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

Abstract

The present invention discloses a device and method for measuring the shear strength of a junction between a root-soil complex and a slope rock, relating to the technical field of mechanical measurement, comprising a planting device and a shear stress measuring device; the planting device comprises an annular enclosure and a planting body, the annular enclosure is arranged around the planting body, a soil space is left between the inner side surface of the annular enclosure and the outer side surface of the planting body, the planting body can be divided into a plurality of measuring units, the measuring units comprise a planting mold, a root-soil complex and a rock block, the top surface of the rock block can support 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 comprises a first blocking member, a loading device and a force measuring device, the first blocking member can be against the side surface of the rock block, the loading device can apply a force to the planting mold, and the force measuring device can detect the value of the force; the present invention can effectively improve the accuracy of the measurement results.

Description

Technical Field

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

[0002] In the ecological restoration project of rock slopes, spray seeding technology is one of the most commonly used technologies to achieve slope greening and vegetation slope protection. The spray seeding substrate and the vegetation root system form a root-soil complex. The shear stress between the root-soil complex and the rough, cracked contact surface on the slope rock is one of the key indicators to characterize the overall stability of the vegetation substrate-root system-slope trinity.

[0003] Currently, research focuses primarily on testing the shear strength of the root-soil complex itself. However, for spray-seeding ecological restoration projects, in addition to focusing on the physical and mechanical parameters of the seeding substrate and the root-soil complex itself, greater attention should be paid to the strength parameters of the interface between the root-soil complex and the slope rock, particularly the shear strength parameter. Because unsatisfactory results or failures of spray-seeding ecological restoration techniques are often due to shear slippage along the slope, the shear strength parameter at the interface between the root-soil complex and the slope rock should be given greater attention.

[0004] Currently, there are two main methods for measuring the shear strength parameters of the interface between the root-soil complex and the slope rock: in-situ testing and laboratory testing. Laboratory testing typically involves taking soil samples with a circular cutter and then conducting shear tests in the laboratory. This method is relatively simple for measuring the mechanical parameters of the root-soil complex, but it cannot obtain composite specimens in the contact area between the root-soil complex and the slope rock. Furthermore, this method significantly disturbs the sample, making it difficult to obtain accurate test parameters. In-situ testing also has many drawbacks, such as: The root-soil complex can be easily disturbed during sample preparation, affecting the accuracy of the test results; and test samples are often located in different parts of the slope, making it difficult to install the measuring equipment during testing, which also affects the accuracy of the 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 of the junction between a root-soil complex and slope rocks, so as to solve the problems existing in the above-mentioned prior art and effectively improve the accuracy of the measurement results.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a device for measuring the shear strength of a junction between a root-soil complex and a slope rock, comprising a planting device and a shear stress measuring device; the planting device comprises an annular enclosure and a planting body, the annular enclosure is arranged around the planting body, a soil space is left between the inner side of the annular enclosure and the outer side of the planting body, the soil space is used to accommodate planting soil and plants, the planting body can be divided into a plurality of measuring units, the measuring units comprise a planting mold, a root-soil complex and a rock block, the top surface of the rock block can support 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 comprises a first blocking member, a loading device and a force measuring device, the measuring unit is used to be placed between the first blocking member and the loading device, the first blocking member can be against the side of the rock block, the loading device can apply a force to the planting mold, the force can cause shear failure at the junction of 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.

[0008] Preferably, the top surface of the rock block is a rough surface, the top surface of the rock block is uneven, and a number of criss-cross cracks are opened on the top surface of the rock block, and the cross-section of the cracks is V-shaped, wide at the top and narrow at the bottom; the depth of the cracks is less than 10 cm; the spacing between any two adjacent transverse cracks is less than or equal to 4 cm, and the spacing between any two adjacent longitudinal cracks is less than or equal to 4 cm; the width of the cracks is 1 mm to 3 mm, and the cracks include a first crack and a second crack, the width of the first crack is greater than the width of the second crack, the first transverse cracks and the second transverse cracks are alternately distributed, and the first longitudinal cracks and the second longitudinal cracks are alternately distributed; a separation pad is provided between the planting mold and the rock block.

[0009] Preferably, 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 is aligned up and down with the rock block, the gaps between the planting molds are aligned up and down with the gaps between the rock blocks, and the bottom surfaces of all the planting molds are on the same horizontal plane.

[0010] Preferably, the rock block is a rectangular parallelepiped rock block; the number of rows of the measuring units is at least five, and the number of columns of the measuring units is at least five.

[0011] Preferably, a plurality of rows of through holes are provided on the side wall of the implant mold, with a plurality of through holes in each row, and any two upper and lower adjacent rows of through holes are staggered with each other.

[0012] Preferably, the distance between any two adjacent through holes in the same row is 2 mm, the diameter of the through holes is 6 mm, and the distance from the through holes in the bottom row to the bottom surface of the implant mold is 3 mm.

[0013] Preferably, a displacement sensor is further included, and the displacement sensor can detect the lateral displacement of the implant mold.

[0014] Preferably, the annular enclosure includes four enclosures, the four enclosures can form a circle, and the four enclosures can be detachably fixedly connected.

[0015] 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, 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 blocking member can block the jack; the jack can apply the force to the loading plate and the planting mold.

[0016] The present invention also provides a method for measuring the shear strength of the junction between a root-soil complex and a slope rock, using the above-mentioned device for measuring the shear strength of the junction between a root-soil complex and a slope rock, comprising the following steps:

[0017] Step 1: Arrange the rocks so that they are in close contact with each other;

[0018] Step 2: surround the outer side of the assembled rock block with a circular enclosure, and leave a soil space between the inner side of the circular enclosure and the outer side of the assembled rock block;

[0019] Step 3: Place each planting mold on each rock block one by one;

[0020] Step 4: The preparation of planting soil includes determining the proportion of planting soil and filling of planting soil. The proportion of planting soil is consistent with the proportion of planting soil used on the project site. The planting soil is filled into the space inside the circular enclosure. The filling of planting soil is divided into base filling and surface filling. The thickness of the base layer is 10cm~12cm, and the thickness of the surface layer is 2cm~3cm. The base filling is layered and compacted. The thickness of each layer is less than or equal to 5cm.

[0021] Step 5: Planting plants in the soil in the circle and in each planting mold, and maintaining them to form a root-soil complex in the planting mold; the planted plants are alfalfa, ryegrass, or a mixture of alfalfa and ryegrass;

[0022] Step 6: Cut and separate each measurement unit to cut off the plant root system between adjacent measurement units, and cut and separate the soil circle in the soil circle and the plant root system in the soil circle from the plant body;

[0023] Step 7: Remove the circular enclosure;

[0024] Step 8: Take a measurement unit that has not been measured and place it between the first blocking member and the loading device;

[0025] Step 9: Apply force to the planting mold at a uniform speed through the loading device until shear failure occurs at the junction of 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;

[0026] Step 10: Calculate the shear stress at the junction of the bottom of the root-soil complex and the top surface of the rock block when shear failure occurs;

[0027] Step 11: Repeat steps 8 to 10 until all the test monomers have been tested.

[0028] Compared with the prior art, the present invention has achieved the following technical effects:

[0029] The present invention provides a device and method for measuring the shear strength of the junction of a root-soil complex and slope rocks. By setting an annular enclosure and a soil-enclosed space, the soil-enclosed space is used to accommodate planting soil and plants, so as to surround the outer side of the implant, thereby achieving effective fixation and limitation of the entire implant. The implant can be divided into several measuring units, so as to facilitate shear tests on different measuring units to obtain multiple groups of shear stress calculation results, thereby improving the accuracy of the measurement results. In each measuring unit, the planting mold can not only provide a molding space for the molding of the root-soil complex, but also effectively protect the root-soil complex when the implant is divided into several measuring units, effectively avoiding disturbance of the root-soil complex caused by the division of the implant, thereby improving the accuracy of the measurement results. In addition, the soil-enclosed space accommodates planting soil and plants, which can more realistically simulate the actual situation of the root-soil complex, improve the degree to which the measuring units are close to the actual situation, and the entire device has a simple structure and is easy to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in 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 paying any creative work.

[0031] Figure 1 A schematic diagram of a planting device in a device for measuring the shear strength of the junction between a root-soil complex and slope rocks provided by the present invention;

[0032] Figure 2 for Figure 1 Schematic diagram of the assay monomer in;

[0033] Figure 3 for Figure 2 Schematic diagram of the rock blocks in

[0034] Figure 4 Schematic diagram of a shear stress measuring device in a shear strength measuring device for a joint between a root-soil complex and a slope rock provided by the present invention;

[0035] In the figure: 1-annular enclosure, 2-soil space, 3-measuring 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-bracket, 14-second blocking member, 15-horizontal connecting plate, 16-separation pad. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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 making creative efforts are within the scope of protection of the present invention.

[0037] The purpose of the present invention is to provide a device and method for measuring the shear strength of the junction between a root-soil complex and slope rocks, so as to solve the problems existing in the above-mentioned prior art and effectively improve the accuracy of the measurement results.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Example 1

[0040] like Figures 1 to 4As shown, this embodiment provides a shear strength measuring device for the junction of a root-soil complex and a 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 a soil space 2 is left between the inner side of the annular enclosure 1 and the outer side of the planting body, the soil space 2 is used to accommodate planting soil and plants, and the planting body can be divided into a plurality of measuring units 3, the measuring 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 support 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 measuring unit 3 is used to be placed between the first blocking member 6 and the loading device, the first blocking member 6 can be against the side 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 junction of 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.

[0041] The present embodiment provides a device for measuring the shear strength of the junction between the root-soil complex and the slope rock, which is provided by setting an annular enclosure 1 and a soil-enclosed space 2. The soil-enclosed space 2 is used to accommodate planting soil and plants, so as to surround the outer side of the implant, thereby achieving effective fixation and limitation of the implant as a whole. The implant can be divided into several measuring monomers 3, so as to facilitate shear tests on different measuring monomers 3 to obtain multiple groups of shear stress calculation results, thereby improving the accuracy of the measurement results. In addition, in each measuring monomer 3, the planting mold 4 can not only provide a molding space for the molding 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 disturbance of the root-soil complex caused by the division of the implant, thereby improving the accuracy of the measurement results. In addition, the soil-enclosed space 2 contains planting soil and plants, can more realistically simulate the actual root-soil complex situation, improve the degree to which the measuring unit 3 is close to the actual situation, and the whole device has a simple structure and is easy to use; as a more preferred implementation method of this embodiment, the height of the annular enclosure 1 is greater than or equal to the height of the implant, so as to fully enclose the implant, the height of the first blocking member 6 is consistent with 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, so as to fully block the rock block 5; as a more preferred implementation method of this embodiment, the rock block 5 is a rock block with high strength, which is not easy to expand, deform, or dissolve when exposed to water; as a more preferred implementation method 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.

[0042] The shear stress calculation formula is:

[0043] Where: τ is shear stress, unit: Pa; P is force, unit: N; A is the area of ​​shear surface, unit: mm 2 .

[0044] As a more preferred implementation manner 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-cross cracks 8 are opened on the top surface of the rock block 5. The cross-section of the crack 8 is V-shaped, wide at the top and narrow at the bottom, and the depth of the crack 8 is less than 10 cm; the spacing between any two adjacent transverse cracks 8 is less than or equal to 4 cm, and the spacing between any two adjacent longitudinal cracks 8 is less than or equal to 4 cm; the width of the crack 8 is 1 mm to 3 mm, and the crack 8 includes a first crack and a second crack, the width of the first crack is greater than the width of the second crack, the first transverse crack and the second transverse crack are alternately distributed, and the first longitudinal crack and the second longitudinal crack are alternately distributed, which is closer to the surface condition of the real slope rock and can improve the accuracy and authenticity of the measurement results; a separation pad 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 interaction between the planting mold 4 itself and the rock block 5 causing adverse interference to the measurement results, and the smoother the separation pad 16, the better.

[0045] As a more preferred implementation method of this embodiment, the top surface of the rock block 5 is made into a rough surface. The production process is to use manual or mechanical methods to carve out a number of continuous grooves with undulations on the top surface of the rock block 5; the production process of the cracks 8 is to use a water jet to cut out criss-cross cracks 8 perpendicular to the top surface of the rock block 5 on the top surface of the rock block 5.

[0046] As a more preferred implementation method 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 size of the cross section of the planting mold 4 is the same as the outer contour size of the cross section of the rock block 5; the planting mold 4 is aligned with the rock block 5 up and down, and the gaps between the planting molds 4 are aligned with the gaps between the rock blocks 5 up and down, and the bottom surfaces of all planting molds 4 are on the same horizontal plane, which is convenient for splitting operations and easy to use when measuring shear stress.

[0047] As a more preferred implementation of this embodiment, the rock block 5 is a rectangular rock block; the number of rows of measuring monomers 3 is at least five rows, and the number of columns of 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 facilitate shear tests on at least twenty-five different measuring monomers 3, obtain multiple groups of shear stress calculation results, and improve the accuracy of the measurement results; when assembling the five rows and five columns of rock blocks 5, the processed rock blocks 5 are placed with the top surface facing up on a flat and hard ground, and the plane shape of the placement is a square.

[0048] As a more preferred implementation of this embodiment, several rows of through holes 9 are provided on the side wall of the planting mold 4, with several through holes 9 in each row. Any two adjacent rows of through holes 9 are staggered with each other in a plum blossom shape to facilitate watering and maintenance, and the roots of the plants can also pass through the through holes 9, so that the roots of the plants in adjacent planting molds 4 can grow interlaced and staggered between the adjacent planting molds 4, and the roots of the plants in the planting molds 4 and the enclosed soil space 2 can grow interlaced and staggered between the planting molds 4 and the enclosed soil space 2, so as to more realistically restore the actual growth of the plant roots and improve the accuracy of the test.

[0049] As a more preferred implementation method of this embodiment, the spacing 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 bottom row of through holes 9 to the bottom surface of the planting mold 4 is 3 mm, which improves the water flow capacity of the through holes 9 and effectively avoids washing away the planting soil at the bottom of the planting mold 4.

[0050] As a more preferred implementation method of this embodiment, the shear strength measuring device at the junction of the root-soil complex and the slope rock provided in this embodiment also includes a displacement sensor 10, which can detect the lateral displacement of the planting mold 4 so as to timely know the movement of the planting mold 4; in this embodiment, the force measuring device 7 adopts a pressure sensor, the accuracy of the pressure sensor is less than or equal to 1N, and the accuracy of the displacement sensor 10 is not less than 0.1mm.

[0051] As a more preferred implementation of this embodiment, the annular enclosure 1 includes four enclosures, which can form a circle, and the four enclosures can be detachably fixedly connected, which is convenient for disassembly and assembly; as a more preferred implementation of this embodiment, the four enclosures are all locked and fixed by screws, wing nuts and gaskets made of high-strength stainless steel. Specifically, each screw is provided with two wing nuts, which are threadedly connected to the screws, and the four enclosures form a square, in which one end of two mutually parallel enclosures 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 enclosures are fixed by a screw and two winged nuts, and the other end is also fixed by a screw and two winged nuts, that is, a total of four screws are arranged around the outside of the implant (all four screws pass through the ring soil space 2), so a total of four screws, eight winged nuts and eight gaskets are required. The gaskets correspond to the winged nuts one by one, and the gaskets are used to be placed between the winged nuts and the enclosures; the enclosures are made of wooden boards or steel plates. When wooden boards are used, the thickness of the wooden boards is greater than or equal to 3 cm, the length of the enclosures is greater than or equal to the length of the overall outer boundary of the combined rock blocks 5, and the height is greater than or equal to the height of the measuring unit 3.

[0052] As a more preferred implementation 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, and the second blocking member 14 can block the jack 12; the jack 12 can apply force to the loading plate 11 and the planting mold 4, and the ejection part of the jack 12 needs to be aligned with the geometric center of the force-bearing surface of the planting mold 4. The structure is simple and easy 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 measuring unit 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 fixed on the piston head of the jack 12.

[0053] As a more preferred implementation method of this embodiment, the distance that the piston head of the jack 12 is extended is detected by the displacement sensor 10 to obtain the lateral displacement of the planting mold 4; a pressure sensor is installed between the cylinder body of the jack 12 and the second blocking member 14, and the force applied by the jack 12 on the second blocking member 14 is detected by the pressure sensor to obtain the magnitude of the force applied by the jack 12 to the planting mold 4.

[0054] As a more preferred implementation scheme 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 preferably welded from steel plates, and the thickness of the steel plates 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 as one, and the bottom of the bracket 13 is welded to the horizontal connecting plate 15.

[0055] Example 2

[0056] This embodiment provides a method for measuring the shear strength of the junction between a root-soil complex and a slope rock, using the device for measuring the shear strength of the junction between a root-soil complex and a slope rock in the first embodiment, including the following steps:

[0057] Step 1: Arrange the rocks 5 so that they are in close contact with each other;

[0058] Step 2: surround the outer side of the combined rock block 5 with the annular enclosure 1, and leave a soil space 2 between the inner side of the annular enclosure 1 and the outer side of the combined rock block 5;

[0059] Step 3: Place the planting molds 4 on the rocks 5 one by one;

[0060] Step 4: The preparation of planting soil includes determining the proportion of planting soil and filling of planting soil. The proportion of planting soil is consistent with the proportion of planting soil used on the project site. The planting soil is filled into the space inside the annular enclosure 1. The filling of planting soil is divided into base filling and surface filling. The thickness of the base is 10cm~12cm, and the thickness of the surface layer is 2cm~3cm. The base filling is layered and compacted. The thickness of each layer is less than or equal to 5cm.

[0061] Step 5: Planting plants in the soil of the enclosed soil space 2 and each planting mold 4, and maintaining them to form a root-soil complex in the planting mold 4; the planted plants are alfalfa, ryegrass, or a mixture of alfalfa and ryegrass;

[0062] Step 6: cutting and separating each measuring unit 3 to cut off the plant root system between adjacent measuring units 3, and cutting and separating the soil circle in the soil space 2 and the plant root system in the soil circle from the plant body;

[0063] Step 7: Remove the circular enclosure 1;

[0064] Step 8: Take a measurement unit 3 that has not been measured and place it between the first blocking member 6 and the loading device;

[0065] Step 9: Apply force to the planting mold 4 at a constant speed through the loading device until shear failure occurs at the junction of 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 force;

[0066] Step 10: Calculate the shear stress at the junction of the bottom of the root-soil complex and the top surface of the rock block 5 when shear failure occurs;

[0067] Step 11: Repeat steps 8 to 10 until all the measurement units 3 have completed the measurement.

[0068] The present embodiment provides a method for measuring the shear strength of the junction between the root-soil complex and the slope rock, which is provided by setting an annular enclosure 1 and a soil-enclosed space 2. The soil-enclosed space 2 is used to accommodate planting soil and plants, so as to surround the outer side of the implant, thereby achieving effective fixation and limitation of the implant as a whole. The implant can be divided into several measuring units 3, so as to facilitate shear tests on different measuring units 3 to obtain multiple sets of shear stress calculation results, thereby improving the accuracy of the measurement results. In each measuring unit 3, the planting mold 4 can not only provide a molding space for the molding of the root-soil complex, but also effectively protect the root-soil complex when the implant is divided into several measuring units 3, effectively avoiding disturbance of the root-soil complex caused by the division of the implant, thereby improving the accuracy of the measurement results. In addition, the soil-enclosed space 2 accommodates planting soil and plants, which can more realistically simulate the actual situation of the root-soil complex and improve the degree to which the measuring unit 3 is close to the actual situation.

[0069] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A device for measuring the shear strength of the junction between a root-soil complex and a slope rock, characterized by: It comprises a planting device and a shear stress measuring device; the planting device comprises an annular enclosure and a planting body, the annular enclosure is arranged around the planting body, a soil space is left between the inner side of the annular enclosure and the outer side of the planting body, the soil space is used to accommodate planting soil and plants, the planting body can be divided into a plurality of measuring units, the measuring units comprise a planting mold, a root-soil complex and a rock block, the top surface of the rock block can support 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 comprises a first blocking member, a loading device and a force measuring device, the measuring unit is used to be placed between the first blocking member and the loading device, the first blocking member can be against the side of the rock block, the loading device can apply a force to the planting mold, the force can cause shear failure at the junction of 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.

2. The device for measuring the shear strength of the junction between a root-soil complex and a slope rock according to claim 1, characterized in that: The top surface of the rock block is a rough surface, the top surface of the rock block is uneven, and a number of criss-cross cracks are opened on the top surface of the rock block, and the cross-section of the cracks is V-shaped, wide at the top and narrow at the bottom; the depth of the cracks is less than 10 cm; the spacing between any two adjacent transverse cracks is less than or equal to 4 cm, and the spacing between any two adjacent longitudinal cracks is less than or equal to 4 cm; the width of the cracks is 1 mm to 3 mm, and the cracks include a first crack and a second crack, the width of the first crack is greater than the width of the second crack, the first transverse cracks and the second transverse cracks are alternately distributed, and the first longitudinal cracks and the second longitudinal cracks are alternately distributed; a separation pad is provided between the implant mold and the rock block.

3. The device for measuring the shear strength of the junction between a root-soil complex and a 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 is aligned up and down with the rock block, the gaps between the planting molds are aligned up and down with the gaps between the rock blocks, and the bottom surfaces of all the planting molds are on the same horizontal plane.

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

5. The device for measuring the shear strength of the junction between a root-soil complex and slope rock according to claim 1, characterized in that: A plurality of rows of through holes are provided on the side wall of the implantation mold, with a plurality of through holes in each row, and any two upper and lower adjacent rows of through holes are staggered with each other.

6. The device for measuring the shear strength of the junction between a root-soil complex and 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 holes is 6 mm, and the distance from the through holes in the bottom row to the bottom surface of the implant mold is 3 mm.

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

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

9. The device for measuring the shear strength of the joint between a root-soil complex and slope rock according to claim 1, characterized in that: 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, 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, and the second blocking member can block the jack; the jack can apply the force to the loading plate and the planting mold.

10. A method for measuring the shear strength of a joint between a root-soil complex and a rocky slope, using the device for measuring the shear strength of a joint between a root-soil complex and a rocky slope as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: Arrange the rocks so that they are in close contact with each other; Step 2: surround the outer side of the assembled rock block with a circular enclosure, and leave a soil space between the inner side of the circular enclosure and the outer side of the assembled rock block; Step 3: Place each planting mold on each rock block one by one; Step 4: The preparation of planting soil includes determining the proportion of planting soil and filling of planting soil. The proportion of planting soil is consistent with the proportion of planting soil used on the project site. The planting soil is filled into the space inside the circular enclosure. The filling of planting soil is divided into base filling and surface filling. The thickness of the base layer is 10cm~12cm, and the thickness of the surface layer is 2cm~3cm. The base filling is layered and compacted. The thickness of each layer is less than or equal to 5cm. Step 5: Planting plants in the soil in the circle and in each planting mold, and maintaining them to form a root-soil complex in the planting mold; the planted plants are alfalfa, ryegrass, or a mixture of alfalfa and ryegrass; Step 6: Cut and separate each measurement unit to cut off the plant root system between adjacent measurement units, and cut and separate the soil circle in the soil circle and the plant root system in the soil circle from the plant body; Step 7: Remove the circular enclosure; Step 8: Take a measurement unit that has not been measured and place it between the first blocking member and the loading device; Step 9: Apply force to the planting mold at a uniform speed through the loading device until shear failure occurs at the junction of 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 at the junction of the bottom of the root-soil complex and the top surface of the rock block when shear failure occurs; Step 11: Repeat steps 8 to 10 until all the test monomers have been tested.

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