Large-scale triaxial dynamic geotechnical shear test system and test method

Abstract

The present invention relates to a large-scale triaxial dynamic geotechnical shear test system and a test method. The large-scale triaxial dynamic geotechnical shear test system comprises a four-column loading frame, a shear box, a z-axis servo cylinder, a x-axis servo cylinder, a y-axis servo cylinder, a specimen transport system, a hydraulic system, a cooling system, a data collection system, a computer control system, and a computer control cabinet; the shear box can be transported into the four-column loading frame by means of the specimen transport system; the computer control system is electrically connected to the computer control cabinet; and the hydraulic system, the cooling system, and the data collection system are all electrically connected to the computer control system. The present invention has the beneficial effect of enabling a triaxial direct shear, triaxial simple shear, or triaxial cyclic shear test on rock and soil masses under conditions of constant normal load, constant normal stiffness, and dynamic normal load, allowing the study of the influence of multi-directional characteristics of seismic motion on dynamic properties of rocks, facilitating revelation of the mechanism of slope dynamic instability.

Description

Large three-dimensional dynamic rock-soil integrated shear test system and test method TECHNICAL FIELD

[0001] The present application relates to the technical field of rock-soil mechanics test, in particular to a large three-dimensional dynamic rock-soil integrated shear test system and test method. BACKGROUND

[0002] Rock-soil bodies widely exist in nature, which are the general term of rocks and soils. They can be transformed into each other under the conditions of geological action, climate, biological action and human engineering activities, but their mechanical properties are quite different. Engineering geological problems are mostly related to the mechanical parameter values of fractured rock mass and soil-rock mixture. In actual engineering, the strength of rock-soil bodies is crucial to engineering safety, especially in the southwest region of China where strong earthquakes occur frequently, which is located between the Pacific earthquake belt and the Himalaya-Mediterranean earthquake belt, and is one of the most active regions of geological structure on the global continent. Rock-soil bodies suffer cumulative loss under external forces such as earthquakes, which is one of the important inducements for the instability of slope and tunnel engineering.

[0003] Seismic load has dynamic characteristics and cyclic properties. Dynamic characteristics are reflected in the influence of load amplitude, frequency and loading rate on rock-soil bodies under shear, and cyclic properties are reflected in the degradation of rock-soil shear strength parameters under cyclic shear load. For near-field strong earthquakes, seismic load has multi-directionality, that is, there are differences in the influence of earthquakes on different directions of the same data monitoring point. Under the influence of seismic load, the slope rock mass or tunnel engineering along the weak surface will be dislocated and slipped, and finally unstable. The shear test device is the key equipment for exploring the shear mechanical properties, failure mechanism and instability and sliding mechanism of rock-soil bodies. The current shear test system mostly has the problems of insufficient load loading range, boundary conditions and the functions of the corresponding shear box. Specifically, it cannot meet the loading power of large sample shear, cannot simulate three-dimensional dynamic characteristics, and cannot simultaneously satisfy the shear of rock mass and soil-rock mixture samples.

[0004] However, due to the functional limitations of rock-soil mechanics test equipment, the research on the strength attenuation law and dynamic characteristics of rock-soil bodies under seismic load needs to be further deepened. Therefore, it is necessary to develop a large three-dimensional dynamic rock-soil integrated shear test system (LVDDCS-R / S) which can realize the above functions. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art, and provides a large three-dimensional dynamic rock-soil integrated shear test system and a test method, which can realize three-dimensional direct shear, three-dimensional simple shear or three-dimensional cyclic shear test of rock-soil under the conditions of constant normal load, constant normal stiffness and dynamic normal load, and can realize normal and tangential self-defined waveform (including pulse load) loading, thereby studying the influence of seismic motion multidirectionality on the dynamic characteristics of rock, and helping to reveal the dynamic instability mechanism of slope.

[0006] The present application aims to overcome the shortcomings of the prior art, and provides a large three-dimensional dynamic rock-soil integrated shear test system and a test method, which can realize three-dimensional direct shear, three-dimensional simple shear or three-dimensional cyclic shear test of rock-soil under the conditions of constant normal load, constant normal stiffness and dynamic normal load, and can realize normal and tangential self-defined waveform (including pulse load) loading, thereby studying the influence of seismic motion multidirectionality on the dynamic characteristics of rock, and helping to reveal the dynamic instability mechanism of slope.

[0007] The present application provides a large three-dimensional dynamic rock-soil integrated shear test system, which comprises a four-column loading frame, a shear box, a z-direction servo cylinder, an x-direction servo cylinder, a y-direction servo cylinder, a sample transportation system, a hydraulic system, a cooling system, a data acquisition system, a computer control system and a computer control cabinet; the shear box is arranged in the four-column loading frame, the z-direction servo cylinder is arranged at the top of the four-column loading frame and acts on the shear box through a z-direction pressure head, the x-direction servo cylinder and the y-direction servo cylinder are arranged on the side wall of the four-column loading frame and act on the shear box horizontally, one side of the four-column loading frame is provided with an opening, the sample transportation system is arranged at the opening, the shear box can be transported into the four-column loading frame through the sample transportation system, and the shear box is a simple shear box or a direct shear box; the hydraulic system is used for supplying hydraulic oil to the z-direction servo cylinder, the x-direction servo cylinder and the y-direction servo cylinder, and the cooling system is used for cooling the hydraulic oil supplied by the hydraulic system; the data acquisition system is used for measuring and collecting the loading parameters of the z-direction servo cylinder, the x-direction servo cylinder and the y-direction servo cylinder; the computer control system is electrically connected to the computer control cabinet, and the hydraulic system, the cooling system and the data acquisition system are electrically connected to the computer control system.

[0008] Further, the sample transportation system comprises a linear guide rail, a triangular support frame, a fastening cap, a counterforce pull rod, a tray, an antifriction ball strip and an x-direction antifriction roller, the linear guide rail is fixed to the opening of the four-column loading frame through the triangular support frame, the tray is slidingly arranged on the linear guide rail, the tray is provided with the counterforce pull rod on one side, the counterforce pull rod penetrates through the side wall of the four-column loading frame opposite to the opening and is connected to the fastening cap, the fastening cap abuts against the outer side wall of the four-column loading frame, a groove is formed in the top surface of the tray along the working direction of the x-direction servo cylinder, the x-direction antifriction roller is rollingly arranged at the bottom of the groove, the shear box can be arranged in the groove and supported on the x-direction antifriction roller, the antifriction ball strip is rollingly arranged on the side wall of the groove and can rollingly contact the shear box, and the side wall of the tray is provided with a stopper which can abut against the x-direction antifriction roller.

[0009] Further, the single shear shear box comprises a base, a stacked ring upper shear box, a guide column, a y-direction antifriction roller row, a shear pressure head, an acoustic emission stacked ring, a common stacked ring, an x-direction counterforce backing plate, an x-direction counterforce backup cap, a stacked ring lower shear box, a y-direction counterforce backup cap, a connecting backup cap, a y-direction counterforce backing plate, the stacked ring lower shear box is arranged on the base, the common stacked ring is arranged on the top of the stacked ring lower shear box, the acoustic emission stacked ring is arranged on the top of the common stacked ring, the stacked ring upper shear box is arranged on the top of the acoustic emission stacked ring, the shear pressure head is arranged on the top of the stacked ring upper shear box, the y-direction antifriction roller row is arranged on the top of the shear pressure head in a rolling manner, the z-direction pressure head is supported on the y-direction antifriction roller row, the loading end of the z-direction servo cylinder is abutted against the z-direction pressure head, the guide column is detachably arranged on the stacked ring upper shear box and is downwardly inserted into the stacked ring lower shear box, the acoustic emission stacked ring and the common stacked ring are sleeved on the guide column, the x-direction counterforce backing plate is arranged on the side wall of the stacked ring lower shear box, the x-direction counterforce backup cap is arranged on the x-direction counterforce backing plate, the loading end of the x-direction servo cylinder is abutted against the x-direction counterforce backup cap, the y-direction counterforce backing plate is arranged on the side wall of the stacked ring upper shear box, the y-direction counterforce backup cap is arranged on the y-direction counterforce backing plate through the connecting backup cap, and the loading end of the y-direction servo cylinder is abutted against the y-direction counterforce backup cap.

[0010] Further, the straight shear shear box comprises a base, a y-direction antifriction roller row, a shear pressure head, an x-direction counterforce backing plate, an x-direction counterforce backup cap, a y-direction counterforce backup cap, a connecting backup cap, a y-direction counterforce backing plate, a straight shear upper shear box and a straight shear lower shear box, the straight shear lower shear box is arranged on the base, the straight shear upper shear box is arranged on the top of the straight shear lower shear box, the shear pressure head is arranged on the top of the straight shear upper shear box, the y-direction antifriction roller row is arranged on the top of the shear pressure head in a rolling manner, the z-direction pressure head is supported on the y-direction antifriction roller row, the loading end of the z-direction servo cylinder is abutted against the z-direction pressure head, the x-direction counterforce backing plate is arranged on the side wall of the straight shear lower shear box, the x-direction counterforce backup cap is arranged on the x-direction counterforce backing plate, the loading end of the x-direction servo cylinder is abutted against the x-direction counterforce backup cap, the y-direction counterforce backing plate is arranged on the side wall of the straight shear upper shear box, the y-direction counterforce backup cap is arranged on the y-direction counterforce backing plate through the connecting backup cap, and the loading end of the y-direction servo cylinder is abutted against the y-direction counterforce backup cap.

[0011] Further, the base can be arranged in the groove and supported on the x-direction antifriction roller row, and the antifriction ball strip can be in rolling contact with the side wall of the base.

[0012] Further, the straight shear shear box is internally provided with a shearing assembly, the shearing assembly comprises a plurality of integrated shear boxes with different sizes, the plurality of integrated shear boxes are sequentially sleeved together from small to large in size, a sample is placed in the shearing assembly, a vertical antifriction assembly is arranged between the periphery of the shearing assembly and the straight shear shear box, the vertical antifriction assembly comprises a vertical antifriction roller row and an antifriction plate, the vertical antifriction roller row is located between the shearing assembly and the antifriction plate, the vertical antifriction roller row is abutted against the shearing assembly and the antifriction plate, the antifriction plate is abutted against the inner wall of the straight shear upper shear box, and a reserved acoustic emission hole is arranged on the antifriction plate.

[0013] Further, the data acquisition system comprises a z-direction magnetostrictive displacement sensor, an x-direction magnetostrictive displacement sensor, a y-direction magnetostrictive displacement sensor, a z-direction shear plate load sensor, an x-direction Folen sensor, a y-direction Folen sensor, the z-direction magnetostrictive displacement sensor, the x-direction magnetostrictive displacement sensor and the y-direction magnetostrictive displacement sensor are respectively arranged on the cylinder end face of the z-direction servo cylinder, the cylinder end face of the x-direction servo cylinder and the cylinder end face of the y-direction servo cylinder, one end of the z-direction shear plate load sensor is connected to the loading end of the z-direction servo cylinder through a load sensor cap, the other end of the z-direction shear plate load sensor is abutted to the z-direction pressure head through a ball head compression plate, the x-direction Folen sensor is arranged on the loading end of the x-direction servo cylinder and abutted to the x-direction counterforce cap, and the y-direction Folen sensor is arranged on the loading end of the y-direction servo cylinder and abutted to the y-direction counterforce cap.

[0014] Further, the top of the four-column loading frame is provided with a connecting seat, the cylinder of the z-direction servo cylinder is connected to the connecting seat through a heightening flange, the sidewall of the four-column loading frame is provided with an x-direction Folen sensor connecting hole and a y-direction Folen sensor connecting hole, the cylinder of the x-direction servo cylinder is arranged at the x-direction Folen sensor connecting hole through a connecting flange, the loading end of the x-direction servo cylinder passes through the x-direction Folen sensor connecting hole and is connected to the x-direction Folen sensor, the cylinder of the y-direction servo cylinder is arranged at the y-direction Folen sensor connecting hole through a connecting flange, the loading end of the y-direction servo cylinder passes through the y-direction Folen sensor connecting hole and is connected to the y-direction Folen sensor, and the top of the four-column loading frame is further provided with a lifting ring.

[0015] Further, based on the large three-direction dynamic rock-soil integrated shear test system, the application further provides a shear test method, which comprises the following steps:

[0016] S1, turn on the machine and check whether all the devices and instruments are normal.

[0017] S2, according to the type and size of the sample, select a shear box of a corresponding type and size, place the shear box on the x-direction antifriction roller row in the sample transportation system, and then put the sample into the shear box.

[0018] S3, transport the shear box to the position directly below the z-direction pressure head through the sample transportation system, make the counterforce pull rod pass through the sidewall of the four-column loading frame, and then tighten the fastening cap.

[0019] S4, apply a preset normal pressure to the shear box through the z-direction servo cylinder, then apply an initial tangential pressure to the shear box through the x-direction servo cylinder and the y-direction servo cylinder respectively, and finally perform different types of shear tests on the sample under the conditions of constant normal load, dynamic normal load or constant normal stiffness through the z-direction servo cylinder, the x-direction servo cylinder and the y-direction servo cylinder until the sample reaches a preset shear displacement or deformation, and in the test process, the data acquisition system collects the loading parameters of the z-direction servo cylinder, the x-direction servo cylinder and the y-direction servo cylinder.

[0020] S5, when the sample reaches the preset shear displacement or deformation, automatic stop and save test data, computer control system processes and analyzes the data collected by the data acquisition system.

[0021] Further, the shear test includes three types of three-way single shear test, three-way direct shear test and three-way cyclic shear test.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] The present application can realize three-way single shear, three-way direct shear and three-way cyclic shear test of rock and soil samples under the conditions of constant normal load, dynamic normal load and constant normal stiffness. The three-way cyclic shear test can realize multi-directional dynamic loading shear in the horizontal and vertical directions, and can also realize strain rate and multi-frequency loading under the action of seismic load (including pulse load). The large three-way dynamic rock-soil integrated shear test system of the present application can be used to study the influence of seismic multi-directionality on the dynamic characteristics of rock, which is beneficial to reveal the dynamic instability mechanism of slope and has important significance for the theoretical research and engineering design of rock and soil. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a schematic diagram of the operation principle of the large three-way dynamic rock-soil integrated shear test system of the present application;

[0025] Fig. 2 is a schematic diagram of the shear test loading structure of the shear box of the present application;

[0026] Fig. 3 is a schematic diagram of the structure of the four-column loading frame of the main machine of the present application;

[0027] Fig. 4 is a schematic diagram of the structure of the sample transportation system of the present application;

[0028] Fig. 5 is a schematic diagram of the overall structure of the single shear shear box of the present application;

[0029] Fig. 6 is a schematic diagram of the overall structure of the direct shear shear box of the present application;

[0030] Fig. 7 is a schematic diagram of the structure of the vertical friction reduction assembly of the present application;

[0031] Fig. 8 is a schematic diagram of the three-way direct shear test data results of the present application;

[0032] Fig. 9 is a schematic diagram of the three-way cyclic shear test data results of the present application.

[0033] In the figure: 1, computer control cabinet; 2, computer control system; 3, hydraulic system; 4, cooling system; 5, z-direction dynamic loading assembly; 6, x-direction dynamic loading assembly; 7, y-direction dynamic loading assembly; 8, single shear shear box; 9, straight shear shear box; 10, z-direction magnetostrictive displacement sensor; 11, z-direction servo cylinder; 12, high flange; 13, load sensor backup cap; 14, z-direction shear plate type load sensor; 15, ball head compression plate; 16, z-direction pressure head; 17, shear box; 18, x-direction Follen sensor; 19, x-direction servo cylinder; 20, x-direction magnetostrictive displacement sensor; 21, base; 22, y-direction magnetostrictive displacement sensor; 23, y-direction servo cylinder; 24, y-direction Follen sensor; 25, four-column loading frame; 26, connecting seat; 27, lifting ring; 28, column; 29, linear guide rail; 30, x-direction Follen sensor connecting hole; 31, triangular support frame; 32, fastening backup cap; 33, y-direction Follen sensor connecting hole; 34, tray; 35, antifriction ball bar; 36, x-direction antifriction roller; 37, stop block; 38, upper shear box of stacked ring; 39, guide column; 40, y-direction antifriction roller; 41, shear pressure head; 42, z-direction deformation sensor through hole; 43, acoustic emission stacked ring; 44, ordinary stacked ring; 45, x-direction counterforce backing plate; 46, x-direction counterforce backup cap; 47, lower shear box of stacked ring; 48, y-direction counterforce backup cap; 49, connecting backup cap; 50, y-direction counterforce backing plate; 51, antifriction plate; 52, vertical antifriction roller; 53, upper shear box of straight shear; 54, reserved acoustic emission hole; 55, lower shear box of straight shear. DETAILED DESCRIPTION

[0034] The application will be further described below in conjunction with the drawings, but the protection scope of the application is not limited to the following description.

[0035] As shown in FIGS. 1-7, a large three-direction dynamic rock-soil integrated shear test system includes a four-column loading frame 25, a shear box 17, a z-direction servo cylinder 11, an x-direction servo cylinder 19, a y-direction servo cylinder 23, a sample transportation system, a hydraulic system 3, a cooling system 4, a data acquisition system, a computer control system 2 and a computer control cabinet 1.

[0036] The four-column loading frame 25 is provided with an opening on one side, and the sample transportation system is installed at the opening, and the shear box 17 can be transported into the four-column loading frame 25 through the sample transportation system. The z-direction servo cylinder 11 is installed at the top of the four-column loading frame 25 and vertically acts on the shear box 17 through the z-direction pressure head 16, and the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are installed on the side wall of the four-column loading frame 25 and horizontally act on the shear box 17.

[0037] The shear box 17 is a single shear shear box 8 or a straight shear shear box 9, according to the type and size of the sample, the corresponding shear box 17 is selected, then the sample is placed in the shear box 17, the hydraulic system 3 provides hydraulic oil to the z-direction servo cylinder 11, the x-direction servo cylinder 19 and the y-direction servo cylinder 23, controls the z-direction servo cylinder 11 to load the normal pressure on the shear box 17, controls the x-direction servo cylinder 19 and the y-direction servo cylinder 23 to load the tangential pressure on the shear box 17, and then the sample is subjected to a shear test. During the test, the cooling system 4 is used to cool the hydraulic oil provided by the hydraulic system 3 to prevent the oil temperature from rising rapidly during dynamic shear, which affects the normal operation of the equipment; the data acquisition system is used to measure and collect the loading parameters of the z-direction servo cylinder 11, the x-direction servo cylinder 19 and the y-direction servo cylinder 23; the computer control system 2 is electrically connected to the computer control cabinet 1, the hydraulic system 3, the cooling system 4 and the data acquisition system are electrically connected to the computer control system 2, and then the computer control system 2 is used to control and adjust the hydraulic system 3, the cooling system 4 and the data acquisition system.

[0038] As shown in FIG. 4, the sample transportation system includes a linear guide rail 29, a triangular support frame 31, a fastening cap 32, a counterforce pull rod, a tray 34, an antifriction ball strip 35 and an x-direction antifriction roller 36. The linear guide rail 29 is fixed and supported on the opening of the four-column loading frame 25 through the triangular support frame 31, the tray 34 is slidably arranged on the linear guide rail 29, the counterforce pull rod is fixed on one side of the tray 34 and penetrates through the side wall of the four-column loading frame 25 opposite to the opening and is connected to the fastening cap 32, the fastening cap 32 abuts against the outer side wall of the four-column loading frame 25, a groove is formed in the top surface of the tray 34 along the working direction of the x-direction servo cylinder 19, the x-direction antifriction roller 36 is rollingly installed at the bottom of the groove, and the antifriction ball strip 35 is rollingly installed on the side wall of the groove. The shear box 17 is placed in the groove and supported on the x-direction antifriction roller 36, then the shear box 17 can be transported into the four-column loading frame 25 by sliding the tray 34 on the linear guide rail 29, when the shear box 17 is transported to the position directly below the z-direction pressure head 16, the counterforce pull rod penetrates through the side wall of the four-column loading frame 25, then the fastening cap 32 is tightened to fix the tray 34, when the shear box 17 is placed in the groove, the antifriction ball strip 35 can rollingly contact with the shear box 17, through the arrangement of the x-direction antifriction roller 36 and the antifriction ball strip 35, the friction between the shear box 17 and the tray 34 during the shear test can be reduced, and then the accuracy of the test result is improved. In addition, a stopper 37 is fixed on the side wall of the tray 34, during the shear test, the x-direction antifriction roller 36 is forced to roll to abut against the stopper 37, then the stopper 37 can stop the x-direction antifriction roller 36, preventing the x-direction antifriction roller 36 from being taken out of the tray 34 due to shear.

[0039] As shown in Fig. 5, the single-shear shear box 8 comprises a base 21, a stack ring upper shear box 38, a guide column 39, a y-direction friction-reducing roller row 40, a shear pressure head 41, an acoustic emission stack ring 43, a common stack ring 44, an x-direction counterforce backing plate 45, an x-direction counterforce backup cap 46, a stack ring lower shear box 47, a y-direction counterforce backup cap 48, a connecting backup cap 49, and a y-direction counterforce backing plate 50. The stack ring lower shear box 47 is placed on the base 21, the common stack ring 44 is arranged on the top of the stack ring lower shear box 47, the acoustic emission stack ring 43 is arranged on the top of the common stack ring 44, the stack ring upper shear box 38 is arranged on the top of the acoustic emission stack ring 43, the shear pressure head 41 is arranged on the top of the stack ring upper shear box 38, and the y-direction friction-reducing roller row 40 is rollingly arranged on the top of the shear pressure head 41. The z-direction pressure head 16 is supported on the y-direction friction-reducing roller row 40, the loading end of the z-direction servo cylinder 11 abuts against the z-direction pressure head 16, and thus the z-direction pressure head 16 can be used to apply a normal pressure to the shear box 17. The guide column 39 is detachably arranged on the stack ring upper shear box 38 and downwardly inserted into the stack ring lower shear box 47, and the acoustic emission stack ring 43 and the common stack ring 44 are sleeved on the guide column 39. The x-direction counterforce backing plate 45 is fixed on the side wall of the stack ring lower shear box 47, the x-direction counterforce backup cap 46 is directly fixed on the x-direction counterforce backing plate 45 by means of screws, the loading end of the x-direction servo cylinder 19 abuts against the x-direction counterforce backup cap 46, and thus the x-direction counterforce backup cap 46 and the x-direction counterforce backing plate 45 can be used to apply an x-direction tangential pressure to the shear box 17. The y-direction counterforce backing plate 50 is fixed on the side wall of the stack ring upper shear box 38, the y-direction counterforce backup cap 48 is fixed on the y-direction counterforce backing plate 50 by means of the connecting backup cap 49, the loading end of the y-direction servo cylinder 23 abuts against the y-direction counterforce backup cap 48, and thus the y-direction counterforce backup cap 48 and the y-direction counterforce backing plate 50 can be used to apply a y-direction tangential pressure to the shear box 17. In addition, the z-direction deformation sensor passing hole 42 is reserved in the stack ring upper shear box 38, and an LVDT deformation sensor can be arranged in the z-direction deformation sensor passing hole 42 to make the LVDT deformation sensor directly contact with the z-direction pressure head 16. The LVDT deformation sensor is an additional accessory, and can be added as needed according to actual test conditions.

[0040] In the present embodiment, the acoustic emission stack ring 43 and the common stack ring 44 in the single-shear shear box 8 can be selected as square stack rings or circular stack rings. The square stack rings include four size specifications of 100 mm x 100 mm, 150 mm x 150 mm, 200 mm x 200 mm, and 300 mm x 300 mm, and the circular stack rings include four size specifications of φ100 mm x 100 mm, φ150 mm x 150 mm, φ200 mm x 200 mm, and φ300 mm x 300 mm.

[0041] As shown in Figure 6, the direct shear shear box 9 includes a base 21, a y-direction friction reduction roller row 40, a shear pressure head 41, an x-direction counterforce backing plate 45, an x-direction counterforce backup cap 46, a y-direction counterforce backup cap 48, a connecting backup cap 49, a y-direction counterforce backing plate 50, a direct shear upper shear box 53, and a direct shear lower shear box 55. The direct shear lower shear box 55 is placed on the base 21, the direct shear upper shear box 53 is arranged on the top of the direct shear lower shear box 55, the shear pressure head 41 is placed on the top of the direct shear upper shear box 53, the y-direction friction reduction roller row 40 is rollingly arranged on the top of the shear pressure head 41, the z-direction pressure head 16 is supported on the y-direction friction reduction roller row 40, the loading end of the z-direction servo cylinder 11 abuts against the z-direction pressure head 16, and thus the z-direction pressure head 16 can be used to apply a normal pressure to the shear box 17. The x-direction counterforce backing plate 45 is fixed on the side wall of the direct shear lower shear box 55, the x-direction counterforce backup cap 46 is directly fixed on the x-direction counterforce backing plate 45 by means of screws, the loading end of the x-direction servo cylinder 19 abuts against the x-direction counterforce backup cap 46, and thus the x-direction counterforce backup cap 46 and the x-direction counterforce backing plate 45 can be used to apply an x-direction tangential pressure to the shear box 17. The y-direction counterforce backing plate 50 is fixed on the side wall of the direct shear upper shear box 53, the y-direction counterforce backup cap 48 is fixed on the y-direction counterforce backing plate 50 by means of the connecting backup cap 49, the loading end of the y-direction servo cylinder 23 abuts against the y-direction counterforce backup cap 48, and thus the y-direction counterforce backup cap 48 and the y-direction counterforce backing plate 50 can be used to apply a y-direction tangential pressure to the shear box 17.

[0042] The direct shear shear box 9 is provided with a shear assembly, which includes a plurality of integrated shear boxes with different sizes. In the embodiment, the integrated shear boxes are in the shape of a square or a cylinder. The square-shaped integrated shear boxes include four size specifications, i.e., 100 mm x 100 mm, 150 mm x 150 mm, 200 mm x 200 mm, and 300 mm x 300 mm. The cylindrical-shaped integrated shear boxes include four size specifications, i.e., φ100 mm x 100 mm, φ150 mm x 150 mm, φ200 mm x 200 mm, and φ300 mm x 300 mm. During a test, a plurality of integrated shear boxes with the same shape are sequentially sleeved together according to the size from small to large to form a shear assembly. After the shear assembly is placed in the direct shear shear box 9, a sample is placed in the shear assembly, and thus the direct shear test of a square sample and a cylindrical sample can be realized. As shown in Figures 6 and 7, a vertical friction reduction assembly is arranged between the shear assembly and the direct shear shear box 9. The vertical friction reduction assembly includes a vertical friction reduction roller row 52 and a friction reduction plate 51. The vertical friction reduction roller row 52 is located between the shear assembly and the friction reduction plate 51, and abuts against the shear assembly and the friction reduction plate 51. The friction reduction plate 51 abuts against the inner wall of the direct shear upper shear box 53. The vertical friction reduction roller row 52 is used to reduce the contact friction between the shear assembly and the direct shear upper shear box 53 during a test, and the friction reduction plate 51 is used to reduce the gap between the direct shear upper shear box 53 and the shear assembly. The friction reduction plate 51 is provided with a reserved acoustic emission hole, which can be used for acoustic emission test.

[0043] Regardless of the single shear shear box 8 or straight shear shear box 9, when the shear box 17 is placed on the tray 34, the base 21 is located in the groove and supported on the x-direction antifriction roller row 36, and the antifriction ball bar 35 is in rolling contact with the sidewall of the base 21.

[0044] As shown in FIG. 2, the data acquisition system includes a z-direction magnetostrictive displacement sensor 10, an x-direction magnetostrictive displacement sensor 20, a y-direction magnetostrictive displacement sensor 22, a z-direction shear plate load sensor 14, an x-direction Follan sensor 18, and a y-direction Follan sensor 24. The z-direction magnetostrictive displacement sensor 10, the x-direction magnetostrictive displacement sensor 20, and the y-direction magnetostrictive displacement sensor 22 are respectively arranged at the cylinder end face of the z-direction servo cylinder 11, the cylinder end face of the x-direction servo cylinder 19, and the cylinder end face of the y-direction servo cylinder 23, and are respectively used to acquire the loading displacement of the z-direction servo cylinder 11, the x-direction servo cylinder 19, and the y-direction servo cylinder 23; one end of the z-direction shear plate load sensor 14 is connected to the loading end of the z-direction servo cylinder 11 through a load sensor backup cap 13, and the other end of the z-direction shear plate load sensor 14 is connected with a ball head compression plate 15, which in turn abuts against a z-direction pressure head 16, and the normal load applied by the z-direction servo cylinder 11 can be acquired through the z-direction shear plate load sensor 14; the x-direction Follan sensor 18 is arranged at the loading end of the x-direction servo cylinder 19 and abuts against an x-direction counterforce backup cap 46, and the tangential load applied by the x-direction servo cylinder 19 can be acquired through the x-direction Follan sensor 18; the y-direction Follan sensor 24 is arranged at the loading end of the y-direction servo cylinder 23 and abuts against a y-direction counterforce backup cap 48, and the tangential load applied by the y-direction servo cylinder 23 can be acquired through the y-direction Follan sensor 24.

[0045] In the embodiment, the range of the z-direction magnetostrictive displacement sensor 10, the x-direction magnetostrictive displacement sensor 20, and the y-direction magnetostrictive displacement sensor 22 is 130 mm, and the measurement accuracy is 0.5% F.S. The data sampling frequency of the normal and tangential loads and displacements can be changed in the range of 0-1000 Hz; the range of the z-direction shear plate load sensor 14 is 2000 kN, and the measurement accuracy is 0.5% F.S; the maximum range of the x-direction Follan sensor 18 and the y-direction Follan sensor 24 is 1500 KN, and the measurement accuracy is 0.5% F.S.

[0046] As shown in Fig. 3, the four-column loading frame 25 is connected and supported by four columns 28, a connecting seat 26 is fixed on the top of the four-column loading frame 25, a heightening flange 12 is fixed on the cylinder barrel of the z-direction servo cylinder 11, the heightening flange 12 is connected to the connecting seat 26 by screws, the loading end of the z-direction servo cylinder 11 is inserted into the four-column loading frame 25 through the connecting seat 26; the x-direction Follin sensor 18 connecting hole and the y-direction Follin sensor 24 connecting hole are arranged on the side wall of the four-column loading frame 25, the connecting flange is fixed on the cylinder barrel of the x-direction servo cylinder 19 and the y-direction servo cylinder 23, the connecting flange on the x-direction servo cylinder 19 is fixed in the x-direction Follin sensor 18 connecting hole by screws, then the x-direction servo cylinder 19 is installed on the four-column loading frame 25, the loading end of the x-direction servo cylinder 19 is inserted into the x-direction Follin sensor 18 connecting hole and connected to the x-direction Follin sensor 18; the connecting flange on the y-direction servo cylinder 23 is fixed in the y-direction Follin sensor 24 connecting hole by screws, then the y-direction servo cylinder 23 is installed on the four-column loading frame 25, the loading end of the y-direction servo cylinder 23 is inserted into the y-direction Follin sensor 24 connecting hole and connected to the y-direction Follin sensor 24. The hoisting ring 27 is arranged on the top of the four-column loading frame 25, which is convenient for hoisting the four-column loading frame 25.

[0047] As shown in FIG. 1, FIG. 2, in the embodiment, the z-direction servo cylinder 11, the z-direction magnetostrictive displacement sensor 10 and the z-direction shear plate load sensor 14 constitute a z-direction dynamic loading assembly 5, the x-direction servo cylinder 19, the x-direction magnetostrictive displacement sensor 20 and the x-direction Follin sensor 18 constitute an x-direction dynamic loading assembly 6, and the y-direction servo cylinder 23, the y-direction magnetostrictive displacement sensor 22 and the y-direction Follin sensor 24 constitute a y-direction dynamic loading assembly 7; the computer control cabinet 1, the computer control system 2, the hydraulic system 3, the z-direction dynamic loading assembly 5, the x-direction dynamic loading assembly 6, the y-direction dynamic loading assembly 7, the z-direction magnetostrictive displacement sensor 10, the x-direction magnetostrictive displacement sensor 20, the y-direction magnetostrictive displacement sensor 22, the z-direction shear plate load sensor 14, the x-direction Follin sensor 18 and the y-direction Follin sensor 24 are matched with the added controller and servo valve to jointly constitute a servo control system. The control principle of the servo control system is as follows: the computer control system 2 issues instructions to the controller through Ethernet, the controller transmits the instructions to the servo valve through PID servo control, the size of the opening of the servo valve determines the size of the force borne by the shear box 17, then the z-direction shear plate load sensor 14, the x-direction Follin sensor 18 and the y-direction Follin sensor 24 convert the electrical signals into load sizes and transmit them to the controller, and the controller feeds back the signals to the computer control system 2. Similarly, the z-direction magnetostrictive displacement sensor 10, the x-direction magnetostrictive displacement sensor 20 and the y-direction magnetostrictive displacement sensor 22 feed back the displacement of the oil cylinder piston to the controller, and the controller feeds back the signals to the computer control system 2. Through the servo control system, the test device can realize three-way straight shear, three-way single shear and three-way cyclic shear tests under the conditions of constant normal load, constant normal stiffness and dynamic normal load, as well as closed-loop control of normal and tangential self-defined waveforms (including pulse load).

[0048] The hydraulic system 3 is of an existing structure and mainly consists of an oil tank, four oil pumps (motor groups), a precision oil filter, an overflow valve, a pressure gauge, an air filter, a bladder accumulator and a pipeline. Since the static loading oil cylinder and the dynamic loading actuator have different requirements for the flow rate and working pressure of hydraulic oil during execution, in order to accurately control the oil cylinder, different oil pumps are used for driving the static loading and the dynamic loading, two oil pumps drive the z-direction servo cylinder 11, and the other two oil pumps respectively drive the x-direction servo cylinder 19 and the y-direction servo cylinder 23. The bladder accumulator is used to improve the instantaneous flow rate of the servo cylinder to realize rapid and dynamic disturbance shear. The volume of the oil tank is 1000L, and a liquid level meter is arranged on the oil tank to observe the remaining amount of hydraulic oil at any time so as to supply in time.

[0049] When the above large three-way dynamic rock-soil integrated shear test system is used to perform a shear test, the following steps are included:

[0050] S1, turn on the power and check whether each device and instrument is normal.

[0051] S2, select a corresponding type and size of the shear box 17 according to the sample type and size, place the shear box 17 on the x-direction antifriction roller array 36 in the sample transportation system, and then put the sample into the shear box 17.

[0052] S3, transport the shear box 17 to the z-direction pressure head 16 by the sample transportation system, pass the counterforce pull rod through the four-column loading frame 25 side wall, and then tighten the fastening cap 32.

[0053] S4, apply a preset normal pressure to the shear box 17 by the z-direction servo cylinder 11, and then apply an initial tangential pressure to the shear box 17 by the x-direction servo cylinder 19 and the y-direction servo cylinder 23 respectively, and finally perform different types of shear tests on the sample under the conditions of constant normal load, dynamic normal load or constant normal stiffness by the z-direction servo cylinder 11, the x-direction servo cylinder 19 and the y-direction servo cylinder 23 until the sample reaches a preset shear displacement or deformation, and the data acquisition system collects the loading parameters of the z-direction servo cylinder 11, the x-direction servo cylinder 19 and the y-direction servo cylinder 23 during the test. Specifically, the shear test includes three types of three-way simple shear test, three-way direct shear test and three-way cyclic shear test.

[0054] S5, when the sample reaches the preset shear displacement or deformation, automatically stop and save the test data, and the computer control system 2 processes and analyzes the data collected by the data acquisition system.

[0055] During the test, the sample can be selected as a rock mass or a soil-rock mixture. In this embodiment, when the rock mass is subjected to a simple shear test, a simple shear shear box 8 is selected for the test. During sample loading, the base 21 is placed on the x-direction antifriction roller array 36, then the stacked ring lower shear box 47 is placed on the base 21, the rock mass sample is placed in the stacked ring lower shear box 47, then the four guide columns 39 are inserted into the stacked ring upper shear box 38 and then inserted into the stacked ring lower shear box 47, at the same time, the ordinary stacked ring 44 and the acoustic emission stacked ring 43 are sequentially sleeved on the guide columns 39, so as to realize layering until a preset height is reached, and finally the stacked ring upper shear box 38 is placed on the top of the acoustic emission stacked ring 43, and the guide columns 39 are removed and then the shear pressure head 41 is placed. When the soil-rock mixture is subjected to a simple shear test, a simple shear shear box 8 is also selected for the test. During sample loading, the stacked ring upper shear box 38 is placed on the top of the acoustic emission stacked ring 43 according to the above sample loading process, the cylindrical rubber sleeve is placed in the stacked ring, the soil-rock mixture is layered and pressed in the rubber sleeve, then the opening of the rubber sleeve is sealed, and then the guide columns 39 are removed and the shear pressure head 41 is placed.

[0056] In the embodiment, when the direct shear test is performed on the rock mass, the direct shear shear box 9 is selected for the test. When the sample is loaded, the base 21 is placed on the x-direction friction-reducing roller row 36, the shear assembly is assembled and placed in the direct shear lower shear box 55, then the direct shear lower shear box 55 is placed on the base 21, then the rock mass sample is placed in the shear assembly, the direct shear upper shear box 53 is placed on the top of the direct shear lower shear box 55, the direct shear upper shear box 53 is sleeved on the shear assembly, and finally the vertical friction-reducing roller row 52 and the friction-reducing plate 51 are placed between the shear assembly and the direct shear upper shear box 53 in sequence, and the shear pressure head 41 is placed on the top of the direct shear upper shear box 53.

[0057] In the embodiment, when the triaxial simple shear or direct shear test is performed on the sample under the constant normal load, the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are used to apply the shear force to the sample according to the pre-input constant normal load value until the sample reaches the designed shear displacement or deformation; when the triaxial simple shear or direct shear test is performed on the sample under the dynamic normal load, the frequency and amplitude of the z-direction servo cylinder 11 are set according to the pre-input seismic wave transformation, and then the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are used to apply the dynamic shear force to the sample until the sample reaches the designed shear displacement or deformation; when the triaxial simple shear or direct shear test is performed on the sample under the constant normal stiffness, the constant normal stiffness test function built in the software is started, the initial normal stress σ0 and the constant normal stiffness coefficient Kn are input, and then the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are used to apply the shear force to the sample until the sample reaches the designed shear displacement or deformation. When the direct shear test is performed, the screw for connecting the x-direction reaction force backup cap 46 and the x-direction reaction force backing plate 45 and the connecting backup cap 49 can be disassembled.

[0058] In the embodiment, when the triaxial simple shear or direct shear test is performed on the sample under the constant normal load, the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are used to apply the shear force to the sample according to the pre-input constant normal load value until the sample reaches the designed shear displacement or deformation; when the triaxial simple shear or direct shear test is performed on the sample under the dynamic normal load, the frequency and amplitude of the z-direction servo cylinder 11 are set according to the pre-input seismic wave transformation, and then the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are used to apply the dynamic shear force to the sample until the sample reaches the designed shear displacement or deformation; when the triaxial simple shear or direct shear test is performed on the sample under the constant normal stiffness, the constant normal stiffness test function built in the software is started, the initial normal stress σ0 and the constant normal stiffness coefficient Kn are input, and then the x-direction servo cylinder 19 and the y-direction servo cylinder 23 are used to apply the shear force to the sample until the sample reaches the designed shear displacement or deformation. When the direct shear test is performed, the screw for connecting the x-direction reaction force backup cap 46 and the x-direction reaction force backing plate 45 and the connecting backup cap 49 can be disassembled.

[0059] The large three-way dynamic rock-soil integrated shearing test system is used to carry out actual shearing test, and three-way direct shearing test results as shown in Figure 8 and three-way cyclic shearing test results as shown in Figure 9 are obtained. According to the shearing displacement-shearing load change curve in the experimental results, it can be known that the three-way cyclic shearing test can realize two-way horizontal and vertical multi-directional dynamic loading shearing servo dynamic loading under the conditions of constant normal load, dynamic normal load and constant normal stiffness, and can also realize strain rate and multi-frequency segment loading under the action of seismic load (including pulse load). Therefore, the large three-way dynamic rock-soil integrated shearing test system can be used to study the influence of seismic multi-directionality on the dynamic characteristics of rock, is beneficial to reveal the dynamic instability mechanism of slope, and has important significance for the theoretical research and engineering design of rock-soil body.

[0060] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A large-scale triaxial dynamic soil-rock integration shearing test system comprising a four-column loading frame (25), characterized in that, Also include: Shear box (17), z servo cylinder (11), x servo cylinder (19), y servo cylinder (23) and sample transport system, shear box (17) is arranged in four column loading frame (25), z servo cylinder (11) is arranged in the top of four column loading frame (25) and is applied to shear box (17) by z vertical head (16), x servo cylinder (19) and y servo cylinder (23) are arranged in the side wall of four column loading frame (25) and are applied to shear box (17) horizontally, one side of four column loading frame (25) is provided with opening, sample transport system is arranged in opening, shear box (17) can be transported to four column loading frame (25) by sample transport system, shear box (17) is single shear shear box (8) or straight shear shear box (9). Hydraulic system (3) and cooling system (4), hydraulic system (3) is used to provide hydraulic oil to z servo cylinder (11), x servo cylinder (19), y servo cylinder (23), cooling system (4) is used to cool the hydraulic oil provided by hydraulic system (3); Data acquisition system, data acquisition system is used to measure and collect the loading parameters of z servo cylinder (11), x servo cylinder (19), y servo cylinder (23); Computer control system (2) and computer control cabinet (1), computer control system (2) is electrically connected to computer control cabinet (1), hydraulic system (3), cooling system (4), data acquisition system are electrically connected to computer control system (2); Straight shear shear box (9) includes base (21), y antifriction roll (40), shear head (41), x counterforce backing plate (45), x counterforce backup cap (46), y counterforce backup cap (48), connecting backup cap (49), y counterforce backing plate (50), straight shear upper shear box (53), straight shear lower shear box (55), straight shear lower shear box (55) is arranged on the base (21), straight shear upper shear box (53) is arranged on the top of straight shear lower shear box (55), shear head (41) is arranged on the top of straight shear upper shear box (53), y antifriction roll (40) is arranged on the top of shear head (41), z vertical head (16) is supported on y antifriction roll (40), the loading end of z servo cylinder (11) is abutted to z vertical head (16), x counterforce backing plate (45) is arranged on the side wall of straight shear lower shear box (55), x counterforce backup cap (46) is arranged on x counterforce backing plate (45), the loading end of x servo cylinder (19) is abutted to x counterforce backup cap (46), y counterforce backing plate (50) is arranged on the side wall of straight shear upper shear box (53), y counterforce backup cap (48) is arranged on y counterforce backing plate (50) through connecting backup cap (49), the loading end of y servo cylinder (23) is abutted to y counterforce backup cap (48); The direct shear shear box (9) is provided with a shear assembly, the shear assembly includes a plurality of integrated shear boxes with different sizes, the plurality of integrated shear boxes are sequentially sleeved together from small to large in size, a sample is placed in the shear assembly, a vertical friction reduction assembly is arranged between the shear assembly and the direct shear shear box (9) around, the vertical friction reduction assembly includes a vertical friction reduction roller row (52) and a friction reduction plate (51), the vertical friction reduction roller row (52) is located between the shear assembly and the friction reduction plate (51), the vertical friction reduction roller row (52) abuts against the shear assembly and the friction reduction plate (51), the friction reduction plate (51) abuts against the inner wall of the direct shear upper shear box (53), and the friction reduction plate (51) is provided with a reserved acoustic emission hole (54). 2.The large-scale triaxial dynamic geotechnical integrated shear test system according to claim 1, characterized in that: The sample transportation system includes a linear guide rail (29), a triangular support frame (31), a fastening cap (32), a counterforce pull rod, a tray (34), a friction reduction ball strip (35) and an x-direction friction reduction roller row (36), the linear guide rail (29) is fixed to the opening of the four-column loading frame (25) through the triangular support frame (31), the tray (34) is slidably arranged on the linear guide rail (29), the tray (34) is provided with the counterforce pull rod on one side, the counterforce pull rod passes through the side wall of the four-column loading frame (25) opposite to the opening and is connected to the fastening cap (32), the fastening cap (32) abuts against the outer side wall of the four-column loading frame (25), the top surface of the tray (34) is provided with a groove along the working direction of the x-direction servo cylinder (19), the x-direction friction reduction roller row (36) is rollingly arranged at the bottom of the groove, the shear box (17) can be arranged in the groove and supported on the x-direction friction reduction roller row (36), the friction reduction ball strip (35) is rollingly arranged on the side wall of the groove and can rollingly contact the shear box (17), and the side wall of the tray (34) is provided with a stop block (37) which can abut against the x-direction friction reduction roller row (36).

3. The large-scale triaxial dynamic soil integration shearing test system according to claim 2, characterized in that: The single shear shear box (8) comprises a base (21), a stacked ring upper shear box (38), a guide column (39), a y-direction friction-reducing roller row (40), a shear pressure head (41), an acoustic emission stacked ring (43), a general stacked ring (44), an x-direction counterforce backing plate (45), an x-direction counterforce backup cap (46), a stacked ring lower shear box (47), a y-direction counterforce backup cap (48), a connecting backup cap (49), a y-direction counterforce backing plate (50), the stacked ring lower shear box (47) is arranged on the base (21), the general stacked ring (44) is arranged on the top of the stacked ring lower shear box (47), the acoustic emission stacked ring (43) is arranged on the top of the general stacked ring (44), the stacked ring upper shear box (38) is arranged on the top of the acoustic emission stacked ring (43), the shear pressure head (41) is arranged on the top of the stacked ring upper shear box (38), the y-direction friction-reducing roller row (40) is arranged on the top of the shear pressure head (41) and rolls, the z-direction pressure head (16) is supported on the y-direction friction-reducing roller row (40), the loading end of the z-direction servo cylinder (11) is abutted to the z-direction pressure head (16), the guide column (39) is detachably arranged on the stacked ring upper shear box (38) and is downwardly connected to the stacked ring lower shear box (47), the acoustic emission stacked ring (43) and the general stacked ring (44) are sleeved on the guide column (39), the x-direction counterforce backing plate (45) is arranged on the side wall of the stacked ring lower shear box (47), the x-direction counterforce backup cap (46) is arranged on the x-direction counterforce backing plate (45), the loading end of the x-direction servo cylinder (19) is abutted to the x-direction counterforce backup cap (46), the y-direction counterforce backing plate (50) is arranged on the side wall of the stacked ring upper shear box (38), the y-direction counterforce backup cap (48) is arranged on the y-direction counterforce backing plate (50) through the connecting backup cap (49), and the loading end of the y-direction servo cylinder (23) is abutted to the y-direction counterforce backup cap (48).

4. The large-scale triaxial dynamic soil integration shearing test system according to claim 3, characterized in that: The base (21) can be arranged in a groove and supported on the x-direction friction-reducing roller row (36), and the friction-reducing ball strip (35) can be in rolling contact with the side wall of the base (21).

5. The large-scale triaxial dynamic soil integration shearing test system according to claim 3, characterized in that: The data acquisition system comprises a z-direction magnetostrictive displacement sensor (10), an x-direction magnetostrictive displacement sensor (20), a y-direction magnetostrictive displacement sensor (22), a z-direction shear plate type load sensor (14), an x-direction Folen sensor (18) and a y-direction Folen sensor (24), the z-direction magnetostrictive displacement sensor (10), the x-direction magnetostrictive displacement sensor (20) and the y-direction magnetostrictive displacement sensor (22) are respectively arranged on the end face of the cylinder barrel of the z-direction servo cylinder (11), the end face of the cylinder barrel of the x-direction servo cylinder (19) and the end face of the cylinder barrel of the y-direction servo cylinder (23), one end of the z-direction shear plate type load sensor (14) is connected to the loading end of the z-direction servo cylinder (11) through a load sensor backup cap (13), the other end of the z-direction shear plate type load sensor (14) is abutted to the z-direction pressure head (16) through a ball head compression plate (15), the x-direction Folen sensor (18) is arranged on the loading end of the x-direction servo cylinder (19) and abutted to the x-direction counterforce backup cap (46), and the y-direction Folen sensor (24) is arranged on the loading end of the y-direction servo cylinder (23) and abutted to the y-direction counterforce backup cap (48).

6. The large-scale triaxial dynamic soil integration shearing test system according to claim 5, characterized in that: The four-column loading frame (25) is provided with a connecting seat (26) at the top, the cylinder barrel of the z-direction servo cylinder (11) is connected to the connecting seat (26) through a high flange (12), the side wall of the four-column loading frame (25) is provided with an x-direction Follen sensor connecting hole (30) and a y-direction Follen sensor connecting hole (33), the cylinder barrel of the x-direction servo cylinder (19) is arranged at the x-direction Follen sensor connecting hole (30) through a connecting flange, the loading end of the x-direction servo cylinder (19) penetrates through the x-direction Follen sensor connecting hole (30) and is connected to the x-direction Follen sensor (18), the cylinder barrel of the y-direction servo cylinder (23) is arranged at the y-direction Follen sensor connecting hole (33) through a connecting flange, the loading end of the y-direction servo cylinder (23) penetrates through the y-direction Follen sensor connecting hole (33) and is connected to the y-direction Follen sensor (24), and the four-column loading frame (25) is further provided with a lifting ring (27) at the top.

7. The test method of the large-scale triaxial dynamic soil integration shear test system according to claim 2, characterized in that, The method comprises the following steps: S1, starting and checking whether each device and instrument is normal; S2, selecting a shear box (17) of a corresponding type and size according to the type and size of the sample, placing the shear box (17) on the x-direction antifriction roller (36) in the sample transportation system, and then putting the sample into the shear box (17); S3, transporting the shear box (17) to the position directly below the z-direction pressure head (16) through the sample transportation system, penetrating the counterforce pull rod through the side wall of the four-column loading frame (25), and then tightening the fastening cap (32); S4, applying a preset normal pressure to the shear box (17) through the z-direction servo cylinder (11), then applying an initial tangential pressure to the shear box (17) through the x-direction servo cylinder (19) and the y-direction servo cylinder (23) respectively, and finally performing different types of shear tests on the sample under the conditions of constant normal load, dynamic normal load or constant normal stiffness through the z-direction servo cylinder (11), the x-direction servo cylinder (19) and the y-direction servo cylinder (23) until the sample reaches a preset shear displacement or deformation, and collecting the loading parameters of the z-direction servo cylinder (11), the x-direction servo cylinder (19) and the y-direction servo cylinder (23) by the data acquisition system during the test process; S5, when the sample reaches the preset shear displacement or deformation, automatically stopping and saving the test data, and processing and analyzing the data collected by the data acquisition system by the computer control system (2).

8. The test method of the large-scale triaxial dynamic geotechnical integrated shear test system according to claim 7, characterized in that: The shear test includes three types of three-directional single shear test, three-directional direct shear test and three-directional cyclic shear test.

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