An experimental device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutters.

Abstract

This invention relates to the field of tunnel boring machine (TBM) cutter testing technology, and discloses a test device for simulating the damage behavior of TBM cutterheads under impact and cutting action. The device includes a housing, an impact loading assembly, a cutter mounting platform, a horizontal movement assembly, a sample clamping assembly, and a data acquisition assembly. The impact loading assembly is located at the top of the housing, the cutter mounting platform is located at the bottom of the impact loading assembly, and a first cutter holder is provided on the side wall of the cutter mounting platform. The horizontal movement assembly is located inside the housing, and the sample clamping assembly is located on the surface of the horizontal movement assembly. By laterally mounting the cutterheads, continuous impact and cutting actions are achieved. Combined with an adjustable sample position structure to avoid interference, and multi-dimensional data acquisition, the device can accurately simulate the actual working conditions of the cutterheads under complex geological conditions, comprehensively capturing their stress response and damage evolution characteristics. This provides key support for optimizing cutter design, improving tunneling reliability, and reducing construction risks, effectively overcoming the limitations of existing single loading or static tests.

Description

Technical Field

[0001] This invention relates to the field of tunnel boring machine cutter testing technology, specifically to a test device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutters. Background Technology

[0002] As the core cutting component of the tunnel boring machine's rock-breaking system, the cutterhead's working condition directly affects tunneling efficiency, equipment stability, and construction costs. During tunnel construction, the cutterhead must operate continuously in complex geological environments, bearing not only the rolling cutting load from the cutterhead's rotation but also irregular impact loads induced by factors such as geological heterogeneity, joints, fissures, and hard interlayers. This results in the cutterhead being under a long-term combined "impact-cutting" condition. Under such complex load conditions, the cutterhead is prone to failure modes such as material spalling and fatigue cracks, which can lead to frequent cutter replacements and damage to the cutterhead structure, among other construction risks. Therefore, accurately assessing the stress response and damage evolution characteristics of the cutterhead under combined impact-cutting loads is crucial for improving the reliability of cutterhead design and optimizing tunneling parameters.

[0003] However, existing cutter testing devices are mostly based on a single loading mode, or can only conduct static wear tests or impact toughness tests, and cannot effectively reproduce the actual stress state of the cutter under the coupling of rolling and impact during shield tunneling.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a test device for simulating the damage behavior of shield tunnel cutter under impact and cutting action, aiming to solve the problem that existing cutter test devices are mostly based on a single loading mode and cannot effectively reproduce the actual stress state of the cutter under the coupled action of rolling and impact during shield construction.

[0006] The technical solution adopted by this invention to solve the technical problem is as follows:

[0007] An experimental device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutters includes:

[0008] case;

[0009] An impact loading assembly, disposed at the top of the housing and extending into the interior of the housing, is used to apply controllable impact and cutting load to the hob;

[0010] A tool mounting platform is located inside the housing and disposed at the bottom of the impact loading assembly; a first tool holder is provided on the side wall of the tool mounting platform for mounting a hobbing cutter;

[0011] A sample clamping assembly, located inside the housing, is used to clamp the sample;

[0012] A horizontal moving component is disposed inside the housing and located below the impact loading component; the horizontal moving component is connected to the sample clamping component to drive the sample clamping component to move horizontally;

[0013] The acquisition component, located inside the housing, is used to acquire test videos and images of the hob.

[0014] Furthermore, the impact loading component includes:

[0015] A servo electric cylinder is disposed at the top of the housing; the output shaft of the servo electric cylinder is located inside the housing; the tool mounting table is disposed at the bottom of the output shaft of the servo electric cylinder;

[0016] A guide assembly is disposed on the housing; the guide assembly is connected to the tool mounting table.

[0017] Furthermore, the guiding component includes:

[0018] Multiple guide bearings are disposed on the housing;

[0019] Multiple guide rods are slidably disposed within multiple guide bearings; one end of each guide rod is connected to the tool mounting table.

[0020] Furthermore, an angle adjustment component is provided at the bottom of the first tool holder for adjusting the angle of the first tool holder.

[0021] Furthermore, a triaxial acceleration sensor and a triaxial force sensor are provided between the angle adjustment component and the tool mounting table.

[0022] Furthermore, the sample clamping assembly includes:

[0023] A fixed platform is disposed on the surface of the horizontally moving component;

[0024] Four adjustable clamps are disposed on the surface of the fixed platform and located around the fixed platform to enclose a clamping space.

[0025] Furthermore, the fixed platform is provided with multiple sets of fixed slots, each set of fixed slots including two T-slots. The bottom of the adjustable clamp is provided with a through hole corresponding to the T-slot. A T-bolt is provided in the T-slot. The T-bolt passes through the through hole and cooperates with a nut to connect the adjustable clamp to the fixed platform.

[0026] Furthermore, the horizontal movement component includes:

[0027] The first lead screw module is arranged laterally inside the housing;

[0028] The second lead screw module is longitudinally mounted on the slider of the first lead screw module; the fixed platform is mounted on the slider of the second lead screw module.

[0029] Furthermore, it also includes:

[0030] The second tool holder is located on the bottom wall of the tool mounting platform and is used to mount the hobbing cutter.

[0031] Furthermore, the acquisition component includes:

[0032] A high-speed camera is installed on the inner wall of the housing to capture the impact and cutting process of the hob, and to collect the impact response, fracture process and motion behavior.

[0033] The ultra-depth-of-field microscope is detachably installed inside the housing and is used to acquire images of the wear area of ​​the hob and the microscopic wear morphology of the hob.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] In this invention, the impact and cutting actions are achieved by side-mounting the roller cutter. Combined with the adjustable structure of the sample position to avoid interference, and with multi-dimensional data acquisition, the actual working conditions of the roller cutter under complex geological conditions can be accurately simulated, and its stress response and damage evolution characteristics can be fully captured. This provides key support for optimizing the cutter design, improving tunneling reliability and reducing construction risks, and effectively makes up for the limitations of existing single loading or static tests. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0037] Figure 2 This is a schematic diagram of the impact loading component structure of the present invention.

[0038] Figure 3 This is a schematic diagram of the first and second tool holders of the present invention.

[0039] Figure 4 This is a schematic diagram of the adjustable clamp structure of the present invention.

[0040] The numbers in the diagram represent: 1. Housing; 2. Impact loading assembly; 21. Servo electric cylinder; 22. Guide assembly; 221. Guide bearing; 222. Guide rod; 3. Tool mounting table; 31. First tool holder; 32. Second tool holder; 4. Horizontal movement assembly; 41. First lead screw module; 42. Second lead screw module; 5. Sample clamping assembly; 51. Fixed table; 52. Adjustable clamp; 521. L-shaped block; 522. Top holding lead screw; 523. Top plate; 53. T-slot; 54. Through hole; 6. Sample; 7. Hob. Detailed Implementation

[0041] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0042] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0043] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0044] In existing technologies, the cutterhead 7, as a core component of the tunnel boring machine's rock-breaking system, directly impacts construction efficiency and cost. Existing testing devices mostly employ single-loading modes, such as static wear tests or independent impact tests, which cannot simulate the combined impact and cutting loads experienced by the cutterhead 7 under actual working conditions. This limitation results in test data that cannot accurately reflect the actual damage behavior of the cutterhead under complex geological conditions, making it difficult to guide cutterhead optimization design and construction parameter adjustments. For example, when the cutterhead 7 operates in strata containing hard interlayers, existing devices cannot simultaneously apply rolling cutting and instantaneous impact loads, leading to deviations in the study of the cutterhead's fatigue crack propagation mechanism.

[0045] In view of the shortcomings of the prior art, this embodiment provides an experimental device for simulating the damage behavior under the impact and cutting action of the tunnel boring machine cutterhead, as detailed below:

[0046] As attached Figure 1 and attached Figure 3 As shown, an experimental device for simulating the damage behavior of a tunnel boring machine cutter under impact and cutting action includes a housing 1, an impact loading assembly 2, a cutter mounting platform 3, a horizontal movement assembly 4, a sample clamping assembly 5, and a data acquisition assembly. The impact loading assembly 2 is located at the top of the housing 1 and extends into the interior of the housing 1. The impact loading assembly 2 is used to apply controllable impact and cutting loads to the cutter 7. The cutter mounting platform 3 is located at the bottom of the impact loading assembly 2, and a first cutter holder 31 is provided on the side wall of the cutter mounting platform 3 for mounting the cutter 7. The sample clamping assembly 5 is located inside the housing 1 and is used to clamp the sample 6. The horizontal movement assembly 4 is located inside the housing 1 and below the impact loading assembly 2, and is connected to the sample clamping assembly 5. It is used to adjust the horizontal position of the sample 6 to facilitate impact and cutting tests. The data acquisition assembly is also provided inside the housing 1. The data acquisition assembly can be used to acquire crack propagation images, dynamic videos of the fracture process, and microscopic images of the wear area of ​​the cutter 7, etc.

[0047] The shell 1 refers to the rigid frame structure that supports the various functional modules, which can be made of welded steel plates or cast boxes, providing a stable foundation for the transmission of impact loads. The impact loading assembly 2 refers to the drive mechanism that generates controllable dynamic loads, which can be implemented by a servo electric cylinder 21 in conjunction with a guiding mechanism, controlling the impact energy and frequency by adjusting the output shaft stroke and speed. The tool mounting table 3 refers to the transition structure connecting the impact loading assembly 2 and the hob 7. The first tool holder 31 set on its side wall can be designed as a mounting plate with bolt fixing holes, so that the axis of the hob 7 is parallel to the horizontal plane by lateral installation, avoiding contact between the tool holder and the sample 6 during vertical impact. The horizontal movement assembly 4 refers to the transmission mechanism that realizes the two-dimensional positioning of the sample 6, which can be made by a combination of a lead screw module and a servo motor, simulating different cutting trajectories by controlling the displacement in two orthogonal directions. The sample clamping assembly 5 refers to the device for fixing the rock sample 6, which can be designed as a fixed table 51 with an adjustable clamp 52, which can adapt to different sizes of samples 6 by adjusting the position of the adjustable clamp 52. The data acquisition component refers to the sensor system that records data during the test process. Specifically, it may include a high-speed camera and a force sensor to capture the motion trajectory and force state of the hob 7.

[0048] Specifically, the servo electric cylinder 21 drives the tool mounting platform 3 to move vertically, causing the laterally mounted hob 7 to impact the sample 6. Under the continuous action of the impact loading component 2, the hob 7 moves downward and cuts the sample 6. During this process, the lateral mounting ensures that the hob 7 directly enters the cutting position at the end of its impact stroke, avoiding the obstruction of the sample 6 by the tool holder in the traditional bottom mounting method. The two-dimensional motion platform achieves precise adjustment of the sample 6 at any position in the horizontal plane through the orthogonal lead screw module. Combined with the stroke control of the impact loading component 2, it can simulate combined working conditions with different impact depths and cutting speeds. A high-speed camera records the crack propagation process on the surface of the hob 7 in real time, and a force sensor simultaneously acquires triaxial load data, providing a complete data chain for analyzing the damage mechanism under combined loads.

[0049] Compared to existing technologies, traditional devices require repositioning after impact due to the vertical mounting of the tool before cutting tests can be conducted. This solution, however, achieves seamless integration of impact and cutting actions through lateral mounting. Existing technologies, with the specimen 6 fixed in position, only allow for single-point impact testing. This solution uses the horizontal moving component 4 to simulate continuous cutting paths. Existing test data acquisition is largely limited to static wear measurement; this solution integrates dynamic imaging and multi-directional force sensing to achieve full-process monitoring of tool damage behavior.

[0050] Through the above technical solutions, this application realizes the realistic working condition simulation of the shield tunnel cutter 7 under combined impact and cutting loads, solving the technical problem that traditional test devices cannot simultaneously apply dynamic impact and continuous cutting loads. The lateral mounting structure effectively eliminates spatial interference between the cutter holder and the specimen 6, ensuring the continuous execution of the combined loading action. The coordinated work of the two-dimensional motion platform and the data acquisition system provides a reliable test platform for studying the damage evolution law of the cutter 7.

[0051] In this embodiment, sample 6 can be a rock of different shapes and materials or a rock substitute of other materials.

[0052] As attached Figure 2 As shown, in this embodiment, the impact loading assembly 2 includes a servo electric cylinder 21 and a guide assembly 22. The servo electric cylinder 21 is disposed on the top of the housing 1, and its output shaft is located inside the housing 1. The tool mounting table 3 is disposed at the bottom of the output shaft of the servo electric cylinder 21. The guide assembly 22 is disposed on the housing 1 and connected to the tool mounting table 3.

[0053] Among them, the servo electric cylinder 21 refers to a linear actuator driven by a servo motor, which can be implemented using an electric cylinder with position feedback function. Its output shaft stroke and speed can be precisely adjusted by the electronic control system to control the application of impact loads. The guide assembly 22 refers to the mechanism that restricts the movement trajectory of the tool mounting table 3, which can be implemented by a structure in which a guide rod 222 cooperates with a guide bearing 221. The guide rod 222 is slidably disposed in the guide bearing 221 and rigidly connected to the tool mounting table 3 to constrain the vertical degree of freedom of the tool mounting table 3.

[0054] Specifically, the output shaft of the servo cylinder 21 directly drives the tool mounting table 3 to move vertically. By adjusting the stroke and speed parameters of the cylinder, impact loads of different amplitudes and frequencies can be simulated. After the guide rod 222 of the guide assembly 22 is connected to the tool mounting table 3, when the servo cylinder 21 applies the impact load, the guide rod 222 slides along the inner wall of the guide bearing 221, limiting the lateral displacement of the tool mounting table 3. Thus, the tool mounting table 3 moves only in the vertical direction during the impact, avoiding abnormal contact between the hob 7 and the sample 6 due to lateral offset. The closed-loop control characteristics of the servo cylinder 21 can adjust the output force in real time to ensure the continuous application of impact load and cutting load.

[0055] Through the above technical solutions, this application achieves precise loading control of the hob 7 under combined impact and cutting loads, ensuring the stability of the motion trajectory of the tool mounting platform 3. The closed-loop control characteristics of the servo electric cylinder 21 can accurately reproduce the dynamic impact load in actual working conditions, and the guide assembly 22 avoids unintended contact between the tool and the sample 6 through mechanical limiting, ensuring the repeatability of the test process and the reliability of the data.

[0056] As attached Figure 2 As shown, in this embodiment, the guide assembly 22 includes multiple guide bearings 221 and multiple guide rods 222. The guide bearings 221 are disposed on the housing 1, and the guide rods 222 are slidably disposed in the guide bearings 221 and connected to the tool mounting table 3.

[0057] Specifically, multiple guide bearings 221 are evenly arranged on the housing 1, and the guide bearings 221 are parallel. When the guide rods 222 slide in the inner bore of the bearings, the radial clearance is eliminated through the precision-machined mating surfaces. When an impact load is applied to the tool mounting table 3, the guide rods 222 transmit the vertical impact force along the bearing axis. At the same time, the symmetrical arrangement of the multiple guide rods 222 decomposes the lateral torque generated by the cutting load into shear stresses of each rod. The lubricating medium inside the guide bearings 221 can be a solid lubricating film or an oil film, controlling the sliding friction coefficient within a predetermined range. By adjusting the distribution angle and number of the guide rods 222, different constraint combinations in different directions are formed, ensuring the degree of freedom in the impact direction while suppressing tool deflection.

[0058] Through the above technical solutions, this application can eliminate the non-axial displacement of the tool under combined loads, ensure precise synchronization between impact and cutting actions, and solve the problem of test data distortion caused by motion trajectory deviation. The low-friction fit between the guide bearing 221 and the guide rod 222 significantly reduces motion resistance, allowing the tool mounting platform 3 to maintain a stable motion state during impact, providing a basic condition for the sensor to collect real load data. The multi-axis guiding structure effectively suppresses tool deflection through mechanical decomposition, making the contact state between the hob 7 and the sample 6 closer to the actual working condition, and improving the reliability of the test results.

[0059] In this embodiment, an angle adjustment member is provided at the bottom of the first tool holder 31 to adjust the angle of the first tool holder 31.

[0060] The angle adjustment component refers to a mechanical connection part that can change the relative angle between the tool holder and the tool mounting platform 3 (i.e., the first tool holder 31 rotates on one side of the tool mounting platform 3, so that the side wall of the first tool holder 31 forms a certain angle with the side wall of the tool mounting platform 3). Specifically, it can be implemented using a universal hinge structure or a worm gear mechanism, and the angle is fixed by locking. This component acts directly on the bottom of the tool holder, and by adjusting its rotation angle, it changes the contact direction between the hob 7 and the sample 6, thereby adapting to the requirements of different geological conditions for the tool entry angle.

[0061] Specifically, the angle adjustment component connects the first tool holder 31 to the tool mounting platform 3 via a mechanical connection structure. When the angle of the hob 7 needs to be adjusted, the rotation range of the angle adjustment component can be controlled manually or through a drive device. For example, when simulating the hob 7 encountering an inclined rock layer, the tool holder is rotated to a specific angle through a worm gear mechanism, causing the hob 7 to cut into the sample 6 in an inclined direction. During the adjustment process, the bottom mounting position of the angle adjustment component avoids spatial interference with the sample clamping assembly 5, ensuring the continuous transmission of the vertical load and cutting load applied by the impact loading assembly 2. The flexible adjustment of the hob 7 angle allows the test device to reproduce the multi-angle stress state of the tool under actual working conditions caused by factors such as rock joints and hard interlayers, thereby accurately collecting stress distribution and damage data of the tool at different angles.

[0062] Compared with existing technologies, traditional testing devices have a fixed cutter installation angle, which cannot simulate the actual cutting direction of the hob 7 under complex geological conditions. This solution, however, achieves dynamic adjustment of the hob 7 installation angle through an angle adjustment component. This allows the hob 7 to change its cutting angle during the test based on preset parameters or real-time feedback, solving the problem that existing devices cannot adapt to multi-angle impact cutting conditions.

[0063] Through the above technical solution, this application can accurately control the contact angle between the hob 7 and the sample 6, so that the test device can truly reflect the stress state and damage evolution law of the hob 7 when simulating complex working conditions such as different rock strata dip angles and joint distributions, and provide effective data support for analyzing the failure mechanism of the tool under impact-cutting combined load.

[0064] In this embodiment, the angle adjustment component can be a fixed disc, a drive motor, or a rotary cylinder. The fixed disc is fixedly connected to the tool mounting table 3 and has multiple threaded holes arranged in a ring. The first tool holder 31 has through holes 54 corresponding to the threaded holes. Bolts can be installed in the through holes 54, and the fixed disc can be connected to the angle adjustment component by the engagement of the bolts with the threaded holes. Simultaneously, the angle of the first tool holder 31 can be adjusted by adjusting the relative position of each through hole 54 and the threaded hole. The drive motor can drive the first tool holder 31 to rotate a certain angle via gears or direct connection. One end of the rotary cylinder is connected to the tool mounting table 3, and the other rotating end is connected to the first tool holder 31, thereby adjusting the rotation angle through pneumatic control components.

[0065] In this embodiment, a triaxial acceleration sensor and a triaxial force sensor are provided between the angle adjustment component and the tool mounting table 3.

[0066] The triaxial accelerometer is a sensor capable of simultaneously detecting accelerations in three orthogonal directions (X, Y, and Z). It can be implemented using piezoelectric or MEMS (Micro-Electro-Mechanical System) sensors to capture the spatial vibration characteristics of the hob 7 under combined impact and cutting loads. The triaxial force sensor is a sensor capable of simultaneously measuring forces acting in three orthogonal directions. It can be implemented using strain gauge or piezoelectric crystal sensors to quantify the multiaxial force components generated by the hob 7 during impact and cutting.

[0067] Specifically, a triaxial accelerometer is integrated at the connection between the angle adjustment component and the tool mounting platform 3. By measuring acceleration data along three axes, it reflects the real-time motion changes of the hob 7 under dynamic impact loads. A triaxial force sensor and an accelerometer are arranged side-by-side to directly acquire spatial force distribution data of the tool under the combined effects of cutting and impact. The measurement signals from both are processed by a synchronous acquisition system to form a time-correlated multidimensional dataset, thus comprehensively characterizing the dynamic response characteristics of the hob 7 under angle adjustment.

[0068] Through the above technical solution, this application realizes three-dimensional dynamic response monitoring of hob 7 during the angle adjustment process, which can accurately quantify the spatial distribution characteristics of the combined impact and cutting loads, provide high-precision multi-dimensional experimental data for analyzing the damage evolution mechanism of hob 7, and at the same time ensure the consistency between the sensor measurement data and the actual stress state of the tool.

[0069] As attached Figure 2 and attached Figure 4 As shown, in this embodiment, the sample clamping assembly 5 includes a fixed platform 51 and four adjustable clamps 52. The fixed platform 51 is disposed on the surface of the horizontal moving assembly 4, and the four adjustable clamps 52 are disposed on the surface of the fixed platform 51. The four adjustable clamps 52 enclose a clamping space, which is used to place the sample 6.

[0070] The fixed platform 51 is a rigid support platform that supports the sample 6. It can be made of metal and machined into a rectangular plate structure, connected to the slider of the horizontal moving assembly 4 by bolts. Its function is to provide a stable mounting base for the clamps, ensuring that the sample 6 does not undergo overall displacement under impact load. The adjustable clamp 52 is a clamping unit with adjustable position. It can be a jaw structure with threaded rods. The jaws are moved along the guide rail by rotating the handle. Its function is to independently adjust the position of each clamp to form a clamping space that matches the shape of the sample 6, eliminating the gap between the sample 6 and the clamps.

[0071] Specifically, the fixed stage 51, acting as a rigid reference surface, is rigidly connected to the horizontal moving assembly 4. When the specimen 6 is impacted, its own stiffness suppresses vibration transmission. Four adjustable grippers 52 are located on the four sides of the fixed stage 51. By adjusting the position of each gripper, a rectangular closed area is formed inside the grippers. When the specimen 6 is placed in the gripping space, each gripper moves synchronously towards the center until the grippers contact the surface of the specimen 6. At this point, the four-sided clamping force forms a spatial constraint, preventing the specimen 6 from sliding or rotating under cutting loads. For example, when the specimen 6 is an irregular polygon, the position of the corresponding side gripper can be adjusted individually to keep the grippers in parallel contact with the edge of the specimen 6, ensuring a uniform distribution of clamping force.

[0072] Through the above technical solution, this application achieves all-round constraint of the specimen 6 under composite load, effectively suppressing the displacement of the specimen 6 caused by impact vibration. At the same time, through the independent adjustment function of the adjustable clamp 52, it can be compatible with specimens 6 of different sizes and shapes, such as rectangular rock specimens 6 with side lengths ranging from 100 mm to 500 mm or cylindrical concrete specimens 6 with diameters ranging from 200 mm to 400 mm, solving the problem of test data deviation caused by insufficient clamping adaptability of traditional devices.

[0073] As attached Figure 4 As shown, in this embodiment, the fixed platform 51 is provided with multiple sets of fixed slots, each set of fixed slots including two T-shaped slots 53. The bottom of the adjustable clamp 52 is provided with a through hole 54 corresponding to the T-shaped slot 53. A T-shaped bolt is provided in the T-shaped slot 53. The T-shaped bolt passes through the through hole 54 and cooperates with the nut to connect the adjustable clamp 52 to the fixed platform 51.

[0074] The T-slot 53 refers to a continuous groove with a T-shaped cross-section opened along the surface of the fixed platform 51. It can be achieved through milling or casting. Its width matches the head size of the T-bolt and is used to limit the lateral displacement of the bolt within the groove. The through hole 54 refers to a circular hole penetrating the bottom of the adjustable clamp 52. It can be achieved through drilling. The hole diameter is slightly larger than the diameter of the T-bolt shank, allowing the bolt to pass freely but restricting radial movement. The T-bolt is a fastener with a T-shaped head. It can be forged or machined. Its head is embedded in the T-slot 53 and slides along the groove. The shank passes through the through hole 54 and engages with the nut to form an axial constraint. The nut is a fastener that threads with the T-bolt. It can be a hexagonal nut or a flange nut. Tightening it generates a preload, pressing the adjustable clamp 52 against the surface of the fixed platform 51.

[0075] Specifically, multiple sets of fixing slots are arranged in a matrix along the surface of the fixing platform 51, each set containing two parallel T-slots 53, forming selectable installation positions. When the position of the clamp needs to be adjusted, the head of the T-bolt is inserted into the T-slot 53 at the selected position, and after sliding along the slot to the target position, the through hole 54 at the bottom of the clamp is fitted into the bolt shank, and then the nut is tightened to form a rigid connection between the clamp and the fixing platform 51. During this process, the continuous structure of the T-slots 53 allows the clamp to stay in any position, while the locking action of the nut eliminates the gap between the clamp and the fixing platform 51, preventing displacement during the test.

[0076] Through the above technical solution, this application realizes the rapid positioning and rigid fixation of the clamp at any position on the surface of the fixed stage 51, which solves the problem that traditional devices cannot take into account both adjustment flexibility and clamping stability. It can adapt to the clamping requirements of samples 6 of different sizes, while simplifying the operation process and reducing manufacturing costs.

[0077] As attached Figure 4 As shown, in this embodiment, the adjustable clamp 52 includes an L-shaped block 521, a top holding screw 522, and a top plate 523. The bottom of the L-shaped block 521 is provided with a through hole 54 for connection with a T-bolt. The side of the L-shaped block 521 facing the sample 6 is provided with an adjustment threaded hole. The top holding screw 522 is threaded into the adjustment threaded hole. The side of the top holding screw 522 close to the sample 6 is provided with a top plate 523. The top plate 523 abuts against the sample 6. The four top plates 523 cooperate with each other to fix the sample 6.

[0078] The adjustable clamp 52 achieves stable installation through the cooperation of L-shaped block 521 and T-bolt. The top plate 523 flexibly holds the sample 6 by using the threaded engagement of the top screw 522 and the adjusting threaded hole. The four top plates 523 work together to fix the sample 6 from multiple directions. It can not only adapt to the clamping requirements of samples 6 of different sizes, but also precisely control the clamping force through the screw adjustment, ensuring that the sample 6 is stable and does not deviate during the test, thus improving the flexibility and reliability of clamping.

[0079] As attached Figure 2 As shown, in this embodiment, the horizontal moving component 4 includes a first lead screw module 41 that is laterally disposed inside the housing 1, a second lead screw module 42 that is longitudinally disposed on the slider of the first lead screw module 41, and a fixed platform 51 disposed on the slider of the second lead screw module 42.

[0080] The first lead screw module 41 refers to a mechanical transmission device that achieves linear motion through the cooperation of a lead screw and a nut. Specifically, it can be implemented using a ball screw and a servo motor drive. Its lateral arrangement allows for a wide range of horizontal position adjustment of the sample 6. The second lead screw module 42 refers to a transmission device that forms an orthogonal layout with the first lead screw module 41. Specifically, it can use a ball screw of the same structure mounted on the moving slider of the first lead screw module 41. Its longitudinal arrangement allows for displacement adjustment of the sample 6 in a direction perpendicular to the lateral direction. The rigid connection between the fixed stage 51 and the slider of the second lead screw module 42 eliminates the influence of transmission backlash on positioning accuracy. This can be achieved by bolt fastening or welding, ensuring the stability of the sample clamping assembly 5 during compound motion.

[0081] Specifically, when the first lead screw module 41 moves laterally, it drives the second lead screw module 42 to translate as a whole. When the second lead screw module 42 moves longitudinally, it drives the fixed platform 51 to move individually. The superposition of the two movements forms a motion trajectory in any direction within the plane. When it is necessary to simulate the combined impact and cutting action of the hob 7, the sample 6 can be moved along a preset path in the horizontal plane by controlling the timing and displacement of the two lead screw modules. For example, during the simulation of continuous cutting by the hob 7, the second lead screw module 42 can maintain its longitudinal position, while the first lead screw module 41 drives the sample 6 to move laterally at a uniform speed. When it is necessary to simulate positional displacement under impact load, the second lead screw module 42 can quickly adjust its longitudinal displacement. The two lead screw modules form a two-dimensional motion platform through a series structure. Their orthogonal layout avoids motion interference, while the high transmission accuracy of the ball screw achieves micron-level positioning of the sample 6.

[0082] Through the above technical solution, this application achieves precise position adjustment of sample 6 in two degrees of freedom in the horizontal plane, enabling simulation of the combined stress state of shield tunnel cutter 7 under different impact angles and cutting paths. By programmatically controlling the motion parameters of the two lead screw modules, the complex motion trajectory of cutter 7 in actual working conditions can be reproduced, providing accurate experimental conditions for studying tool damage behavior under the coupled action of impact and cutting. The rigid connection structure effectively avoids positioning errors caused by transmission backlash, ensuring the consistency of sample 6's position with the preset trajectory during the test.

[0083] As attached Figure 3 As shown, in this embodiment, a second tool holder 32 is provided on the bottom wall of the tool mounting platform 3 for mounting the hob 7 to achieve single-point impact and cutting processes, and cooperates with the first tool holder 31 to achieve different functions.

[0084] Specifically, when the hob 7 is mounted on the second tool holder 32, the impact loading component 2 drives the tool mounting platform 3 to move vertically downwards, causing the hob 7 to apply a single-point impact or continuous cutting load to the surface of the sample 6. Since the hob 7 is mounted in the same direction as the movement, the impact speed and cutting depth, as well as tests at different positions, can be precisely controlled. When simulating cutting loading, the hob 7 on the second tool holder 32 can be placed in contact with or offset from the sample 6, and then the first lead screw module 41 and / or the second lead screw module 42 can be activated to realize the cutting process of the hob 7 on the second tool holder 32. The two tool holders achieve rapid switching of loading modes through complementary positions, enabling independent single-load tests as well as combinations to form multi-dimensional loading conditions, comprehensively covering the stress scenarios of the hob 7 under actual working conditions.

[0085] In some specific embodiments, a quick-release interface can be provided between the second tool holder 32 and the tool mounting table 3, for example, using a dovetail groove with a locating pin structure, to facilitate quick replacement of different tool holders. The mounting surface of the bottom wall tool holder can be machined into a planar structure to accommodate the different mounting angles of the hobs 7.

[0086] Through the above technical solutions, this application can realize independent or combined testing of single-point impact cutting and lateral composite loading of the hob 7, effectively avoiding motion interference between the tool holder and the specimen 6, and improving the accuracy of test data. Through the coordinated design of the tool holder position and function, the device possesses multi-dimensional load simulation capabilities, providing comprehensive test conditions for studying the damage behavior of the hob 7 under different working conditions.

[0087] In this embodiment, an angle adjustment component, a triaxial acceleration sensor, and a triaxial force sensor may be provided between the second tool holder 32 and the tool mounting platform 3.

[0088] In this embodiment, the acquisition components include a high-speed camera and a super depth-of-field microscope. The high-speed camera is mounted on the inner wall of the housing 1 and is used to capture the impact and cutting process of the hob 7, and to acquire impact response, fracture process, and motion video. The super depth-of-field microscope is detachably mounted inside the housing 1 and is used to acquire images of the wear area of ​​the hob 7, as well as the microscopic wear morphology of the hob 7.

[0089] Specifically, during the impact-cutting combined load test, a high-speed camera was triggered to continuously capture images, recording the interaction process between the hob 7 and the specimen 6 through time-series images. The instantaneous motion trajectory of the hob 7 under the impact load and the fracture mode of the specimen 6 were completely captured and converted into dynamic response data. After the test, the hob 7 was disassembled and placed on the observation platform of a super depth-of-field microscope, or the super depth-of-field microscope was directly set inside the housing 1, and the three-dimensional morphological data of the tool contact surface were obtained through multi-angle illumination and depth-of-field synthesis technology. The data from both devices were correlated with timestamps and spatial coordinates to form a correspondence between the macroscopic dynamic process and the microscopic morphological features.

[0090] Through the above technical solution, this application solves the technical problem that existing experimental devices cannot simultaneously acquire the dynamic damage process and static microstructure of the hob 7. Dynamic image data from a high-speed camera reveals the crack initiation and propagation mechanism under impact-cutting coupling, while microscopic morphology data from a super-depth-of-field microscope quantifies the wear depth and material failure mode. The synergistic application of both provides multi-dimensional data support for the quantitative analysis of the damage behavior of the hob 7.

[0091] In this embodiment, there are multiple high-speed cameras, which can be respectively installed on the side wall and top wall inside the housing 1 to facilitate all-round observation of the impact and cutting process of the hob 7.

[0092] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the solutions disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the claims.

Claims

1. A test device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutterheads, characterized in that, include: case; An impact loading assembly, disposed at the top of the housing and extending into the interior of the housing, is used to apply controllable impact and cutting load to the hob; A tool mounting platform is located inside the housing and disposed at the bottom of the impact loading assembly; a first tool holder is provided on the side wall of the tool mounting platform for mounting a hobbing cutter; A sample clamping assembly, located inside the housing, is used to clamp the sample; A horizontal moving component is disposed inside the housing and located below the impact loading component; the horizontal moving component is connected to the sample clamping component to drive the sample clamping component to move horizontally; The acquisition component, located inside the housing, is used to acquire test videos and images of the hob. The impact loading component includes: A servo electric cylinder is disposed at the top of the housing; the output shaft of the servo electric cylinder is located inside the housing; the tool mounting table is disposed at the bottom of the output shaft of the servo electric cylinder; A guide assembly is disposed on the housing; the guide assembly is connected to the tool mounting table; The guiding component includes: Multiple guide bearings are disposed on the housing; Multiple guide rods are slidably disposed within multiple guide bearings; one end of each guide rod is connected to the tool mounting table. The sample clamping assembly includes: A fixed platform is disposed on the surface of the horizontally moving component; Four adjustable clamps are disposed on the surface of the fixed platform and located around the fixed platform to enclose a clamping space.

2. The experimental device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutterheads according to claim 1, characterized in that, An angle adjustment component is provided at the bottom of the first tool holder for adjusting the angle of the first tool holder.

3. The experimental device for simulating damage behavior under the impact and cutting action of shield tunnel cutterheads according to claim 2, characterized in that, A triaxial acceleration sensor and a triaxial force sensor are provided between the angle adjustment component and the tool mounting table.

4. The experimental device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutterheads according to claim 1, characterized in that, The fixed platform is provided with multiple sets of fixed slots, each set of fixed slots including two T-slots. The bottom of the adjustable clamp is provided with a through hole corresponding to the T-slot. A T-bolt is provided in the T-slot. The T-bolt passes through the through hole and cooperates with a nut to connect the adjustable clamp to the fixed platform.

5. The experimental device for simulating damage behavior under the impact and cutting action of shield tunnel cutterheads according to claim 1, characterized in that, The horizontal movement component includes: The first lead screw module is arranged laterally inside the housing; The second lead screw module is longitudinally mounted on the slider of the first lead screw module; the fixed platform is mounted on the slider of the second lead screw module.

6. The experimental device for simulating damage behavior under the impact and cutting action of tunnel boring machine cutterheads according to claim 1, characterized in that, Also includes: The second tool holder is located on the bottom wall of the tool mounting platform and is used to mount the hobbing cutter.

7. The experimental device for simulating damage behavior under the impact and cutting action of shield tunnel cutterheads according to claim 1, characterized in that, The acquisition component includes: A high-speed camera is installed on the inner wall of the housing to capture the impact and cutting process of the hob, and to collect the impact response, fracture process and motion behavior. The ultra-depth-of-field microscope is detachably installed inside the housing and is used to acquire images of the wear area of ​​the hob and the microscopic wear morphology of the hob.

Images