomers, and cut and separate the soil ring in the soil ring space and the plant roots in the soil ring from the planting body. Step 7: Remove the annular enclosure. Step 8: Place an unmeasured measurement monomer between the first blocking member and the loading device. Step 9: Apply a uniform force to the planting mold through the loading device until shear failure occurs at the joint between the bottom of the root-soil complex and the top surface of the rock block, and the force measuring device detects the value of the force. Step 10: Calculate the shear stress when shear failure occurs at the joint between the bottom of the root-soil complex and the top surface of the rock block. Step 11: Repeat Steps 8 to 10 until all the measurement units are completed.

[0016] The present invention has achieved the following technical effects compared with the prior art: The shear strength measuring device and method for the joint between the root-soil complex and the slope rock provided by the present invention, by setting the annular enclosure and the soil enclosing space, the soil enclosing space is used to accommodate the planting soil and plants to surround the outer side of the planting body, so as to realize the effective fixation and limitation of the whole planting body. The planting body can be divided into several measurement units, so as to conduct shear tests on different measurement units to obtain multiple groups of shear stress calculation results, improve the accuracy of the measurement results, and in each measurement unit, the planting mold can not only provide a forming space for the formation of the root-soil complex, but also effectively protect the root-soil complex when the planting body is divided into several measurement units, effectively avoiding disturbing the root-soil complex due to the division of the planting body and improving the accuracy of the measurement results. In addition, the soil enclosing space accommodates the planting soil and plants, which can more truly simulate the actual situation of the root-soil complex, improve the degree of the measurement unit approaching the actual situation, and the whole device has a simple structure and is easy to use. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic diagram of the planting device in the shear strength measuring device for the joint between the root-soil complex and the slope rock provided by the present invention; Figure 2 It is Figure 1 a schematic diagram of the measurement unit in Figure 3 It is Figure 2 a schematic diagram of the rock block in Figure 4 It is a schematic diagram of the shear stress measuring device in the shear strength measuring device for the joint between the root-soil complex and the slope rock provided by the present invention; In the figure: 1 - annular enclosure, 2 - soil enclosure space, 3 - measurement unit, 4 - planting mold, 5 - rock block, 6 - first blocking member, 7 - force measuring device, 8 - crack, 9 - through hole, 10 - displacement sensor, 11 - loading plate, 12 - jack, 13 - support, 14 - second blocking member, 15 - horizontal connecting plate, 16 - separating cushion block. Specific implementation manner

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0020] The purpose of the present invention is to provide a device and method for measuring the shear strength at the joint between the root - soil complex and the slope rock, so as to solve the problems existing in the above - mentioned prior art and effectively improve the accuracy of the measurement results.

[0021] To make the above - mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0022] Embodiment 1 As Figures 1 to 4 shown, this embodiment provides a device for measuring the shear strength at the joint between the root - soil complex and the slope rock, including a planting device and a shear stress measuring device; the planting device includes an annular enclosure 1 and a planting body, the annular enclosure 1 is arranged around the planting body, and there is a soil enclosure space 2 between the inner side surface of the annular enclosure 1 and the outer side surface of the planting body. The soil enclosure space 2 is used to accommodate planting soil and plants. The planting body can be divided into several measurement units 3. The measurement unit 3 includes a planting mold 4, a root - soil complex, and a rock block 5. The top surface of the rock block 5 can bear the planting mold 4, the root - soil complex can be formed in the planting mold 4, and the bottom of the root - soil complex is in contact with the top surface of the rock block 5; the shear stress measuring device includes a first blocking member 6, a loading device, and a force measuring device 7. The measurement unit 3 is used to be placed between the first blocking member 6 and the loading device. The first blocking member 6 can abut against the side surface of the rock block 5, the loading device can apply a force to the planting mold 4, the force can cause shear failure at the joint between the bottom of the root - soil complex and the top surface of the rock block 5, and the force measuring device 7 can detect the value of the force.

[0023] The shear strength measuring device for the joint between the root-soil complex and the slope rock provided in this embodiment realizes the effective fixation and limitation of the whole implant by setting the annular enclosure 1 and the soil enclosure space 2, where the soil enclosure space 2 is used to accommodate the planting soil and plants to surround the outer side of the implant. The implant can be divided into several measuring monomers 3, so as to conduct shear tests on different measuring monomers 3 to obtain multiple groups of shear stress calculation results, improving the accuracy of the measurement results. Moreover, in each measuring monomer 3, the planting mold 4 can not only provide a molding space for the formation of the root-soil complex, but also effectively protect the root-soil complex when the implant is divided into several measuring monomers 3, effectively avoiding the disturbance of the root-soil complex caused by the division of the implant and improving the accuracy of the measurement results. In addition, the soil enclosure space 2 accommodates the planting soil and plants, which can more realistically simulate the actual situation of the root-soil complex, improving the degree of approximation of the measuring monomer 3 to the actual situation, and the whole device has a simple structure and is easy to use. As a more preferred implementation manner of this embodiment, the height of the annular enclosure 1 is greater than or equal to the height of the implant to facilitate the full enclosure of the implant. The height of the first blocking member 6 is the same as the height of the rock block 5, and the width of the first blocking member 6 is greater than the width of the rock block 5 to facilitate the full blocking of the rock block 5. As a more preferred implementation manner of this embodiment, the rock block 5 is a rock mass with high strength, not easy to expand when encountering water, not easy to deform, and not easy to dissolve. As a more preferred implementation manner of this embodiment, the material of the planting mold 4 is stainless steel, and the thickness of the planting mold 4 is 2 mm, which is strong and durable.

[0024] The shear stress calculation formula is as follows: In the formula: τ is the shear stress, unit Pa; P is the acting force, unit N; A is the area of the shear surface, unit mm 2 .

[0025] As a relatively preferred embodiment of this embodiment, the top surface of the rock block 5 is a rough surface, the top surface of the rock block 5 is uneven, and a number of criss-crossing fissures 8 are formed on the top surface of the rock block 5. The cross-section of the fissure 8 is a V shape with a wider top and a narrower bottom, and the depth of the fissure 8 is less than 10 cm; the distance between any two adjacent transverse fissures 8 is less than or equal to 4 cm, and the distance between any two adjacent longitudinal fissures 8 is less than or equal to 4 cm; the width of the fissure 8 is 1 mm to 3 mm. The fissure 8 includes a first fissure and a second fissure. The width of the first fissure is greater than the width of the second fissure. The transverse first fissures and the transverse second fissures are alternately distributed at intervals, and the longitudinal first fissures and the longitudinal second fissures are alternately distributed at intervals, which is closer to the surface condition of the real slope rock and can improve the accuracy and authenticity of the measurement results; a separating cushion block 16 is provided between the planting mold 4 and the rock block 5, which can effectively separate the planting mold 4 from the rock block 5 and avoid the adverse interference of the interaction between the planting mold 4 itself and the rock block 5 on the measurement results, and the smoother the separating cushion block 16 is, the better.

[0026] As a relatively preferred embodiment of this embodiment, the top surface of the rock block 5 is made into a rough surface. The manufacturing process is to use artificial or mechanical methods to engrave a number of continuous grooves with undulations on the top surface of the rock block 5; the manufacturing process of the fissure 8 is to use a water jet to cut criss-crossing fissures 8 perpendicular to the top surface of the rock block 5 on the top surface of the rock block 5.

[0027] As a relatively preferred embodiment of this embodiment, the outer contour shape of the cross-section of the planting mold 4 is the same as the outer contour shape of the cross-section of the rock block 5, and the outer contour dimensions of the cross-section of the planting mold 4 are the same as the outer contour dimensions of the cross-section of the rock block 5; the planting mold 4 and the rock block 5 are aligned vertically, the gaps between the planting molds 4 are aligned vertically with the gaps between the rock blocks 5, and the bottom surfaces of all the planting molds 4 are on the same horizontal plane, which is convenient for splitting operations and convenient for use when measuring shear stress.

[0028] As a relatively preferred embodiment of this embodiment, the rock block 5 is a cuboid rock block; the number of rows of the measuring monomers 3 is at least five rows, and the number of columns of the measuring monomers 3 is at least five columns, which can provide a sufficient number of measuring monomers 3, thereby improving the production efficiency of the measuring monomers 3, so as to conduct shear tests on at least twenty-five different measuring monomers 3 and obtain multiple groups of shear stress calculation results, improving the accuracy of the measurement results; when assembling the five-row and five-column rock blocks 5, the processed rock blocks 5 are placed on a flat and hard ground with the top surface facing up, and the placed planar shape is a square.

[0029] As a relatively preferred embodiment of this embodiment, a plurality of rows of through holes 9 are formed in the side wall of the planting mold 4, with several through holes 9 in each row. Any two adjacent rows of through holes 9 up and down are staggered from each other and arranged in a plum blossom shape, so as to facilitate watering and maintenance, and the roots of the plants can also pass through the through holes 9, facilitating the interlaced growth of the roots of the plants in adjacent planting molds 4 between adjacent planting molds 4, and also facilitating the interlaced growth of the roots of the plants in the planting mold 4 and the soil surrounding space 2 between the planting mold 4 and the soil surrounding space 2, so as to more truly restore the actual growth situation of the plant roots and improve the accuracy of the experiment.

[0030] As a relatively preferred embodiment of this embodiment, the distance between any two adjacent through holes 9 in the same row is 2 mm, the diameter of the through hole 9 is 6 mm, and the distance from the lowermost row of through holes 9 to the bottom surface of the planting mold 4 is 3 mm, which improves the water passing capacity of the through holes 9 and effectively prevents the planting soil at the bottom of the planting mold 4 from being washed away.

[0031] As a relatively preferred embodiment of this embodiment, the shear strength measuring device for the root-soil complex and the slope rock joint of this embodiment further includes a displacement sensor 10, and the displacement sensor 10 can detect the lateral displacement of the planting mold 4, so as to timely know the movement situation of the planting mold 4; in this embodiment, the force measuring device 7 uses a pressure sensor, the accuracy of the pressure sensor is less than or equal to 1 N, and the accuracy of the displacement sensor 10 is not less than 0.1 mm.

[0032] As a relatively preferred embodiment of this embodiment, the annular enclosure 1 includes four enclosure plates, and the four enclosure plates can form a circle and are detachably fixedly connected, which is convenient for disassembly and assembly; as a relatively preferred embodiment of this embodiment, the four enclosure plates are all locked and fixed by screws, wing nuts and gaskets made of high-strength stainless steel. Specifically, two wing nuts are provided on each screw, and the wing nuts are threadedly connected to the screw. The four enclosure plates form a square. One end of two parallel enclosure plates is locked and fixed by a screw and two wing nuts, and the other end is also locked and fixed by a screw and two wing nuts. One end of the other two parallel enclosure plates is locked and fixed by a screw and two wing nuts, and the other end is also locked and fixed by a screw and two wing nuts. That is, a total of four screws are arranged around the outside of the planting body (the four screws all pass through the soil surrounding space 2), so a total of four screws, eight wing nuts and eight gaskets need to be provided. The gaskets correspond to the wing nuts one by one, and the gaskets are used to be placed between the wing nuts and the enclosure plates; the enclosure plates are made of wood or steel plates. When using wood, the thickness of the wood is greater than or equal to 3 cm, the length of the enclosure plate is greater than or equal to the length of the overall outer boundary after the combination of each rock block 5, and the height is greater than or equal to the height of the measuring monomer 3.

[0033] As a more preferred embodiment of this embodiment, the loading device includes a loading plate 11, a jack 12, a bracket 13 and a second blocking member 14. The jack 12 is arranged horizontally. The bracket 13 can support the jack 12, and the height of the bracket 13 can be adjusted to adjust the height of the jack 12. The loading plate 11 is used to be placed between the planting mold 4 and the jack 12. The second blocking member 14 can block the jack 12. The jack 12 can apply a force to the loading plate 11 and the planting mold 4. The ejecting part of the jack 12 needs to be aligned with the geometric center of the stress surface of the planting mold 4. The structure is simple and convenient to use. The jack 12 is preferably hydraulically driven. In this embodiment, the height of the second blocking member 14 is equal to the height of the measurement monomer 3, and the width of the second blocking member 14 is equal to the width of the first blocking member 6. In this embodiment, the loading plate 11 is fixedly arranged on the piston head of the jack 12.

[0034] As a more preferred embodiment of this embodiment, the displacement sensor 10 is used to detect the distance that the piston head of the jack 12 extends out to obtain the lateral displacement of the planting mold 4. A pressure sensor is installed between the cylinder block of the jack 12 and the second blocking member 14. By detecting the force that the jack 12 acts on the second blocking member 14 through the pressure sensor, the magnitude of the force that the jack 12 applies to the planting mold 4 can be obtained.

[0035] As a more preferred embodiment of this embodiment, a horizontal connecting plate 15 is connected between the second blocking member 14 and the first blocking member 6. The first blocking member 6 is perpendicular to the horizontal connecting plate 15, and the second blocking member 14 is perpendicular to the horizontal connecting plate 15. The first blocking member 6, the second blocking member 14 and the horizontal connecting plate 15 are all preferably welded by steel plates. The thickness of the steel plate is greater than or equal to 5 mm. The first blocking member 6, the second blocking member 14 and the horizontal connecting plate 15 are welded into one body, and the bottom of the bracket 13 is welded on the horizontal connecting plate 15.

[0036] Embodiment Two This embodiment provides a method for measuring the shear strength at the joint between the root-soil complex and the slope rock. The device for measuring the shear strength at the joint between the root-soil complex and the slope rock in Embodiment One is adopted, including the following steps: Step One: Arrange and combine each rock block 5 so that the rock blocks 5 are in close contact with each other; Step Two: Surround the outside of the combined rock blocks 5 with the annular enclosure 1, and there is a soil-filled space 2 left between the inner side surface of the annular enclosure 1 and the outer side surface of the combined rock blocks 5; Step Three: Place each planting mold 4 corresponding to each rock block 5; Step 4: The preparation of the planting soil includes determining the proportion of the planting soil and filling the planting soil. The proportion of the planting soil is the same as that of the planting soil used at the project site. Fill the space inside the annular enclosure 1 with the planting soil. The filling of the planting soil is divided into base layer filling and surface layer filling. The thickness of the base layer is 10 cm - 12 cm, and the thickness of the surface layer is 2 cm - 3 cm. The base layer filling is carried out in layers and tamped, and the thickness of each filling layer is less than or equal to 5 cm; Step 5: Plant plants in the planting soil in the soil enclosure space 2 and in each planting mold 4, and maintain them to form a root-soil complex in the planting mold 4; The plants planted are alfalfa, ryegrass, or a mixture of alfalfa and ryegrass; Step 6: Cut and separate each measurement monomer 3 to cut off the plant roots between adjacent measurement monomers 3, and cut and separate the soil circle in the soil enclosure space 2 and the plant roots in the soil circle from the implant; Step 7: Remove the annular enclosure 1; Step 8: Place an unmeasured measurement monomer 3 between the first blocking member 6 and the loading device; Step 9: Apply a uniform force to the planting mold 4 through the loading device until shear failure occurs at the joint between the bottom of the root-soil complex and the top surface of the rock block 5, and the force measuring device 7 detects the value of the applied force; Step 10: Calculate the shear stress when shear failure occurs at the joint between the bottom of the root-soil complex and the top surface of the rock block 5; Step 11: Repeat Steps 8 to 10 until all the measurement monomers 3 have been measured.

[0037] The method for measuring the shear strength at the joint between the root-soil complex and the slope rock provided in this embodiment, by setting the annular enclosure 1 and the soil enclosure space 2, the soil enclosure space 2 is used to accommodate the planting soil and plants to surround the outer side of the implant, realizing effective fixation and limitation of the whole implant. The implant can be divided into several measurement monomers 3, so as to conduct shear tests on different measurement monomers 3 to obtain multiple groups of shear stress calculation results, improving the accuracy of the measurement results. And in each measurement monomer 3, the planting mold 4 can not only provide a forming space for the formation of the root-soil complex, but also effectively protect the root-soil complex when the implant is divided into several measurement monomers 3, effectively avoiding disturbing the root-soil complex due to the division of the implant and improving the accuracy of the measurement results. In addition, the soil enclosure space 2 accommodates the planting soil and plants, which can more truly simulate the actual situation of the root-soil complex and improve the degree of approximation of the measurement monomer 3 to the actual situation.

[0038] In the present invention, specific examples are used to illustrate the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A device for measuring the shear strength at the joint between a root-soil complex and slope rock, characterized in that: It includes a planting device and a shear stress measuring device; the planting device includes an annular enclosure and a planting body, the annular enclosure is arranged around the planting body, there is a soil-enclosing space left between the inner side surface of the annular enclosure and the outer side surface of the planting body, and the soil-enclosing space is used to accommodate planting soil and plants. The planting body can be divided into several measuring monomers, each measuring monomer includes a planting mold, a root-soil complex, and a rock block. The top surface of the rock block can bear the planting mold, and the root-soil complex can be formed in the planting mold. The bottom of the root-soil complex contacts the top surface of the rock block; the shear stress measuring device includes a first blocking member, a loading device, and a force measuring device. The measuring monomer is used to be placed between the first blocking member and the loading device. The first blocking member can abut against the side surface of the rock block, the loading device can apply a force to the planting mold, and the force can cause shear failure at the joint between the bottom of the root-soil complex and the top surface of the rock block. The force measuring device can detect the value of the force.

2. The shear strength measuring device for the joint of the root-soil complex and the slope rock according to claim 1, wherein: The top surface of the rock block is a rough surface, the top surface of the rock block is uneven, and there are several criss-crossing fissures on the top surface of the rock block. The cross-section of the fissure is a V shape with a wider top and a narrower bottom; the depth of the fissure is less than 10 cm; the distance between any two adjacent transverse fissures is less than or equal to 4 cm, and the distance between any two adjacent longitudinal fissures is less than or equal to 4 cm; the width of the fissure is 1 mm to 3 mm. The fissure includes a first fissure and a second fissure. The width of the first fissure is greater than the width of the second fissure. The transverse first fissures and the transverse second fissures are alternately and spacedly distributed, and the longitudinal first fissures and the longitudinal second fissures are alternately and spacedly distributed; a separation cushion block is provided between the planting mold and the rock block.

3. The shear strength measuring device for the joint between the root-soil complex and the slope rock according to claim 1, characterized in that: The outer contour shape of the cross-section of the planting mold is the same as the outer contour shape of the cross-section of the rock block, and the outer contour size of the cross-section of the planting mold is the same as the outer contour size of the cross-section of the rock block; the planting mold and the rock block are vertically aligned, the gaps between the planting molds are vertically aligned with the gaps between the rock blocks, and the bottom surfaces of all the planting molds are on the same horizontal plane.

4. The shear strength measuring device at the joint between the root-soil complex and the slope rock according to claim 1, characterized in that: The rock block is a cuboid rock block; the number of rows of the measuring monomers is at least five rows, and the number of columns of the measuring monomers is at least five columns.

5. The shear strength measuring device at the joint between the root-soil complex and the slope rock according to claim 1, wherein: Several rows of through holes are opened on the side wall of the planting mold, and there are several through holes in each row. Any two adjacent rows of the through holes are staggered from each other vertically.

6. The shear strength measuring device for the joint between the root-soil complex and the slope rock according to claim 5, characterized in that: The distance between any two adjacent through holes in the same row is 2 mm, the diameter of the through hole is 6 mm, and the distance from the lowermost row of through holes to the bottom surface of the planting mold is 3 mm.

7. The shear strength measuring device for the joint between the root-soil complex and the slope rock according to claim 1, characterized in that: It further includes a displacement sensor, and the displacement sensor can detect the lateral displacement of the planting mold.

8. The shear strength measuring device at the joint of the root-soil complex and the slope rock according to claim 1, characterized in that: The annular enclosure includes four enclosing plates, and the four enclosing plates can form a circle and are detachably and fixedly connected.

9. The shear strength measuring device at the joint between the root-soil complex and the slope rock according to claim 1, wherein: The loading device includes a loading plate, a jack, a bracket, and a second stopper. The jack is horizontally arranged. The bracket can support the jack, and the height of the bracket can be adjusted to adjust the height of the jack. The loading plate is used to be placed between the planting mold and the jack. The second stopper can block the jack. The jack can apply the acting force to the loading plate and the planting mold.

10. A method for measuring the shear strength at the joint between the root-soil complex and the slope rock, which uses the device for measuring the shear strength at the joint between the root-soil complex and the slope rock as described in any one of claims 1 to 9, and is characterized in that: It includes the following steps: Step 1: Arrange and combine each rock block so that the rock blocks are in close contact with each other. Step 2: Surround the combined rock blocks with an annular enclosure, and there is a soil space left between the inner side surface of the annular enclosure and the outer side surface of the combined rock blocks. Step 3: Place each planting mold corresponding to each rock block. Step 4: The preparation of the planting soil includes determining the proportion of the planting soil and the filling of the planting soil. The proportion of the planting soil is the same as that of the planting soil used at the engineering site. Fill the planting soil into the space inside the annular enclosure. The filling of the planting soil is divided into base layer filling and surface layer filling. The thickness of the base layer is 10 cm to 12 cm, and the thickness of the surface layer is 2 cm to 3 cm. The base layer filling is layered and tamped, and the thickness of each layer of filling is less than or equal to 5 cm. Step 5: Plant plants in the planting soil in the soil space and each planting mold and maintain them to form a root-soil complex in the planting mold. The plants planted are alfalfa, ryegrass, or a mixture of alfalfa and ryegrass. Step 6: Cut and separate each measurement monomer to cut off the plant roots between adjacent measurement monomers, and cut and separate the soil circle and the plant roots in the soil circle in the soil space from the implant. Step 7: Remove the annular enclosure. Step 8: Place an unmeasured measurement monomer between the first stopper and the loading device. Step 9: Apply a uniform acting force to the planting mold through the loading device until shear failure occurs at the joint between the bottom of the root-soil complex and the top surface of the rock block, and the force measuring device detects the value of the acting force. Step 10: Calculate the shear stress when shear failure occurs at the joint between the bottom of the root-soil complex and the top surface of the rock block. Step 11: Repeat steps 8 to 10 until all measurement monomers have been measured.

Images