Three-way dislocation amount monitoring unit, monitoring device and monitoring method

Abstract

The invention discloses a three-way dislocation amount monitoring unit, device and method, and relates to the technical field of active fault monitoring equipment, and the three-way dislocation amount monitoring unit comprises a fixed part, an elastic rod, a strain sensor, a receiving module and a demodulation module. The number of the fixing pieces is two, and the two fixing pieces are used for being fixedly arranged in block bodies on the two sides of a fault structural plane correspondingly. The number of the elastic rods is six or more, and the two ends of the elastic rods are used for being connected to the two fixing pieces in a spherical hinge mode respectively. All the elastic rods are at least arranged on six different surfaces; the strain sensor is used for detecting the strain of each elastic rod; the receiving module is in communication connection with the strain sensor and is used for receiving strain information; and the demodulation module calculates the relative three-way dislocation amount of the blocks on the two sides of the fault structural plane according to the strain information. The three-way dislocation amount monitoring unit provided by the invention can detect the three-way dislocation amount of the blocks on the two sides of the fault structural plane, so that the engineering safety and the disaster early warning capability can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of active fault monitoring equipment, and particularly to a three-dimensional dislocation amount monitoring unit, a monitoring device and a monitoring method. Background Art

[0002] Under the continuous action of tectonic movement, active faults continuously undergo dislocation through complex dynamic processes, and the rock masses in the fault zone are deformed or fractured due to fault activities. In the fault zone where the geological stability is relatively poor, monitoring the fault dislocation amount is of great significance for the prevention of geological disasters and the evaluation of engineering stability. Under the action of a complex stress field, the deformations and displacements of each block in the fault zone are also different. However, the existing fault dislocation monitoring technologies are usually based on single-point measurement and cannot fully capture the three-dimensional dislocation changes between adjacent blocks in the fault zone. Summary of the Invention

[0003] The purpose of the present invention is to provide a three-dimensional dislocation amount monitoring unit, a monitoring device and a monitoring method to solve the problems existing in the above-mentioned prior art and improve the engineering safety and disaster warning ability.

[0004] To achieve the above purpose, the present invention provides the following solutions: The present invention provides a three-dimensional dislocation amount monitoring unit, including: a fixing member, an elastic rod, a strain sensor, a receiving module and a demodulation module. There are two fixing members, and the two fixing members are respectively used for being fixedly arranged in the blocks on both sides of the fault structural plane; there are six or more elastic rods, and both ends of the elastic rod are respectively used for being ball-joint connected to the two fixing members; all the elastic rods are at least arranged on six different planes; the strain sensor is used for detecting the strain of each elastic rod; the receiving module is communicatively connected to the strain sensor and is used for receiving the strain information; the demodulation module calculates the relative three-dimensional dislocation amount of the blocks on both sides of the fault structural plane according to the strain information.

[0005] Preferably, the strain sensor is an optical fiber strain sensor; the optical fiber strain sensor is laid outside the elastic rod or penetrates inside the elastic rod along the extending direction of the elastic rod; a plurality of the strain sensors are connected to a main optical fiber through a wavelength division multiplexer, and the main optical fiber is connected to the receiving module.

[0006] Preferably, the rigidity of the fixing member is greater than that of the elastic rod.

[0007] Preferably, the fixing member is in a circular ring shape, the hinge parts of the fixing member and the elastic rod are arranged in sequence along the circumferential direction, the hinge parts on the two fixing members are respectively arranged on two parallel installation planes, and the included angle between each elastic rod and the installation plane is the same.

[0008] Preferably, the demodulation module includes: a coordinate system establishment module: the coordinate system establishment module sets any one of the fixed parts as a stationary ring and the other as a moving ring, constructs a global coordinate system Oxyz with the center of the stationary ring as the origin, and constructs a local coordinate system O1x1y1z1 with the center of the moving ring as the origin; A motion constraint modeling module: according to the geometric relationship that the two ends of the six elastic rods are respectively connected to the stationary ring and the moving ring, establish a motion constraint equation between the length change of the elastic rod and the pose of the moving ring; A solution module: perform a total differential on the motion constraint equation and solve the differential equation by the Newton iteration method to obtain the relationship between the strains of the six elastic rods and the pose of the moving ring; then obtain the three-dimensional dislocation amount of the moving ring according to the strains of the six elastic rods.

[0009] Preferably, there are six elastic rods, and the motion constraint equation established by the motion constraint modeling module is as follows: Where, F i (X, ε i ) is the motion constraint equation of the moving ring, X is a six-dimensional vector representing the pose of the moving ring, where x , y , z are respectively the translation components of the moving ring on the x , y , z three axes, α , β , γ are respectively the rotation components of the moving ring rotating around the x , y , z three axes, ε i (i = 1, 2,..., 6) are the strains of the six rods, R is the rigid body rotation matrix of the moving ring, A i (i =1, 2,..., 6) are 6 points on the moving ring, B i (i = 1, 2,..., 6) are 6 points on the stationary ring; According to the implicit function theorem, the influence of the length change of the elastic rod on the pose of the moving ring is deduced as follows: Where, l0 is the original length of the rod, l i(i = 1, 2, ..., 6) are the lengths of the six elastic rods after the relative movement occurs; X, L, and F are the six-dimensional vectors of the moving ring's pose, the six-dimensional vector of the current lengths of the six elastic rods, and the motion constraint equation of the moving ring, respectively. The solving module knows the initial pose X0 of the moving ring. When relative movement occurs between the two rings, it differentiates the motion path and uses the Newton iteration method to perform incremental updates with the previous pose as the initial point. The calculation formula of the Newton iteration method is shown as follows: where n is the nth step in the differential motion path of the moving ring, and k is the number of iterations of the Newton iteration method. The convergence condition is that the motion constraint equation is less than 1 microstrain in the kth iteration, as shown in the following formula: .

[0010] The present invention also provides a three-way dislocation amount monitoring device, including the three-way dislocation amount monitoring unit as described above. Different three-way dislocation amount monitoring units are respectively arranged in the blocks at different fault structural planes.

[0011] Preferably, it further includes a conduit. The three-way dislocation amount monitoring units are sequentially fixed in the conduit along the length direction of the conduit. The conduit carries the three-way dislocation amount monitoring units and is inserted into a borehole pre-drilled in the block and fixed. When the conduit is inserted into the borehole, an annular gap for grouting is formed between the outer wall of the conduit and the borehole wall.

[0012] Preferably, the demodulation module can also calculate the relative three-way dislocation amount between any two blocks according to the three-way dislocation amounts measured by multiple three-way dislocation amount monitoring units.

[0013] The present invention also provides a three-way dislocation amount monitoring method, including: Preliminary preparation work: Determine the depth of the fault structural plane in the borehole in the fault zone by means of the core obtained through drilling and / or high-definition in-hole camera. Manufacture of the three-way dislocation amount monitoring device as described above: Mark the positions of each fault structural plane on the conduit and open holes on both sides to fix the three-way dislocation amount monitoring units. Installation of the three-way dislocation amount monitoring device: Put the conduit carrying the three-way dislocation amount monitoring units into the borehole; Grout the annular gap between the outer wall of the conduit and the borehole wall; After the slurry solidifies, a local fixing structure is formed between the outer wall of the conduit and the borehole wall, so that each three-way dislocation amount monitoring unit forms a local fixing structure with the rock mass.

[0014] The present invention has achieved the following technical effects compared with the prior art: The three-way dislocation amount monitoring unit provided by the present invention can detect the three-way dislocation amounts of the blocks on both sides of the fault structural plane. The three-way dislocation amount monitoring device provided by the present invention can detect the three-way dislocation amounts of the blocks on both sides of the fault structural plane at different positions, improving the coverage range of three-way dislocation monitoring. Therefore, the present invention can improve the engineering safety and disaster warning capabilities.

[0015] Further, in some embodiments of the present invention, an optical fiber strain sensor is used to monitor the strain of the elastic rod; and a wavelength division multiplexer and a main optical fiber are used to transmit the strain information to the receiving module in real time. The receiving module transmits the strain information to the demodulation module for calculation in real time, thereby improving the data transmission efficiency and real-time monitoring effect. It is applicable to the structural health monitoring and warning during tunnel construction and operation periods, improving the engineering safety and disaster warning capabilities. Brief Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0017] Figure 1 It is a schematic diagram of the layout of the three-way dislocation amount monitoring device provided by the embodiment of the present invention in a fault borehole; Figure 2 It is an overall schematic diagram of the fault borehole and the three-way dislocation amount monitoring device.

[0018] Figure 3 It is a schematic diagram of the three-way dislocation amount monitoring unit provided by the embodiment of the present invention; Figure 4 For Figure 3 the layout diagram of the ball joint structures on the two fixing members in

[0019] Figure 5 It is a schematic diagram before and after fault dislocation.

[0020] In the figure: 100 - fault structural plane; 200 - borehole wall; 300 - tunnel; 400 - block.

[0021] 1 - fixing member; 2 - elastic rod; 3 - ball joint structure; 4 - fixing pin; 5 - conduit; 6 - temperature compensation optical fiber; 7 - main optical fiber; 8 - wavelength division multiplexer; 10 - three-way dislocation amount monitoring unit. Detailed Embodiments

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0024] The three-dimensional dislocation, that is, the change in the three-dimensional space position, in the present invention refers to the relative position change of one block relative to another block in the three-dimensional space in two blocks. It has three-axis displacement components and rotation components around the three axes.

[0025] Next, in conjunction with Figures 1 to 5 , the embodiments of the present invention will be described.

[0026] Embodiment 1 The present invention provides a three-dimensional dislocation amount monitoring unit 10, including: a fixing member 1, an elastic rod 2, a strain sensor, a receiving module, and a demodulating module. There are two fixing members 1, and the two fixing members 1 are respectively used for being fixedly arranged in the blocks 400 on both sides of the fault structural plane 100; there are six or more elastic rods 2, and both ends of the elastic rod 2 are respectively used for being ball-joint connected to the two fixing members 1; all the elastic rods 2 are at least arranged on six different planes; the strain sensor is used for detecting the strain of each elastic rod 2; the receiving module is communicatively connected to the strain sensor and is used for receiving the strain information; the demodulating module calculates the relative three-dimensional dislocation amount of the blocks 400 on both sides of the fault structural plane 100 according to the strain information.

[0027] In the embodiment of the present invention, since both ends of the elastic rod 2 are indirectly fixedly connected to the blocks 400 on both sides of the fault structural plane 100, when the positions of the blocks 400 on both sides of the fault structural plane 100 change, it will inevitably drive the elastic rod 2 to deform. Therefore, by measuring the strain of the elastic rod 2, the deformation amount of each rod can be obtained, and then the relative displacement and angle change of the two blocks 400 can be calculated according to the geometric relationship between the elastic rod 2 and the two fixing members 1. Therefore, the three-dimensional dislocation amount monitoring unit 10 provided by the present invention can detect the three-dimensional dislocation amount of the blocks 400 on both sides of the fault structural plane 100, thereby improving the engineering safety and disaster warning ability.

[0028] In some embodiments, the strain sensor is an optical fiber strain sensor; the optical fiber strain sensor is disposed outside the elastic rod 2 or penetrates inside the elastic rod 2 along the extending direction of the elastic rod 2; a plurality of strain sensors are connected to a main optical fiber 7 through a wavelength division multiplexer 8, and the main optical fiber 7 is connected to a receiving module. In some examples, the elastic rod 2 and the optical fiber strain sensor can be fixed by means of bonding, bundling, tape winding, etc. It can be understood that the length of the optical fiber strain sensor can be long or short. If the strain of the elastic rod 2 is uniform, a shorter length can be set. If it is necessary to improve the monitoring accuracy, an optical fiber strain sensor with the same length as the elastic rod 2 can be set. Of course, for the convenience of installation, the length of the optical fiber strain sensor can also be set slightly shorter than that of the elastic rod 2.

[0029] This embodiment uses an optical fiber strain sensor to monitor the strain of the elastic rod 2; and uses the wavelength division multiplexer 8 and the main optical fiber 7 to transmit the strain information to the receiving module in real time. The receiving module transmits the strain information to the demodulation module for calculation in real time, thereby improving the data transmission efficiency and the real-time monitoring effect, and is applicable to the structural health monitoring and early warning during the tunnel construction and operation period.

[0030] The optical fiber strain sensor is preferably an optical fiber Bragg grating.

[0031] In addition to the optical fiber strain sensor used in the above embodiments, a piezoelectric strain sensor, a resistance strain gauge, etc. can also be used.

[0032] In some embodiments, the rigidity of the fixing member 1 is greater than that of the elastic rod 2. For example, the fixing member 1 can be made of stainless steel, and the elastic rod 2 can be made of aluminum alloy.

[0033] This embodiment only needs to make the elastic rod 2 deform prior to the fixing member 1, because the present invention only detects the strain information of the elastic rod 2, and only reflects the relative displacement between the two blocks 400 through the strain of the elastic rod 2.

[0034] In some embodiments, the fixing member 1 is in a circular ring shape, the hinge portions of the fixing member 1 and the elastic rod 2 are arranged in sequence along the circumferential direction, the hinge portions on the two fixing members 1 are respectively arranged on two parallel installation planes, and the angles between each elastic rod 2 and the installation plane are the same.

[0035] This embodiment is conducive to routing in the middle of the annular fixing member 1, such as the main optical fiber 7, etc. In addition, the elastic rod 2 in this embodiment is based on the principle of the parallel platform in the mechanical field. According to the calculation method of degrees of freedom, this mechanism has six degrees of freedom. Six elastic rods 2 need to measure six motion quantities on one of the fixing members 1, including the translational components in the x, y, and z directions and the three rotational components α, β, and γ of rotation about the x, y, and z axes. The six degrees of freedom of the moving fixing member 1 need to be uniquely controlled by the changes in the lengths of the six rod members. Therefore, the six rods cannot be coplanar, and for accurate and concise calculation, the lengths and inclinations of the six rods should be consistent.

[0036] In addition, the six ball joint structures 3 on one side of the fixing member 1 are B1 - B6, and the projections of the ball joint structures 3 on the other fixing member 1 are A1 - A6, which are represented by dashed lines. The ball joint structures 3 with the same subscript numbers are connected by the same elastic rod 2. For example, A1 and B1 are connected by the same elastic rod 2. It can also be said that both ends of an elastic rod 2 are A1 and B1, so that the elastic rod 2 can connect the ball joint structures 3 on the two fixing members 1 in an inclined manner and provide tensile and compressive forces in six non - coplanar axial directions respectively.

[0037] In some examples, this embodiment can also pass a temperature - compensating optical fiber 6 through the middle of the annular fixing member 1. The temperature - compensating optical fiber 6 is communicatively connected to the main optical fiber 7. The strain information detected by the temperature - compensating optical fiber 6 is not affected by the position changes of the two side blocks 400. In an ideal state, the temperature - compensating optical fiber 6 is only affected by the ambient temperature. The temperature - compensating optical fiber 6 is also a fiber Bragg grating. The temperature - compensating optical fiber 6 can be used to correct the strain information of the fiber Bragg grating on the elastic rod 2, thereby improving the monitoring accuracy.

[0038] In some embodiments, the demodulation module includes: a coordinate system establishment module: The coordinate system establishment module sets any one of the fixing members 1 as the stationary ring and the other as the moving ring, constructs a global coordinate system Oxyz with the center of the stationary ring as the origin, and constructs a local coordinate system O1x1y1z1 with the center of the moving ring as the origin; A motion constraint modeling module: According to the geometric relationship that the two ends of the six elastic rods 2 are respectively connected to the stationary ring and the moving ring, establish a motion constraint equation between the length change of the elastic rod 2 and the pose of the moving ring; A solution module: After taking the total differential of the motion constraint equation and solving the differential equation by the Newton - Raphson method, obtain the relationship between the strain of the six elastic rods 2 and the pose of the moving ring; then obtain the three - dimensional dislocation amount of the moving ring according to the strain of the six elastic rods 2.

[0039] Specifically, there are six elastic rods 2, and the motion constraint equation established by the motion constraint modeling module is shown as follows: Among them, F i (X, ε i ) is the motion constraint equation of the moving ring. X is a six-dimensional vector representing the pose of the moving ring, where x , y , z are respectively the translational components of the moving ring on the x , y , z three axes, α , β , γ are respectively the rotational components of the moving ring rotating around the x , y , z three axes. ε i (i = 1, 2,..., 6) is the strain of the six rods, R is the rigid body rotation matrix of the moving ring, A i (i =1, 2,..., 6) are 6 points on the moving ring, B i (i = 1, 2,..., 6) are 6 points on the stationary ring; According to the implicit function theorem, the influence of the length change of the elastic rod 2 on the pose of the moving ring is derived as shown in the following formula: Among them, l0 is the original length of the rod, l i (i = 1, 2,..., 6) is the length of the six elastic rods 2 after the relative motion occurs; X, L, F are respectively the six-dimensional vector of the pose of the moving ring, the six-dimensional vector of the current lengths of the six elastic rods 2, and the motion constraint equation of the moving ring; The solving module knows the initial pose X0 of the moving ring. When relative motion occurs between the two rings, it differentiates the motion path and uses the Newton iteration method to make an incremental update with the previous pose as the initial point; the calculation formula of the Newton iteration method is shown in the following formula: Among them, n is the nth step in the differential motion path of the moving ring, and k is the number of iterations of the Newton iteration method; The convergence condition is that the motion constraint equation is less than 1 microstrain in the kth iteration, as shown in the following formula: .

[0040] This embodiment provides a specific calculation method for the three-way dislocation amount.

[0041] The above embodiments provide the specific number of elastic rods 2. Since at least six elastic rods 2 are required to measure three translational and three rotational components, and more than six will result in an overdetermined kinematic equation system of the system, redundant rods will complicate the inverse kinematic equation system and may require additional numerical methods or optimization algorithms to solve, increasing the computational burden. Therefore, the purpose of using six elastic rods 2 in the above embodiments of the present invention is to simplify the algorithm or the computational difficulty while being able to measure three translational and three rotational components. It can be understood that, without considering the computational difficulty and the installation difficulty, the number of elastic rods 2 can be set to be more than 6, such as eight elastic rods 2, etc.

[0042] Embodiment 2 An embodiment of the present invention provides a three-way dislocation amount monitoring device, including the three-way dislocation amount monitoring unit 10 in the above embodiment, and different three-way dislocation amount monitoring units 10 are respectively arranged in the blocks 400 at different fault structural planes 100.

[0043] The three-way dislocation amount monitoring device provided by the present invention can detect the three-way dislocation amounts of the blocks 400 on both sides of the fault structural plane 100 at different positions, improving the coverage range of three-way dislocation monitoring.

[0044] Since this embodiment includes the three-way dislocation amount monitoring unit 10 in Embodiment 1, therefore, this embodiment includes all the advantages described in Embodiment 1 and will not be elaborated here.

[0045] In some embodiments, the embodiment of the present invention further includes a conduit 5, and the three-way dislocation amount monitoring units 10 are sequentially fixed in the conduit 5 along the length direction of the conduit 5. The conduit 5 carries the three-way dislocation amount monitoring units 10 and is inserted into a borehole pre-drilled in the block 400 and fixed. In the state where the conduit 5 is inserted into the borehole, an annular gap for grouting is formed between the outer wall of the conduit 5 and the borehole wall 200.

[0046] This embodiment uses one conduit 5 to integrate all the three-way dislocation amount monitoring units 10, which facilitates the installation of all the three-way dislocation amount monitoring units into the boreholes of the formation at one time. For the specific implementation method, see Embodiment 3.

[0047] In addition, this embodiment can cover the structural planes at different depths in the fault zone, realize continuous distributed monitoring and have a high-precision three-way dislocation amount monitoring function. Furthermore, it improves the engineering safety and disaster warning capabilities.

[0048] In some embodiments, the demodulation module can also calculate the relative three-way dislocation amount between any two blocks 400 according to the three-way dislocation amounts measured by multiple three-way dislocation amount monitoring units 10.

[0049] This embodiment achieves the purpose of calculating the relative three-dimensional dislocation amount between any two blocks 400. It can be understood that the any two blocks 400 can be two adjacent blocks 400 or two non-adjacent blocks 400.

[0050] In some embodiments, multiple strain sensors in all the three-dimensional dislocation amount monitoring units 10 are connected to the same main optical fiber 7 through a wavelength division multiplexer 8.

[0051] Specific embodiments are as Figure 2 shown. Boreholes are drilled on the wall surface of the tunnel 300. The boreholes penetrate through multiple fault structural planes 100, and then a three-dimensional dislocation amount monitoring unit 10 is arranged at each fault structural plane 100. Two fixing parts 1 of the three-dimensional dislocation amount monitoring unit 10 are respectively fixed in the blocks 400 on both sides.

[0052] Embodiment III The embodiment of the present invention provides a method for monitoring the three-dimensional dislocation amount, including: Preliminary preparation work: determining the depth of the fault structural plane 100 in the borehole in the fault zone by means of the core obtained through drilling and / or the high-definition camera in the hole; Manufacture of the three-dimensional dislocation amount monitoring device: Marking the positions of each fault structural plane 100 on the conduit 5 and opening holes on both sides for fixing the three-dimensional dislocation amount monitoring unit 10; Installation of the three-dimensional dislocation amount monitoring device: Putting the conduit 5 carrying the three-dimensional dislocation amount monitoring unit 10 into the borehole; Grouting into the annular gap between the outer wall of the conduit 5 and the borehole wall 200; After the slurry solidifies, a local fixing structure is formed between the outer wall of the conduit 5 and the borehole wall 200, so that each three-dimensional dislocation amount monitoring unit 10 forms a local fixing structure with the rock mass.

[0053] In some embodiments, the annular fixing part 1 is anchored to the conduit 5 through a fixing pin 4. In some examples, since the ultimate goal is to anchor the fixing part 1 in the rock mass block 400, one end of the fixing pin 4 penetrates through the fixing part 1 and the conduit 5, and the other end extends from the outer wall of the conduit 5 into the annular gap. In this way, after grouting, the fixing pin 4 can be anchored by the solidified slurry, thereby enhancing the connection stability between the fixing part 1 and the block 400. Furthermore, the displacement change of the block 400 can be accurately reflected on the fixing part 1, and the fixing part 1 then accurately drives the elastic rod 2 to deform, ultimately achieving the purpose of improving the monitoring accuracy.

[0054] In the present invention, specific examples are used to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A three-way dislocation amount monitoring unit, characterized in that: Comprising: Fixing members, two of which are provided, and the two fixing members are respectively used for being fixedly arranged in the blocks on both sides of the fault structural plane; Elastic rods, six or more of which are provided, and both ends of the elastic rods are respectively used for being ball-joint connected to the two fixing members; all the elastic rods are arranged on at least six different planes; Strain sensors, which are used for detecting the strain of each elastic rod; Receiving module, which is communicatively connected to the strain sensors and is used for receiving the strain information; Demodulation module, which calculates the relative three-dimensional dislocation amount of the blocks on both sides of the fault structural plane according to the strain information.

2. The three-way dislocation amount monitoring unit according to claim 1, characterized in that: The strain sensors are fiber optic strain sensors; the fiber optic strain sensors are laid outside the elastic rods or penetrate through the elastic rods along the extending direction of the elastic rods; a plurality of the strain sensors are connected to a main optical fiber through a wavelength division multiplexer, and the main optical fiber is connected to the receiving module.

3. The three-way dislocation amount monitoring unit according to claim 1, wherein: The rigidity of the fixing members is greater than that of the elastic rods.

4. The three-way dislocation amount monitoring unit according to claim 1, wherein: The fixing members are in a circular ring shape, and the hinge parts of the fixing members and the elastic rods are arranged in sequence along the circumferential direction. The hinge parts on the two fixing members are respectively arranged on two parallel installation planes, and the included angles between each elastic rod and the installation plane are the same.

5. The three-way dislocation amount monitoring unit according to claim 4, characterized in that: The demodulation module includes: a coordinate system establishment module: the coordinate system establishment module sets any one of the fixing members as a stationary circular ring and the other as a moving circular ring, constructs a global coordinate system Oxyz with the center of the stationary circular ring as the origin, and constructs a local coordinate system O1x1y1z1 with the center of the moving circular ring as the origin; Motion constraint modeling module: according to the geometric relationship that both ends of six elastic rods are respectively connected to the stationary circular ring and the moving circular ring, establishes a motion constraint equation between the length change of the elastic rods and the pose of the moving circular ring; Solution module: after taking the total differential of the motion constraint equation, solves the differential equation by the Newton iteration method to obtain the relationship between the strain of the six elastic rods and the pose of the moving circular ring; then obtains the three-dimensional dislocation amount of the moving circular ring according to the strain of the six elastic rods.

6. The three-way dislocation amount monitoring unit according to claim 5, wherein: Six elastic rods are provided, and the motion constraint equation established by the motion constraint modeling module is shown as the following formula: Among them, F i (X, ε i ) is the moving ring motion constraint equation, X is a six-dimensional vector representing the pose of the moving ring, where x , y , z are respectively the translational components of the moving ring on the x , y , z three axes, α , β , γ are respectively the rotational components of the moving ring rotating around the x , y , z three axes, ε i (i = 1, 2,..., 6) is the strain of the six rods, R is the rigid body rotation matrix of the moving ring, A i (i = 1, 2,..., 6) are 6 points on the moving ring, B i (i = 1, 2,..., 6) are 6 points on the stationary ring; According to the implicit function theorem, the influence of the length change of the elastic rods on the pose of the moving circular ring is deduced as shown in the following formula: where \(l_0\) is the original length of the rod, and \(l\) i i (\(i = 1, 2, \cdots, 6\)) are the lengths of the six elastic rods after the relative motion occurs; \(X\), \(L\), and \(F\) are the six-dimensional vectors of the pose of the moving ring, the six-dimensional vectors of the current lengths of the six elastic rods, and the motion constraint equations of the moving ring, respectively; The solution module knows the initial pose X0 of the moving circular ring. When the two circular rings move relatively, the motion path is differentiated, and the incremental update is made with the previous pose as the initial point by the Newton iteration method; the calculation formula of the Newton iteration method is shown as the following formula: Wherein, n is the nth step in the differential motion path of the moving circular ring, and k is the number of iterations of the Newton iteration method; The convergence condition is that the motion constraint equation is less than 1 microstrain in the kth iteration, as shown in the following formula: 。 7. A three-way dislocation amount monitoring device, characterized in that: Including a plurality of three-dimensional dislocation amount monitoring units according to any one of claims 1 to 6, and different three-dimensional dislocation amount monitoring units are respectively arranged in the blocks at different fault structural planes.

8. The three-way dislocation amount monitoring device according to claim 7, wherein: It further includes a conduit, and the three-way dislocation amount monitoring unit is sequentially fixed in the conduit along the length direction of the conduit. The conduit carries the three-way dislocation amount monitoring unit and is inserted into a borehole pre-drilled in a block and fixed. When the conduit is inserted into the borehole, an annular gap for grouting is formed between the outer wall of the conduit and the borehole wall.

9. The three-way dislocation amount monitoring device according to claim 7, characterized in that: The demodulation module can also calculate the relative three-way dislocation amount between any two blocks according to the three-way dislocation amounts measured by multiple three-way dislocation amount monitoring units.

10. A method for monitoring the three-way dislocation amount, characterized in that: It includes: Preliminary preparation work: determining the depth of the fault structural plane in the fault zone in the borehole by means of the core obtained through drilling and / or high-definition in-hole camera; Manufacture of the three-way dislocation amount monitoring device according to any one of claims 7 to 9: marking the positions of each fault structural plane on the conduit and opening holes on both sides for fixing the three-way dislocation amount monitoring unit; Installation of the three-way dislocation amount monitoring device: putting the conduit carrying the three-way dislocation amount monitoring unit into the borehole; grouting into the annular gap between the outer wall of the conduit and the borehole wall; after the slurry solidifies, a local fixing structure is formed between the outer wall of the conduit and the borehole wall, so that each three-way dislocation amount monitoring unit forms a local fixing structure with the rock mass.

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