Active and passive source combined shield composite stratum excavation face interface identification method and system

Abstract

The invention provides an active and passive source combined shield composite stratum excavation face interface identification method and system. The method comprises the following steps: acquiring an active source excited elastic wave and a detection result reflected by a stratum change position; kirchhoff integral method offset is carried out on a detection result, a front stratum change position is determined, and an in-hole advanced geological detection result is obtained; a detection result caused by vibration generated by the shield hob is obtained, the detection result is filtered and decomposed, the hob vibration dominant frequency is extracted, lithology strength information is determined based on the vibration dominant frequency, and an in-hole near-field interface recognition result is obtained; and combining active source advanced detection and passive source interface detection to carry out progressive identification on the excavation surface. According to the method, shield excavation face stratum feature recognition can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of geological exploration, and in particular relates to an active and passive source combined shield composite stratum excavation face interface identification method and system. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] The shield method has become the mainstream construction method for rail transit construction due to its advantages such as high degree of mechanization, safety, high efficiency, environmental friendliness and low disturbance to the ground. Due to the wide distribution of cities in my country, shield tunneling passes through many different types of complex strata. Among them, composite strata have the characteristics of frequent changes in composite strata lithology, great disparity in rock strata physical and mechanical properties, and large differences in water content, making them one of the types of strata with high safety risks for shield tunneling. These characteristics make the construction control of composite strata very different from that of single strata, and the control requirements for shield tunneling are extremely high.

[0004] How to accurately identify the composite stratum characteristics of the excavation face and judge the shield tunneling status has become a key problem for safe shield tunneling. However, the shield is limited by the closed soil bin environment, making it difficult to directly observe the stratum characteristics of the excavation face. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a shield composite stratum excavation face interface recognition method and system combining active and passive sources. The present invention can realize the stratum feature recognition of the shield excavation face.

[0006] According to some embodiments, the present invention adopts the following technical solutions:

[0007] A shield composite stratum excavation face interface identification method combining active and passive sources, comprising the following steps:

[0008] Obtain the detection results of elastic waves excited by active sources and reflected at the place where the formation changes;

[0009] The detection results are processed by Kirchhoff integral migration imaging method, and the position of the stratum change ahead is determined to obtain the advanced geological exploration results in the cave.

[0010] Obtain the detection results caused by the vibration of the shield cutter, filter and decompose the detection results, extract the main frequency of the cutter vibration, determine the rock strength information based on the main frequency of vibration, and obtain the near-field interface identification results in the tunnel;

[0011] Active source advance detection and passive source interface detection are combined to progressively identify the excavation face.

[0012] As an optional implementation, the specific process of performing Kirchhoff integral method migration on the detection result includes:

[0013] The same detection space range and grid generation method as those used in velocity analysis are used, and each grid node is assumed to be a reflection point.

[0014] Based on the positional relationship between the source point, receiving point and transmitting point and the given surrounding rock wave velocity, the travel time under the current propagation path is calculated;

[0015] The corresponding instantaneous amplitude value is found according to the travel time between the source point and the receiving point, and the instantaneous amplitude at the same grid node is superimposed.

[0016] Furthermore, if a reflection point is a real interface position, the amplitude will reach a maximum value; otherwise, the superimposed amplitudes will approach zero.

[0017] As an optional implementation, the specific process of determining rock strength information based on the main vibration frequency includes: pre-constructing the relationship between the main vibration frequency and the rock strength according to historical data, and determining the corresponding rock strength information based on the current main vibration frequency according to the relationship.

[0018] As an optional implementation method, the specific process of progressively identifying the excavation face by combining active source advance detection and passive source interface detection includes: using advance detection to preliminarily confirm the stratum changes of the excavation face, constructing a rough shield tunneling advance detection geological model, and providing preliminary geological identification for shield tunneling;

[0019] Passive source interface detection is used as a supplementary means to active source advance detection. The results obtained by passive source interface detection supplement the excavation face geology determined by the rough shield tunneling advance detection geological model, and correct the subsequent shield tunneling geological conditions.

[0020] An active and passive source combined shield composite stratum excavation face interface identification system, comprising:

[0021] Active source advance detection unit, used to obtain detection results of elastic waves excited by active sources and reflected at the place where the formation changes;

[0022] Active source advance detection processing module, used to process the detection results by Kirchhoff integral migration imaging method, perform law migration, determine the position of the front stratum change, and obtain the advance geological detection results in the cave;

[0023] Passive source interface detection unit, used to obtain detection results caused by the vibration generated by the shield cutter;

[0024] The passive source interface detection processing module is used to filter and decompose the detection results, extract the main frequency of the roller cutter vibration, determine the rock strength information based on the main frequency of vibration, and obtain the near-field interface identification results in the tunnel;

[0025] The progressive joint interpretation module is used to progressively identify the excavation face by combining active source advance detection and passive source interface detection.

[0026] As an optional implementation, the active source advance detection unit includes a plurality of active source exciters and active source detectors. The active source exciters are arranged at the active source excitation points, and are used to hammer the shield segments to generate active source elastic waves as active source signals, which propagate forward through the reflection points of stratum changes to generate reflected waves that propagate from the surrounding rock in front of the shield to the rear of the shield, and are detected and collected by the active source detectors.

[0027] As an optional embodiment, the passive source interface detection unit includes a plurality of vibration sensors arranged on the cutter, which are used to obtain the vibration generated when the shield cutter enters the hard rock formation from the soft formation.

[0028] A computer-readable storage medium is used to store computer instructions, and when the computer instructions are executed by a processor, the steps in the above method are completed.

[0029] An electronic device comprises a memory and a processor, and computer instructions stored in the memory and executed on the processor. When the computer instructions are executed by the processor, the steps in the above method are completed.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The excavation face identification of the present invention is carried out synchronously with the shield machine excavation, and the shield machine does not need to be stopped for coordination, and does not occupy the shield machine excavation working time, which is conducive to giving full play to the working efficiency of the shield machine.

[0032] The present invention can fully improve the accuracy of excavation face interface recognition and relatively quickly and accurately obtain the changes in composite strata on the shield excavation face.

[0033] The present invention has good adaptability to shield tunnel construction and reduces the influence of factors such as metal in the tunnel on data collection.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0036] Figure 1 A flowchart of a method according to an embodiment;

[0037] Figure 2A layout diagram of equipment inside a shield machine according to an embodiment;

[0038] Figure 3 A schematic diagram of an active source detection method according to an embodiment. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0042] In the absence of conflict, the embodiments in this application and the features in the embodiments may be combined with each other.

[0043] Embodiment 1

[0044] A shield composite stratum excavation face interface identification method combining active and passive sources, such as Figure 1 As shown, the following steps are included:

[0045] (1) Obtain the detection results of elastic waves excited by the active source and reflected at the place where the stratum changes; use the Kirchhoff integral migration imaging method to perform imaging processing on the detection results, determine the location of the stratum change ahead, and obtain the advanced geological exploration results in the cave;

[0046] In this embodiment, the process of the Kirchhoff integral migration imaging method includes: 1) using the same detection space range and grid division method as the velocity analysis, and assuming that each grid node is a reflection point; 2) based on the positional relationship between the source point, the receiving point, and the transmitting point and the given surrounding rock wave velocity, the travel time under the propagation path can be obtained; 3) according to the travel time of the source point and the receiving point, the corresponding instantaneous amplitude value is found, and the instantaneous amplitude at the same grid node is superimposed. If the reflection point is the real interface position, the amplitude will have a maximum value. Otherwise, the superimposed amplitudes will approach zero.

[0047] (2) The vibration generated by the shield cutter during excavation is used as a passive source to obtain the detection results caused by the vibration generated by the shield cutter. The detection results are filtered and decomposed to extract the main frequency of the cutter vibration. The rock strength information is determined based on the main frequency of the vibration to obtain the near-field interface identification results of the shield excavation face.

[0048] In some embodiments, the relationship between the main vibration frequency and the lithology strength is pre-constructed based on historical data, and the corresponding lithology strength information is determined based on the current main vibration frequency according to the relationship.

[0049] (3) Combine active source advance detection and passive source interface detection to progressively identify the excavation face.

[0050] The excavation face is progressively identified by combining active source advance detection and passive source interface detection. The active source is used to stimulate advance detection to preliminarily confirm the stratum changes of the excavation face. A rough shield tunneling advance detection geological model is constructed through the imaging results of step (1), providing effective preliminary geological identification for shield tunneling. Passive source interface detection is used as a supplementary means for active source advance detection. The collected cutterhead vibration waveform is inverted and imaged through step (2) to display the geological conditions within the near field of the excavation face. Based on this, the aforementioned rough shield tunneling advance detection geological model is corrected to supplement the active source geological detection results, obtain more accurate composite stratum excavation interface identification, and effectively guide subsequent construction.

[0051] Embodiment 2

[0052] An active and passive source combined shield composite stratum excavation face interface identification system, comprising:

[0053] The active source advance detection unit is used to obtain the detection results of elastic waves excited by the active source and reflected at the place where the formation changes; in this embodiment, Figure 3 As shown, it includes an active source exciter 2-3 and an active source detector 3-5, wherein, as the shield advances, the active source exciter 2-3 hammers the shield segment at the active source excitation point 3-1 to generate an active source elastic wave 3-2 as an active source signal, which propagates forward through the formation change reflection point 3-3, and generates a reflected wave 3-4 which propagates from the surrounding rock in front of the shield to the rear of the shield, and is detected and collected by the active source detector 3-5.

[0054] Active source advance detection processing module, used to perform Kirchhoff integral method migration on the detection results, determine the position of the stratum change ahead, and obtain the advance geological detection results in the cave;

[0055] The passive source interface detection unit is used to obtain the detection result caused by the vibration generated by the shield cutter; in this embodiment, Figure 2As shown, during the tunneling process of the shield tunneling machine in the composite stratum, when the shield cutter 2-1 enters the hard rock stratum from the soft stratum, due to the change in the stratum properties, the shield cutter 2-1 will generate vibration under the same tunneling parameters, and the vibration sensor 2-5 arranged on the cutter will receive the vibration, filter and obtain the main frequency of the cutter vibration, and compare it to obtain the rock strength information.

[0056] The passive source interface detection processing module is used to filter and decompose the detection results, extract the main frequency of the roller cutter vibration, determine the rock strength information based on the main frequency of vibration, and obtain the near-field interface identification results in the tunnel;

[0057] The progressive joint interpretation module is used to progressively identify the excavation face by combining active source advance detection and passive source interface detection.

[0058] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0059] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0060] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0061] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made by those skilled in the art within the spirit and principle of the present invention without creative labor shall be included in the protection scope of the present invention.

Claims

1. A shield composite stratum excavation face interface identification method combining active and passive sources, characterized in that: The following steps are involved: Obtain the detection results of elastic waves excited by active sources and reflected at the place where the formation changes; The detection results are processed by Kirchhoff integral migration imaging method, and the position of the stratum change ahead is determined to obtain the advanced geological exploration results in the cave. Obtain the detection results caused by the vibration of the shield cutter, filter and decompose the detection results, extract the main frequency of the cutter vibration, determine the rock strength information based on the main frequency of vibration, and obtain the near-field interface identification results in the tunnel; Active source advance detection and passive source interface detection are combined to progressively identify the excavation face.

2. The method for identifying the interface of the shield composite stratum excavation face by combining active and passive sources as claimed in claim 1, characterized in that: The specific process of Kirchhoff integral method migration of the detection result includes: The same detection space range and grid generation method as those used in velocity analysis are used, and each grid node is assumed to be a reflection point. Based on the positional relationship between the source point, receiving point and transmitting point and the given surrounding rock wave velocity, the travel time under the current propagation path is calculated; The corresponding instantaneous amplitude value is found according to the travel time between the source point and the receiving point, and the instantaneous amplitude at the same grid node is superimposed.

3. The method for identifying the interface of the shield composite stratum excavation face by combining active and passive sources as claimed in claim 2, characterized in that: If a reflection point is a real interface position, the amplitude will reach a maximum value; otherwise, the superimposed amplitudes will approach zero.

4. The method for identifying the interface of the shield composite stratum excavation face by combining active and passive sources as claimed in claim 1, characterized in that: The specific process of determining the lithology strength information based on the main vibration frequency includes: pre-building the relationship between the main vibration frequency and the lithology strength according to historical data, and determining the corresponding lithology strength information based on the current main vibration frequency according to the relationship.

5. The method for identifying the interface of the shield composite stratum excavation face by combining active and passive sources as claimed in claim 1, characterized in that: The specific process of progressively identifying the excavation face by combining active source advance detection and passive source interface detection includes: using advance detection to preliminarily confirm the stratum changes of the excavation face, constructing a rough shield tunneling advance detection geological model, and providing preliminary geological identification for shield tunneling; Passive source interface detection is used as a supplementary means to active source advance detection. The results obtained by passive source interface detection supplement the excavation face geology determined by the rough shield tunneling advance detection geological model, and correct the subsequent shield tunneling geological conditions.

6. A shield composite stratum excavation face interface identification system combining active and passive sources, characterized in that: include: Active source advance detection unit, used to obtain detection results of elastic waves excited by active sources and reflected at the place where the formation changes; Active source advance detection processing module, used to process the detection results by Kirchhoff integral migration imaging method, perform law migration, determine the position of the front stratum change, and obtain the advance geological detection results in the cave; Passive source interface detection unit, used to obtain detection results caused by the vibration generated by the shield cutter; The passive source interface detection processing module is used to filter and decompose the detection results, extract the main frequency of the roller cutter vibration, determine the rock strength information based on the main frequency of vibration, and obtain the near-field interface identification results in the tunnel; The progressive joint interpretation module is used to progressively identify the excavation face by combining active source advance detection and passive source interface detection.

7. The active and passive combined shield composite stratum excavation face interface identification system as claimed in claim 6, characterized in that: The active source advance detection unit includes a plurality of active source exciters and active source detectors. The active source exciters are arranged at the active source excitation points and are used to hammer the shield segments to generate active source elastic waves as active source signals, which propagate forward through the reflection points of stratum changes to generate reflected waves that propagate from the surrounding rock in front of the shield to the rear of the shield and are detected and collected by the active source detectors.

8. The active and passive combined shield composite stratum excavation face interface identification system as claimed in claim 6, characterized in that: The passive source interface detection unit includes a plurality of vibration sensors arranged on the cutter, which are used to obtain the vibration generated when the shield cutter enters the hard rock formation from the soft formation.

9. A computer-readable storage medium, characterized in that: Used to store computer instructions, which, when executed by a processor, complete the steps of the method according to any one of claims 1 to 5.

10. An electronic device comprising a memory and a processor and computer instructions stored in the memory and executed on the processor, wherein when the computer instructions are executed by the processor, the steps of the method according to any one of claims 1 to 5 are completed.

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