A tunnel surrounding rock disturbance and deformation monitoring system and method

Abstract

This invention relates to the field of tunnel construction monitoring technology, specifically a monitoring system and method for monitoring disturbance and deformation of surrounding rock in milling tunnels. The system includes: visually inspecting the rock surface at the excavation front and adjacent tunnel walls at a reference and current time; extracting surrounding rock boundary points and surface points to form a reference and current set of boundary points and a set of surface points; projecting the boundary point sets onto the same unfolded surface, with adjacent segments of zero and negative value points forming the cutting front edge zone, and connecting the boundary points corresponding to negative value points to form the cutting front edge boundary; matching the reference surface points with the current surface point set, with those outside the cutting front edge boundary and adjacent points remaining unchanged forming the retained surface point set, and those not included in the retained surface point set on the rear side forming the newly exposed surface point set; accumulating the retreat distance along the cutting front edge boundary to obtain the cutting retreat amount, and calculating the coordinate difference between the corresponding points of the retained surface points to obtain the retained surface deformation amount; this invention solves the problem in existing milling monitoring where cutting retreat, newly exposed surface deformation, and retained surface deformation are mixed, making it difficult to effectively separate changes in surrounding rock removal and disturbance deformation.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction monitoring technology, specifically a monitoring system and method for monitoring disturbance and deformation of surrounding rock in milling tunnels. Background Technology

[0002] In monitoring the surrounding rock during milling tunnel construction, existing technologies mainly identify abnormal changes in the surrounding rock during the excavation process to provide a basis for support arrangements and construction adjustments. Current processing methods often involve visual inspection of the tunnel face and adjacent tunnel walls at adjacent work times to obtain images, contours, or surface coordinate information, followed by before-and-after registration and difference comparison to extract the amount of surrounding rock change.

[0003] However, under the operating conditions of continuous cutting along the contour of the tunnel face by the milling head, the cutting boundary continues to advance, the surface layer of the surrounding rock is continuously removed, and new rock surfaces are continuously exposed. At the same time, the equipment vibration is significant, the operation transition interval is short, and the monitoring results need to be used for on-site judgment in a short period of time. Under these conditions, the difference between the two visual inspection results includes not only the boundary retreat corresponding to the removed area and the geometric changes of the newly exposed surface, but also the displacement, bulging or cracking generated by the uncut surrounding rock itself. As a result, once the image or contour changes, the existing comparison results cannot determine whether the change comes from milling removal or from the deformation of the surrounding rock entity. This leads to the confusion between surrounding rock disturbance identification and deformation judgment, making it difficult to form a monitoring conclusion that can directly correspond to on-site handling.

[0004] Therefore, how to distinguish the surface removal changes caused by milling from the disturbance and deformation changes of the surrounding rock itself based on visual inspection results during the construction of milling tunnels is the technical problem to be solved in this application. Summary of the Invention

[0005] To overcome the aforementioned deficiencies of the prior art, the present invention provides a monitoring system and method for monitoring disturbance and deformation of surrounding rock in milling tunnels. By separating and calculating the boundary retreat, newly exposed surface and retained surface deformation in the visual inspection results before and after milling, the present invention solves the problems mentioned in the background art.

[0006] This invention is achieved using the following technical solution: A method for monitoring disturbance and deformation of surrounding rock in milling tunnels includes the following steps: S1. At the reference time, visual inspection is performed on the rock surface at the front end of the excavation and the adjacent tunnel wall to extract the surrounding rock boundary points and surrounding rock surface points, forming a reference boundary point set and a reference surface point set. At the current time, visual inspection is performed on the rock surface at the front end of the excavation and the adjacent tunnel wall to extract the surrounding rock boundary points and surrounding rock surface points, forming a current boundary point set and a current surface point set. S2. Project the reference boundary point set and the current boundary point set onto the same unfolding surface, calculate the front and rear distances point by point along the unfolding direction, determine the adjacent coordinate segments between the zero point and the negative value point as the cutting front edge zone, and connect the current boundary points corresponding to the negative value points to form the cutting front edge boundary. S3. Search for corresponding points in the current surface point set for the reference surface point set. Determine the surface points located outside the cutting front boundary and whose adjacency relationship remains unchanged as the retained surface point set. Determine the current surface points located behind the cutting front boundary and not entering the retained surface point set as the newly exposed surface point set. S4. Calculate the back distance from the reference boundary point set to the current boundary point set point by point along the cutting front boundary and accumulate them to obtain the cutting back amount. Calculate the front and back coordinate differences for the corresponding points in the retained surface point set to obtain the retained surface deformation amount. S5. Determine the new exposure range based on the newly exposed surface point set, determine the cutting retreat amount and the newly exposed range as surface removal changes, determine the retained surface deformation amount as disturbance deformation changes, and output the surrounding rock monitoring results according to the cutting front boundary.

[0007] Further, step S1 includes: S1-1. The visual detection results at the reference time and the visual detection results at the current time are spatially restored according to the correspondence between pixel position and spatial position to form a reference spatial point set and a current spatial point set. S1-2. The reference spatial point set and the current spatial point set are divided into multiple angular directions along the circumference, starting from the center point of the rock surface at the front end of the excavation. The spatial points in each angular direction are sorted according to their distance from the center point of the rock surface at the front end of the excavation. The last spatial point in the sorting is taken as the surrounding rock boundary point to form the reference boundary point set and the current boundary point set. S1-3. Extract spatial points located between adjacent surrounding rock boundary points from the reference spatial point set and the current spatial point set, respectively, as surrounding rock surface points to form the reference surface point set and the current surface point set.

[0008] Further, step S2 includes: S2-1. Project the reference boundary point set and the current boundary point set onto the same unfolding surface according to the tunnel axial coordinate and circumferential coordinate respectively, and arrange them according to the circumferential coordinate to form a reference unfolding point column and a current unfolding point column; S2-2. Take corresponding points for the reference unfolded point series and the current unfolded point series according to the same circumferential position, calculate the current axial coordinate of each corresponding point and subtract the reference axial coordinate to obtain the axial difference, and form an axial difference sequence. S2-3. Extract the adjacent coordinate segments between points with an axial difference of zero and points with an axial difference less than zero from the axial difference sequence to form the cutting front edge zone; S2-4. Extract the current unfolded points corresponding to the points with axial differences less than zero in the cutting front zone, and connect them according to the circumferential coordinates to form the cutting front boundary.

[0009] Further, step S3 includes: S3-1. Extract reference surface points located outside the cutting front boundary from the reference surface point set, extract current surface points located outside the cutting front boundary from the current surface point set, and record the point coordinates, adjacent point order, and adjacent edge order for each reference surface point and each current surface point respectively. S3-2. Calculate the point coordinate difference between each reference surface point and all current surface points. Arrange the current surface points in ascending order of point coordinate difference. Read the current surface points in the arrangement result in sequence. Determine the first current surface point with the same adjacent point order and adjacent edge order as the corresponding reference surface point. If none of the current surface points in the arrangement result satisfy the requirements of the same adjacent point order and adjacent edge order, determine the corresponding reference surface point as a non-corresponding reference surface point. S3-3. Summarize the corresponding points of the reference surface points according to the current surface points. When one current surface point corresponds to one reference surface point, the current surface point is determined as a reserved surface point. When one current surface point corresponds to two or more reference surface points, read the point coordinate difference for each corresponding reference surface point, take the current surface point corresponding to the first position of the point coordinate difference sorted by the first position, determine it as a reserved surface point, and determine the remaining reference surface points as uncorresponding reference surface points. Gather all the reserved surface points to form the reserved surface point set. S3-4. Read the positional and adjacency relationships of the current surface points that have not entered the set of retained surface points one by one. When the current surface point is located behind the cutting front boundary and has an adjacent edge with the surface points in the set of retained surface points, the current surface point is determined as a surface point to be divided. When the current surface point is located outside the cutting front boundary or there is no adjacent edge between the current surface point and the surface points in the set of retained surface points, stop the current surface point division. S3-5. Calculate the point coordinate difference between each surface point to be divided and all reference surface points, and compare the order of adjacent points and adjacent edges respectively. If there is no reference surface point among all reference surface points that simultaneously satisfies the following conditions: the point coordinate difference is first in the sorting, the adjacent point order is consistent, and the adjacent edge order is consistent, then the surface point to be divided is determined as the newly exposed surface point. All newly exposed surface points are collected to form the set of newly exposed surface points. If there is a reference surface point among all reference surface points that simultaneously satisfies the following conditions: the point coordinate difference is first in the sorting, the adjacent point order is consistent, and the adjacent edge order is consistent, then stop dividing the surface point to be divided.

[0010] Further, step S4 includes: S4-1. Extract the current boundary points in the current boundary point set sequentially along the cutting front boundary, connect adjacent current boundary points to form a current boundary line segment group, and establish a current normal line at each current boundary point according to the bisector of the included angle between two adjacent current boundary line segments. S4-2. Extract the intersection points of the reference boundary line segment group formed by the reference boundary point set on each current normal line and the current normal line. Determine the distance between the intersection point and the current boundary point as the boundary retreat distance. Add up all the boundary retreat distances according to the arrangement order of the current boundary points on the cutting front boundary to form the cutting relief amount. S4-3. Extract adjacent edges from each retained surface point and the corresponding reference surface point in the retained surface point set to form a current adjacent edge group and a reference adjacent edge group. Calculate the edge length arrangement order and the edge angle arrangement order for the current adjacent edge group and the reference adjacent edge group respectively. When the edge length arrangement order and the edge angle arrangement order are consistent, the retained surface point is determined as a displacement point. When the edge length arrangement order or the edge angle arrangement order is inconsistent, the retained surface point is determined as a deformation point. S4-4. Calculate the front and rear coordinate differences between the retained surface point and the reference surface point for the displacement point and deformation point respectively, and collect all the front and rear coordinate differences according to the adjacency relationship of the retained surface point in the set of retained surface points to form the retained surface deformation amount.

[0011] Further, step S5 includes: S5-1. Calculate the distance between each newly exposed surface point in the newly exposed surface point set and the boundary of the cutting front edge. Take the boundary point corresponding to the first point in the sorting of the distance between the points as the assigned boundary point, and gather the newly exposed surface points according to the assigned boundary points to form the newly exposed range corresponding to each boundary point. S5-2. According to the arrangement order of each boundary point in the cutting front boundary, the cutting retraction amount is allocated to each boundary point, and the cutting retraction amount corresponding to each boundary point is merged with the newly exposed range to form the surface removal change. The remaining surface deformation amount is allocated to each boundary point according to the adjacency relationship between the set of remaining surface points and the cutting front boundary to form the disturbance deformation change. S5-3. According to the arrangement order of each boundary point in the cutting front boundary, write the surface removal change and the disturbance deformation change into each boundary point to form the surrounding rock monitoring result.

[0012] A monitoring system for disturbance and deformation of surrounding rock in milled tunnels, employing the method described in this invention, includes: The time-series acquisition module is used to perform visual inspection of the rock surface at the excavation front end and the adjacent tunnel wall at the reference time, extract the surrounding rock boundary points and surrounding rock surface points to form the reference boundary point set and the reference surface point set. At the current time, it performs visual inspection of the rock surface at the excavation front end and the adjacent tunnel wall, extracts the surrounding rock boundary points and surrounding rock surface points to form the current boundary point set and the current surface point set. The cutting front identification module is used to project the reference boundary point set and the current boundary point set onto the same unfolding surface, calculate the front-to-back distance point by point along the unfolding direction, determine the adjacent coordinate segments between the zero-point and the negative-point front-to-back distance as the cutting front edge zone, and connect the current boundary points corresponding to the negative points to form the cutting front edge boundary. The surface sorting module is used to search for corresponding points in the current surface point set for the reference surface point set, determine the surface points located outside the cutting front boundary and whose adjacency relationship remains unchanged as the retained surface point set, and determine the current surface points located behind the cutting front boundary and not entering the retained surface point set as the newly exposed surface point set. The retreat calculation module is used to calculate and accumulate the retreat distance from the reference boundary point set to the current boundary point set along the cutting front boundary point by point to obtain the cutting retreat amount, and to calculate the front and rear coordinate difference for the corresponding points in the retained surface point set to obtain the retained surface deformation amount. The result output module is used to determine the new exposure range based on the newly exposed surface point set, determine the cutting retreat amount and the new exposure range as surface removal changes, determine the retained surface deformation amount as disturbance deformation changes, and output the surrounding rock monitoring results according to the cutting front boundary.

[0013] This invention provides a monitoring system and method for monitoring disturbance and deformation of surrounding rock in milled tunnels, which has the following advantages compared with the prior art: 1. By calculating the cutting relief amount, the newly exposed area and the deformation amount of the retained surface separately, and writing them as surface removal change and disturbance deformation change respectively, the problem of the mixing of milling removal and surrounding rock deformation can be relatively improved, making the monitoring results easier to respond to on-site handling.

[0014] 2. By writing the reference boundary point set and the current boundary point set into the same unfolded surface, and using the axial difference to extract the cutting front zone and the cutting front boundary, the position aliasing in the boundary advance identification can be relatively reduced, so that the subsequent boundary retreat calculation has a direct boundary basis.

[0015] 3. By searching for the corresponding points of the reference surface points in the current surface point set and combining the adjacency relationship to separate the retained surface point set and the newly exposed surface point set, the mixing of newly exposed surfaces and the original retained surfaces can be relatively suppressed, making the distinction between retained surfaces and newly exposed surfaces easier to call in subsequent calculations.

[0016] 4. By calculating the boundary retreat distance point by point along the cutting front boundary and accumulating it to form the cutting retreat amount, the retreat situation at different boundary positions can be written out separately, thereby relatively improving the segmented judgment ability of the cutting advance degree.

[0017] 5. By extracting the difference in coordinates between the points on the retained surface and aggregating them according to their adjacency to form the deformation of the retained surface, the displacement and local shape changes of the uncut area can be written into the same result, thereby relatively improving the reflection effect of the surrounding rock disturbance changes.

[0018] 6. By writing the surface removal changes and disturbance deformation changes according to the arrangement order of each boundary point in the cutting front boundary, the surrounding rock monitoring results along the boundary can be formed, which facilitates the reading and comparison of local sections and improves the on-site monitoring display and interpretation. Attached Figure Description

[0019] Figure 1 This is a flowchart of the method of the present invention.

[0020] Figure 2 This is a schematic diagram of the system modules of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] See attached document Figure 1-2 The present invention provides a method for monitoring disturbance and deformation of surrounding rock in milling tunnels, comprising: S1. At the reference time, visual inspection is performed on the rock surface at the front end of the excavation and the adjacent tunnel wall to extract the surrounding rock boundary points and surrounding rock surface points, forming a reference boundary point set and a reference surface point set. At the current time, visual inspection is performed on the rock surface at the front end of the excavation and the adjacent tunnel wall to extract the surrounding rock boundary points and surrounding rock surface points, forming a current boundary point set and a current surface point set.

[0023] This implementation method is used to convert the visual detection results at the reference time and the current time into the basic data required for subsequent cutting front identification and surface segmentation. The processing objects include the reference spatial point set, the current spatial point set, the reference boundary point set, the current boundary point set, the reference surface point set, and the current surface point set. During processing, the visual detection results are first restored to spatial points, and then the surrounding rock boundary points are extracted circumferentially starting from the center point of the rock surface at the excavation front. Subsequently, the surrounding rock surface points are extracted within the range enclosed by the surrounding rock boundary points. In this way, the original visual detection results are converted into boundary point sets and surface point sets, providing the input basis for the subsequent calculation of cutting front boundary, retained surface point set, newly exposed surface point set, cutting retreat amount, and retained surface deformation amount.

[0024] The implementation process specifically includes the following steps: S1-1. Spatial reconstruction is performed on the visual detection results at the reference time and the current time. The visual detection results are generated by synchronous acquisition using a binocular camera. The reference time corresponds to the acquisition results before the start of a milling cycle, and the current time corresponds to the acquisition results after a milling advance in the same excavation section. Both acquisitions cover the same excavation front rock surface and adjacent tunnel wall area. During spatial reconstruction, the pixel positions of the left view and the right view are first mapped according to the intrinsic parameters of the binocular camera and the extrinsic parameters between the binocular cameras to obtain corresponding pixel pairs. Then, the spatial coordinates are calculated based on the disparity value of the corresponding pixel pairs to form spatial points. The correspondence between pixel positions and spatial positions is determined by... Based on the calibration results of the calibration board, each pixel position corresponds to a line of sight after calibration, and the intersection of two lines of sight is used as the spatial point position. The reference spatial point set is formed according to this process at the reference time, and the current spatial point set is formed according to the same process at the current time. In order to avoid writing dust, flying debris and equipment surface into the spatial point set, after spatial restoration, it is also necessary to delete spatial points that fall within the equipment installation area and spatial points that do not fall within the observation range of the rock surface at the front end of the excavation and the adjacent tunnel wall. Taking the binocular camera set at the front end of the milling equipment as an example, the left view and the right view are acquired at the same trigger time. After the extraction of the same pixel pair is completed, the pixel points can be restored to three-dimensional spatial points, and thus the reference spatial point set and the current spatial point set are obtained.

[0025] S1-2. Extract the surrounding rock boundary points from the reference spatial point set and the current spatial point set respectively; the center point of the rock surface at the excavation front end is determined by the equipment installation posture, specifically: read the installation direction of the visual inspection device, project the observation axis of the visual inspection device onto the spatial point area corresponding to the rock surface at the excavation front end, and take the intersection of the observation axis and the spatial point area corresponding to the rock surface at the excavation front end as the center point of the rock surface at the excavation front end; then, divide multiple angular directions along the circumference starting from the center point of the rock surface at the excavation front end; in one embodiment, the circumference is divided into 360 angular directions, each angular direction corresponding to one degree of angle width; for each angular direction, extract the spatial points falling within that angular direction, and calculate the distance between each spatial point and the center point of the rock surface at the excavation front end. The distances are calculated and sorted in ascending order. The last spatial point in the sorted list is taken as the boundary point of the surrounding rock in that angular direction. After extracting all angular directions according to the same rule, a baseline boundary point set and a current boundary point set are formed. The reason for using this method is that the boundary points of the surrounding rock are located at the outer contour of the rock surface at the front end of the excavation. In the same angular direction, they are located at a position farther away from the center point of the rock surface at the front end of the excavation. Therefore, sorting by distance and taking the last spatial point in the sorted list can separate the boundary position from the spatial point set. If there are no spatial points in a certain angular direction, the two nearest existing surrounding rock boundary points on both sides of that angular direction are read, and a supplementary point is inserted according to the angular position. The supplementary point is only used to maintain the order of the boundary points and is not written into the surrounding rock surface point extraction process.

[0026] S1-3. Extract surrounding rock surface points from the reference spatial point set and the current spatial point set respectively. Specifically, first connect adjacent surrounding rock boundary points in the reference boundary point set in circumferential order to form a reference closed boundary line; connect adjacent surrounding rock boundary points in the current boundary point set in the same way to form the current closed boundary line; then project the reference spatial point set onto a local section perpendicular to the observation axis, read the spatial points that fall inside the reference closed boundary line after projection, and delete the surrounding rock boundary points from the reference boundary point set. Determine the remaining spatial points as reference surface points to form the reference surface point set; then... The spatial point set is projected, sieved, and boundary points are deleted according to the same rules to form the current surface point set. Here, the surrounding rock surface points only include spatial points located inside the area enclosed by the surrounding rock boundary points, and do not include the surrounding rock boundary points themselves. Thus, the boundary point set is used exclusively for boundary positioning, and the surface point set is used exclusively for surface correspondence and deformation calculation. Taking the rock surface at the front end of the excavation as an example with an approximately closed contour, a closed boundary line is formed by connecting the surrounding rock boundary points in the circumferential direction. Any spatial point that falls inside the closed boundary line after projection is taken as the surrounding rock surface point. Spatial points located on the closed boundary line are still retained in the boundary point set and are no longer written into the surface point set.

[0027] In this implementation method, the visual detection results are sequentially converted into spatial points, surrounding rock boundary points, and surrounding rock surface points. Subsequent steps do not require re-extracting the basic objects from the original image; instead, they directly continue to perform cutting front boundary recognition, retained surface point extraction, and newly exposed surface point extraction on the baseline boundary point set, current boundary point set, baseline surface point set, and current surface point set. The boundary extraction method using the center point of the rock surface at the excavation front and circumferential sorting ensures a clear source of surrounding rock boundary points. The surface extraction method using sieving within closed boundary lines ensures a clear range of values ​​for surrounding rock surface points. The method of acquiring data at the baseline time and the current time for the same excavation section ensures a clear temporal correspondence between point sets. In practical applications: First, before the start of the milling cycle, images of the rock surface at the excavation front and the adjacent tunnel walls are acquired. After spatial restoration, a reference spatial point set is obtained. Then, the center point of the rock surface at the excavation front is determined according to the intersection of the observation axis and the rock surface. The reference boundary point set is extracted in circumferential order, and the reference surface point set is extracted within the area enclosed by the reference boundary point set. After completing one milling advance in the same excavation section, images are acquired again, and the current spatial point set, current boundary point set, and current surface point set are obtained in the same way. Then, these two sets of point sets are sent to subsequent steps for cutting front identification, cutting front boundary formation, retained surface point set formation, newly exposed surface point set formation, and output of surrounding rock monitoring results.

[0028] S2. Project the reference boundary point set and the current boundary point set onto the same unfolding surface, calculate the front and rear distances point by point along the unfolding direction, determine the adjacent coordinate segments between the zero point and the negative point as the cutting front edge zone, and connect the current boundary points corresponding to the negative points to form the cutting front edge boundary.

[0029] This implementation method establishes a directly comparable positional representation between the reference boundary point set and the current boundary point set, and extracts the cutting front edge zone and cutting front edge boundary based on this. During processing, the reference boundary point set and the current boundary point set are first written into the same unfolding surface, and then a reference unfolding point sequence and a current unfolding point sequence are formed according to the circumferential position. Subsequently, the axial difference is calculated at the same circumferential position, and the coordinate segment transitioning from zero to negative value is separated from the axial difference sequence to determine the cutting front edge zone. Finally, the corresponding current unfolding points are extracted from the cutting front edge zone and connected to form the cutting front edge boundary. After this processing, the original three-dimensional boundary points are transformed into an ordered point sequence unfolded along the tunnel axis and circumference, and the subsequent calculation of cutting relief and surface removal changes can be directly unfolded along the cutting front edge boundary.

[0030] The implementation process includes the following steps: S2-1. Project the reference boundary point set and the current boundary point set onto the same unfolded surface, and form a point series according to the circumferential coordinates. Specifically, first use the tunnel design centerline direction as the axial reference direction, and then use the circumferential direction of the section where the center point of the rock face at the excavation front is located as the circumferential reference direction. For each boundary point in the reference boundary point set, read the spatial line connecting the boundary point to the center point of the rock face at the excavation front. Record the projection length of the spatial line on the tunnel axis as the axial coordinate, and record the included angle corresponding to the rotation of the spatial line around the center point of the rock face at the excavation front to the circumferential reference direction as the circumferential coordinate. Calculate the axial and circumferential coordinates for each boundary point in the current boundary point set in the same way. After coordinate calculation, the axial coordinate is used as one axis of the unfolded surface, and the circumferential coordinate is used as the other axis. The reference boundary point set and the current boundary point set are written into the unfolded surface to obtain the reference unfolded point and the current unfolded point. Then, the reference unfolded point and the current unfolded point are arranged in ascending order of circumferential coordinate to form the reference unfolded point sequence and the current unfolded point sequence. If the circumferential coordinate crosses the starting angle position, the unfolding is restarted with zero degrees as the circumferential starting point, so that the reference unfolded point sequence and the current unfolded point sequence are arranged under the same circumferential starting point. Taking a circular or near-circular tunnel cross section as an example, each boundary point forms a boundary trajectory unfolded along the circumference in the unfolded surface, and subsequent point comparisons are all performed on this unfolded trajectory.

[0031] S2-2. For the reference unfolded point series and the current unfolded point series, corresponding points are selected according to the same circumferential position, forming an axial difference sequence. Specifically, each reference unfolded point in the reference unfolded point series and each current unfolded point in the current unfolded point series are read first, using the circumferential coordinates as the basis for point selection. When the reference unfolded point series and the current unfolded point series share the same circumferential coordinate at a certain circumferential position, the reference unfolded point and the current unfolded point at that position are directly selected as a pair of corresponding points. When a certain circumferential position has a point in only one point series and not in another, the two nearest unfolded points on either side of that circumferential position are read from the point series where no point exists. For each set of points, insert a supplementary point at the circumferential position by connecting the two points, and then combine the supplementary point with the original point to form a corresponding point. For each set of corresponding points, calculate the axial coordinate of the current unfolded point minus the axial coordinate of the reference unfolded point to obtain the axial difference value corresponding to that circumferential position. Arrange the axial differences at all circumferential positions according to the circumferential coordinates to form an axial difference value sequence. If the current unfolded point is located in the backward direction of the reference unfolded point, the axial difference value is negative. If the current unfolded point and the reference unfolded point are at the same axial position, the axial difference value is zero. Through this process, the reference unfolded point sequence and the current unfolded point sequence obtain a set of directly calculable axial differences at each circumferential position.

[0032] S2-3. Extract the cutting front edge zone from the axial difference sequence. In specific processing, read each axial difference value in the axial difference sequence sequentially in ascending order of circumferential coordinates, and compare the sign states of adjacent axial differences. When the axial difference at a circumferential position is zero, and the axial difference at the next adjacent circumferential position is negative, the coordinate segment between these two circumferential positions is recorded as a cutting front edge transition segment. When the axial difference at a circumferential position is negative, and the axial difference at the previous adjacent circumferential position is zero, the coordinate segment between these two circumferential positions is also recorded as a cutting front edge. Transition segment; after collecting all the leading edge transition segments according to their circumferential positions, the cutting leading edge zone is obtained; if multiple leading edge transition segments appear in the axial difference sequence, they are retained separately and recorded in segments according to their circumferential positions; if the two ends of a certain leading edge transition segment correspond to zero and negative values ​​respectively, then the leading edge transition segment represents the transition position of the milling boundary from the non-retreating area to the retreating area; taking the case where the local contour has been advanced by milling as an example, in the circumferential position where no boundary retreat has occurred, the axial difference remains zero, and in the circumferential position where boundary retreat has occurred, the axial difference turns into a negative value. Therefore, the area where the zero value and the negative value are adjacent is the area where the cutting leading edge zone is located.

[0033] S2-4. Extract the current unfolded points corresponding to points with axial differences less than zero in the cutting front zone and form the cutting front boundary. Specifically, first read the circumferential positions covered by the cutting front zone, then extract the current unfolded points corresponding to points with axial differences less than zero at each circumferential position. If multiple points with axial differences less than zero exist within a certain cutting front zone, take the current unfolded point located at the front of the cutting front zone in the circumferential coordinates as the boundary point. If only one point with an axial difference less than zero exists within a certain cutting front zone, directly take that current unfolded point as the boundary point. Sort all boundary points in ascending order of their circumferential coordinates, and then... The next straight line connects adjacent boundary points to form the cutting front boundary. When the circumferential coordinate reaches the end of the unfolded surface, the last boundary point is connected to the first boundary point in the circumferential back-connection direction to keep the cutting front boundary closed. The cutting front boundary formed here comes from the current unfolded point set. Therefore, when calculating the boundary retreat distance along the cutting front boundary, it can be directly connected back to the current boundary point set. Taking the local cutting advance on one side of the rock surface at the front of the excavation as an example, the cutting front zone will be concentrated in the corresponding circumferential section. After extracting the current unfolded point corresponding to the negative value point, a forward-moved cutting front boundary can be formed in this section.

[0034] In this implementation method, the reference boundary point set and the current boundary point set are transformed into an ordered sequence of points within the same unfolded plane, thereby forming an axial difference sequence. The cutting front zone and the cutting front boundary are also distinguished accordingly. Subsequent steps do not require re-determining the cutting boundary position from the three-dimensional boundary points. Instead, the boundary retreat distance calculation, the attribution of the newly exposed area, and the writing of the surrounding rock monitoring results are directly performed along the cutting front boundary. After this processing, the reference boundary point set and the current boundary point set are first placed in the same unfolded plane and arranged in the same order. Then, the non-retreat position and the retreat position are separated by the axial difference. The positions adjacent to the zero point and the negative point are the cutting front zone. The current unfolded points corresponding to the negative points are further connected to form the cutting front boundary. Subsequently, the boundary retreat distance can be calculated along this boundary.

[0035] In practical applications: First, the reference boundary point set and the current boundary point set are written into the unfolded surface composed of axial coordinates and circumferential coordinates, respectively. Then, a reference unfolded point sequence and a current unfolded point sequence are formed according to the circumferential coordinates. Subsequently, the reference unfolded point and the current unfolded point are read at each circumferential position, and the difference between the current axial coordinate and the reference axial coordinate is calculated to form an axial difference sequence. Then, the coordinate segments adjacent to zero and negative values ​​are separated from the axial difference sequence to form the cutting front zone. The current unfolded point corresponding to the negative value point is extracted in the cutting front zone. Finally, these current unfolded points are connected according to the circumferential coordinates to obtain the cutting front boundary. The cutting front boundary is then sent to subsequent steps for the calculation of cutting relief, the distribution of surface removal changes, and the generation of surrounding rock monitoring results.

[0036] S3. Search for corresponding points in the current surface point set for the reference surface point set. Surface points located outside the cutting front boundary and whose adjacency remains unchanged are determined as the retained surface point set. Current surface points located behind the cutting front boundary and not entering the retained surface point set are determined as the newly exposed surface point set.

[0037] This implementation method is used to separate a retained surface point set and a newly exposed surface point set between a reference surface point set and a current surface point set. During processing, surface points located outside the cutting front boundary are first extracted from both the reference and current surface point sets. Point coordinates, adjacent point order, and adjacent edge order are established for each surface point. Then, starting from the reference surface point, corresponding points are searched point by point in the current surface point set. First, corresponding points to the reference surface point are formed. Then, conflicts where multiple reference surface points point to the same current surface point are resolved, resulting in a retained surface point set. Subsequently, surface points located behind the cutting front boundary and adjacent to retained surface points are separated from the current surface points that have not entered the retained surface point set. Finally, point coordinates and adjacency relationships are checked again for the surface points to be separated. Surface points whose corresponding sources are not found in the reference surface point set are written into the newly exposed surface point set. Through this process, the surface points retained after milling and the newly exposed surface points are separated into two types of point sets, allowing for the separate calculation of the retained surface deformation and the newly exposed range.

[0038] The implementation process includes the following steps: S3-1. Extract reference surface points located outside the cutting front boundary from the reference surface point set, and extract current surface points located outside the cutting front boundary from the current surface point set, recording the point coordinates, adjacent point order, and adjacent edge order. During extraction, first write the cutting front boundary back into the coordinate space of the current surface point set, then read the surface point positions using the cutting front boundary as the dividing line. Surface points located on the side of the cutting front boundary that has not retreated are written into the region outside the cutting front boundary. Subsequently, establish adjacency relationships for each reference surface point and each current surface point within the region outside the cutting front boundary. The adjacency relationships are generated using the triangulation results. Adjacent spatial points within the same set of surface points are connected to form adjacent edges. Then, the surface points directly connected to each surface point are read as adjacent points, with each surface point as the center. The point coordinates are the three-dimensional coordinates of the surface points in the spatial coordinate system. The order of adjacent points is the circumferential arrangement of each adjacent point around the current surface point or the reference surface point. The order of adjacent edges is the arrangement of each adjacent edge in ascending order of length. Taking a section of rock surface that has not been cut at the front end of the excavation as an example, the surface points on this section of rock surface are located outside the boundary of the cutting front at both the reference time and the current time. Therefore, they will enter the extraction range of both the reference surface point and the current surface point and will be used for corresponding point identification in the future.

[0039] S3-2. Calculate the coordinate differences between each reference surface point and all current surface points, and arrange the current surface points in ascending order of coordinate differences. Then, read the current surface points in the arrangement result sequentially to determine the points corresponding to or not corresponding to the reference surface points. Specifically, first calculate the 3D coordinate differences between one reference surface point and all current surface points. The 3D coordinate difference is the modulus of the difference between the 3D coordinates of the current surface point and the 3D coordinates of the reference surface point. This yields a set of coordinate differences. Then, arrange all current surface points in ascending order of coordinate differences to form a sorting result. Next, starting from the first position in the sorting result, read each current surface point sequentially, comparing the order of adjacent points and adjacent edges for each current surface point. If the order of adjacent points is the same as the order of adjacent points corresponding to the reference surface point, and the order of adjacent edges is the same as the order of adjacent edges corresponding to the reference surface point, then the current surface point is sorted. If the current surface point is not found to be a reference surface point, then the current surface point is identified as the corresponding point of the reference surface point, and the search for the current reference surface point is stopped. If the current surface point read does not meet these two conditions, then the search continues to the next current surface point in the sorting. If all current surface points in the sorting result fail to pass these two comparisons, then this reference surface point is recorded as a non-corresponding reference surface point. The reason for adopting this method is that relying solely on the point coordinate distance can easily lead to the miswriting of surface points that are close in location but have different structural origins as corresponding points. By including the order of adjacent points and the order of adjacent edges in the judgment, it is possible to separate current surface points that are close in location and whose local connection relationship remains unchanged. Taking the area with shallow cracks on the rock surface at the front end of the excavation as an example, the surface points on both sides of the crack may be very close in spatial location, but the order of the adjacent points and the order of the adjacent edge lengths of the surface points on both sides are different, so they can still be separated.

[0040] S3-3. Summarize the corresponding points of the reference surface points according to the current surface point to form a set of retained surface points. Specifically, first merge all the reference surface point corresponding points obtained in S3-2 according to the current surface point. When a current surface point corresponds to only one reference surface point, it means that this current surface point retains only one correspondence, and this current surface point is directly determined as a retained surface point. When a current surface point corresponds to two or more reference surface points simultaneously, it means that multiple reference surface points are pointing to the same current surface point at the current moment. In this case, read the point coordinate differences between these reference surface points and this current surface point, and re-sort them according to the point coordinate differences from smallest to largest. Take the current surface point corresponding to the first position in the sorted list as the retained surface point. The correspondences of reference surface points other than the first in the sorting are no longer retained, and these reference surface points are recorded as uncorresponding reference surface points. After all current surface points are processed according to this rule, all the retained surface points are gathered to form a retained surface point set. After this processing, each retained surface point in the retained surface point set retains only one source relationship. When calculating the deformation of the retained surface in the subsequent calculation, there is only one corresponding path between the retained surface point and the reference surface point, and there will be no one-to-many writing. Taking a region with a high density of local surface points as an example, two reference surface points may be close to the same current surface point at the current moment. In this case, the first one is retained by sorting the point coordinate difference, and the remaining source relationships are no longer retained, thereby completing the conflict resolution.

[0041] S3-4. For each current surface point that has not entered the retained surface point set, read its positional and adjacency relationships to form surface points to be classified. Specifically, first, remove current surface points that have entered the retained surface point set from the current surface point set, leaving the remaining current surface points as the surface points to be judged. Then, read two pieces of information for each surface point to be judged: one is whether the surface point to be judged is located outside or behind the cutting front boundary; the other is whether the surface point to be judged has an adjacent edge with a surface point in the retained surface point set. The positional relationship is obtained by comparing the axial coordinate of the surface point to be judged in the unfolded surface with the axial coordinate of the corresponding circumferential position on the cutting front boundary. Surface points whose axial coordinates are located on the backward direction are determined to be located behind the cutting front boundary. The adjacency relationship is... The edges formed by triangulation are directly read. When there is a direct edge between the surface point to be judged and any retained surface point, it is determined that there is an adjacent edge. Only the current surface point that meets both the conditions of "located behind the cutting front boundary" and "has an adjacent edge with a retained surface point" is written into the surface point to be divided. The current surface point located outside the cutting front boundary, and the current surface point that does not have an adjacent edge with a retained surface point, will not be included in the subsequent division. The reason for adopting this processing method is that the newly exposed surface point must appear in the newly exposed area formed by the cutting retreat, and has a boundary connection relationship with the original surface area that is still retained. Therefore, by dividing from both sides of the positional relationship and the adjacency relationship, the newly exposed area on the rear side can be separated from other irrelevant areas.

[0042] S3-5. Calculate the coordinate difference between each surface point to be divided and all reference surface points, and compare the order of adjacent points and adjacent edges to form a new exposed surface point set. Specifically, first calculate the coordinate difference between each surface point to be divided and all reference surface points. Then, arrange all reference surface points in ascending order of coordinate difference. Next, read the reference surface points starting from the first position in the sorting and compare the order of adjacent points and adjacent edges sequentially. If no reference surface point is found that simultaneously satisfies the conditions of "first position in coordinate difference sorting, same adjacent point order, and same adjacent edge order," it indicates that this surface point to be divided has no corresponding source at the reference time, and thus this surface point to be divided is determined as a new exposed surface point. If a reference surface point exists that satisfies the condition of "first position in coordinate difference sorting, same adjacent point order, and same adjacent edge order," then this surface point to be divided has no corresponding source at the reference time, and is therefore determined as a new exposed surface point. If these three conditions are met, it means that the surface point to be divided can still find its source relationship at the reference time, and it will no longer be written into the newly exposed surface point. After all the surface points to be divided are processed, all the newly exposed surface points are collected to form the newly exposed surface point set. Here, the first position of the point coordinate difference sorting and the two types of adjacency relationship are used as the discrimination conditions at the same time. The purpose is to avoid mistakenly writing the current surface point located on the back but still originating from the reference surface point as a newly exposed surface point. Taking a small rock surface newly exposed after milling as an example, this rock surface does not have a corresponding surface point at the reference time. Therefore, after comparing any surface point to be divided with all the reference surface points, it is impossible to find a reference surface point that meets all three conditions at the same time. Finally, the surface points to be divided on this rock surface will enter the newly exposed surface point set.

[0043] In this implementation method, a corresponding point is first established between the reference surface point set and the current surface point set. Then, a retained surface point set is separated from the corresponding point of the reference surface point. Subsequently, a new exposed surface point set is further separated from the current surface points that have not entered the retained surface point set, thereby separating the original surface that is still retained from the surface newly exposed after milling. Here, the surface points with close positions are first picked out using the point coordinate difference, and then the points that truly come from the same surface are separated using the adjacent point order and adjacent edge order. When multiple reference surface points point to the same current surface point, only the corresponding relationship with the closer distance is retained. Then, from the current surface points that have not entered the retained surface point set, points located on the back side of the cut and directly connected to the retained surface points are screened out as the discrimination range for subsequent newly exposed surface points.

[0044] In practical applications: First, surface points located outside the cutting front boundary are extracted from the reference surface point set and the current surface point set, respectively. Point coordinates, adjacent point order, and adjacent edge order are established for each surface point. Then, the point coordinate difference, adjacent point order, and adjacent edge order are compared between each reference surface point and all current surface points to obtain the corresponding points of the reference surface points. These correspondences are then merged according to the current surface points to eliminate the situation where multiple reference surface points point to the same current surface point, forming a retained surface point set. Next, from the current surface points that have not entered the retained surface point set, surface points located behind the cutting front boundary and adjacent to retained surface points are separated. Point coordinate and adjacency relationship discrimination is repeatedly performed on these surface points and all reference surface points. Surface points without source relationships are written into the newly exposed surface point set. After this processing, the retained surface point set is used for subsequent calculation of retained surface deformation, and the newly exposed surface point set is used for subsequent calculation of the newly exposed range and surface removal changes.

[0045] S4. Calculate the backward distance from the reference boundary point set to the current boundary point set point by point along the cutting front boundary and accumulate them to obtain the cutting back amount. Calculate the front and back coordinate differences for the corresponding points in the retained surface point set to obtain the retained surface deformation amount.

[0046] This implementation method is used to calculate the cutting retraction amount and the retained surface deformation amount based on the cutting front boundary and the retained surface point set, respectively. During processing, the current normal line is first established point by point along the cutting front boundary. Then, the intersection points of the reference boundary line segment group and the current normal line are read on each current normal line, thereby obtaining the boundary retraction distance corresponding to each current boundary point. These are accumulated according to the arrangement order on the cutting front boundary to form the cutting retraction amount. Subsequently, adjacent edges are extracted from each retained surface point and the corresponding reference surface point in the retained surface point set. The arrangement order of the edge lengths and the edge angles of the current adjacent edge group and the reference adjacent edge group are compared to identify displacement points and deformation points. Finally, the coordinate differences before and after the displacement points and deformation points are calculated respectively, and then aggregated according to the adjacency relationship of the retained surface points in the retained surface point set to form the retained surface deformation amount. Through this processing, the cutting boundary retraction amount and the displacement and deformation inside the retained surface are written as two separate results, which can then be used to handle subsequent surface removal changes and disturbance deformation changes.

[0047] The implementation process includes the following steps: S4-1. Extract the current boundary points from the current boundary point set sequentially along the cutting front boundary, connect adjacent current boundary points to form a current boundary segment group, and establish the current normal line at each current boundary point. Specifically, first read all current boundary points on the cutting front boundary in ascending order of circumferential coordinates, then connect adjacent current boundary points sequentially to form a current boundary segment group. When the cutting front boundary reaches the circumferential endpoint, connect the last current boundary point to the first current boundary point to keep the current boundary segment group closed. Subsequently, for any current boundary point, read the preceding and following current boundary segments connected to it, calculate the angle between these two current boundary segments, and then take the bisector of the angle as the direction of the current normal line. The current normal line originates from the current boundary point... Starting from the current boundary point, extend along the bisector of the angle towards the side where the reference boundary point set is located. If a current boundary point is connected to only one current boundary line segment, read the direction of this current boundary line segment and establish the current normal line in the direction perpendicular to this current boundary line segment. The reason for adopting this method is that the cutting front boundary itself is formed by connecting the current boundary points corresponding to the negative points in the current unfolded point list. Therefore, the current normal line should start from the current boundary point and point towards the direction where the reference boundary point set is located, so that the subsequent boundary retreat distance can be obtained in the same value direction. Taking the cutting front boundary as a broken line distribution in a local section as an example, calculate the angle between adjacent line segments at each current boundary point in this section, and establish the current normal line along the bisector of the angle to obtain a set of outward-pointing normal lines.

[0048] S4-2. Extract the intersection points of the reference boundary line segment group formed by the reference boundary point set on each current normal line with the current normal line, and form the cutting allowance. In specific processing, first connect two adjacent reference boundary points in the order of the points in the reference boundary point set to form a reference boundary line segment group; then for each current normal line, sequentially read whether there is an intersection point between it and all reference boundary line segments. If there is an intersection point between the current normal line and a certain reference boundary line segment, read the coordinates of the intersection point and determine it as the intersection point; if a current normal line intersects with multiple reference boundary line segments, take the first intersection point encountered along the current normal line starting from the current boundary point as the valid intersection point; if a current normal line does not intersect with any of the reference boundary line segments, read the two reference edges with the closest circumferential positions on both sides of the current normal line. The boundary points are identified, and these two reference boundary points are connected to form a substitute reference line segment. The intersection of the substitute reference line segment and the current normal line is taken as the effective intersection point. After obtaining the effective intersection point, the distance between the effective intersection point and the current boundary point is calculated, and this distance is determined as the boundary retreat distance of the corresponding current boundary point. Then, according to the arrangement order of the current boundary points on the cutting front boundary, all boundary retreat distances are accumulated sequentially to form the cutting retreat amount. After this processing, each current boundary point obtains a boundary retreat distance, and the retreat degree along the entire cutting front boundary is written as the cutting retreat amount by accumulation. Taking a section with uneven local cutting depth as an example, the distances from different current boundary points on the cutting front boundary to the reference boundary line segment group are not the same. After reading and accumulating them point by point, the cutting retreat degree of the entire section can be written out.

[0049] S4-3. Extract adjacent edges for each retained surface point and its corresponding reference surface point in the retained surface point set, forming a current adjacent edge group and a reference adjacent edge group. Divide the retained surface points into displacement points and deformation points. Specifically, first read the correspondence between the retained surface points and reference surface points formed in step S3. For each retained surface point, extract all current surface points directly connected to it, forming a current adjacent edge group. For the corresponding reference surface point, extract all reference surface points directly connected to it, forming a reference adjacent edge group. Then, calculate the edge length of each adjacent edge in the current adjacent edge group and arrange them in ascending order of edge length. Calculate the edge length of each adjacent edge in the reference adjacent edge group in the same way and arrange them in the reference edge length order. Finally, using the retained surface point and the reference surface point as the center, calculate the included angle between each adjacent edge and arrange them in ascending order of included angle, forming the current included angle order. The arrangement order of the current edge length and the included angle is determined by the following criteria: When the current edge length arrangement order is the same as the reference edge length arrangement order, and the current edge included angle arrangement order is also the same as the reference edge included angle arrangement order, this retained surface point is determined as a displacement point; when the edge length arrangement order changes, or the edge included angle arrangement order changes, this retained surface point is determined as a deformation point. The reason for using this classification method is that a displacement point indicates that the local connection structure around the retained surface point has not changed, only the spatial position has changed; a deformation point indicates that the local connection structure around the retained surface point has changed, and at this time it is no longer just a change in the overall position, but also includes a change in the local shape. Taking the case of a rock surface being translated as a whole without local bulging as an example, the order of the adjacent edge lengths and the included angle order around the retained surface point remain unchanged, and such retained surface points will enter the displacement point; if a local rock surface bulges or cracks, the order of the adjacent edge lengths or the included angle order will change, and such retained surface points will enter the deformation point.

[0050] S4-4. Calculate the front-to-back coordinate difference between the retained surface point and the reference surface point for both displacement and deformation points, and aggregate them according to the adjacency relationship of the retained surface points in the retained surface point set to form the retained surface deformation amount. Specifically, for each displacement point, first read its spatial coordinates and the spatial coordinates of the corresponding reference surface point, and calculate the front-to-back coordinate difference between them. The same method is used to calculate the front-to-back coordinate difference for each deformation point. After completing the point-by-point calculation, based on the adjacency relationship in the retained surface point set, retain surface points with directly adjacent edges are grouped into the same surface patch unit. The front-to-back coordinate differences of all displacement and deformation points within the same surface patch unit are aggregated. In one embodiment, the sum of all front-to-back coordinate differences within the same surface patch unit is used to form the surface deformation amount of that surface patch unit. Then, the surface deformation amounts of all surface patch units are aggregated. The summation continues to obtain the deformation of the retained surface. The reason for using this method is that the deformation of the retained surface is not the displacement value of a single point on the retained surface, but the overall change of the retained surface area. Therefore, it is necessary to take values ​​point by point first, and then aggregate them according to the adjacency relationship. Both displacement points and deformation points participate in the calculation of the difference between the coordinates before and after the change in the retained surface in this process. The displacement points reflect the overall displacement component of the retained surface area, and the deformation points reflect the local shape change component of the retained surface area. Together, they constitute the deformation of the retained surface. Taking the case where a section of the surrounding rock surface moves backward as a whole after milling disturbance and is accompanied by local bulging as an example, the overall backward movement will be written by the difference between the coordinates before and after the change in the displacement points, and the local bulging part will be written by the difference between the coordinates before and after the change in the deformation points. Finally, by aggregating the differences within this section of surface unit according to the adjacency relationship, the comprehensive change of this section of the retained surface can be obtained.

[0051] In this implementation, the boundary retreat distance along the cutting front boundary is read point by point and accumulated to form the cutting retreat amount. The front and rear coordinate differences within the retained surface point set are aggregated according to the adjacency relationship to form the retained surface deformation amount. The former reflects the degree of retreat of the cutting boundary, and the latter reflects the displacement and shape change of the uncut part. The current normal line starts from the current boundary point and points to the direction of the reference boundary point set, so the reading path of the boundary retreat distance remains fixed. The displacement points and deformation points are distinguished by the order of the edge length and the order of the edge angle of the adjacent edge group, so the retained surface deformation amount is supported by the local connection relationship between the surface points. After taking the values ​​point by point and aggregating them according to the adjacency relationship, the cutting boundary change and the retained surface change are written as results that can be directly called in subsequent steps.

[0052] In practical applications: First, extract the current boundary points point by point along the cutting front boundary, connect adjacent current boundary points to form a current boundary line segment group, and establish the current normal line at each current boundary point according to the bisector of the included angle between two adjacent current boundary line segments; then connect the reference boundary point set to form a reference boundary line segment group, and extract the intersection point of the reference boundary line segment group and the current normal line on each current normal line, calculate the distance between the intersection point and the current boundary point, obtain the boundary retreat distance point by point, and accumulate it to form the cutting retreat amount; then read the correspondence between the retained surface points and the reference surface points, extract the adjacent edges for each retained surface point and the corresponding reference surface point to form the current adjacent edge group and the reference adjacent edge group, and then divide the retained surface points into displacement points and deformation points according to the order of edge length and the order of edge included angle; finally, calculate the front and rear coordinate differences of the displacement points and deformation points respectively, and collect them according to the adjacency relationship between the retained surface points to form the retained surface deformation amount, and then send the cutting retreat amount and the retained surface deformation amount into the subsequent steps for the calculation of surface removal changes, disturbance deformation changes, and surrounding rock monitoring results.

[0053] S5. Determine the newly exposed area based on the newly exposed surface point set, define the cutting retreat amount and the newly exposed area as surface removal changes, define the retained surface deformation amount as disturbance deformation changes, and output the surrounding rock monitoring results according to the cutting front boundary.

[0054] This implementation method further organizes the newly exposed surface point set, cutting retraction amount, and retained surface deformation amount into surface removal changes, disturbance deformation changes, and surrounding rock monitoring results distributed along the cutting front boundary. During processing, each newly exposed surface point in the newly exposed surface point set is first assigned to its corresponding boundary point in the cutting front boundary, thus obtaining the newly exposed range corresponding to each boundary point. Then, the cutting retraction amount is expanded according to the boundary point position and merged with the corresponding newly exposed range to obtain the surface removal change. Subsequently, the retained surface deformation amount is written to each boundary point according to the adjacency transfer relationship between the retained surface point set and the cutting front boundary, obtaining the disturbance deformation change. Finally, the surface removal change and disturbance deformation change are written as the surrounding rock monitoring results according to the same boundary point position. After this processing, the surface changes caused by cutting and the disturbance deformation changes generated by the surrounding rock entity are both written on the baseline of the cutting front boundary. Subsequent readings only require sequential reading along the boundary points to obtain the monitoring information at the corresponding positions.

[0055] The implementation process includes the following steps: S5-1. Calculate the distances between each newly exposed surface point in the newly exposed surface point set and the cutting edge boundary, forming the newly exposed range corresponding to each boundary point. Specifically, first read all boundary points in the cutting edge boundary, then calculate the spatial distances from each newly exposed surface point to all boundary points. The spatial distance uses the three-dimensional Euclidean distance between the newly exposed surface point and the boundary points. After completing all distance calculations, arrange all boundary points in ascending order of distance, and take the boundary point corresponding to the first point in the sort as the assigned boundary point for this newly exposed surface point. If two or more boundary points have the same distance to the same newly exposed surface point, read the circumferential coordinates of these boundary points, and take the boundary point with the smaller absolute value of the difference between its circumferential coordinate and the projected circumferential position of the newly exposed surface point as the assigned boundary point. After all newly exposed surface points have been assigned, gather them according to their assigned boundary points and group them to the same assigned boundary. The newly exposed surface points of the boundary point are written as a group; then, the axial and circumferential coordinates of this group of newly exposed surface points are read respectively. The difference between the maximum and minimum values ​​of the axial coordinates is taken as the axial span, and the difference between the maximum and minimum values ​​of the circumferential coordinates is taken as the circumferential span. This group of newly exposed surface points, together with the axial span and circumferential span, is written as the newly exposed range corresponding to this boundary point. The reason for adopting this processing method is that the set of newly exposed surface points is itself a point set. When it is necessary to correspond to the boundary points point by point in the future, it is not enough to just keep the point set. Therefore, it is necessary to reorganize the point set according to the boundary point and add the span information. Taking the appearance of a newly exposed rock surface behind a certain local section of the cutting front boundary as an example, the distances of each newly exposed surface point in this rock surface to several boundary points in this section are shorter. After being assigned according to the first and second place of the sort, they will be concentrated on the boundary points of this local section, thus obtaining the newly exposed range of the corresponding section.

[0056] S5-2. According to the arrangement order of each boundary point in the cutting front boundary, write the cutting retraction amount and the retained surface deformation amount to each boundary point respectively, forming the surface removal change and disturbance deformation change; in specific processing, first read the boundary retraction distance obtained point by point in S4-2, and write the boundary retraction distance corresponding to each boundary point as the retraction component corresponding to that boundary point according to the arrangement order of the boundary points in the cutting front boundary; then merge the retraction component corresponding to the same boundary point with the newly exposed range obtained in S5-1 to form the surface removal change corresponding to that boundary point, where the surface removal change includes at least the retraction component, the newly exposed surface point group, the axial span, and the circumferential span; then perform boundary point allocation for the retained surface deformation amount, specifically: first read the adjacency transfer path between each retained surface point in the retained surface point set and the cutting front boundary, the adjacency transfer path adopts the path of the retained surface point tracing back to the cutting front boundary point by point along the adjacent edge; for a retained surface point, along The adjacent edges are read sequentially from the next adjacent point until the path first reaches a certain boundary point in the cutting front boundary. This boundary point is then determined as the assigned boundary point of the retained surface point. The front-to-back coordinate difference corresponding to the retained surface point is then written into the assigned boundary point. After all retained surface points have been assigned, all front-to-back coordinate differences assigned to the same boundary point are summed to form the disturbance deformation change corresponding to that boundary point. The reason for using this method is that the cutting retreat amount itself comes from the boundary point level calculation, while the retained surface deformation amount comes from the surface point level calculation. To put the two into the same output structure, the retained surface point level result must first be written back to the boundary point level. Taking a rock surface that has not been cut but has bulged behind the cutting front boundary as an example, the retained surface points in this rock surface can be traced back to the corresponding boundary points along the adjacent edges. After assignment, the front-to-back coordinate differences of these retained surface points are accumulated to the boundary point to form the disturbance deformation change corresponding to that boundary point.

[0057] S5-3. According to the arrangement order of each boundary point in the cutting front boundary, write the surface removal change and disturbance deformation change into each boundary point to form the surrounding rock monitoring results. In specific processing, first read all the boundary points in the cutting front boundary in ascending order of circumferential coordinates, then read the surface removal change and disturbance deformation change corresponding to each boundary point, and write them together into the result item of that boundary point. The result item should include at least the boundary point coordinates, the yield component, the newly exposed surface point group, the axial span, the circumferential span, and the disturbance deformation change value. After writing all the boundary points in sequence, write them according to the boundary point arrangement order. All results are collected to form the surrounding rock monitoring results. With this writing method, the surrounding rock monitoring results are no longer a scattered set of points or independent quantities, but a set of results that unfold point by point along the cutting front boundary. Therefore, whether reading local sections, comparing adjacent sections, or directly outputting to the construction monitoring interface, they can be read directly in the order of boundary points. Taking the case where a certain section of the cutting front boundary has both obvious retreat and large disturbance deformation as an example, the results of the boundary points of this section will simultaneously write a larger retreat component, a more concentrated new exposure range, and a higher disturbance deformation change value. In this way, the state of the surrounding rock in this section can be directly separated from the entire boundary.

[0058] In this implementation, the newly exposed surface point set is assigned to the corresponding boundary point in the cutting front boundary, the cutting retreat amount is decomposed into retreat components per boundary point, and the retained surface deformation amount is also written to the boundary point along the adjacent transfer path. Finally, the surface removal change and the disturbance deformation change are placed in the same boundary point result item, forming the surrounding rock monitoring result unfolded along the cutting front boundary. After this processing, the surface removal change and the disturbance deformation change are no longer scattered on different objects, but both fall at the boundary point level, and subsequent reading and comparison can be directly performed along the boundary point sequence. At the same time, the correspondence between the newly exposed range, the retreat component and the disturbance deformation change is also fixed under the same boundary point, which facilitates subsequent analysis around a certain local segment.

[0059] In practical applications: First, calculate the spatial distance from each newly exposed surface point in the set of newly exposed surface points to all boundary points in the cutting front boundary. Determine the assigned boundary point according to the first position in the sorting. Group the newly exposed surface points assigned to the same boundary point and read the axial span and circumferential span of the group to form the corresponding newly exposed range. Then, write the boundary retreat distance corresponding to each boundary point obtained in S4-2 as the retreat component and merge it with the newly exposed range corresponding to the boundary point to form the surface removal change. Subsequently, read each retained surface point in the set of retained surface points and trace it point by point along the adjacent edge to the assigned boundary point in the cutting front boundary. Write the corresponding front and back coordinate differences to the assigned boundary point and sum all the front and back coordinate differences received by the same boundary point to form the disturbance deformation change. Finally, write the surface removal change and disturbance deformation change together into each boundary point according to the order of the boundary points in the cutting front boundary to obtain the surrounding rock monitoring results. The surrounding rock monitoring results are then used for subsequent construction monitoring display and surrounding rock condition interpretation.

[0060] A monitoring system for disturbance and deformation of surrounding rock in milling tunnels, as shown in the attached figure. Figure 2 As shown, it includes: The time-series acquisition module is used to perform visual inspection of the rock surface at the excavation front end and the adjacent tunnel wall at the reference time, extract the surrounding rock boundary points and surrounding rock surface points to form the reference boundary point set and the reference surface point set. At the current time, it performs visual inspection of the rock surface at the excavation front end and the adjacent tunnel wall, extracts the surrounding rock boundary points and surrounding rock surface points to form the current boundary point set and the current surface point set.

[0061] The cutting front identification module projects the reference boundary point set and the current boundary point set onto the same unfolding surface, calculates the front-to-back distance point by point along the unfolding direction, determines the adjacent coordinate segments between the zero-point and the negative-point distance as the cutting front zone, and connects the current boundary points corresponding to the negative points to form the cutting front boundary.

[0062] The surface sorting module searches for corresponding points in the current surface point set from the reference surface point set. Surface points located outside the cutting front boundary and whose adjacency remains unchanged are identified as the retained surface point set, while current surface points located behind the cutting front boundary and not included in the retained surface point set are identified as the newly exposed surface point set. The retreat calculation module calculates and accumulates the retreat distance from the reference boundary point set to the current boundary point set along the cutting front boundary to obtain the cutting retreat amount. It also calculates the difference in coordinates before and after for the corresponding points in the retained surface point set to obtain the retained surface deformation amount. The results output module determines the newly exposed area based on the newly exposed surface point set, defines the cutting retreat amount and the newly exposed area as surface removal changes, defines the retained surface deformation amount as disturbance deformation changes, and outputs the surrounding rock monitoring results according to the cutting front boundary.

[0063] Working principle: This scheme performs visual inspections on the rock surface and adjacent tunnel walls at two time points before and after milling. First, the collected results are restored to spatial points, and then the surrounding rock boundary points and surrounding rock surface points are separated from the spatial points. Then, the boundary points from the two time points are written into the same unfolded surface. By using the axial difference, the section that transitions from the non-retreating position to the retreating position is found, thus obtaining the cutting front boundary. On this basis, the current surface points are divided into two parts: one part is the retained surface points whose original source can be traced back at both time points, and the other part is the surface points newly exposed on the side after cutting that have no source at the reference time. Then, the boundary retreat distance is calculated along the cutting front boundary to obtain the cutting retreat amount, and the coordinate difference between the retained surface points and the corresponding reference surface points is calculated to form the retained surface deformation amount. Finally, the newly exposed surface points are assigned to the corresponding boundary points to form the new exposure range, and the cutting retreat amount, the new exposure range, and the retained surface deformation amount are all written to each boundary point of the cutting front boundary, thereby outputting the surface removal change and the disturbance deformation change separately.

[0064] For example, in milling tunnel construction, before the equipment completes a round of cutting, it first performs a visual inspection of the rock surface at the excavation front to obtain a reference image; after the cutting is completed, it performs another visual inspection at the same location to obtain the current image; the system first restores the two images into three-dimensional points, and then finds where the two boundaries retreated, thereby determining the cutting front boundary; then it determines which surface points existed before and are still retained, and which surface points are newly exposed after cutting; in this way, the system can separate "this rock surface has been milled away" from "this rock surface has not been milled away, but has been displaced or bulged" for processing; for example, if a certain boundary has retreated significantly, and a new rock surface appears behind this section, while the coordinates of the adjacent uncut area change, then the system will write the first two parts as surface removal changes and the latter part as disturbance deformation changes. Construction personnel can check the results at each location along the cutting front boundary and directly see which section mainly corresponds to cutting advancement and which section is accompanied by surrounding rock deformation.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for monitoring disturbance and deformation of surrounding rock in milling tunnels, characterized in that, Includes the following steps: S1. At the reference time, visual inspection is performed on the rock surface at the front end of the excavation and the adjacent tunnel wall to extract the surrounding rock boundary points and surrounding rock surface points, forming a reference boundary point set and a reference surface point set. At the current time, visual inspection is performed on the rock surface at the front end of the excavation and the adjacent tunnel wall to extract the surrounding rock boundary points and surrounding rock surface points, forming a current boundary point set and a current surface point set. S2. Project the reference boundary point set and the current boundary point set onto the same unfolding surface, calculate the front and rear distances point by point along the unfolding direction, determine the adjacent coordinate segments between the zero point and the negative value point as the cutting front edge zone, and connect the current boundary points corresponding to the negative value points to form the cutting front edge boundary. S3. Search for corresponding points in the current surface point set for the reference surface point set. Determine the surface points located outside the cutting front boundary and whose adjacency relationship remains unchanged as the retained surface point set. Determine the current surface points located behind the cutting front boundary and not entering the retained surface point set as the newly exposed surface point set. S4. Calculate the back distance from the reference boundary point set to the current boundary point set point by point along the cutting front boundary and accumulate them to obtain the cutting back amount. Calculate the front and back coordinate differences for the corresponding points in the retained surface point set to obtain the retained surface deformation amount. S5. Determine the new exposure range based on the newly exposed surface point set, determine the cutting retreat amount and the newly exposed range as surface removal changes, determine the retained surface deformation amount as disturbance deformation changes, and output the surrounding rock monitoring results according to the cutting front boundary.

2. The method for monitoring disturbance and deformation of surrounding rock in a milling tunnel according to claim 1, characterized in that, Step S1 includes: S1-1. The visual detection results at the reference time and the visual detection results at the current time are spatially restored according to the correspondence between pixel position and spatial position to form a reference spatial point set and a current spatial point set. S1-2. The reference spatial point set and the current spatial point set are divided into multiple angular directions along the circumference, starting from the center point of the rock surface at the front end of the excavation. The spatial points in each angular direction are sorted according to their distance from the center point of the rock surface at the front end of the excavation. The last spatial point in the sorting is taken as the surrounding rock boundary point to form the reference boundary point set and the current boundary point set. S1-3. Extract spatial points located between adjacent surrounding rock boundary points from the reference spatial point set and the current spatial point set, respectively, as surrounding rock surface points to form the reference surface point set and the current surface point set.

3. The method for monitoring disturbance and deformation of surrounding rock in a milling tunnel according to claim 1, characterized in that, Step S2 includes: S2-1. Project the reference boundary point set and the current boundary point set onto the same unfolding surface according to the tunnel axial coordinate and circumferential coordinate respectively, and arrange them according to the circumferential coordinate to form a reference unfolding point column and a current unfolding point column; S2-2. Take corresponding points for the reference unfolded point series and the current unfolded point series according to the same circumferential position, calculate the current axial coordinate of each corresponding point and subtract the reference axial coordinate to obtain the axial difference, and form an axial difference sequence. S2-3. Extract the adjacent coordinate segments between points with an axial difference of zero and points with an axial difference less than zero from the axial difference sequence to form the cutting front edge zone; S2-4. Extract the current unfolded points corresponding to the points with axial differences less than zero in the cutting front zone, and connect them according to the circumferential coordinates to form the cutting front boundary.

4. The method for monitoring disturbance and deformation of surrounding rock in a milling tunnel according to claim 1, characterized in that, Step S3 includes: S3-1. Extract reference surface points located outside the cutting front boundary from the reference surface point set, extract current surface points located outside the cutting front boundary from the current surface point set, and record the point coordinates, adjacent point order, and adjacent edge order for each reference surface point and each current surface point respectively. S3-2. Calculate the point coordinate difference between each reference surface point and all current surface points. Arrange the current surface points in ascending order of point coordinate difference. Read the current surface points in the arrangement result in sequence. Determine the first current surface point with the same adjacent point order and adjacent edge order as the corresponding reference surface point. If none of the current surface points in the arrangement result satisfy the requirements of the same adjacent point order and adjacent edge order, determine the corresponding reference surface point as a non-corresponding reference surface point. S3-3. Summarize the corresponding points of the reference surface points according to the current surface points. When one current surface point corresponds to one reference surface point, the current surface point is determined as a reserved surface point. When one current surface point corresponds to two or more reference surface points, read the point coordinate difference for each corresponding reference surface point, take the current surface point corresponding to the first position of the point coordinate difference sorted by the first position, determine it as a reserved surface point, and determine the remaining reference surface points as uncorresponding reference surface points. Gather all the reserved surface points to form the reserved surface point set. S3-4. Read the positional and adjacency relationships of the current surface points that have not entered the set of retained surface points one by one. When the current surface point is located behind the cutting front boundary and has an adjacent edge with the surface points in the set of retained surface points, the current surface point is determined as a surface point to be divided. When the current surface point is located outside the cutting front boundary or there is no adjacent edge between the current surface point and the surface points in the set of retained surface points, stop the current surface point division. S3-5. Calculate the point coordinate difference between each surface point to be divided and all reference surface points, and compare the order of adjacent points and adjacent edges respectively. If there is no reference surface point among all reference surface points that simultaneously satisfies the following conditions: the point coordinate difference is first in the sorting, the adjacent point order is consistent, and the adjacent edge order is consistent, then the surface point to be divided is determined as the newly exposed surface point. All newly exposed surface points are collected to form the set of newly exposed surface points. If there is a reference surface point among all reference surface points that simultaneously satisfies the following conditions: the point coordinate difference is first in the sorting, the adjacent point order is consistent, and the adjacent edge order is consistent, then stop dividing the surface point to be divided.

5. The method for monitoring disturbance and deformation of surrounding rock in a milling tunnel according to claim 1, characterized in that, Step S4 includes: S4-1. Extract the current boundary points in the current boundary point set sequentially along the cutting front boundary, connect adjacent current boundary points to form a current boundary line segment group, and establish a current normal line at each current boundary point according to the bisector of the included angle between two adjacent current boundary line segments. S4-2. Extract the intersection points of the reference boundary line segment group formed by the reference boundary point set on each current normal line and the current normal line. Determine the distance between the intersection point and the current boundary point as the boundary retreat distance. Add up all the boundary retreat distances according to the arrangement order of the current boundary points on the cutting front boundary to form the cutting relief amount. S4-3. Extract adjacent edges from each retained surface point and the corresponding reference surface point in the retained surface point set to form a current adjacent edge group and a reference adjacent edge group. Calculate the edge length arrangement order and the edge angle arrangement order for the current adjacent edge group and the reference adjacent edge group respectively. When the edge length arrangement order and the edge angle arrangement order are consistent, the retained surface point is determined as a displacement point. When the edge length arrangement order or the edge angle arrangement order is inconsistent, the retained surface point is determined as a deformation point. S4-4. Calculate the front and rear coordinate differences between the retained surface point and the reference surface point for the displacement point and deformation point respectively, and collect all the front and rear coordinate differences according to the adjacency relationship of the retained surface point in the set of retained surface points to form the retained surface deformation amount.

6. The method for monitoring disturbance and deformation of surrounding rock in a milling tunnel according to claim 1, characterized in that, Step S5 includes: S5-1. Calculate the distance between each newly exposed surface point in the newly exposed surface point set and the boundary of the cutting front edge. Take the boundary point corresponding to the first point in the sorting of the distance between the points as the assigned boundary point, and gather the newly exposed surface points according to the assigned boundary points to form the newly exposed range corresponding to each boundary point. S5-2. According to the arrangement order of each boundary point in the cutting front boundary, the cutting retraction amount is allocated to each boundary point, and the cutting retraction amount corresponding to each boundary point is merged with the newly exposed range to form the surface removal change. The remaining surface deformation amount is allocated to each boundary point according to the adjacency relationship between the set of remaining surface points and the cutting front boundary to form the disturbance deformation change. S5-3. According to the arrangement order of each boundary point in the cutting front boundary, write the surface removal change and the disturbance deformation change into each boundary point to form the surrounding rock monitoring result.

7. A monitoring system for disturbance and deformation of surrounding rock in milling tunnels, using the method described in any one of claims 1-6, characterized in that, include: The time-series acquisition module is used to perform visual inspection of the rock surface at the excavation front end and the adjacent tunnel wall at the reference time, extract the surrounding rock boundary points and surrounding rock surface points to form the reference boundary point set and the reference surface point set. At the current time, it performs visual inspection of the rock surface at the excavation front end and the adjacent tunnel wall, extracts the surrounding rock boundary points and surrounding rock surface points to form the current boundary point set and the current surface point set. The cutting front identification module is used to project the reference boundary point set and the current boundary point set onto the same unfolding surface, calculate the front-to-back distance point by point along the unfolding direction, determine the adjacent coordinate segments between the zero-point and the negative-point front-to-back distance as the cutting front edge zone, and connect the current boundary points corresponding to the negative points to form the cutting front edge boundary. The surface sorting module is used to search for corresponding points in the current surface point set for the reference surface point set, determine the surface points located outside the cutting front boundary and whose adjacency relationship remains unchanged as the retained surface point set, and determine the current surface points located behind the cutting front boundary and not entering the retained surface point set as the newly exposed surface point set. The retreat calculation module is used to calculate and accumulate the retreat distance from the reference boundary point set to the current boundary point set along the cutting front boundary point by point to obtain the cutting retreat amount, and to calculate the front and rear coordinate difference for the corresponding points in the retained surface point set to obtain the retained surface deformation amount. The result output module is used to determine the new exposure range based on the newly exposed surface point set, determine the cutting retreat amount and the new exposure range as surface removal changes, determine the retained surface deformation amount as disturbance deformation changes, and output the surrounding rock monitoring results according to the cutting front boundary.

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