Fine survey method and system for integrity degree of foundation pit earthing rock mass

Abstract

The invention belongs to the field of geotechnical engineering, and provides a fine surveying method and system for the integrity degree of a foundation pit earthing rock mass in order to solve the problem that the integrity degree information of the earthing rock mass cannot be provided before foundation pit construction at present. The fine surveying method for the integrity degree of the foundation pit earthing rock mass comprises the steps that according to known geology and existing drilling surveying data of a set area, all structural surface abnormal areas and suspected abnormal parts in the rock mass are recognized; fusing cross-hole elastic wave CT reconnaissance data, and screening out a structural plane abnormal region from all suspected abnormal parts; excluding non-rock mass structural surfaces according to the newly-added borehole images at the abnormal areas of the structural surfaces to obtain a rock mass structural surface set, obtaining the combination degree of corresponding rock mass structures according to the characteristics of the rock mass structural surfaces in the rock mass structural surface set, and determining the integrity degree of the rock mass by combining the types and development degrees of the rock mass structural surfaces. The method can provide soil covering rock mass integrity degree information before foundation pit construction, and the actual applicability of an excavation scheme is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of geotechnical engineering, and particularly relates to a fine survey method and system for the completeness of a foundation pit overburden rock mass. BACKGROUND

[0002] The completeness of a rock mass is an important index for evaluating the grade of surrounding rock of an underground engineering. The grade of surrounding rock and the structural plane of a rock mass determine the structural capacity of the rock mass, which is manifested as a stable vertical height. The structural capacity of the rock mass stable vertical height can reduce or ignore the rock mass support of a soil-rock dual foundation pit, thereby saving the cost. The structural capacity of the soil-rock dual foundation pit rock mass has an important influence on the design scheme. However, the rock mass is covered by soil, and the structural plane and the completeness of the rock mass must be mastered before the construction of the foundation pit, so as to ensure the pertinence and applicability of the excavation scheme. The completeness of the rock mass and the properties of the structural plane in the prior art are generally obtained by geological mapping methods, which are mainly applicable to exposed rock masses or rock masses that can be exposed after excavation, and are not applicable to overburden rock masses.

[0003] In summary, there is currently a lack of a completeness survey method for overburden rock masses, which cannot provide information on the structural capacity of overburden rock masses for soil-rock dual foundation pit design, thereby resulting in a lack of pertinence and practicality of the design scheme, causing great waste or safety hazards. SUMMARY

[0004] To solve the above technical problems, the present application provides a fine survey method and system for the completeness of a foundation pit overburden rock mass, which is applicable to rock foundation pit engineering mainly composed of rock masses and intended to use a little support or no support scheme, can provide information on the completeness of overburden rock masses before the construction of the foundation pit, and ensure the practical applicability of the excavation scheme.

[0005] To achieve the above purpose, the present application adopts the following technical solutions: The first aspect of the present application provides a fine survey method for the completeness of a foundation pit overburden rock mass.

[0006] In one or more embodiments, a fine survey method for the completeness of a foundation pit overburden rock mass is provided, comprising: According to the known geology of the set area and the existing drilling survey data, all structural plane abnormal areas and suspected abnormal parts in the rock mass are identified; Fusion cross-hole elastic wave CT re-survey data, re-select structural plane abnormal areas from all suspected abnormal parts; According to the new drilling image at each structural plane abnormal area, non-rock mass structural planes are excluded to obtain a rock mass structural plane set, wherein the depth of the new drilling is greater than the maximum depth of all structural plane abnormal areas; According to the characteristics of each rock mass structure surface in the rock mass structure surface set, the combination degree of the corresponding rock mass structure is obtained, and then the integrity degree of the rock mass is determined according to the type and development degree of the rock mass structure surface.

[0007] As an implementation, the geophysical survey line and the drilling position are determined according to the known geology of the set region, and all suspected abnormal positions in the rock mass are identified by combining the drilling survey data of the high-density electrical method and the transient electromagnetic method.

[0008] As an implementation, all suspected abnormal positions in the rock mass are identified by using a first joint decision function; the first joint decision function is , and the expression is ; ; ; ; ; wherein, represents the relative anomaly of the high-density electrical method; represents the relative anomaly rate of the transient electromagnetic method; and are weight coefficients, and the sum of the two is 1; is the sliding background resistivity; is the resistivity of the high-density electrical method; is the resistivity of the transient electromagnetic method; is the background value; is the measurement point coordinate; and are both constants; when is greater than or equal to a first threshold value, it is determined that the position has a structure surface abnormal region; when is less than the first threshold value and greater than or equal to a second threshold value, it is determined that the position is a suspected abnormal position; wherein the second threshold value is less than the first threshold value; and are normalization functions.

[0009] As an implementation, based on the drilling survey data of the high-density electrical method and the transient electromagnetic method, the cross-hole elastic wave CT re-survey data is further fused, and a second joint decision function is combined to re-screen the structure surface abnormal region from all suspected abnormal positions.

[0010] As an implementation, the second joint decision function is , and the expression is ; ; ;

[0011] ; ; ; wherein, represents the relative anomaly of high-density electrical method; represents the relative anomaly rate of transient electromagnetic method; represents the relative anomaly rate of elastic wave CT; represents the wave velocity obtained by inversion at the location x ; represents the background wave velocity value reflected by the area with no abnormal wave velocity change in the same depth interval as the point x ; 、 、 is a weight coefficient, and the sum of the three is 1; is the sliding background resistivity; is the resistivity of high-density electrical method; is the resistivity of transient electromagnetic method; is the background value; is the measurement point coordinate; 、 、 are all constants; when is greater than or equal to a set threshold, it is determined that the location is an abnormal area of structural plane; 、 and are normalization functions.

[0012] As an implementation mode, the development degree is represented by the number of structural plane sets and the average spacing.

[0013] As an implementation mode, the determination process of the number of structural plane sets is as follows: According to the image of the newly added borehole, the corresponding rock mass structural plane is fitted to obtain the corresponding occurrence parameters, which are converted into direction vectors on the corresponding unit sphere; The direction vector representation is clustered, the minimum spherical angle distance is used as the similarity index, and the direction aggregation cluster is identified to realize the grouping determination of the rock mass structural plane.

[0014] As an implementation mode, the calculation process of the average spacing is as follows: The center point coordinates of each fitted plane in each group are extracted to form a center point coordinate set; Calculate the unit normal vector of each rock mass structural plane, find its average direction, define as group normal vector and unitize; Project each center point in the set of center point coordinates in the direction of the unitized group normal vector to obtain a sequence of normal distances to represent the spatial position of the rock mass structural plane in the direction of the group normal vector; Sort all the projection values from small to large, and calculate the average spacing of each group of rock mass structural planes according to the adjacent normal distances; According to the average spacing of each group of rock mass structural planes and the number of structural plane groups, the equivalent average spacing of all rock mass structural planes is obtained by using the weighted average method.

[0015] In one or more embodiments, a fine survey system for the integrity of a foundation covering soil rock mass includes: An anomaly preliminary screening module for identifying all structural plane anomaly regions and suspected anomaly sites in the rock mass according to known geology and existing drilling survey data of a set region; An anomaly re-screening module for fusing cross-hole elastic wave CT re-survey data to re-screen structural plane anomaly regions from all suspected anomaly sites; A structural plane determination module for excluding non-rock mass structural planes according to the image of the new drill hole at each structural plane anomaly region to obtain a set of rock mass structural planes, wherein the depth of the new drill hole is greater than the maximum depth of all structural plane anomaly regions; An integrity determination module for determining the integrity of the rock mass according to the characteristics of each rock mass structural plane in the set of rock mass structural planes, and combining the type and development degree of the rock mass structural plane.

[0016] The third aspect of the present application provides a fine survey device for the integrity of a foundation covering soil rock mass.

[0017] A fine survey device for the integrity of a foundation covering soil rock mass includes a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to implement the steps of the fine survey method for the integrity of a foundation covering soil rock mass as described above.

[0018] Compared with the prior art, the beneficial effects of the present application are: This invention identifies all abnormal areas and suspected abnormal locations of structural planes in rock masses based on existing borehole exploration data. It then integrates cross-hole elastic wave CT re-exploration data to further filter out abnormal areas of structural planes from all suspected abnormal locations. Finally, it combines newly added borehole images to exclude non-rock mass structural planes. Based on the characteristics of each rock mass structural plane in the set of rock mass structural planes, the degree of integration of the corresponding rock mass structure is obtained. Combined with the type and development degree of the rock mass structural planes, the integrity of the rock mass is determined. This invention solves the problem that traditional methods cannot identify deep structural planes under overburden conditions and lack a basis for rock mass integrity evaluation. It significantly improves the accuracy and systematicness of structural plane identification under complex geological conditions, resulting in multiple engineering benefits such as improved parameter determination accuracy, reduced engineering uncertainty, and enhanced reliability of foundation pit design. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] Figure 1 This is a flowchart illustrating the detailed survey method for assessing the integrity of the overburden rock mass in an foundation pit, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of a fine survey system for assessing the integrity of the overburden rock mass in an excavation pit, according to an embodiment of the present invention. Figure 3 This is a schematic diagram of a fine surveying device for assessing the integrity of the overburden rock mass in a foundation pit, according to an embodiment of the present invention. Figure 4 It is a detailed plan view of the survey to determine the integrity of the overburden rock mass of the foundation pit; Figure 5 yes Figure 4 Enlarged view of a portion of the image; Figure 6 It is a schematic diagram of a detailed survey profile for assessing the integrity of the overburden rock mass in the foundation pit; Figure 7 yes Figure 6 Enlarged schematic diagram of a section of the borehole; Figure 8 This is a schematic diagram of the cross-section for structural surface identification from a borehole camera.

[0021] Wherein, 1 - soil-rock interface, 2 - first structural plane, 3 - geological body, 31 - unexcavated soil body, 32 - unexcavated rock body, 33 - excavated soil and rock body, 4 - second structural plane, 5 - third structural plane, 6 - first borehole, 7 - second borehole, 8 - first cross-hole elastic wave CT transmitter / receiver, 9 - second cross-hole elastic wave CT transmitter / receiver, 10 - transverse geophysical survey line, 11 - longitudinal geophysical survey line, 12 - oblique geophysical survey line, 13 - structural plane anomaly area, 14 - third borehole, 15 - camera, 16 - auxiliary light source, 17 - cable assembly, 201 - anomaly preliminary screening module, 202 - anomaly rescreening module, 203 - structural plane determination module, 204 - completeness determination module, 301 - processor, 302 - memory, 303 - user interface, 304 - network interface, 305 - bus system. DETAILED DESCRIPTION

[0022] The application will be further described below with reference to the drawings and examples.

[0023] It should be noted that the following detailed description is illustrative only and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0024] It should be noted that the terms used herein are merely for the purpose of describing specific embodiments and are not intended to limit exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should be further understood that the terms "comprise" and / or "include" as used herein indicate the presence of the features, steps, operations, devices, components and / or combinations thereof.

[0025] Figure 1 is a flowchart of a fine survey method for the completeness of the foundation pit overburden rock mass in an embodiment of the application. Figure 1 The fine survey method for the completeness of the foundation pit overburden rock mass in the present embodiment can include the following steps S101-S104.

[0026] The specific implementation process of steps S101-S104 is as follows: Step S101: According to the known geology of the set area and the existing borehole survey data, identify all structural plane anomaly areas and suspected abnormal parts in the rock mass.

[0027] Figure 4The display is arranged along the edge of the foundation pit excavation part of the geophysical transverse geophysical survey line 10, longitudinal geophysical survey line 11 and oblique geophysical survey line 12, and the first drill hole 6 and the second drill hole 7 need to be set at the intersection of the survey line and the intersection of the transverse and longitudinal survey lines. The survey line is the high-density electrical method and transient electromagnetic method survey line. The cross-hole elastic wave CT test is carried out in the set drill hole according to the principle of adjacent hole test. After the three geophysical tests are completed, the structure surface abnormal area 13 displayed by the survey line will be obtained. The third drill hole 14 with a range of “3x3” is added near the structure surface abnormal area 13. The drill hole camera test will be carried out in the third drill hole 14 added for the structure surface abnormal area 13 in the future, and the structure surface characteristics such as structure surface opening degree, roughness and filling condition are obtained. Figure 5 (a) in FIG. 1 is a local area diagram of the second drill hole 7; Figure 5 (b) in FIG. 1 is a local area diagram of the first drill hole 6, the structure surface abnormal area 13 and the third drill hole 14.

[0028] In the specific implementation process, the geophysical survey line and the drill hole position are determined according to the known geology of the set area, and the drill hole survey data such as high-density electrical data and transient electromagnetic data are combined to identify all suspected abnormal parts in the rock mass.

[0029] A first joint decision function is used to identify all suspected abnormal parts in the rock mass; the first joint decision function is , and the expression is: ; ; ; ; ; , wherein represents the relative anomaly of high-density electrical method; represents the relative anomaly rate of transient electromagnetic method; and are weight coefficients, and the sum of the two is 1; is the sliding background resistivity; is the resistivity of high-density electrical method; is the resistivity of transient electromagnetic method; is the background value; is the measurement point coordinate; and are both constants (for example, is set to 40 Ω·m, is set to 40%); is greater than or equal to the first threshold value (for example, 0.7), it is determined that there is a structure surface abnormal area at the position; when When the value is less than the first threshold (for example, 0.7) and greater than or equal to the second threshold (for example, 0.5), the position is determined as a suspected abnormal part; wherein the second threshold is less than the first threshold; and is a normalization function.

[0030] It should be noted here that, and The value can be dynamically set according to engineering requirements; and The value can also be set according to the actual situation; the setting of the first threshold and the second threshold can be set according to the actual situation by those skilled in the art, which will not be described here in detail.

[0031] The background resistivity here is defined as the typical electrical response value in the neighborhood of the target measurement point. For the high-density electrical method background value , the median value or the filtered average value is calculated by using a sliding window of L = 5-10 meters to the left and right of the target point; for the transient electromagnetic method background value , the median or average value in the range of L = 10-20 meters to the left and right of the measurement point at the same depth (or the same time window) is taken as the reference.

[0032] Step S102: Fuse the cross-hole elastic wave CT re-investigation data, and re-select the structural surface abnormal area from all suspected abnormal parts.

[0033] Specifically, based on the high-density electrical method data and the transient electromagnetic method data, the cross-hole elastic wave CT re-investigation data is fused, and the second joint determination function is combined to re-select the structural surface abnormal area from all suspected abnormal parts. For example, for the case of 0.5 D ( x )≤0.7, in order to improve the accuracy of structural surface identification, the wave velocity information inverted by the elastic wave CT technology is introduced, a three-source joint determination function is constructed, and the above abnormal parts are verified. Based on the relative anomaly amount obtained from the three geophysical results (high-density electrical method, transient electromagnetic method, and elastic wave CT).

[0034] Let the second joint determination function be , and its expression is: ; ; ;

[0035] ; ; ; wherein, represents the relative anomaly of high-density electrical method; represents the relative anomaly rate of transient electromagnetic method; represents the relative anomaly rate of elastic wave CT; represents the wave velocity obtained by inversion at the location x based on the cross-hole elastic wave CT technology; represents the background wave velocity value reflected by the area with no abnormal wave velocity change in the same depth interval as the point x ; , are weight coefficients, and the sum of the three is 1; is the sliding background resistivity; is the resistivity of high-density electrical method; is the resistivity of transient electromagnetic method; is the background value; is the measurement point coordinate; , are all constants (for example, is set to 40 Ω·m, is set to 40%, and is set to 0.3); when is greater than or equal to a set threshold (such as 0.8, which can be specifically set according to actual conditions), it is determined that the location is an abnormal area of structural plane; and are normalization functions.

[0036] It should be noted that, , the values of which can be dynamically set according to engineering requirements; , the values of which can also be specifically set according to actual conditions. The median value or the mean value after removing abnormal points can be obtained.

[0037] Step S103: According to the image of the newly added borehole at each structural plane abnormal area, non-rock mass structural planes are excluded to obtain a rock mass structural plane set, wherein the depth of the newly added borehole is greater than the maximum depth of all structural plane abnormal areas.

[0038] The process of excluding non-rock mass structural planes to obtain a rock mass structural plane set according to the image of the newly added borehole at each structural plane abnormal area is as follows: ​​​​​For the structural plane abnormal response area, drill holes are added to the structural plane abnormal area, the depth of the added drill holes is determined according to the depth of the preliminary determined structural plane abnormal area, and the depth must meet the requirements of covering the structural plane abnormal area and continuing to deepen by ≥2m; if necessary, the survey range of 3*3 range (taking the center of the structural plane abnormal area as the base point, and finding the optimal proportion in the adjacent drill hole longitudinal and lateral spacing of 2-5m according to the size of the abnormal part) can be further reduced to determine the position of the structural plane abnormal area. The drill hole camera technology is selected to determine whether the structural plane abnormal area is a rock mass structural plane.

[0039] Figure 6 is aimed at Figure 4 The profile drawn by the lowermost survey line shows the unexcavated soil body 31, the unexcavated rock mass 32, the excavated soil and rock mass 33 and the soil-rock boundary 1 contained in the geological body 3, the first structural plane 2, the second structural plane 4 and the third structural plane 5 represent the structural planes with different opening degrees in the underlying rock mass. The first drill hole 6, the second drill hole 7 and the third drill hole 14 correspond to Figure 4 The drill holes set by geophysical survey lines or added for the structural plane abnormal area 13 in the figure.

[0040] Figure 7 is a partial enlarged view of Figure 6 gives the process of the cross-hole elastic wave CT test, Figure 7 In the figure, the first drill hole 6 and the second drill hole 7 are taken as examples, and the adjacent hole test is carried out by setting the first cross-hole elastic wave CT transmitter / receiver 8 and the second cross-hole elastic wave CT transmitter / receiver 9 in the holes. The transmitter / receiver is arranged in sections with a spacing of 0.5-1.0m along the hole depth direction; during operation, the transmitting end excites elastic waves in turn, and the receiving end records the propagation time of the waves synchronously, and finally the wave velocity distribution is obtained by time inversion of multiple hole groups, realizing the imaging identification of structural plane and other abnormal bodies.

[0041] Figure 8 is a profile schematic diagram of drill hole camera structural plane identification. In actual operation, the second structural plane 4 is taken as an example, the camera 15 and the auxiliary light source 16 are lowered into the third drill hole 14 added for the structural plane abnormal area 13 through the cable assembly 17, and the structural plane image is recorded by slowly moving along the hole wall; through image magnification and comparative analysis, the opening degree, roughness and filling condition can be identified, and the structural plane state can be directly interpreted.

[0042] Step S104: According to the characteristics of each rock mass structural plane in the rock mass structural plane set, the combination degree of the corresponding rock mass structure is obtained, and the integrity degree of the rock mass is determined in combination with the type and development degree of the rock mass structural plane.

[0043] In the embodiments of the present application, the characteristics of the rock mass structural plane include but are not limited to opening degree and roughness, filling condition. According to the characteristics of each rock mass structural plane in the set of rock mass structural planes, the combination degree of the corresponding rock mass structure is obtained, as shown in Table 1.

[0044] Table 1 Relationship between combination degree and structural plane characteristics

[0045] According to Table 1, the combination degree of the rock mass structure is divided into good, general, poor and very poor; When the structural plane characteristics are opening degree less than 1mm, siliceous, ferruginous or calcareous cementation, or structural plane roughness, no filler; when the structural plane characteristics are opening degree of 1mm-3mm, siliceous or ferruginous cementation; when the structural plane characteristics are opening degree greater than 3mm, structural plane roughness, siliceous cementation; in these cases, the combination degree of the rock mass structure is good.

[0046] When the structural plane characteristics are opening degree less than 1mm, structural plane flat, calcareous cementation or no filler; when the structural plane characteristics are opening degree of 1mm-3mm, calcareous cementation; when the structural plane characteristics are opening degree greater than 3mm, structural plane roughness, ferruginous or calcareous cementation; in these cases, the combination degree of the rock mass structure is general.

[0047] When the structural plane characteristics are opening degree of 1mm-3mm, structural plane flat, argillaceous cementation or calcareous cementation; when the structural plane characteristics are opening degree greater than 3mm, more than half of the argillaceous or detritus filling; in these cases, the combination degree of the rock mass structure is poor.

[0048] When the argillaceous filling or mud and rock detritus filling, the thickness of the filler is greater than the relief difference, the combination degree of the rock mass structure is very poor.

[0049] According to the combination degree of the rock mass structure, combined with the type and development degree of the rock mass structural plane, the completeness of the rock mass is determined, as shown in Table 2, the completeness of the rock mass includes complete, relatively complete, relatively broken, broken and extremely broken.

[0050] Table 2 Completeness of rock mass and corresponding characteristics

[0051] When the number of surface groups of the structural plane is 1-2 groups, the average spacing is greater than 1.0m, the combination degree of the structural plane is good or general, and the type of the structural plane is joint, fissure or layer, the rock mass is judged to be complete. When the number of surface groups of the structural plane is 1-2 groups, the average spacing is greater than 1.0m, the combination degree of the structural plane is poor, and the type of the structural plane is joint, fissure or layer, the rock mass is judged to be relatively complete. When the number of surface groups of the structural surface is 2-3, the average interval is between 1.0 m and 0.4 m, the combination degree of the structural surface is good or general, and the type of the structural surface is joint, fracture or layer, it is judged that the rock mass is relatively complete; When the number of surface groups of the structural surface is 2-3, the average interval is between 1.0 m and 0.4 m, the combination degree of the structural surface is poor, and the type of the structural surface is joint, fracture, layer or small fault, it is judged that the rock mass is relatively broken; When the number of surface groups of the structural surface is greater than or equal to 3, the average interval is between 0.4 m and 0.2 m, the combination degree of the structural surface is good, and the type of the structural surface is joint, fracture, layer or small fault, it is judged that the rock mass is relatively broken; When the number of surface groups of the structural surface is greater than or equal to 3, the average interval is between 0.4 m and 0.2 m, the combination degree of the structural surface is general, and the type of the structural surface is joint, fracture, layer or small fault, it is judged that the rock mass is relatively broken; When the number of surface groups of the structural surface is greater than or equal to 3, the average interval is between 0.4 m and 0.2 m, the combination degree of the structural surface is poor, and the type of the structural surface is joint, fracture, layer or small fault, it is judged that the rock mass is relatively broken; When the number of surface groups of the structural surface is greater than or equal to 3, the average interval is less than 0.2 m, the combination degree of the structural surface is general or poor, and the type of the structural surface is joint, fracture, layer or small fault, it is judged that the rock mass is broken; When the number of surface groups of the structural surface is disordered, the average interval is disordered, and the combination degree of the structural surface is very poor, it is judged that the rock mass is extremely broken.

[0052] When the rock mass structure surface is judged, the point position and occurrence parameters of the structural surface are identified by borehole camera technology: For the point of the rock mass structure surface in the i-th borehole, it is recorded as , wherein is the inclination of the rock mass structure surface point (unit °); is the dip angle of the rock mass structure surface point (unit °); is the point of the rock mass structure surface in the i-th borehole The coordinates of the point in the three-dimensional space are , and the obtaining method is as follows: the oblique strip characteristics of the rock mass structure surface on the borehole wall are identified through the borehole camera development image, and the starting depth and the ending depth are recorded. The central depth of the rock mass structure surface in the i-th borehole is taken as the depth of the point: ; the depth value is combined with the borehole wellhead space coordinates and the borehole trajectory direction to convert the three-dimensional space coordinates of the rock mass structure surface point: If the i-th borehole is the first borehole, the point is recorded as ; if the i-th borehole is not the first borehole, the point is recorded as . If the i-th borehole is the first borehole, the point is recorded as If the first borehole is a vertical well (vertical downward), the crossing point is: ; If the first borehole is a vertical well (vertical downward), the crossing point is: If the first borehole is a vertical well (vertical downward), the crossing point is: and azimuth angle , the spatial position of the borehole can be calculated: .

[0053] According to the following formula to determine the structure surface belonging: , , and ; In the formula, is the dip tolerance ; is the dip tolerance ; is the maximum spatial distance (m), which needs to be determined according to the horizontal and vertical spacing between adjacent boreholes in the added borehole. The rock mass structure surface points that meet the above conditions are clustered into the same rock mass structure surface point set, denoted as .

[0054] In the specific implementation process, the process of fitting and calculating the normal vector of the rock mass structure surface is: The least squares method is used to fit the rock mass structure surface point set to obtain the target fitting plane equation z = Ax + By + C; wherein the rock mass structure surface point set is composed of the coordinates of the rock mass structure surface crossing points in three-dimensional space and the spatial occurrence parameters; The coefficients A, B and C of the target fitting plane are solved by linear regression to minimize the sum of squares of all fitting residuals; such as: ; wherein k is the kth rock mass structure surface; n is the total number of rock mass structure surfaces.

[0055] In order to unify the spatial direction measure standard and facilitate the calculation of the included angle with the excavation side wall direction, the normal vector n 法向量 = (-A,-B,1) of the fitted structure surface needs to be unitized to obtain the unit normal vector , and the calculation formula is: .

[0056] In this embodiment, the occurrence parameters of the fitted structure surface are also calculated, including: dip angle , and dip direction α = arctan2(B,A).

[0057] Wherein, the occurrence parameter data set is: S ={( α 1,β1),( α 2, β 2),…,(α k , β k}, wherein, α k is the dip of the kth structural plane; β k is the dip angle of the kth structural plane.

[0058] In the embodiments of the present application, the development degree is represented by the number of structural plane groups and the average spacing.

[0059] Specifically, the determination process of the number of structural plane groups is as follows: Step a1: according to the newly added borehole image, the corresponding rock mass structural plane is fitted to obtain the corresponding occurrence parameters (including dip α i and dip angle β i ), and converted into a direction vector representation on the corresponding unit sphere: x i = (cos α i ·sin β i ,sin α i ·sin β i ,cos β i ) ; Step a2: the direction vector representation is clustered, the minimum spherical angular distance is used as the similarity index, and the direction aggregation cluster is identified to realize the grouping determination of the rock mass structural plane.

[0060] The direction vector set { x i} is taken as the input of the spherical clustering algorithm, the minimum spherical angular distance is used as the similarity index, the direction aggregation cluster is automatically identified, thereby realizing the grouping determination of the structural plane, and finally the clustering output is carried out, including the number of structural plane groups G, the average dip and dip angle of each group of structural planes and the number of structural planes contained in each group n j , j = 1, 2, …, G.

[0061] In the specific implementation process, the calculation process of the average spacing is as follows: Step b1: the center point coordinates of each fitted plane in each group are extracted to form a center point coordinate set.

[0062] For the jth group of structural planes, the center point coordinates of each fitted plane thereof are extracted to form a set P j = { Pj1 , P j2 ,…, P jn}, the center point coordinate of the mth structural surface in the jth group is P jm =( x jm , y jm , z jm )。

[0063] Step b2: Calculate the unit normal vector of each rock mass structural surface, find its average direction, define it as the group normal vector and unitize it.

[0064] Extract and calculate the unit normal vector of each rock mass structural surface (fitting plane unit normal), find its average direction, define it as the group normal vector: ; and unitize it: .

[0065] Step b3: Project each center point in the center point coordinate set in the direction of the unitized group normal vector to obtain a normal distance sequence to represent the spatial position of the rock mass structural surface in the direction of the group normal vector.

[0066] Project all structural surface center points in the average normal vector direction to obtain the normal distance sequence , which represents the spatial position of the structural surface in the normal direction.

[0067] Step b4: Sort all projection values from small to large, and calculate the average spacing of each group of rock mass structural surfaces according to the adjacent normal distance.

[0068] Sort all projection values from small to large to obtain: , the adjacent normal distance is ; the average spacing of each group of structural surfaces is .

[0069] Step b5: According to the average spacing of each group of rock mass structural surfaces and the number of structural surface groups, the equivalent average spacing of all rock mass structural surfaces is obtained by using the weighted average method.

[0070] The equivalent average spacing of all structural surfaces is obtained by using the weighted average method: .

[0071] The embodiment of the present application adopts the technical scheme of "multi-source geophysical identification-drilling camera verification-rock mass integrity division", and the specific process is that the resistivity anomaly characteristics of the structural plane control zone are jointly extracted in the soil-covered area by high-density electrical method, transient electromagnetic method and cross-hole elastic wave CT technology to preliminarily delineate the structural plane concentrated development area; then the drilling camera technology is used to extract the key parameters such as structural plane opening degree, spacing and surface state to determine the combination degree and spatial distribution characteristics; finally, the rock mass integrity degree is qualitatively and quantitatively divided based on the engineering rock mass classification standard. The scheme solves the problems that the traditional means cannot identify the deep structural plane under the soil condition and the rock mass integrity evaluation lacks basis, significantly improves the accuracy of structural plane identification and the systematicness of evaluation under the complex geological condition, and produces many engineering benefits such as improving the parameter determination accuracy, reducing the engineering uncertainty and enhancing the reliability of foundation pit design.

[0072] As shown in Figure 2 The fine survey system for the rock mass integrity degree of the foundation pit soil provided by the embodiment of the present application can be realized in a software manner, and the fine survey system for the rock mass integrity degree of the foundation pit soil includes the following software modules: an anomaly preliminary screening module 201, an anomaly rescreening module 202, a structural plane determination module 203 and an integrity degree determination module 204.

[0073] The functions of each software module in the fine survey system for the rock mass integrity degree of the foundation pit soil are introduced as follows: The anomaly preliminary screening module 201 is used to identify all structural plane anomaly regions and suspected anomaly parts in the rock mass according to the known geology of the set region and the existing drilling survey data; The anomaly rescreening module 202 is used to fuse the cross-hole elastic wave CT resurvey data to rescreen the structural plane anomaly regions from all suspected anomaly parts; The structural plane determination module 203 is used to exclude non-rock mass structural planes according to the new drilling images at each structural plane anomaly region to obtain a rock mass structural plane set, wherein the depth of the new drilling is greater than the maximum depth of all structural plane anomaly regions; The integrity degree determination module 204 is used to obtain the combination degree of the corresponding rock mass structure according to the characteristics of each rock mass structure in the rock mass structural plane set, and determine the integrity degree of the rock mass in combination with the type and development degree of the rock mass structure.

[0074] It should be noted that each module in the fine survey system for the rock mass integrity degree of the foundation pit soil corresponds to each step in the above fine survey method for the rock mass integrity degree of the foundation pit soil, and the specific implementation process is the same, which will not be described here.

[0075] The structure of the fine survey equipment for the intact degree of the foundation pit covering rock mass of the embodiment of the present application is described in detail below. Figure 3 The component structure diagram of the fine survey equipment for the intact degree of the foundation pit covering rock mass of the embodiment of the present application is provided, and it can be understood that Figure 3 Only the exemplary structure of the fine survey equipment for the intact degree of the foundation pit covering rock mass is shown, not all the structures, and the shown part or all of the structures can be implemented according to the needs.

[0076] The fine survey equipment for the intact degree of the foundation pit covering rock mass provided by the embodiment of the present application comprises at least one processor 301, a memory 302, a user interface 303 and at least one network interface 304. The various components in the fine survey system for the intact degree of the foundation pit covering rock mass are coupled together through a bus system 305. It can be understood that the bus system 305 is used to realize the connection communication between the components. The bus system 305 includes not only a data bus, but also a power supply bus, a control bus and a status signal bus. However, for the purpose of clear illustration, all the buses are marked as the bus system 305 in Figure 3 .

[0077] The user interface 303 can include a display, a keyboard, a mouse, a trackball, a click wheel, a key, a button, a touchpad or a touch screen, etc.

[0078] It can be understood that the memory 302 can be a volatile memory or a non-volatile memory, and can also include both volatile and non-volatile memories. The memory 302 in the embodiment of the present application can store data to support the operation of the terminal. Examples of the data include any computer programs for operating on the terminal, such as an operating system and an application program. The operating system contains various system programs, such as a framework layer, a core library layer, a driver layer, etc., for realizing various basic services and processing hardware-based tasks. The application program can contain various application programs.

[0079] In some embodiments, the fine survey system for the integrity of the foundation covering rock mass provided by the embodiments of the present application can be implemented in a combination of software and hardware. For example, the fine survey system for the integrity of the foundation covering rock mass provided by the embodiments of the present application can be a hardware decoding processor programmed to execute the fine survey method for the integrity of the foundation covering rock mass provided by the embodiments of the present application. For example, the hardware decoding processor can be one or more application specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs), or other electronic components.

[0080] For example, the processor 301 can be an integrated circuit chip with a processing capability of signals, such as a general-purpose processor, a digital signal processor (DSP), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc., where the general-purpose processor can be a microprocessor or any conventional processor.

[0081] As an example of the fine survey system for the integrity of the foundation covering rock mass provided by the embodiments of the present application implemented in hardware, the apparatus provided by the embodiments of the present application can be directly implemented by a hardware decoding processor, such as one or more application specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs), or other electronic components, to execute the fine survey method for the integrity of the foundation covering rock mass provided by the embodiments of the present application.

[0082] The memory 302 in the embodiments of the present application is used to store various types of data to support the operation of the fine survey system for the integrity of the foundation covering rock mass, or to store instructions for executing the fine survey method for the integrity of the foundation covering rock mass provided by the embodiments of the present application. Figure 1program code of the method. Examples of such data include any executable code such as an executable instruction, implementing the method for fine surveying the integrity of the rock mass of the foundation pit covering soil according to the embodiments of the present application, which can be contained in the executable instruction.

[0083] In particular, according to the embodiments of the present application, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, the embodiments of the present application include a computer program product comprising a computer program which is carried on a computer readable medium, the computer program containing instructions for executing the method for fine surveying the integrity of the rock mass of the foundation pit covering soil as defined in the apparatus of the present application. Figure 1 program code of the method. In such embodiments, the computer program can be downloaded and installed from a network through the communication section, and / or installed from a detachable medium. When the computer program is executed by the central processing unit, various functions defined in the apparatus of the present application are executed.

[0084] The present application is described with reference to the flowcharts and / or block diagrams of the methods, apparatus (system) and computer program products of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 one flow or multiple flows and / or blocks Figure 1 the functions specified in one block or multiple blocks.

[0085] The above merely describes the preferred embodiments of the present application and is not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for fine surveying the integrity of a foundation pit covering rock mass, characterized in that, The method comprises the following steps: According to the known geology and existing drilling survey data of the set region, all structural plane abnormal regions and suspected abnormal parts in the rock mass are identified; Fusion of cross-hole elastic wave CT re-investigation data, all suspected abnormal parts are re-screened from the structural plane abnormal regions; According to the image of the new drill hole at each structural plane abnormal region, non-rock mass structural planes are excluded to obtain a set of rock mass structural planes, wherein the depth of the new drill hole is greater than the maximum depth of all structural plane abnormal regions; According to the characteristics of each rock mass structural plane in the set of rock mass structural planes, the combination degree of the corresponding rock mass structure is obtained, and the type and development degree of the rock mass structural plane are combined to determine the integrity of the rock mass.

2. The method for fine survey of the integrity of the rock mass covered by the foundation pit according to claim 1, characterized in that, According to the known geology of the set region, the geophysical detection line and the drill hole position are determined, and the high-density electrical method data and transient electromagnetic method data are combined to identify all suspected abnormal parts in the rock mass.

3. The method for fine survey of the integrity of a foundation pit covering rock mass according to claim 1, characterized in that, All suspected abnormal parts in rock mass are identified by using the first joint decision function; the first joint decision function is and its expression is: ； ； ； ； ； wherein, represents a high-density electrical method relative anomaly; represents a transient electromagnetic method relative anomaly rate; and are weight coefficients, and the sum of the two is 1; is a sliding background resistivity; is a high-density electrical method resistivity; is a transient electromagnetic method resistivity; is a background value; is a survey point coordinate; and are constants; when is greater than or equal to a first threshold value, it is determined that the location is a structural plane abnormal area; when is less than the first threshold value and greater than or equal to a second threshold value, it is determined that the location is a suspected abnormal part; wherein the second threshold value is less than the first threshold value; f 1 and f 2 are normalization functions.

4. The method for fine survey of the integrity of a foundation pit covering rock mass according to claim 1, characterized in that, Based on the high-density electrical method data and transient electromagnetic method data, the cross-hole elastic wave CT re-investigation data are further fused, and the second joint determination function is combined to re-screen the structural plane abnormal regions from all suspected abnormal parts.

5. The method for fine survey of the integrity of the rock mass covered by the foundation pit according to claim 4, characterized in that, Let the second joint decision function be whose expression is: ； ； ； ； ； ； wherein, represents high-density electrical method relative anomaly; represents transient electromagnetic method relative anomaly rate; represents elastic wave CT relative anomaly rate; represents wave velocity obtained by inversion based on cross-hole elastic wave CT technology at position x ; ( x ) represents background wave velocity value reflected by the area in which no abnormal wave velocity change occurs laterally within the same depth interval as point x ; , , are weight coefficients, and the sum of the three is 1; is a sliding background resistivity; is high-density electrical method resistivity; is transient electromagnetic method resistivity; is a background value; is a measurement point coordinate; , , are all constants; when is greater than or equal to a set threshold value, it is determined that an abnormal area of a structural plane exists at the position; f 1, f 2 and f 3 are normalization functions.

6. The method for fine survey of the integrity of a foundation pit covering rock mass according to claim 1, characterized in that, The development degree is represented by the number of structural plane groups and the average interval.

7. The method for fine survey of the integrity of a foundation pit covering rock mass according to claim 6, characterized in that, The determination process of the number of structural plane groups is as follows: According to the image of the new drill hole, the corresponding rock mass structural plane is fitted to obtain the corresponding occurrence parameters, which are converted into direction vectors on the corresponding unit sphere. The direction vector representation is clustered, the minimum spherical angle distance is used as the similarity index, and the direction aggregation cluster is identified to realize the grouping determination of the rock mass structural plane.

8. The method for fine survey of the integrity of a foundation pit covering rock mass according to claim 6, characterized in that, The calculation process of the average interval is as follows: The center point coordinates of each fitted plane in each group are extracted to form a set of center point coordinates. The unit normal vector of each rock mass structural plane is calculated, and its average direction is defined as the group normal vector and is unitized. Each center point in the set of center point coordinates is projected in the direction of the unitized group normal vector to obtain a normal distance sequence, which represents the spatial position of the rock mass structural plane in the direction of the group normal vector. All projection values are sorted from small to large, and the average interval of each group of rock mass structural planes is calculated according to the adjacent normal distance. According to the average interval and the number of structural plane groups of each group of rock mass structural planes, the weighted average method is used to obtain the equivalent average interval of all rock mass structural planes.

9. A system for fine surveying the integrity of a foundation pit covering rock mass, characterized in that, The method comprises the following steps: An abnormal preliminary screening module is used to identify all structural plane abnormal regions and suspected abnormal parts in the rock mass according to the known geology and existing drilling survey data of the set region; An abnormal re-screening module is used to fuse cross-hole elastic wave CT re-investigation data to re-screen structural plane abnormal regions from all suspected abnormal parts; A structural plane determination module is used to exclude non-rock mass structural planes according to the image of the new drill hole at each structural plane abnormal region to obtain a set of rock mass structural planes, wherein the depth of the new drill hole is greater than the maximum depth of all structural plane abnormal regions; An integrity determination module is used to obtain the combination degree of the corresponding rock mass structure according to the characteristics of each rock mass structural plane in the set of rock mass structural planes, and the type and development degree of the rock mass structural plane are combined to determine the integrity of the rock mass.

10. A device for fine surveying the integrity of a foundation covering rock mass, comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that, The processor implements the steps in the method for fine surveying the integrity of a foundation pit covering rock mass as claimed in any one of claims 1-8 when executing the program.

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