Shield tunnel construction safety risk identification method based on stratum digital structure

Abstract

The invention provides a shield tunnel construction safety risk identification method based on a stratum digital structure, and the method comprises the steps: obtaining a three-dimensional coordinate of a target tunnel axis, constructing a shield tunnel stratum digital structure based on the three-dimensional coordinate, and building a shield tunnel construction safety risk list; on the basis of a stratum digital structure, according to the shield tunnel propelling condition, actually measuring and obtaining the solid size and position axis coordinates of a shield tail and a cutterhead of a shield tunneling machine; calculating coordinates of feature points of the shield tunneling machine based on solid sizes and position axis coordinates of a shield tail and a cutterhead of the shield tunneling machine, and judging a stratum where the shield tunneling machine is located; and according to the stratum obtained by judgment, associating a risk list, and identifying a security risk. According to the method, the influence caused by stratum change is fully considered; a risk list associated with the stratum is constructed, so that the risk condition change caused by the stratum change can be quickly mastered; risks and hidden dangers in the shield construction period are managed and controlled in a targeted mode, continuous updating and iteration can be conducted according to experience knowledge, and the control capacity of the risks and hidden dangers is improved.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction safety risk assessment technology, specifically to a method for identifying safety risks in shield tunnel construction based on a geological digital structure, and also to a corresponding system, computer terminal, and computer-readable storage medium. Background Technology

[0002] Shield tunneling, a commonly used tunnel construction technique, is characterized by its high degree of concealment and dynamic nature. During construction, it often faces risks due to uncertainties in the geological formation, leading to problems such as failure of the main drive seal of the tunnel boring machine (TBM), failure of the shield seal, and damage to tunnel segments. These issues can even result in accidents such as the TBM being unable to advance, tunnel collapse, ground subsidence, and damage to surrounding facilities, causing adverse consequences such as project delays, economic losses, and personal injury. Therefore, TBM tunnel construction must fully understand geological information, adjust TBM construction parameters accordingly, and dynamically identify and assess safety risks to provide a basis for TBM tunnel construction and ensure project safety.

[0003] However, there is a lack of an effective safety risk identification technology for shield tunnel construction in the existing technology. At present, no descriptions or reports of technologies similar to this invention have been found, and similar information at home and abroad has not been collected. Summary of the Invention

[0004] To address the aforementioned shortcomings in the prior art, this invention provides a method for identifying safety risks in shield tunnel construction based on a digital geological structure, along with a corresponding system, computer terminal, and computer-readable storage medium.

[0005] According to a first aspect of the present invention, a method for identifying safety risks in shield tunnel construction based on digital geological structures is provided, comprising: Obtain the three-dimensional coordinates of the target tunnel axis, construct the digital structure of the geological strata of the shield tunnel based on the three-dimensional coordinates, and establish a safety risk list for shield tunnel construction. Based on the aforementioned geological digital structure, and according to the tunnel boring machine's progress, the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine were obtained by actual measurement. Based on the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine, the coordinates of the characteristic points of the tunnel boring machine are calculated, and the soil layer in which it is located is determined. Based on the determined soil layers, the risk list is associated with them to identify safety risks.

[0006] Preferably, the three-dimensional coordinates of the target tunnel axis are obtained, and based on the three-dimensional coordinates, a digital structure of the geological formation of the shield tunnel is constructed, and a safety risk list for shield tunnel construction is established, including: Based on the tunnel design parameters, and using the national or urban coordinate system, the three-dimensional coordinate system of the shield tunnel axis point P is constructed as follows: In the formula, shaft and The axes are the plane coordinate axes of the national geodetic coordinate system or the city coordinate system, respectively. The axis is a vertically upward coordinate axis, based on the level elevation. The distances are tunnel axis mileage, all in meters; A digital model of the geological strata for the shield tunnel was constructed using the tunnel axis as a reference. Based on the aforementioned geological digital model, a geological digital structure is constructed using data from engineering exploration boreholes. This structure includes soil layer number, soil layer name, soil layer spatial coordinates, groundwater level, and soil layer physical and mechanical properties. For borehole number i, the spatial coordinates at the borehole opening at the surface are: The spatial coordinates of the k-th soil layer in borehole i are: The spatial coordinates of the bottom of the kth soil layer in borehole i are: Then the thickness of the kth soil layer in borehole i for: Given the coordinates of the surface point j of interest Then its planar distance from the surface opening of borehole i is... for: The soil layers in the geological body are mainly distributed in horizontal layers, and a planar distance weight is introduced. To calculate the top elevation of soil layers at different locations; horizontal distance weighting. In Gaussian form, it is expressed as: In the formula, The standard deviation parameter of the Gaussian function; This represents the maximum planar distance between adjacent exploration boreholes. Based on the drilling data from the engineering survey, using surface point j Centered on, with Find exploration boreholes for the plane radius; if the total number of exploration boreholes found is Calculate the planar distance between each surface point j and the surface opening of the found exploration borehole l. and distance weight The calculation formula is as follows: , Calculate surface point j Vertical profile, elevation of soil layer k Elevation of the bottom layer They are respectively: In the formula, To determine the elevation of the kth soil layer in the vertical profile of borehole l, To investigate the elevation of the bottom of the kth soil layer in the vertical profile of borehole l, The sum of the planar distance weights is given by the following formula: For point p in the digital model of the strata of a shield tunnel located on the same vertical section as point j on the ground surface, its spatial coordinates are: Based on the calculated elevation of the soil layer in the vertical profile, determine point p. If the location of point p in the soil layer satisfies the following formula, then point p is located in the m-th soil layer: In the formula, Let m be the elevation of the m-th soil layer in the vertical profile of point j on the ground surface. The elevation of the bottom of the m-th soil layer in the vertical profile of point j on the ground surface; Constructing a safety risk list for shield tunnel construction based on a geological digital model for: In the formula: Slayer represents the soil layer parameter; Risk represents the construction risk parameter; Based on the engineering survey results, establish the correspondence between the soil layer number and the soil layer parameter Slayer in the geological digital model of the risk list.

[0007] Preferably, the spatial dimensions of the digital model of the shield tunnel strata are: based on the tunnel axis, extending forward and backward by distances L0 and L1 along the starting and ending points. n The following parameters are defined as follows: 1) Twice the tunnel diameter and not less than a set threshold a; 2) The horizontal extension width B of the tunnel axis is three times the tunnel diameter and not less than a set threshold b; 3) The vertical downward extension depth H of the tunnel axis is twice the tunnel diameter and not less than a set threshold c; 4) The axis extends vertically upward to the ground or water surface.

[0008] Preferably, the soil layer parameter Slayer includes: soft cohesive soil layer, hard cohesive soil layer, loose sandy soil layer, dense sandy soil layer, gravelly soil layer, weathered rock layer, composite layer, toxic and harmful gas layer, boulder-containing layer, and underground obstacle layer. The construction risk parameters include: soil instability at the tunnel face, tunnel boring machine subsidence, failure of the main drive seal, water spraying and quicksand from the auger, inability of the cutterhead to rotate, inability of the tunnel boring machine to advance, water leakage at the tail of the shield, grout leakage and quicksand, segment rupture and water leakage, and ground subsidence and damage to surrounding facilities.

[0009] Preferably, based on the aforementioned geological digital structure, and according to the tunnel boring machine's (TBM) progress, the physical dimensions and position axis coordinates of the TBM tail and cutterhead are measured and obtained, including: Based on the aforementioned geological digital structure, the tunnel axis, shield tail, and cutterhead dimensions are acquired in real time according to the changes in the tunnel boring machine's (TBM) forward position; wherein, the TBM dimensions include: the distance between the shield tail and the cutterhead. Shield tail and cutter head diameter , And the actual measured center of the shield cutterhead and the center of the shield tail From the position coordinates, we obtain the position axis coordinates.

[0010] Preferably, based on the axial coordinates of the shield tail and cutterhead positions of the tunnel boring machine (TBM), the coordinates of the TBM's characteristic points are calculated, and the soil layer in which it is located is determined, including: Based on the actual measurement of the shield cutterhead center and the center of the shield tail Position coordinates and Calculate the feature points of the tunnel boring machine The coordinates include: set up: Then we have: Based on the knowledge of solid geometry, we can deduce that: Upper feature points of the shield tail for: Feature point on the left side of the shield tail for: Feature point on the right side of the shield tail for: Lower feature points of the shield tail for: Upper feature points of the cutter head for: Feature points on the left side of the cutter head for: Feature points on the right side of the cutter head for: Lower feature points of the cutter head for: In the formula, This refers to the distance between the shield tail and the cutterhead of the tunnel boring machine. , The diameter of the shield tail and the cutterhead; Based on the calculated coordinates of the tunnel boring machine's feature points, and in conjunction with the aforementioned geological digital structure, the soil layer number of each feature point is determined.

[0011] Preferably, based on the determined soil layers, the risk list is associated to identify safety risks, including: Based on the determined soil layers, identify the construction risk parameter Risk in the risk list and issue a risk warning.

[0012] Preferably, it further includes: updating the safety risk list for shield tunnel construction based on the dynamic information of shield tunnel construction and the identified construction safety risk information. .

[0013] According to a second aspect of the present invention, a shield tunnel construction safety risk identification system based on geological digital structure is provided, comprising: The geological model construction module is used to obtain the three-dimensional coordinates of the target tunnel axis, construct the digital geological structure of the shield tunnel based on the three-dimensional coordinates, and establish a safety risk list for shield tunnel construction. The entity data acquisition module, based on the aforementioned geological digital structure, measures and acquires the entity dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine according to the tunnel's advancement. The feature point calculation module calculates the coordinates of the feature points of the tunnel boring machine (TBM) based on the physical dimensions and position axis coordinates of the shield tail and cutterhead, and determines the soil layer in which it is located. The safety risk identification module is used to identify safety risks by associating the identified soil layers with the risk list.

[0014] According to a third aspect of the present invention, a computer terminal is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, can be used to perform the method described in any one of the above inventions.

[0015] According to a fourth aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, can be used to perform the method described in any one of the above inventions.

[0016] By adopting the above technical solution, the present invention has at least one of the following beneficial effects compared with the prior art: The method for identifying safety risks in shield tunnel construction based on geological digital structure provided by this invention infers the geological information of the target location based on the geological information of the actual exploration borehole. This method differs from the existing technology that relies solely on interpolation or empirical judgment based on the actual exploration borehole information, and fully considers the impact of geological changes.

[0017] The present invention provides a method for identifying safety risks in shield tunnel construction based on geological digital structure. It constructs a risk list associated with the geological strata, establishes a correspondence between different geological conditions and specific risk types that may be caused during shield tunnel construction, and can quickly grasp the changes in risk caused by geological changes.

[0018] The method for identifying safety risks in shield tunnel construction based on geological digital structure provided by this invention can effectively manage and control potential risks during shield construction, and can be continuously updated and iterated based on experience and knowledge to improve the ability to control potential risks. Attached Figure Description

[0019] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a flowchart illustrating the workflow of a shield tunnel construction safety risk identification method based on geological digital structure in a preferred embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the components of a shield tunnel construction safety risk identification system based on a geological digital structure in a preferred embodiment of the present invention.

[0021] Figure 3 This is a schematic diagram of the coordinates of tunnel axis point P in a preferred embodiment of the present invention.

[0022] Figure 4 This is a schematic diagram of the geological strata of a shield tunnel in a preferred embodiment of the present invention.

[0023] Figure 5 This is a schematic diagram of feature point coordinates in a preferred embodiment of the present invention.

[0024] Figure 6 This is a flowchart illustrating the process of identifying safety risks in shield tunnel construction in a specific application example of the present invention.

[0025] Figure 7 Figures (a) to (c) are schematic diagrams showing the locations of engineering survey drilling holes and tunnel boring machines in a specific application example of the present invention. Detailed Implementation

[0026] The embodiments of the present invention are described in detail below: These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention.

[0027] Shield tunneling construction requires a thorough understanding of geological conditions, adjustment of tunneling parameters, and dynamic identification and assessment of safety risks to provide a basis for construction and ensure project safety. However, existing technologies lack an effective safety risk identification technique for shield tunneling construction.

[0028] To address the aforementioned issues, one embodiment of the present invention provides a method for identifying safety risks in shield tunnel construction based on a digital geological structure. This method can infer the geological information of the target location based on the geological information from the actual exploration borehole, fully considering the impact of geological changes; it constructs a risk list associated with the geological strata, enabling rapid understanding of changes in risk conditions caused by geological variations, targeted control of potential risks during shield tunnel construction, and continuous updates and iterations based on experience and knowledge to improve the ability to control potential risks.

[0029] Specifically, such as Figure 1 As shown in the embodiment, the method for identifying safety risks in shield tunnel construction based on digital geological structures can include: S1. Obtain the three-dimensional coordinates of the target tunnel axis. Based on the three-dimensional coordinates, construct the digital structure of the shield tunnel strata and establish a safety risk list for shield tunnel construction. S2, based on the geological digital structure, obtains the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine according to the tunnel's progress. S3, based on the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine, calculate the coordinates of the characteristic points of the tunnel boring machine and determine the soil layer in which it is located; S4. Based on the determined soil layers, associate them with the risk list and identify safety risks.

[0030] The technical solutions provided by the above embodiments of the present invention will be further described in detail below with reference to preferred embodiments.

[0031] In some preferred embodiments, S1, which involves obtaining the three-dimensional coordinates of the target tunnel axis, constructing a digital structure of the geological formation of the shield tunnel based on the three-dimensional coordinates, and establishing a safety risk list for shield tunnel construction, may further include: S11, based on the tunnel design parameters and using the National Geodetic Coordinate System (CGCS2000) or urban coordinate system, construct a three-dimensional coordinate system for the shield tunnel axis point P, such as... Figure 3 As shown: in, shaft and The axes are the plane coordinate axes of the national geodetic coordinate system or the city coordinate system, respectively. The axis is vertically upward, and the level is used as the reference. The distances are tunnel axis mileage, all in meters.

[0032] S12, using the tunnel axis as a reference, constructs a digital model of the geological strata for the shield tunneling method, such as... Figure 4 As shown, the spatial dimensions of the geological digital model are as follows: along the tunnel axis, the extension distances L0 and Ln before and after the starting and ending mileages are 2 times the tunnel diameter and not less than a set threshold a (e.g., 20m); the horizontal extension width B of the tunnel axis is 3 times the tunnel diameter and not less than a set threshold b (e.g., 50m); the vertical downward extension depth H of the tunnel axis is 2 times the tunnel diameter and not less than a set threshold c (e.g., 30m); the axis extends vertically upward to the ground or water surface.

[0033] S13. Based on the drilling data from the engineering survey, construct a digital stratigraphic structure. This structure includes soil layer number, layer name, spatial coordinates of the soil layer, groundwater level, and physical and mechanical properties of the soil layer. For borehole number i, the spatial coordinates at the borehole opening are... The spatial coordinates of the k-th soil layer in borehole i are: The spatial coordinates of the bottom of the kth soil layer in borehole i are: Then the thickness of the kth soil layer in borehole i is: S14, Given the coordinates of the surface point j of interest. Then its planar distance from the surface opening of borehole i is... for: The soil layers in the geological body are mainly distributed in horizontal layers, and a planar distance weight is introduced. To calculate the top elevation of the soil layer at different locations. Planar distance weighting. In Gaussian form, it is expressed as: In the formula: The standard deviation parameter of the Gaussian function is determined comprehensively based on factors such as site topography, geology, and exploration boreholes. This represents the maximum planar distance between adjacent exploration boreholes.

[0034] S15, based on the drilling data from the engineering survey, using surface point j Centered on, with Locate exploration boreholes for a given plane radius. If the total number of exploration boreholes found is... According to S14, the planar distance and distance weight between the surface point j and the surface borehole opening of the found exploration borehole l are calculated one by one, as follows: , S16, Calculate surface point j Vertical profile, elevation of soil layer k Elevation of the bottom layer for: In the formula, To determine the elevation of the kth soil layer in the vertical profile of borehole l, To investigate the elevation of the bottom of the kth soil layer in the vertical profile of borehole l, This is the sum of the planar distance weights; where: S17, for point p in the digital model of the strata of a shield tunnel located on the same vertical section as point j on the ground surface, its spatial coordinates are: Based on the vertical profile soil layer elevation calculated from S16, point p can be used. If the location of point p in the soil layer satisfies the following formula, then point p is located in the m-th soil layer: In the formula, Let m be the elevation of the m-th soil layer in the vertical profile of point j on the ground surface. The elevation of the bottom of the m-th soil layer in the vertical profile of point j on the ground surface; S18, Construct a safety risk list for shield tunnel construction based on a digital geological model: In the formula: Slayer represents the soil layer parameter, which consists of the following parameters: Soft, cohesive soil layers; Stiff, cohesive soil layers; Loose sandy soil strata; Dense sandy soil layer; Gravelly soil layers: boulders / cobblestones, pebbles / gravel, rounded gravel / angular gravel; Weathered rock strata; Composite strata: soft upper layer and hard lower layer composite strata; hard upper layer and soft lower layer composite strata; Formations containing toxic and harmful gases; Strata containing isolated boulders; Underground obstacle strata; In the formula, Risk is a construction risk parameter, which consists of the following parameters: Soil instability at the excavation face; The tunnel boring machine subsided; Main drive seal failure; Spiral excavator sprays water and quicksand; The cutter head cannot rotate; The tunnel boring machine could not advance; Water leakage, grout leakage, and sand flow at the shield tail; Segment rupture and leakage; Ground subsidence and damage to surrounding facilities; Based on the engineering survey results, establish the correspondence between the soil layer numbers in the geological digital model and the soil layer parameters in the Slayer in the risk list.

[0035] In some preferred embodiments, S2 above, based on the geological digital structure and according to the tunnel boring machine's advancement, may further include obtaining the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine through actual measurement, and may also include: Based on the geological digital structure, the tunnel axis, shield tail, and cutterhead dimensions are acquired in real time according to the changes in the tunnel boring machine's (TBM) forward position. The TBM dimensions include the distance between the shield tail and the cutterhead. The diameters of the shield tail and the cutterhead are respectively , Based on the tunnel axis and the physical dimensions of the tunnel boring machine, the center of the cutterhead was actually measured. and the center of the shield tail From the position coordinates, we obtain the position axis coordinates.

[0036] In some preferred embodiments, S3, which calculates the coordinates of the tunnel boring machine's characteristic points and determines the soil layer based on the axial coordinates of the shield tail and cutterhead, may further include: S31, based on the coordinates of the two center points , Calculate the feature points of the tunnel boring machine coordinates, such as Figure 5 As shown, the coordinates of the feature points are as follows: set up: Then we have: Based on the knowledge of solid geometry, we can deduce that: Upper feature points of the shield tail for: Feature point on the left side of the shield tail for: Feature point on the right side of the shield tail for: Lower feature points of the shield tail for: Upper feature points of the cutter head for: Feature points on the left side of the cutter head for: Feature points on the right side of the cutter head for: Lower feature points of the cutter head for: S32, Coordinates of the tunnel boring machine feature points obtained from measurements and calculations in S31. , , , , , , , By combining the stratigraphic digital structure obtained from S14 to S17, the soil layer (i.e., stratum) number where the feature point is located can be determined.

[0037] In some preferred embodiments, the above-mentioned S4, which identifies safety risks based on the determined soil layer and associated risk list, may further include: Based on the determined soil layer (i.e. stratum), and combined with the construction risk parameter Risk used in S18 to identify the characteristic points of the tunnel boring machine, a risk warning is issued to achieve automatic identification and early warning of safety risks in tunnel construction using the shield method.

[0038] In some preferred embodiments, the above method further includes: Based on the dynamic information of shield tunnel construction (i.e., based on the progress of the shield tunnel, the actual dimensions and position axis coordinates of the shield tail and cutterhead are obtained by measurement, and the coordinates of the shield machine's feature points are calculated, and then the soil layer number of each feature point is calculated to determine the soil layer where the feature point is located) and construction safety risk information, the safety risk list for shield tunnel construction is updated. On-site personnel can conduct targeted safety management based on the risk list.

[0039] Based on the same inventive concept, an embodiment of the present invention also provides a shield tunnel construction safety risk identification system based on geological digital structure.

[0040] Specifically, such as Figure 2 As shown in the figure, the shield tunnel construction safety risk identification system based on geological digital structure provided in this embodiment may include: The geological model construction module is used to obtain the three-dimensional coordinates of the target tunnel axis, construct the digital geological structure of the shield tunnel based on the three-dimensional coordinates, and establish a safety risk list for shield tunnel construction. The entity data acquisition module, based on the geological digital structure, measures and acquires the entity dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine according to the tunnel's progress. The feature point calculation module calculates the coordinates of the tunnel boring machine's feature points based on the physical dimensions and position axis coordinates of the shield tail and cutterhead, and determines the soil layer in which it is located. The safety risk identification module is used to identify safety risks by associating the identified soil layers with a risk list.

[0041] It should be noted that the steps in the method provided by the present invention can be implemented using corresponding modules, devices, units, etc. in the system. Those skilled in the art can refer to the technical solution of the method to realize the composition of the system. That is, the embodiments in the method can be understood as preferred examples for building the system, and will not be elaborated here.

[0042] An embodiment of the present invention also provides a computer terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it can be used to perform any of the methods described in the above embodiments of the present invention.

[0043] Optionally, the memory is used to store programs; the memory may include volatile memory, such as random-access memory (RAM), such as static random-access memory (SRAM), double data rate synchronous dynamic random-access memory (DDR SDRAM), etc.; the memory may also include non-volatile memory, such as flash memory. The memory is used to store computer programs (such as application programs and functional modules that implement the above methods), computer instructions, etc., and the aforementioned computer programs and computer instructions can be partitioned and stored in one or more memories. Furthermore, the aforementioned computer programs, computer instructions, data, etc., can be accessed by the processor.

[0044] A processor is used to execute computer programs stored in memory to implement the various steps of the methods or various modules of the systems involved in the above embodiments. For details, please refer to the relevant descriptions in the preceding method and system embodiments.

[0045] The processor and memory can be separate structures or integrated structures. When the processor and memory are separate structures, they can be coupled together via a bus.

[0046] An embodiment of the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, can be used to perform the method of any of the above embodiments of the present invention.

[0047] Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of computer programs from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Alternatively, the ASIC can reside in a user device. Of course, the processor and storage medium can also exist as discrete components in a communication device.

[0048] The technical solution provided by the above embodiments of the present invention will be further described in detail below with reference to a specific application example.

[0049] like Figure 6 As shown, the method for identifying safety risks in shield tunnel construction based on digital geological structures, as illustrated in this specific application example, includes the following steps: Step 1: Based on the National Geodetic Coordinate System (CGCS2000) and tunnel design parameters, obtain the three-dimensional coordinates of the target tunnel axis.

[0050] The three-dimensional coordinates of the target tunnel axis should include the starting point and ending point of the axis, with intermediate points selected at different intervals depending on the complexity of the geological formation. A geological digital model space should be established based on the tunnel axis. The spatial dimensions of the geological digital model are: based on the tunnel axis direction, extending forward and backward by distances L0 and L1 along the starting and ending points. n The following dimensions are defined as follows: 1) Tunnel axis extending horizontally outwards at a depth of 20m and 3 times the tunnel diameter, and 2) Tunnel axis extending vertically downwards at a depth of 30m and 3) Tunnel axis extending vertically upwards to the ground or water surface.

[0051] Furthermore, a geological digital model is established based on the engineering exploration borehole data. The engineering exploration borehole data may include borehole location, soil layer number, layer name, and spatial coordinates of the soil layer, and may also include groundwater level elevation, soil physical and mechanical properties, etc. This embodiment of the invention does not specifically limit these details.

[0052] Step 2: Based on the progress of the tunnel boring machine (TBM), the axial coordinates of the shield tail and cutterhead positions are measured. In this specific application example, the specific parameters for a certain segment during tunnel advancement are given. This refers to the location of the shield cutterhead. This is the tail position of the tunnel boring machine (TBM). The TBM is 12m long and has a radius of 5m. A and B are known exploration boreholes. Figure 7 As shown in (a) to (c), this specific application example provides... Given coordinates (-11020.5, 32416.2, -8), with the tunnel boring machine in a horizontal direction, then: Step 3: Calculate the coordinates of the feature points based on the tunnel boring machine's orientation and known coordinates. In this embodiment, the feature points on the upper part of the tunnel boring machine's cutterhead are calculated. Coordinates and lower feature points That is: Furthermore, by combining the known soil layer information at boreholes A and B, the characteristic points on the upper part of the shield cutterhead can be derived. With lower feature points Soil layer information. In this embodiment, the bottom elevation of the third soil layer in borehole A is -8.04m, and the bottom elevation of the fourth soil layer is -18.54m; the bottom elevation of the third soil layer in borehole B is -5.74m, and the bottom elevation of the fourth soil layer is -18.54m. The surface point can be calculated. The planar distance and distance weight between the found exploration boreholes A and B, where This can be obtained by calculating the standard deviation of the distance from the expected value, which is: Substitute into the calculation to reach the surface point The soil elevations of layers ③ and ④ are as follows: Then the feature points on the upper part of the shield cutterhead can be determined. With lower feature points The soil layer in which it is located, , Therefore, the feature points on the lower part of the shield cutterhead can be determined. Located in layer 4, the upper feature point of the shield cutterhead Further judgment is needed based on the data from the second soil layer.

[0053] Step 4, based on the feature points of the lower part of the shield cutterhead The information that it is located in the 4th layer, combined with the information in the survey report that the soil in the 4th layer is gray silty clay, and the groundwater level, indicates that its risk list includes [tunnel boring machine subsidence, ground subsidence and damage to surrounding facilities], thus serving as a warning about the risks on site.

[0054] Step 5: As the tunnel boring machine advances further, a new assessment is conducted to identify dynamic risks.

[0055] Any matters not covered in the above embodiments of the present invention are well-known in the art.

[0056] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A method for identifying safety risks in shield tunnel construction based on geological digital structure, characterized in that, include: Obtain the three-dimensional coordinates of the target tunnel axis, construct the digital structure of the geological strata of the shield tunnel based on the three-dimensional coordinates, and establish a safety risk list for shield tunnel construction. Based on the aforementioned geological digital structure, and according to the tunnel boring machine's progress, the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine were obtained by actual measurement. Based on the physical dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine, the coordinates of the characteristic points of the tunnel boring machine are calculated, and the soil layer in which it is located is determined. Based on the determined soil layers, the risk list is associated with them to identify safety risks.

2. The method for identifying safety risks in shield tunnel construction based on digital geological structures according to claim 1, characterized in that, Obtain the three-dimensional coordinates of the target tunnel axis. Based on these coordinates, construct a digital geological structure of the shield tunnel and establish a safety risk list for shield tunnel construction, including: Based on the tunnel design parameters, and using the national or urban coordinate system, the three-dimensional coordinate system of the shield tunnel axis point P is constructed as follows: In the formula, shaft and The axes are the plane coordinate axes of the national geodetic coordinate system or the city coordinate system, respectively. The axis is a vertically upward coordinate axis, based on the level elevation. The distances are tunnel axis mileage, all in meters; A digital model of the geological strata of the shield tunnel was constructed using the tunnel axis as a reference. Based on the aforementioned geological digital model, a geological digital structure is constructed using data from engineering exploration boreholes. This structure includes soil layer number, soil layer name, soil layer spatial coordinates, groundwater level, and soil layer physical and mechanical properties. For borehole number i, the spatial coordinates at the borehole opening at the surface are: The spatial coordinates of the k-th soil layer in borehole i are: The spatial coordinates of the bottom of the kth soil layer in borehole i are: The thickness of the kth soil layer in borehole i is... for: Given the coordinates of the surface point j of interest Then its planar distance from the surface opening of borehole i is... for: The soil layers in the geological body are mainly distributed in horizontal layers, and a planar distance weight is introduced. To calculate the top elevation of soil layers at different locations; horizontal distance weighting. In Gaussian form, it is expressed as: In the formula, The standard deviation parameter of the Gaussian function; This represents the maximum planar distance between adjacent exploration boreholes. Based on the drilling data from the engineering survey, using surface point j Centered on, with Find exploration boreholes for the plane radius; if the total number of exploration boreholes found is Calculate the planar distance between each surface point j and the surface opening of the found exploration borehole l. and distance weight The calculation formula is as follows: ， Calculate surface point j Vertical profile, elevation of soil layer k Elevation of the bottom layer They are respectively: In the formula, To determine the elevation of the kth soil layer in the vertical profile of borehole l, To investigate the elevation of the bottom of the kth soil layer in the vertical profile of borehole l, The sum of the planar distance weights is given by the following formula: For point p in the digital model of the strata of a shield tunnel located on the same vertical section as point j on the ground surface, its spatial coordinates are: Based on the calculated elevation of the soil layer in the vertical profile, determine point p. If the location of point p in the soil layer satisfies the following formula, then point p is located in the m-th soil layer: In the formula, Let m be the elevation of the m-th soil layer in the vertical profile of point j on the ground surface. The elevation of the bottom of the m-th soil layer in the vertical profile of point j on the ground surface; Constructing a safety risk list for shield tunnel construction based on a geological digital model for: In the formula: Slayer represents the soil layer parameter; Risk represents the construction risk parameter; Based on the engineering survey results, establish the correspondence between the soil layer number and the soil layer parameter Slayer in the geological digital model of the risk list.

3. The method for identifying safety risks in shield tunnel construction based on digital geological structures according to claim 2, characterized in that, The spatial dimensions of the shield tunnel geological digital model are as follows: based on the tunnel axis, the distances extending forward and backward along the starting and ending points are L0 and L1. n The following values ​​are respectively: 2 times the tunnel diameter and not less than the set threshold a; the horizontal extension width B of the tunnel axis is 3 times the tunnel diameter and not less than the set threshold b; the vertical downward extension depth H of the tunnel axis is 2 times the tunnel diameter and not less than the set threshold c. The axis extends vertically upwards to the ground or water surface; The soil layer parameter Slayer includes: soft cohesive soil layer, hard cohesive soil layer, loose sandy soil layer, dense sandy soil layer, gravelly soil layer, weathered rock layer, composite layer, toxic and harmful gas layer, boulder-containing layer, and underground obstacle layer. The construction risk parameters include: soil instability at the tunnel face, tunnel boring machine subsidence, failure of the main drive seal, water spraying and quicksand from the auger, inability of the cutterhead to rotate, inability of the tunnel boring machine to advance, water leakage at the tail of the shield, grout leakage and quicksand, segment rupture and water leakage, and ground subsidence and damage to surrounding facilities.

4. The method for identifying safety risks in shield tunnel construction based on digital geological structures according to claim 1, characterized in that, Based on the aforementioned geological digital structure, and according to the tunnel boring machine's (TBM) advancement, the physical dimensions and position axis coordinates of the TBM tail and cutterhead are measured, including: Based on the aforementioned geological digital structure, the tunnel axis, shield tail, and cutterhead dimensions are acquired in real time according to the changes in the tunnel boring machine's (TBM) forward position; wherein, the TBM dimensions include: the distance between the shield tail and the cutterhead. Shield tail and cutter head diameter , And the actual measured center of the shield cutterhead and the center of the shield tail From the position coordinates, we obtain the position axis coordinates.

5. The method for identifying safety risks in shield tunnel construction based on digital geological structures according to claim 1, characterized in that, Based on the coordinates of the shield tail and cutterhead positions of the tunnel boring machine (TBM), the coordinates of the TBM's characteristic points are calculated, and the soil layer in which it is located is determined, including: Based on the actual measurement of the shield cutterhead center and the center of the shield tail Position coordinates and Calculate the feature points of the tunnel boring machine The coordinates include: set up: Then we have: Based on the knowledge of solid geometry, we can deduce that: Upper feature points of the shield tail for: Feature point on the left side of the shield tail for: Feature point on the right side of the shield tail for: Lower feature points of the shield tail for: Upper feature points of the cutter head for: Feature points on the left side of the cutter head for: Feature points on the right side of the cutter head for: Lower feature points of the cutter head for: In the formula, This refers to the distance between the shield tail and the cutterhead of the tunnel boring machine. , The diameter of the shield tail and the cutterhead; Based on the calculated coordinates of the tunnel boring machine's feature points, and in conjunction with the aforementioned geological digital structure, the soil layer number of each feature point is determined.

6. The method for identifying safety risks in shield tunnel construction based on digital geological structures according to claim 1, characterized in that, Based on the determined soil layers, the aforementioned risk list is used to identify safety risks, including: Based on the determined soil layers, identify the construction risk parameter Risk in the risk list and issue a risk warning.

7. The method for identifying safety risks in shield tunnel construction based on digital geological structures according to claim 6, characterized in that, Also includes: The list of safety risks for shield tunnel construction is updated based on dynamic information on shield tunnel construction and identified construction safety risks. .

8. A safety risk identification system for shield tunnel construction based on geological digital structure, characterized in that, include: The geological model construction module is used to obtain the three-dimensional coordinates of the target tunnel axis, construct the digital geological structure of the shield tunnel based on the three-dimensional coordinates, and establish a safety risk list for shield tunnel construction. The entity data acquisition module, based on the aforementioned geological digital structure, measures and acquires the entity dimensions and position axis coordinates of the shield tail and cutterhead of the tunnel boring machine according to the tunnel's advancement. The feature point calculation module calculates the coordinates of the feature points of the tunnel boring machine (TBM) based on the physical dimensions and position axis coordinates of the shield tail and cutterhead, and determines the soil layer in which it is located. The safety risk identification module is used to identify safety risks by associating the identified soil layers with the risk list.

9. A computer terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it can be used to perform the method of any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program can be used to perform the method of any one of claims 1-7.

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