A geological survey method for tunnel excavation using the open TBM method

Abstract

The present invention discloses a geological survey method for tunnel excavation using an open TBM method, and relates to the technical field of tunnel and underground engineering geological survey. The survey area on the step is determined, and an on-site survey is conducted to obtain the characteristics of the exposed surrounding rock; the damaged part of the exposed surrounding rock is photographed and recorded and named; as the open TBM is excavated, the area on the step is converted into the area under the step, the survey area under the step is determined, and an on-site survey is conducted to obtain the characteristics of the exposed surrounding rock; a geological sketch is drawn, and the characteristics of the exposed surrounding rock surveyed are recorded in the geological sketch; the damaged part of the exposed surrounding rock is photographed and recorded by video; and a geological distribution map is drawn and archived on a computer according to the geological sketch. The present invention can quickly survey the geological conditions of the excavated tunnel, and systematically count and record the characteristics of the exposed surrounding rock within the survey range, and has the advantages of timely recording and low operation risk.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel and underground engineering geological survey, and in particular to a geological survey method for tunnel excavation using an open TBM method. Background Art

[0002] Various engineering geological problems caused by complex geological conditions pose a great threat to construction safety. Geological surveyors need to timely record the geological conditions of the excavation surface in order to understand the surrounding rock status at the first time and take corresponding support measures. At present, geological surveys of underground caverns such as tunnels often use manual surveys and three-dimensional laser scanning technology. At the construction site of open TBM (full-section tunnel boring machine) tunnel excavation, due to the characteristics of the construction method, the use of three-dimensional laser scanning technology has certain limitations, mainly manifested in: (1) After the cutterhead excavates, it is necessary to promptly support the steel bar row and steel arch frame behind the shield, which will block some surrounding rock damage features; (2) The existence of the open TBM construction platform makes the circular excavation section divided into two parts by the platform, making it impossible to obtain all features at one time; (3) Due to the existence of the straight arm crane and the protective shed, the surrounding rock in some areas will be blocked; (4) In order to meet the conditions of support shoe support, injection molding is required in poor surrounding rock conditions, which will further affect the restoration of the three-dimensional laser scanning results.

[0003] Considering the above problems, in order to obtain the geological information of the open TBM tunnel section as comprehensively as possible, manual survey is still needed. However, the traditional method has the disadvantages of low efficiency and strong subjectivity. Therefore, it is necessary to propose a scientific, objective and standardized geological survey method to meet the geological survey needs of open TBM tunnel excavation. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a geological survey method for open TBM tunnel excavation, which can conduct a comprehensive survey of the geological conditions under open TBM tunnel excavation conditions. The standardized survey process with standardized procedures and strong objectivity can further improve the precision and accuracy of the survey results.

[0005] In order to achieve the above object, the technical solution of the present invention is:

[0006] A geological survey method for excavating a tunnel using an open TBM method comprises the following steps:

[0007] Step 1: Determine the area to be surveyed on the step, and conduct on-site survey on the area to obtain the characteristics of the exposed surrounding rock; the on-site survey includes structural surface survey, strip structure survey and surrounding rock damage survey.

[0008] The on-site survey meets the following requirements: all steel arch frames in the surveyed area are numbered according to their coordinates in the tunnel axial coordinate system, i.e. the farther the coordinates of the steel arch frames are from the origin, the larger the number; the tunnel axial coordinate system takes the tunnel entrance as the origin, the tunnel axial direction as the X-axis, and the coordinates represent the mileage of a certain position from the origin in the axial direction.

[0009] The exposed surrounding rock features obtained by the structural surface survey include: the type of structural surface, the structural surface filling, the number of the steel arch frame sprayed at the location of each structural surface on the entire path from the starting point to the end point of the structural surface, and the spatial orientation of each structural surface; the types of structural surfaces include hard structural surfaces and weak structural surfaces.

[0010] The exposed surrounding rock features obtained from the strip structure survey include: strip structure lithology, strip structure width, the number of the steel arch sprayed at the location of each strip structure on the entire path from the starting point to the end point of the strip structure, and the spatial orientation of each strip structure.

[0011] The exposed surrounding rock features obtained by the surrounding rock failure survey include: the type of surrounding rock failure, the number of the steel arch sprayed at the location of each surrounding rock failure on the entire path from the starting point to the end point of the surrounding rock failure, the spatial orientation of each surrounding rock failure and the depth of the blast pit.

[0012] Step 2: Take photos and record the exposed surrounding rock damage in the area surveyed on this step, obtain the exposed surrounding rock damage image and exposed surrounding rock damage video and name them.

[0013] Step 3: As the open TBM excavates, the area on the step will be converted into the area under the step. The exploration area under the step is determined, and an on-site exploration is conducted on the area under the step to obtain the characteristics of the exposed surrounding rock.

[0014] Step 4: Draw a geological sketch of the survey area under the step, and record the exposed surrounding rock features surveyed in the survey area under the step in the geological sketch.

[0015] The method of recording the exposed surrounding rock features surveyed in the survey area under the steps into the geological sketch map specifically includes: recording the spatial orientation of each structural surface on the entire path from the starting point to the end point of the structural surface and numbering each structural surface in sequence according to the coordinates in the axial coordinate system of the tunnel; recording the spatial orientation of each strip structure on the entire path from the starting point to the end point of the strip structure and numbering each strip structure in sequence according to the coordinates in the axial coordinate system of the tunnel; recording the spatial orientation of each surrounding rock failure on the entire path from the starting point to the end point of the surrounding rock failure and numbering each surrounding rock failure in sequence according to the coordinates in the axial coordinate system of the tunnel.

[0016] Step 5: Take photos and videos of the exposed surrounding rock damage in the survey area under this step, obtain the exposed surrounding rock damage images and exposed surrounding rock damage videos and name them.

[0017] Step 6: Draw and archive the geological distribution map on the computer according to the geological sketch.

[0018] Specifically: import the geological sketch obtained in step 4 into Visio software, use the connecting line command and arbitrary polygon command to draw according to the content in the geological sketch, adjust the line type and scale as required, add scale, legend and annotation content, insert the corresponding exposed surrounding rock damage image, and form a geological distribution map.

[0019] The annotation content includes: the occurrence of each structural surface and the strip structure, the spatial relationship between each structural surface and the tunnel, and the spatial relationship between the strip structure and the tunnel, and the occurrence includes dip and inclination.

[0020] The advantages of the geological survey method for tunnel excavation using an open TBM method of the present invention are:

[0021] 1) Through daily field survey records, the field survey results can be recorded and quantified in real time, and the surrounding rock failure characteristics of the excavation section can be obtained in a timely manner, thus providing a basis for the adjustment of support measures.

[0022] 2) By adopting the dual-area survey method of "on the step" and "under the step", as the open TBM advances, the "on the step" area will be converted into the "under the step" area. By conducting a complete survey process of the "under the step" area, the previous survey records of the "on the step area" can be further improved, and these two sections of survey records with time difference can effectively reflect the short-term damage evolution trend of the surrounding rock of the excavation section.

[0023] 3) By standardizing the survey process, the training threshold for survey technicians is lowered, effectively avoiding differences in geological survey results caused by subjectivity.

[0024] 4) The operation is simple to implement, does not affect normal construction, does not require carrying other equipment, and can be completed independently by one person, which can effectively save manpower and improve efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a flowchart of a geological survey method for excavating a tunnel using an open TBM method according to an embodiment of the present invention.

[0026] Figure 2 It is a schematic diagram of the boundary between the survey area on the step and the area below the step in an embodiment of the present invention.

[0027] Figure 3 It is a schematic diagram of the azimuth of the survey section in an embodiment of the present invention.

[0028] Figure 4It is a schematic diagram of the occurrence marking in the embodiment of the present invention.

[0029] Among them, 1-TBM shield; 2-survey area on the steps; 3-surveyed area on the steps; 4-steps; 5-survey area under the steps; 6-surveyed area under the steps; 7-main control room. DETAILED DESCRIPTION

[0030] A geological survey method for tunnel excavation using an open TBM method, such as Figure 1 As shown, the following steps are included:

[0031] Step 1: Determine the area to be surveyed on the step, and conduct on-site survey on the area to obtain the characteristics of the exposed surrounding rock; the on-site survey includes structural surface survey, strip structure survey and surrounding rock damage survey.

[0032] The on-site survey meets the following requirements: all steel arch frames in the surveyed area are numbered according to their coordinates in the tunnel axial coordinate system, i.e. the farther the coordinates of the steel arch frames are from the origin, the larger the number; the tunnel axial coordinate system takes the tunnel entrance as the origin, the tunnel axial direction as the X-axis, and the coordinates represent the mileage of a certain position from the origin in the axial direction.

[0033] The exposed surrounding rock features obtained by the structural surface survey include: the type of structural surface, the structural surface filling, the number of the steel arch frame sprayed at the location of each structural surface on the entire path from the starting point to the end point of the structural surface, and the spatial orientation of each structural surface; the types of structural surfaces include hard structural surfaces and weak structural surfaces.

[0034] The exposed surrounding rock features obtained from the strip structure survey include: strip structure lithology, strip structure width, the number of the steel arch sprayed at the location of each strip structure on the entire path from the starting point to the end point of the strip structure, and the spatial orientation of each strip structure.

[0035] The exposed surrounding rock features obtained by the surrounding rock failure survey include: the type of surrounding rock failure, the number of the steel arch sprayed at the location of each surrounding rock failure on the entire path from the starting point to the end point of the surrounding rock failure, the spatial orientation of each surrounding rock failure and the depth of the blast pit.

[0036] like Figure 2 As shown, the complete survey area in this embodiment is the area from behind the TBM shield 1 to the front of the main control room 7, including the steps 4, the surveyed areas: the surveyed area 3 on the steps and the surveyed area 6 under the steps, and the unsurveyed areas: the surveyed area 2 on the steps this time and the surveyed area 5 under the steps this time. The surveyed area 2 on the steps this time is the end point of the last survey from behind the TBM shield 1 to the steps in the figure.

[0037] Step 2: Take photos and record the exposed surrounding rock damage in the survey area 2 on this step, obtain the exposed surrounding rock damage image and exposed surrounding rock damage video and name them.

[0038] In this embodiment, three photos are generally required to be taken to record the exposed surrounding rock damage, one of which is a main view of the exposed surrounding rock damage, including the exposed surrounding rock damage and its surrounding environment, the second is a local photo of the exposed surrounding rock damage, and the third is an internal feature map of the damage blast pit; Figure 3 As shown, video recordings were made of the surrounding rocks at 9 o'clock to 11 o'clock, 11 o'clock to 13 o'clock, and 13 o'clock to 15 o'clock in the survey area.

[0039] Step 3: As the open TBM excavates, the area on the step will be converted into the area under the step. The exploration area 5 under the step is determined, and the exploration area 5 under the step is surveyed on site to obtain the characteristics of the exposed surrounding rock.

[0040] like Figure 2 As shown, in this embodiment, the survey area 5 under the step is the end point of the previous survey from the step to the step. With the excavation of the open TBM, the survey area 5 under the step has actually been surveyed during the survey on the step. By carrying out a complete survey process of the subsequent survey area 5 under the step, the survey record of the previous survey area 2 on the step can be further improved.

[0041] Step 4: Draw a geological sketch map of the exploration area 5 under the step, and record the exposed surrounding rock features surveyed in the exploration area 5 under the step in the geological sketch map.

[0042] The method of recording the exposed surrounding rock features surveyed in the survey area under the steps into the geological sketch map specifically includes: recording the spatial orientation of each structural surface on the entire path from the starting point to the end point of the structural surface and numbering each structural surface in sequence according to the coordinates in the axial coordinate system of the tunnel; recording the spatial orientation of each strip structure on the entire path from the starting point to the end point of the strip structure and numbering each strip structure in sequence according to the coordinates in the axial coordinate system of the tunnel; recording the spatial orientation of each surrounding rock failure on the entire path from the starting point to the end point of the surrounding rock failure and numbering each surrounding rock failure in sequence according to the coordinates in the axial coordinate system of the tunnel.

[0043] Step 5: Take photos and videos of the exposed surrounding rock damage in the survey area 5 under the step, obtain the exposed surrounding rock damage image and exposed surrounding rock damage video and name them.

[0044] Step 6: Draw and archive the geological distribution map on the computer according to the geological sketch.

[0045] Specifically: import the geological sketch obtained in step 4 into Visio software, use the connecting line command and arbitrary polygon command to draw according to the content in the geological sketch, adjust the line type and scale as required, add scale, legend and annotation content, insert the corresponding exposed surrounding rock damage image, and form a geological distribution map.

[0046] The marking content is as follows Figure 4 As shown, including: the occurrence of each structural surface and the strip structure, the spatial relationship between each structural surface and the tunnel, and the spatial relationship between the strip structure and the tunnel, the occurrence includes dip and inclination.

Claims

1. A geological survey method for excavating a tunnel using an open TBM method, characterized in that: The steps include: Step 1: Determine the exploration area on the step, and conduct on-site exploration of the exploration area on the step to obtain the characteristics of the exposed surrounding rock; Step 2: Take photos and record the exposed surrounding rock damage in the area surveyed on this step, obtain the exposed surrounding rock damage image and exposed surrounding rock damage video and name them; Step 3: As the open TBM advances, the area on the step will be converted to the area under the step. The exploration area under the step is determined and an on-site exploration is conducted to obtain the exposed surrounding rock characteristics and further improve the exploration records of the previous exploration area on the step. Step 4: Draw a geological sketch of the area under the step, and record the exposed surrounding rock features found in the area under the step in the geological sketch; Step 5: Take photos and videos of the exposed surrounding rock damage in the area under the step survey, obtain the exposed surrounding rock damage image and exposed surrounding rock damage video and name them; Step 6: Draw and archive the geological distribution map on the computer according to the geological sketch; The on-site investigation in step 1 and step 3 includes structural surface investigation, strip structure investigation and surrounding rock damage investigation; The on-site survey in step 1 and step 3 meets the following requirements: All steel arches in the surveyed area are numbered according to their coordinates in the tunnel axial coordinate system, i.e., the farther the coordinates of the steel arches are from the origin, the larger the number; the tunnel axial coordinate system takes the tunnel entrance as the origin, the tunnel axial direction as the X-axis, and the coordinates represent the mileage of a certain position from the origin in the axial direction; The exposed surrounding rock features obtained from the structural surface survey in step 1 and step 3 include: the type of structural surface, the structural surface filling, the number of the steel arch sprayed at the location of each structural surface on the entire path from the starting point to the end point of the structural surface, and the spatial orientation of each structural surface; the types of structural surfaces include hard structural surfaces and weak structural surfaces; The exposed surrounding rock features obtained by the strip structure survey include: strip structure lithology, strip structure width, the number of the steel arch sprayed at the location of each strip structure on the entire path from the starting point to the end point of the strip structure, and the spatial orientation of each strip structure; The exposed surrounding rock features obtained by the surrounding rock failure survey include: the type of surrounding rock failure, the number of the steel arch sprayed at the location of each surrounding rock failure on the entire path from the starting point to the end point of the surrounding rock failure, the spatial orientation of each surrounding rock failure and the depth of the blast pit.

2. A geological survey method for tunnel excavation using an open TBM method according to claim 1, characterized in that: The step 4 of recording the exposed surrounding rock features surveyed in the survey area under the step into the geological sketch map specifically includes: recording the spatial orientation of each structural surface on the entire path from the starting point to the end point of the structural surface and numbering each structural surface in sequence according to the coordinates in the axial coordinate system of the tunnel; recording the spatial orientation of each strip structure on the entire path from the starting point to the end point of the strip structure and numbering each strip structure in sequence according to the coordinates in the axial coordinate system of the tunnel; recording the spatial orientation of each surrounding rock failure on the entire path from the starting point to the end point of the surrounding rock failure and numbering each surrounding rock failure in sequence according to the coordinates in the axial coordinate system of the tunnel.

3. The geological exploration method for excavating a tunnel using an open TBM method according to claim 2, characterized in that: The step five is specifically as follows: importing the geological sketch obtained in step four into Visio software, using the connecting line command and the arbitrary polygon command to draw according to the content in the geological sketch, adjusting the line type and scale as required, adding a scale, legend and annotation content, inserting the corresponding exposed surrounding rock damage image, and forming a geological distribution map.

4. A geological survey method for excavating a tunnel using an open TBM method according to claim 3, characterized in that: The annotation content includes: the occurrence of each structural surface and the strip structure, the spatial relationship between each structural surface and the tunnel, and the spatial relationship between the strip structure and the tunnel, and the occurrence includes dip and inclination.

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