A device and method for testing the shear strength of a circular structure surface

Abstract

The application provides a circular structure surface ring shearing test device and method, which comprises a torsion driving part, a sample shearing part, a torque measuring part, a normal pressure part and a rotating guide rail part. The sample shearing part is detachably movable and comprises a first shearing box which is composed of a transmission base as an internal limiting part and a first movable element fixed on a rotating base, and a second shearing box which is composed of a second movable element fixed on a fixed base and closely attached to the periphery of the first shearing box. The first shearing box can rotate relative to the second shearing box to generate ring shearing. The application can be applied to the ring shearing mechanical response test of the circular structure surface under the action of the circumferential normal load, and is suitable for the simulation research of the ring shearing of the circular structure surface under the action of the ring shearing at different positions and different load sizes. The shearing box shape has great flexibility, can apply different load sizes at different positions, and can accurately obtain the mechanical parameters of the material and the interface bonding and sliding ability parameters of different materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ring shear test device, and relates to a ring shear test device and method suitable for circular structural surface, in particular to a ring shear test device and method for testing shear characteristics of different engineering base circular contact interface, and especially to a ring shear test device and method with circular structural surface as shear surface and ring direction as contact interface shear direction and flexible normal pressure. BACKGROUND

[0002] With the rapid development of science and technology today, whether from a macroscopic or microscopic point of view, the interface problem has become ubiquitous and has become one of the technical problems that must be overcome by scientific and engineering and technical personnel. From a macroscopic point of view, various materials and material combinations, such as the contact interface of pipes and soil, the contact interface of pile foundations and soil, the contact interface of various column structures and other materials, the coating interface of thin film coating materials, the mechanical action interface between transmission parts, the combination interface of functional devices and load-bearing components, and the interlayer of composite material laminates, have a very important influence on the load-carrying capacity, efficiency, service life, reliability, etc. of the material or structure as a whole; from a microscopic point of view, the mechanical behavior of the interface between fibers and matrix materials, grain boundaries, particle reinforcements and matrix materials, and inclusions and matrix materials, has important significance for the performance design and development of advanced materials and the accurate evaluation of their structural life.

[0003] Since the material contact surface is a weak structural layer relative to the material matrix, damage and destruction of most components occurs or originates from the interface, and energy loss in transmission systems is mainly caused by friction at the interface. With the rapid development of science and technology, the industrial application of various functional materials, composite materials and other advanced materials is expanding, and the mechanical properties of contact interfaces between different matrices are attracting more and more attention and attention. For the macroscopic shear mechanical properties of material interfaces, scholars at home and abroad have invented many shear methods and test devices, but most of these shear test devices simplify the material model and directly shear the material interface as a planar structure.

[0004] In actual engineering, the contact interface of structures such as pipes, piles and columns with other materials is usually a circular structural surface. In some studies on circular structural surfaces, due to the constraints of the loading method, the longitudinal shear mechanical properties of the circular structural surface are mainly studied, and the circular structural surface of the material is often affected by longitudinal and circumferential double effects in actual engineering. It is difficult to reflect the true mechanical properties of the interface from the longitudinal angle. For example, patent document CN110044726A discloses a ring shear apparatus test system suitable for soil-rock contact surface, which can simulate the progressive failure behavior of soil mass along the structural surface on the rock slide bed, including an upper shear box and a lower shear box. The rotating platform is detachably connected to the lower shear box, and the upper shear box is provided with a pore water pressure sensor. Patent document CN110987660A discloses a ring shear test device, which can simulate the strength relationship of the contact surface under different loads and deformation conditions, and can simultaneously obtain the shear displacement-shear stress relationship and the shear displacement-normal displacement relationship. Although the shear methods provided by the two schemes are circumferential shear, the shear surface is not along the circular structural surface of the material.

[0005] Therefore, it is of great engineering significance to develop a new test device and test method for the circumferential shear properties of the circular structural surface. Therefore, it is urgent to develop a circumferential shear test device and method suitable for the circular structural surface, the circumferential shear direction of the contact interface and the flexible normal pressure. SUMMARY

[0006] In view of the defects of the prior art, the technical problem to be solved by the present application is to provide a circular structural surface circumferential shear test device and method, which is applied to the circumferential shear mechanical response test of the circular structural surface under the action of the circumferential normal load, to adapt to the simulation research of the circumferential shear of the circular structural surface under the action of different positions and different load sizes. The shear box shape has great flexibility, different size loads can be applied at different positions, the mechanical parameters of the material and the material interface bonding and sliding ability parameters can be accurately obtained, which is helpful for the research on the circumferential shear mechanical mechanism of the pipe, pile foundation, column and other circular structural surfaces and the interface strength mechanism under the action of different circumferential loads.

[0007] In order to solve the above technical problems, the present application adopts the following technical scheme:

[0008] Firstly, the present application provides a circular structural surface circumferential shear test device, comprising:

[0009] The torsion driving part, the sample shear part, the torque measuring part, the normal pressure part and the rotating guide rail part, wherein:

[0010] The torque driving part is a servo motor, which applies torsional power through a first transmission shaft;

[0011] The sample shearing component is a movable detachable sample shearing component, comprising a first shearing box composed of a transmission base as an internal limiting component and a first movable element mounted and fixed on a rotating base, and a second shearing box composed of a second movable element mounted on a fixed base and closely attached to the periphery of the first shearing box; the first shearing box has a first accommodating groove, and the second shearing box has a second accommodating groove, and the groove of the second accommodating groove is in communication with the groove of the first accommodating groove to form an accommodating cavity for accommodating a sample to be tested; the rotating base of the first shearing box is in transmission connection with the first transmission shaft, the first shearing box can rotate relative to the second shearing box to produce a ring shearing, and the contact surface of the internal material A in the first shearing box and the external material B in the second shearing box is a shearing surface.

[0012] The torque measuring component is a double-flange torque sensor, and the upper flange and the lower flange are fixedly connected with the fixed disc and the torque transmission disc respectively (generally fixed by fixed bolts); the fixed disc is in transmission connection with the first transmission shaft, and the torque transmission disc is connected with the transmission base through the connecting column; the transmission base is fixed on the rotating base, and the transmission base is in transmission connection with the first transmission shaft.

[0013] The normal pressure component is at least one, which is used to apply different sizes of normal load to different positions of the same shear sample or to apply different sizes of normal load to multiple shear samples to simulate the real service environment.

[0014] The rotating guide rail component is arranged on the device bottom plate and connected with the normal pressure component, which is used to support at least one normal pressure component and can drive the normal pressure component to rotate around the first transmission shaft to adjust the position and direction of the normal load applied by the normal pressure component to the shear sample.

[0015] In operation, the rotating base serves as the bottom component of the first shearing box, and the transmission base rotates under the driving of the first transmission shaft to drive the rotating base to rotate, so that the first shearing box rotates relative to the second shearing box, the sample in the box produces ring shearing, and the resistance suffered by the sample is sequentially transmitted through the rotating base, the transmission base, the connecting column, the torque transmission disc, and the lower flange of the double-flange torque sensor, and the lower flange and the upper flange produce relative torsion to measure the torque.

[0016] In one of the schemes, the movable detachable sample shearing component is a fan ring-shaped sample shearing component, which is suitable for fan ring-shaped shear samples.

[0017] The first movable element of the first shear box comprises two internal fixed blocks and an internal upper fixed top plate; the transmission base 1 is used as an internal limiting part, the two internal fixed blocks are arranged at intervals as two side limiting parts, and the internal upper fixed top plate is used as an upper limiting part, which is fixedly connected with the two internal fixed blocks arranged at intervals and is fixed on the rotating base (usually fixed by fixed bolts), thereby forming the first shear box on the rotating base and forming a fan ring-shaped first accommodating groove;

[0018] The second movable element of the second shear box comprises two external fixed blocks and an external upper fixed top plate, the two external fixed blocks are arranged at intervals as two side limiting parts and are fixed on the fixed base, and the external upper fixed top plate is arranged close to the internal upper fixed top plate as an upper limiting part and is fixedly connected with the two external fixed blocks arranged at intervals and is fixed on the fixed base 7 (usually fixed by fixed bolts), thereby forming the second shear box on the fixed base and forming a fan ring-shaped second accommodating groove, and the second shear box is fixed on the bottom plate through the fixed base 7; the groove opening of the second accommodating groove is communicated with the groove opening of the first accommodating groove to form a fan ring-shaped accommodating cavity for accommodating a sample to be tested.

[0019] Further,

[0020] The number of the first shear box and the second shear box is at least one, when the number of the first shear box and the corresponding second shear box is multiple, a plurality of groups of the first shear box composed of two internal fixed blocks arranged at intervals and an internal upper fixed top plate are fixedly installed on the rotating base, and a plurality of groups of the second shear box formed by two external fixed blocks arranged at intervals and an external upper fixed top plate are fixedly installed on the fixed base in correspondence, and the plurality of first shear boxes and the corresponding second shear boxes form a plurality of accommodating cavities, which can realize ring shear of a plurality of fan ring-shaped samples.

[0021] More specifically, the internal fixed block and the external fixed block are fan ring-shaped, can be matched with the fan ring-shaped sample, and can firmly fix the sample on the left and right sides; the other side can form another shear box with other fixed blocks to shear a plurality of fan ring-shaped samples.

[0022] Preferably, the internal fixed block and the external fixed block are provided with bolt holes in the radial direction, which can ensure the firmness and the limiting function of the fixed block on the sample.

[0023] Further,

[0024] The thickness, radius, corresponding central angle size, position and other factors of the internal fixed block and the internal upper fixed top plate of the first shear box and the external fixed block and the external upper fixed top plate of the second shear box can be adjusted according to the thickness, radius, corresponding central angle size and position of the sample to be sheared, so as to adapt to samples with different thickness, radius, central angle size and position.

[0025] The structural components of the first and second shear boxes are fixed by fixing bolts and can be removed and replaced, so that the thickness, radius, corresponding central angle size and installation position of the sample can be adjusted according to requirements. For a sample with a small central angle, multiple internal fixed blocks and an internal upper fixed top plate can be installed simultaneously, and the external fixed blocks and the external upper fixed top plate of the second shear box can realize the circumferential shear of multiple fan-shaped ring samples and improve the test efficiency.

[0026] Preferably,

[0027] In use, a pressure sensor is arranged on the contact surface between the shear sample and the internal fixed block and the external fixed block. The pressure sensor should be as close as possible to the position of the shear surface, and is used for secondary confirmation of the data measured by the torque sensor.

[0028] Preferably,

[0029] The internal fixed block and the external fixed block are in the same radial direction and the two end surfaces are flush; the two end surfaces of the internal upper fixed top plate and the external upper fixed top plate are flush, and the end surface of the same side of the internal upper fixed top plate and the external upper fixed top plate is flush with the end surface of the internal fixed block and the external fixed block fixed thereto.

[0030] Preferably,

[0031] The upper end surfaces of the internal fixed block and the external fixed block are in the same horizontal plane; the upper end surfaces of the internal upper fixed top plate and the external upper fixed top plate are in the same horizontal plane.

[0032] The upper end surface of the rotating base plate is in the same horizontal plane as the upper end surface of the fixed base plate.

[0033] In another scheme, the movable and detachable sample shear component is a ring-shaped sample shear component, which is suitable for ring-shaped shear samples;

[0034] The first movable element constituting the first shear box only includes an internal upper annular fixed top plate, the transmission base plate is used as an internal limiting component, the internal upper annular fixed top plate is used as an upper limiting component, the inner side of the internal upper annular fixed top plate is tightly attached to the outer side of the transmission base plate and is fixedly installed at a position with a certain height above the rotating base plate (generally fixed by fixing bolts), and the first shear box is formed on the rotating base plate to form an annular first accommodating groove.

[0035] The second movable element constituting the second shear box includes only an outer upper annular fixed top plate. The outer upper annular fixed top plate serves as an upper limit, and its inner side is closely attached to the outer side of the inner upper annular fixed top plate. It is fixedly installed at a certain height above the fixed base (generally fixed by fixing bolts). The second shear box is formed on the fixed base, forming an annular second receiving groove. The second shear box is fixed to the base plate by the fixed base. The groove opening of the second receiving groove communicates with the groove opening of the first receiving groove to form an annular receiving cavity for accommodating the test sample.

[0036] In use, holes are drilled at the fixing bolt positions of the annular specimen, and the specimen is fixed by the fixing bolts. The torsional force for shearing the annular specimen is mainly driven by the servo motor through the first transmission shaft to drive the fixing bolts to shear the specimen.

[0037] Preferably, the inner upper annular fixed top plate and the outer upper annular fixed top plate are on the same horizontal plane; the upper end surface of the rotating chassis and the upper end surface of the fixed chassis are on the same horizontal plane.

[0038] Specifically, the installation height of the inner upper annular fixed top plate from the top of the rotating chassis and the installation height of the outer upper annular fixed top plate from the top of the fixed chassis are adjusted according to the thickness of the annular sample to accommodate annular samples of different thicknesses.

[0039] In the above scheme, for the fan-shaped annular shear component, the first shear box and the second shear box in the annular shear component, in order to facilitate the observation of the shear failure process, the inner upper fixed top plate and the outer upper fixed top plate in the fan-shaped annular shear component, and the inner upper annular fixed top plate and the outer upper annular fixed top plate in the annular shear component can be separated by a certain distance at the shear circular structural surface; for samples with high strength, the upper fixed top plate can be removed.

[0040] Furthermore,

[0041] The normal pressure-applying component mainly consists of a pressure-applying motor, a second drive shaft, a pressure plate, and a pressure sensor. The pressure sensor is connected to the pressure-applying motor. The shape of the pressure plate can be adjusted according to the outer wall of the sheared sample. The pressure-applying motor drives the second drive shaft to apply a load to the outer wall of the sample through the pressure plate. Because the pressure plate is identical to the outer wall of the sample, and the second drive shaft acts in the middle of the pressure plate, the pressure is directed towards the axis of the drive shaft, ensuring strict normal pressure application. This ensures uniform force on the sample and avoids eccentric compression. The load is evenly distributed on the outer wall of the sample, and the pressure direction points towards the center, guaranteeing strict normal load application.

[0042] Furthermore,

[0043] The rotating guide rail part is mainly composed of a support column, a sliding block and a guide rail, one end of the support column is fixed on the sliding block, the other end of the support column is connected with the normal pressure component, the guide rail is a circular guide rail, and the sliding block can slide in the guide rail, so that the normal pressure component is driven to rotate around the first transmission shaft, and different loads of different sizes are applied to different positions of the shear sample.

[0044] In the scheme, the support column, the sliding block and the pressing plate rotate around the same rotating shaft (the first transmission shaft), the pressure applied by the pressing motor can be strictly perpendicular to the shear surface, the load acting position of the support column supporting the pressing motor and the sample is in the same horizontal plane, the support column ensures that the pressing motor and the shear sample are in the same horizontal plane, and the horizontal normal pressure is ensured; the guide rail is a circular guide rail, the sliding block can freely move in the guide rail, and the pressure can be applied to different positions of the sample; the sliding rail can support the existence of multiple normal pressure components, different loads of different sizes can be applied to different positions of the sample, and the needs of complex stress conditions can be met.

[0045] Further,

[0046] The servo motor applies the ring shear force through fixed angular velocity or through fixed torque.

[0047] The application also provides a ring shear test method using the ring shear test device with the circular structure surface, and specifically comprises the following steps:

[0048] S1, according to the shape of the sample to be tested, the first movable element and the second movable element are selected, the corresponding installation positions are selected on the rotating base plate and the fixed base plate, and the first shear box and the second shear box are installed, the sample to be tested is fixed in the first shear box and the second shear box, and the contact surface (interface) between the internal material A in the first shear box and the external material B in the second shear box is a shear surface;

[0049] S2, the rotating guide rail part is adjusted, so that the normal pressure component and the sample to be tested are in the same sector area, the center surfaces of the two are located in the same horizontal plane, and the pressure applying direction of the normal pressure component is directed to the shaft center of the first transmission shaft of the servo motor, so that the load is strictly applied in the normal direction;

[0050] S3, the pressing motor of the normal pressure component is started, and the pressing plate is lightly attached to the outer wall of the sample to be tested, and the appropriate normal load is applied;

[0051] S4, the servo motor is started, the rotating base plate is used as the bottom part of the first shear box, and under the driving of the first transmission shaft, the first shear box is rotated relative to the second shear box, so that the sample is subjected to ring shear in the appropriate loading mode;

[0052] S5, when the sample ring is sheared, the resistance is sequentially through the rotating base, the transmission base, the connecting column and the transmission disc, and is transmitted to the lower flange of the double-flange torque sensor, the lower flange and the upper flange are relatively twisted, and the double-flange torque sensor measures the real-time torque; the pressure sensor in the normal pressure component obtains the real-time normal load;

[0053] S6, the influence of the thickness, the radius, the central angle size, the material type, the load action size and position, the shear surface radius and other factors on the ring shear mechanical properties of the circular structure surface can be obtained by testing the acting force under different parameter conditions.

[0054] The present application can realize the following technical effects:

[0055] The present application can realize the following technical effects:

[0056] The present application can realize the following technical effects:

[0057] The annular shear test device provided by the application can perform annular shear on a single material, and the function is similar to that of a direct shear test and a conventional ring shear test, and the related mechanical properties of the material can be obtained. Meanwhile, unlike the traditional shear, the shear surface is circular, which is more in line with the torsion of engineering structures, such as pipelines, piles, columns and the like. Moreover, the annular shear test device provided by the application can perform annular shear on a sample with a circular structure surface at the interface of two materials, and can deeply explore the bonding and sliding performance of the material interface along the annular direction. Therefore, the test device of the application can obtain the internal friction angle and cohesive force and the like of the single material, and can also obtain the shear mechanical properties of the circular structure surface for the combined sample of two materials. The annular shear test device can provide reliable reference for the research on the annular stress mechanism of the circular structure surface of the pipeline, pile foundation, column and the like and other materials, the technical construction standard, daily maintenance, repair and repair effect evaluation.

[0058] The annular shear test device provided by the application can be applied to fan ring-shaped and ring-shaped shear samples. Meanwhile, a plurality of normal pressure components composed of a pressurizing motor, a transmission shaft, a pressurizing plate, a motor fixing component, a pressure sensor, a support column and a sliding block can be installed on the guide rail of the rotating guide rail component to simultaneously apply a normal load. For a ring-shaped sample, different normal loads can be applied to different positions of the sample through a plurality of normal pressure devices to simulate a real service environment. For a sample with a small central angle, a plurality of internal and external fixed blocks and internal and external upper fixed top plates can be simultaneously installed to form a plurality of first shear boxes and second shear boxes, so that annular shear of a plurality of fan ring-shaped samples is realized, and the test efficiency is improved.

[0059] The accommodating cavities formed by the first and second shear boxes do not need to be filled with the sample in the radial direction, and only need to make the shear surface located at the contact surface of the shear box. Since the sample is sheared along the circular structure surface, the sample will not be loose in the radial direction.

[0060] In summary, the annular shear test device and method for the circular structure surface provided by the application can be applied to annular shear mechanical response tests of the circular structure surface under the action of a circumferential normal load. The shear box has great flexibility in shape, can be applied to samples of different sizes, can apply different loads to different positions of the sample, can accurately obtain the mechanical parameters of the material and the bonding and sliding ability of the material interface, and is helpful for the research on the annular shear mechanical mechanism of the circular structure surface of the pipeline, pile foundation, column and the like and the interface strength mechanism under the action of different annular loads. BRIEF DESCRIPTION OF DRAWINGS

[0061] In order to make the technical solutions of the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only need to be some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0062] Figure 1 It is a schematic diagram of the overall structure of the ring shear test device of the embodiment of the present application (the first to third fixing members are not shown).

[0063] Figure 2 It is a schematic diagram of the front structure of the ring shear test device of the embodiment of the present application. Figure 1

[0064] Figure 3 It is a schematic diagram of the installation structure of the torque measuring component of the embodiment of the present application.

[0065] Figure 4 It is a schematic diagram of the structure of the fan ring sample shear component of the embodiment 1 of the present application.

[0066] Figure 5 It is a schematic diagram of the structure of the ring sample shear component of the embodiment 2 of the present application.

[0067] Figure 6 It is a schematic diagram of the fan ring sample of the embodiment 1 of the present application.

[0068] Figure 7 It is a schematic diagram of the ring sample of the embodiment 2 of the present application.

[0069] Figure 8 It is a schematic diagram of the assembly structure of the normal pressure component and the rotating guide rail component of the embodiment of the present application.

[0070] Figure 9 It is a schematic diagram of the structure of the first fixing member of the embodiment of the present application.

[0071] Figure 10 It is a schematic diagram of the structure of the second fixing member of the embodiment of the present application.

[0072] Figure 11 It is a schematic diagram of the structure of the third fixing member of the embodiment of the present application.

[0073] The description of the reference signs of the present application is as follows:

[0074] Reference Name Reference Name 1 Transmission chassis 2 Internal fixed block 3 Internal upper fixed top plate 4 Rotary chassis 5 Fixed bolt 6 External fixed block 7 Fixed chassis 8 External upper fixed top plate 9 Pressing plate 10 Bottom plate 11 Connecting column 12 Torque transmission disc 13 Double-flange torque sensor 14 Servo motor 15 First transmission shaft 16 Pressing motor 17 Second transmission shaft 18 Pressure sensor 19 Support column 20 Slide block 21 Guide rail 22 Internal upper annular fixed top plate 23 External upper annular fixed top plate 24 Fixed disc 25 Interface 26 Sector ring-shaped internal material A 27 Sector ring-shaped external material B 28 Annular internal material A 29 Annular external material B 30 Threaded hole 31 First fixing member 32 Second fixing member 33 Third fixing member DETAILED DESCRIPTION

[0075] ​The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0076] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0077] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0078] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0079] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0080] Example 1

[0081] like Figures 1-3 As shown in Figures 4, 6, and 8, this embodiment provides a circumferential shear test apparatus for a circular structural surface, comprising:

[0082] Torsion drive component, sample shearing component, torque measuring component, normal pressure component, rotary guide component, wherein:

[0083] In this embodiment, the torque drive component is a servo motor 14, which applies torsional power through the first transmission shaft 15.

[0084] The sample shearing component is a movable detachable sample shearing component, comprising: a first shearing box formed by a transmission base plate 1 as an internal limiting component and a first movable element mounted and fixed on a rotating base plate 4, and a second shearing box formed by a second movable element mounted on a fixed base plate 7 and closely attached to the periphery of the first shearing box; the first shearing box has a first accommodating groove, and the second shearing box has a second accommodating groove, and the groove of the second accommodating groove is in communication with the groove of the first accommodating groove to form an accommodating cavity for accommodating a sample to be tested; the first shearing box can rotate relative to the second shearing box to generate a ring shearing, and the contact surface of the internal material A in the first shearing box and the external material B in the second shearing box is a shearing surface; the first accommodating groove is used for accommodating the internal material A, and the second accommodating groove is used for accommodating the external material B.

[0085] As a preferred embodiment, the movable detachable sample shearing component provided by the embodiment is a fan ring-shaped sample shearing component, which is suitable for fan ring-shaped shearing samples (see Figure 4 and Figure 6 ).

[0086] The first movable element constituting the first shearing box comprises two internal fixed blocks 2 and an internal upper fixed top plate 3; the outer periphery of the transmission base plate 1 is used as an internal limiting component, the two internal fixed blocks 2 are arranged at intervals as two side limiting components, and the internal upper fixed top plate 3 is used as an upper limiting component, which is fixedly connected with the two internal fixed blocks 2 arranged at intervals and is fixed on the rotating base plate 4 through a fixed bolt 5, thereby forming the first shearing box on the rotating base plate 4 and forming a fan ring-shaped first accommodating groove.

[0087] The second movable element constituting the second shearing box comprises two external fixed blocks 6 and an external upper fixed top plate 8; the two external fixed blocks 6 are arranged at intervals as two side limiting components and are fixed on the fixed base plate 7, and the external upper fixed top plate 8 is arranged closely to the internal upper fixed top plate 3 as an upper limiting component, which is fixedly connected with the two external fixed blocks 6 arranged at intervals and is fixed on the fixed base plate 7 through a fixed bolt 5, thereby forming the second shearing box on the fixed base plate 7 and forming a fan ring-shaped second accommodating groove, and the second shearing box is fixed on a base plate 10 through the fixed base plate 7; the groove of the second accommodating groove is in communication with the groove of the first accommodating groove to form a fan ring-shaped accommodating cavity for accommodating a sample to be tested.

[0088] As a preferred embodiment, in the embodiment, the shear parts of the fan-shaped ring sample are at least one, and the number of the first shear box and the second shear box is at least one. When the number of the first shear box and the corresponding second shear box is multiple, a plurality of groups of the first shear box composed of two interval arranged internal fixed blocks 2 and internal upper fixed top plates 3 are fixedly installed on the rotating base plate 4, and a plurality of groups of the second shear box formed by two interval arranged external fixed blocks 6 and external upper fixed top plates 8 are fixedly installed on the fixed base plate 7. The plurality of first shear boxes and the corresponding second shear boxes form a plurality of containing cavities, which can realize the circumferential shear of a plurality of fan-shaped ring samples.

[0089] As a preferred embodiment, in the embodiment, the internal fixed blocks 2 and the external fixed blocks 6 are fan-shaped, which can cooperate with the fan-shaped ring sample to firmly fix the sample on the left and right sides, and the other side can form another shear box with other fixed blocks to shear a plurality of fan-shaped ring samples. It can be understood that, as another implementable scheme, the internal fixed blocks 2 and the external fixed blocks 6 can also be long strips, which are respectively installed in the radial direction on the rotating base plate 4 and the fixed base plate 7 to form the first shear box and the second shear box with fan-shaped notches with the corresponding fixed top plates.

[0090] The internal fixed blocks 2 and the external fixed blocks 6 are provided with bolt holes in the radial direction, which can ensure the firmness of the blocks and the limiting function of the sample.

[0091] The thickness, radius, corresponding central angle size, position and other factors of the internal fixed blocks 2 and the internal upper fixed top plates 3 constituting the first shear box and the external fixed blocks 6 and the external upper fixed top plates 8 constituting the second shear box can be adjusted according to the thickness, radius, corresponding central angle size, position of the sample to be sheared, so as to adapt to samples with different thickness, radius, central angle size and position. Since the structural parts of the first and second shear boxes are fixed by fixed bolts, they can be removed and replaced, so that the thickness, radius, corresponding central angle size and installation position of the sample can be adjusted according to the requirements. For a sample with a small central angle, a plurality of internal fixed blocks 2, internal upper fixed top plates 3, external fixed blocks 6 and external upper fixed top plates 8 can be installed at the same time to realize the circumferential shear of multiple samples and improve the test efficiency.

[0092] When in use, a pressure sensor is arranged on the contact surface between the shear sample and the internal fixed blocks 2 and the external fixed blocks 6, and the pressure sensor should be as close to the shear surface position as possible. The pressure sensor is used for secondary confirmation of the data measured by the torque sensor.

[0093] As a preferred embodiment, the inner fixed block 2 and the outer fixed block 6 are in the same radial direction and the two end faces are flush; the two end faces of the inner upper fixed top plate 3 and the outer upper fixed top plate 8 are flush, and the end face of the same side of the inner upper fixed top plate 3 and the outer upper fixed top plate 8 is flush with the end face of the inner fixed block 2 and the outer fixed block 6 fixed thereto.

[0094] The upper end faces of the inner fixed block 2 and the outer fixed block 6 are in the same horizontal plane; the upper end faces of the inner upper fixed top plate 3 and the outer upper fixed top plate 8 are in the same horizontal plane.

[0095] The upper end face of the rotating bottom plate 4 is in the same horizontal plane as the upper end face of the fixed bottom plate 7.

[0096] As a preferred embodiment, the torque measuring component in the embodiment is a double-flange torque sensor 13, the upper flange of the double-flange torque sensor 13 is fixed with the fixed disc 24 connected to the first transmission shaft 15 through the fixing bolt 5, and the lower flange is fixed with the torque transmission disc 12 through the fixing bolt 5; the torque transmission disc 12 is connected with the transmission bottom plate 1 through the connecting column 11; the transmission bottom plate 1 is fixed on the rotating bottom plate 4 through the fixing bolt, and the transmission bottom plate 1 is in transmission connection with the first transmission shaft. Figure 3 As shown in the figure, the upper end of the connecting column 9 passes through the round hole reserved in the torque transmission disc 12; the lower end of the connecting column 9 is fixedly connected with the transmission bottom plate 1 through the first fixing part 31 and the fixing bolt; the transmission bottom plate 1 is fixedly connected with the first transmission shaft 15 through the second fixing part 32 and the fixing bolt, so as to realize the transmission connection between the transmission bottom plate 1 and the first transmission shaft 15.

[0097] In operation, the servo motor 14 applies a torsional force through the first transmission shaft 15, the servo motor 14 drives the first transmission shaft 15 to rotate, and the fixed disc 24 and the transmission bottom plate 1 rotate with the first transmission shaft 15. The rotating bottom plate 4 is the bottom part of the first shear box, when the transmission bottom plate 1 is driven to rotate by the first transmission shaft 15, the rotating bottom plate 4 will rotate with the transmission bottom plate 1, so that the first shear box rotates relative to the second shear box, the sample in the shear box is subjected to ring shear, and the resistance of the sample is sequentially transmitted to the lower flange of the double-flange torque sensor 13 through the rotating bottom plate 4, the transmission bottom plate 1, the connecting column 11, and the torque transmission disc 12, and the relative torsion between the lower flange and the upper flange is generated, so that the torque is measured. The servo motor 14 in the embodiment can apply ring shear force by fixing the angular velocity, or can apply ring shear force by fixing the torque.

[0098] As a preferred embodiment, the normal pressure component in the embodiment is at least one, which is used to apply different normal loads to different positions of the same shear sample or to apply different normal loads to multiple shear samples to simulate the real service environment. When the fan-shaped shear sample components are multiple (not shown in the drawings), generally, one fan-shaped shear sample component corresponds to at least one normal pressure component.

[0099] As a preferred embodiment, the normal pressure component in the embodiment mainly consists of a pressure motor 16, a second transmission shaft 17, a pressure plate 9, and a pressure sensor 18. The pressure sensor 18 is connected to the pressure motor 16, the pressure plate 9 can be adjusted according to the outer wall of the shear sample, and the pressure motor 16 drives the second transmission shaft 17 to apply load to the outer wall of the sample through the pressure plate 9. Because the pressure plate 9 is the same as the outer wall of the sample, the second transmission shaft 17 acts on the middle of the pressure plate 9, so that the pressure is strictly normal to the transmission shaft axis, ensuring that the sample is uniformly stressed and avoiding eccentric compression load. The pressure direction points to the center of the circle, ensuring that the load is strictly applied in the normal direction.

[0100] As a preferred embodiment, as shown in Figure 8 the pressure plate 9 is connected to the second transmission shaft 17 through a third fixing member 33 and a fixing bolt.

[0101] As a preferred embodiment, the rotating guide rail component in the embodiment is arranged on the device bottom plate 10 and connected to the normal pressure component, which is used to support at least one normal pressure component and can drive the normal pressure component to rotate around the first transmission shaft 15 to adjust the position and direction of the normal load applied by the normal pressure component to the shear sample.

[0102] In the embodiment, the rotating guide rail component mainly consists of a support column 19, a sliding block 20, and a guide rail 21. One end of the support column 19 is fixed on the sliding block 20, the other end of the support column 19 is connected to the normal pressure component, the guide rail 21 is a circular ring guide rail, and the sliding block 20 can slide in the guide rail 21, thereby driving the normal pressure component to rotate around the first transmission shaft 15 to apply different loads to different positions of the shear sample. As a preferred embodiment, as shown in Figure 8 the lower end of the support column 19 is fixedly connected to the sliding block through a first fixing member 31. The pressure motor 16, the second transmission shaft 17, the pressure sensor 18, and the pressure plate 9 form an integral whole, which is fixed to the upper end of the support column 19 through a motor fixing member and a fixing bolt.

[0103] In this design, the support column 19, slider 20, and pressure plate 9 all rotate around the same axis of rotation (first transmission shaft 15), ensuring that the pressure applied by the pressure motor 16 is strictly perpendicular to the shear plane. The support column ensures that the load application position of the pressure motor and the sample is on the same horizontal plane, and the support column 19 ensures that the pressure motor 16 and the shear sample are on the same horizontal plane, ensuring that the normal pressure is applied horizontally. The guide rail 21 is a circumferential circular rail, and the slider 20 can move freely within the guide rail 21, allowing pressure to be applied to different positions of the sample. The guide rail 21 has sufficient space to support the presence of multiple normal pressure components, allowing different loads to be applied to different positions of the sample, meeting the needs of complex stress conditions.

[0104] Example 2

[0105] like Figures 1-3 As shown in Figures 5, 7, and 8, this embodiment provides another circular shear test apparatus, including: a specimen shearing component, a torque measuring component, a torsion drive component, a normal pressure component, and a rotating guide component. Unlike the circumferential shear test apparatus provided in Embodiment 1, the movable and detachable specimen shearing component in this embodiment is an annular specimen shearing component, suitable for annular shear specimens (see Figure 1). Figure 5 and Figure 7 );

[0106] The first movable element constituting the first shearing box includes only the inner upper annular fixed top 22, with the transmission chassis 1 as the internal limiting component and the inner upper annular fixed top plate 22 as the upper limiting component. The inner side of the inner upper annular fixed top plate 22 is closely attached to the outer side of the transmission chassis 1 and is fixedly installed at a certain height above the rotating chassis 4 by fixing bolts 5, forming the first shearing box on the rotating chassis 4 and forming an annular first receiving groove.

[0107] The second movable element constituting the second shear box includes only the outer upper annular fixed top plate 23. The outer upper annular fixed top plate 23 serves as the upper limit, and its inner side is closely attached to the outer side of the inner upper annular fixed top plate 23. It is fixedly installed at a certain height above the fixed base plate 7 by fixing bolts 5. The second shear box is formed on the fixed base plate 7, forming an annular second receiving groove. The second shear box is fixed on the base plate 10 by the fixed base plate 7. The groove opening of the second receiving groove communicates with the groove opening of the first receiving groove to form an annular receiving cavity for accommodating the test sample.

[0108] In use, holes are drilled at the fixing bolt 5 position of the annular specimen, and the specimen is fixed by the fixing bolt 5. The torsional force of the annular specimen shearing is mainly driven by the servo motor 14 through the first transmission shaft 15 to drive the fixing bolt 5 to shear the specimen.

[0109] As a preferred embodiment, the inner upper annular fixed top plate 22 and the outer upper annular fixed top plate 23 are in the same horizontal plane; the upper end surface of the rotating base plate 4 and the upper end surface of the fixed base plate 7 are in the same horizontal plane. The installation height of the inner upper annular fixed top plate 22 above the rotating base plate 4 and the installation height of the outer upper annular fixed top plate 23 above the fixed base plate 7 are adjusted according to the thickness of the annular sample, so as to adapt to annular samples of different thicknesses.

[0110] It should be noted that the Figures 9-11 , three different fixing members are provided, wherein the first fixing member and the second fixing member are fixing members of basically the same structure, only different in size, and for the connection with the transmission shaft, since the transmission shaft is relatively thick, the second fixing member with a larger connecting hole is selected. Figure 10 It can be understood that other fixing members of other structures and shapes that can realize the fixed connection of two elements are also within the protection scope of the present application.

[0111] The annular shear test method of the device provided by the present application is as follows:

[0112] The annular shear test method of the annular shear test device provided by the embodiment 1 and the embodiment 2 is basically the same, including the following steps:

[0113] S1, according to the shape of the sample to be tested, selecting the corresponding first movable element and the second movable element, and selecting the corresponding installation position on the rotating base plate 4 and the fixed base plate 7 to install the first shear box and the second shear box, respectively, and placing the sample to be tested in the first shear box and the second shear box, and the shear surface is located at the contact surface (interface) of the first shear box and the second shear box;

[0114] Specifically, for the fan-shaped annular sample, the inner upper fan-shaped annular fixed top plate 3 and the inner fixed fan-shaped annular stopper 2 of the corresponding thickness, radius and corresponding central angle size are selected and the corresponding installation position is selected, and the first shear box of the corresponding specification is formed by being installed on the rotating base plate 4 through the fixed screw 5. At the same time, the outer upper fan-shaped annular fixed top plate 8 and the outer fixed fan-shaped annular stopper 6 are selected and the corresponding installation position is selected, and the second shear box of the corresponding specification is formed by being installed on the fixed base plate 7 through the fixed screw 5. The fan-shaped annular inner material A 26 and the fan-shaped annular outer material B 27 are respectively placed in the first shear box and the second shear box, and the two kinds of material samples have a contact interface 25.

[0115] For the ring sample, the corresponding inner upper ring-shaped fixed top plate 22 and outer upper ring-shaped fixed top plate 23 are selected and fixedly installed on the rotating base plate 4 and the fixed base plate 7 respectively to form a first shear box and a second shear box. The ring-shaped inner material A 28 and the ring-shaped outer material B 29 are placed in the first shear box and the second shear box respectively, and the two material samples have a contact interface 25. In use, the ring sample is punched at the bolt hole 30 position, and the sample is fixed by the fixing bolt 5.

[0116] For the ring shear test device provided in Embodiments 1 and 2, the inner upper fan-shaped fixed top plate 3 and the outer upper fan-shaped fixed top plate 8 in the fan ring shear part, and the inner upper ring-shaped fixed top plate 22 and the outer upper ring-shaped fixed top plate 23 in the ring shear part can be separated by a certain distance at the position of the shear circular structure surface, so as to facilitate observation of the shear failure process. For the sample with high strength, the upper fixed top plate can also be removed.

[0117] S2, adjust the rotating guide rail part so that the normal pressure part and the sample to be tested are in the same fan-shaped area and the center surfaces of the two are located in the same horizontal plane, and the pressure direction of the normal pressure part is directed to the shaft center of the first transmission shaft 15 of the servo motor 14, so as to ensure that the load is strictly applied in the normal direction;

[0118] Specifically, the slider 20 of the rotating guide rail part is moved in the guide rail 21 to adjust the different pressure positions and pressure directions of the normal pressure part on the sample. For the case where multiple normal pressure parts are installed, each normal pressure part is adjusted according to the same method.

[0119] S3, start the pressure motor 16 of the normal pressure part to make the pressure plate 9 closely adhere to the outer wall of the sample to be tested, and apply a suitable normal load;

[0120] S4, start the servo motor 14, and the rotating base plate 4 as the bottom part of the first shear box is driven by the first transmission shaft 15 to rotate the first shear box relative to the second shear box, so as to perform ring shear on the sample in a suitable loading mode;

[0121] S5, when the sample is subjected to ring shear, the resistance is sequentially transmitted through the rotating base plate 4, the transmission base plate 1, the connecting column 11, the transmission disc 12, and the lower flange of the double-flange torque sensor 13, and the lower flange and the upper flange are relatively twisted, and the double-flange torque sensor 13 measures the real-time torque; the pressure sensor 18 of the normal pressure part obtains the real-time normal load;

[0122] S6, the influence of the thickness, the radius, the central angle size, the material type, the load size and position, and the shearing surface radius on the ring shear mechanical property of the circular structure surface can be obtained through the measured force under different parameter conditions.

[0123] The application simplifies the ring shear of the circular structure surface into the direct shear of the plane by applying the rotating torque, so that the force is always perpendicular to the interface normal direction, thereby realizing the research on the ring shear mechanical property of the circular structure surface and solving the problem of the ring shear loading difficulty of the circular structure surface.

[0124] The first shear box and the second shear box are installed by a plurality of movable elements with different sizes through fixing bolts, the thickness, the radius, the corresponding central angle size, and the installation position of the movable elements of the first shear box and the second shear box can be replaced to form shear boxes with different specifications, so that the ring shear of samples with different materials, thicknesses, radii, and corresponding central angle sizes can be realized.

[0125] The normal pressure component can be moved through the guide rail of the rotating guide rail component to adjust different pressure positions of the sample, and the normal pressure component can be installed in multiple to apply different sizes of loads to different positions of the sample to meet the needs of complex stress environment. Therefore, the application can study the influence of the thickness, the radius, the central angle size, the material, the load size and position, and the shearing surface radius on the ring shear mechanical property of the circular structure surface. For the sample with a small central angle, a plurality of internal and external fixed blocks and internal and external upper fixed top plates can be installed to form a plurality of first shear boxes and second shear boxes to realize the ring shear of a plurality of fan ring samples and improve the test efficiency. For the ring sample, a plurality of normal pressure devices can be used to apply different sizes of normal loads to different positions of the sample to simulate the real service environment.

[0126] The annular shear test device can perform annular shear on a single material, and functions similarly to a direct shear test and a conventional annular shear test, and can obtain relevant mechanical properties of the material.

[0127] In summary, the annular shear test device and method provided by the present application can be applied to annular shear mechanical response tests of circular structural surfaces under circumferential normal loads, the shear box has high flexibility in shape, can be applied to test samples of different sizes, can apply different loads of different sizes at different positions of the test sample, can accurately obtain mechanical parameters of the material and material interface bonding and sliding mechanical parameters, and is helpful to the research on annular shear mechanical mechanisms of circular structural surfaces such as pipes, pile foundations and columns and the interface strength mechanisms under different annular loads.

[0128] The above description is only preferred embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made by using the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A circumferential shear test device for a circular structural surface, characterized in that, include: Torsion drive component, sample shearing component, torque measuring component, normal pressure component, rotary guide component, wherein: The torque drive component is a servo motor, which applies torsional power through the first transmission shaft; The sample shearing component is a movable and detachable sample shearing component, comprising: a first shearing box consisting of a transmission chassis as an internal limiting component and a first movable element mounted and fixed on a rotating chassis; and a second shearing box consisting of a second movable element mounted on a fixed chassis close to the periphery of the first shearing box; the first shearing box has a first receiving groove, and the second shearing box has a second receiving groove, the opening of the second receiving groove communicating with the opening of the first receiving groove to form a receiving cavity for receiving the sample to be tested; the rotating chassis of the first shearing box is drivenly connected to a first transmission shaft, and the first shearing box can rotate relative to the second shearing box to generate circumferential shearing, and the contact surface between the internal material A in the first shearing box and the external material B in the second shearing box is the shearing surface; The torque measuring component is a dual-flange torque sensor, with its upper flange and lower flange fixedly connected to a fixed disk and a torque-transmitting disk, respectively; the fixed disk is connected to the first drive shaft, and the torque-transmitting disk is connected to the drive chassis via a connecting column; the drive chassis is fixed on the rotating chassis and is connected to the first drive shaft. The normal pressure component is at least one, used to apply different magnitudes of normal load to different positions of the same shear specimen or to apply different magnitudes of normal load to multiple shear specimens; The rotary guide rail component is mounted on the base plate of the device and connected to the normal pressure component. It supports at least one normal pressure component and can drive the normal pressure component to rotate around the first transmission shaft to adjust the position and direction of the normal pressure component applying normal load to the shear specimen. The movable and detachable specimen shearing component is a switchable fan-shaped specimen shearing component and a ring-shaped specimen shearing component. When shearing a fan-shaped annular sample, the first movable element constituting the first shearing box includes two internal fixed blocks and an inner upper fixed top plate; the transmission chassis serves as an internal limiting component, the two internal fixed blocks are spaced apart as side limiting components, the inner upper fixed top plate serves as an upper limiting component, the inner upper fixed top plate is fixedly connected to the two spaced internal fixed blocks and fixed on the rotating chassis, forming the first shearing box on the rotating chassis, forming a fan-shaped annular first receiving groove; The second movable element constituting the second shear box includes two external fixed blocks and an outer upper fixed top plate. The two external fixed blocks are spaced apart and fixed to the fixed base as side limiting components. The outer upper fixed top plate is set close to the inner upper fixed top plate as an upper limiting component and is fixedly connected to the two spaced external fixed blocks and fixed to the fixed base. The second shear box is formed on the fixed base, forming a fan-shaped annular second receiving groove. The second shear box is fixed to the base plate by the fixed base 7. The groove opening of the second receiving groove communicates with the groove opening of the first receiving groove to form a fan-shaped annular receiving cavity for accommodating the test sample.

2. The circumferential shear test device for a circular structure surface according to claim 1, characterized in that, The number of the first shear box and the second shear box is at least one. When there are multiple first shear boxes and corresponding second shear boxes, multiple sets of first shear boxes consisting of two spaced-apart internal fixed blocks and an inner upper fixed top plate are fixedly installed on the rotating chassis. Correspondingly, multiple sets of second shear boxes consisting of two spaced-apart external fixed blocks and an outer upper fixed top plate are fixedly installed on the fixed chassis. The multiple first shear boxes and corresponding second shear boxes form multiple receiving cavities, which can realize the circumferential shearing of multiple fan-shaped samples.

3. The circular shear test device for a circular structural surface according to claim 1, characterized in that, The thickness, radius, corresponding central angle size, and position of the internal fixing block and inner upper fixing plate that make up the first shearing box, and the external fixing block and outer upper fixing plate that make up the second shearing box, are adjusted according to the thickness, radius, corresponding central angle size, and position of the sample to be sheared, so as to adapt to samples with different thicknesses, radii, central angle sizes, and positions.

4. The circular shear test device for a circular structural surface according to claim 1, characterized in that, The movable and detachable specimen shearing component is a switchable fan-shaped specimen shearing component and a ring-shaped specimen shearing component. When applicable to annular shearing of specimens; the first movable element constituting the first shearing box includes only an inner upper annular fixed top plate, with the transmission chassis as the internal limiting component and the inner upper annular fixed top plate as the upper limiting component. The inner side of the inner upper annular fixed top plate is closely attached to the outer side of the transmission chassis and fixedly installed at a certain height above the rotating chassis, forming the first shearing box on the rotating chassis, thus forming an annular first receiving groove. The second movable element constituting the second shear box includes only an outer upper annular fixed top plate. The outer upper annular fixed top plate serves as an upper limit, and its inner side is closely attached to the outer side of the inner upper annular fixed top plate. It is fixedly installed at a certain height above the fixed base, forming the second shear box on the fixed base, thus forming an annular second receiving groove. The second shear box is fixed to the base plate by the fixed base. The opening of the second receiving groove communicates with the opening of the first receiving groove to form an annular receiving cavity for accommodating the test sample.

5. The circumferential shear test device for a circular structure surface according to claim 4, characterized in that, The installation height of the inner upper annular fixed top plate from the top of the rotating base and the installation height of the outer upper annular fixed top plate from the top of the fixed base are adjusted according to the thickness of the annular sample to accommodate annular samples of different thicknesses.

6. The circular shear test apparatus for a circular structural surface according to any one of claims 1-5, characterized in that, The normal pressure component includes a pressure motor, a second drive shaft, a pressure plate, and a pressure sensor. The pressure sensor is connected to the pressure motor. The shape of the pressure plate can be adjusted according to the outer wall of the sheared sample. The pressure motor drives the second drive shaft to apply a load to the outer wall of the sample through the pressure plate.

7. The circular shear test apparatus for a circular structural surface according to any one of claims 1-5, characterized in that, The rotating guide rail component includes a support column, a slider, and a guide rail. One end of the support column is fixed to the slider, and the other end of the support column is connected to the normal pressure component. The guide rail is a circular guide rail, and the slider can slide in the guide rail, thereby driving the normal pressure component to rotate around the first transmission shaft, so as to apply different loads to different positions of the shear sample.

8. The circular shear test apparatus for a circular structural surface according to any one of claims 1-5, characterized in that, The servo motor applies circumferential shear force by means of a fixed angular velocity or a fixed torque.

9. A circumferential shear test method using the circumferential shear test apparatus for any of claims 1-8, characterized in that, Specifically, the steps include the following: S1. According to the shape of the sample to be tested, select the appropriate first movable element and second movable element, and install them in the corresponding installation positions on the rotating chassis and the fixed chassis to form the first shear box and the second shear box. Fix the sample to be tested in the first shear box and the second shear box. The contact surface between the internal material A in the first shear box and the external material B in the second shear box is the shear surface. S2. Adjust the rotating guide rail component so that the normal pressure component and the test sample are in the same sector area and their center planes are on the same horizontal plane, and make the pressure direction of the normal pressure component point to the axis of the first drive shaft of the servo motor to ensure strict normal load application. S3. Start the pressure motor of the normal pressure component, so that the pressure plate is lightly attached to the outer wall of the test sample, and apply a suitable normal load; S4. Start the servo motor and rotate the chassis, which serves as the bottom component of the first shear box. Driven by the first transmission shaft, the first shear box rotates relative to the second shear box to perform circumferential shearing on the sample using a suitable loading method. S5. When the sample is sheared in the circumferential direction, the resistance it experiences is transmitted sequentially through the rotating base, transmission base, connecting column, and torsion transmission disk to the lower flange of the dual flange torque sensor. The lower flange and the upper flange are subjected to relative torsion. The dual flange torque sensor measures the real-time torque, and the pressure sensor in the normal pressure component obtains the real-time normal load. S6. By measuring the forces under different parameter conditions, the effects of the specimen thickness, radius, central angle, material type, load magnitude and location, and shear surface radius on the circumferential shear mechanical properties of the circular structure can be experimentally determined.

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