Construction control method for double-hole stacked shield tunnel

Abstract

The present invention provides a construction control method for a double - hole overlapping shield tunnel, which includes obtaining the surface settlement data of the soil mass located above the double - hole overlapping tunnel; obtaining the stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel; and adjusting in real time the construction parameters of the double - hole overlapping tunnel and the reinforcement parameters of the double - hole overlapping tunnel according to the surface settlement data and the stress - strain distribution data of the shield segments. The construction control method for the double - hole overlapping shield tunnel provided by the present invention adjusts and optimizes the construction parameters and the reinforcement parameters in real time according to the actual working conditions of the tunnel soil mass and the shield segments, so as to minimize the ground settlement amount and the tunnel deformation amount as much as possible, reduce the influence on the stratum and surrounding buildings, avoid potential safety hazards, and ensure the safe construction of the double - hole overlapping shield tunnel.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, and particularly to a construction control method for a double - hole overlapping shield tunnel. Background Art

[0002] For double - hole overlapping shield tunnels, especially in the construction of small - spacing overlapping shield tunnels, the mutual influence between the two tunnels is relatively large. Due to different engineering geological conditions and overlapping degrees, the ground settlement caused by construction is also different. Since most subway section construction is carried out in relatively prosperous and densely populated areas of the city, if the ground deformation is greater than the safety threshold, it will have a greater impact on surrounding high - rise buildings, roads, underground pipelines, etc.

[0003] Therefore, how to solve the problem of safe construction of double - hole overlapping shield tunnels has become an important technical problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of the problems existing in the prior art, an embodiment of the present invention provides a construction control method for a double - hole overlapping shield tunnel.

[0005] The present invention provides a construction control method for a double - hole overlapping shield tunnel, including:

[0006] Obtaining ground settlement data of the soil mass above the double - hole overlapping tunnel;

[0007] Obtaining stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel;

[0008] According to the ground settlement data and the stress - strain distribution data of the shield segments, adjusting the construction parameters and reinforcement parameters of the double - hole overlapping tunnel in real time.

[0009] According to a construction control method for a double - hole overlapping shield tunnel provided by the present invention, after obtaining the ground settlement data of the soil mass above the double - hole overlapping tunnel, it further includes:

[0010] Establishing a three - dimensional model of the double - hole overlapping tunnel;

[0011] According to the real - time construction parameters and the three - dimensional model, obtaining a ground settlement regular curve corresponding to the double - hole overlapping tunnel;

[0012] According to the ground settlement regular curve, correcting the ground settlement data.

[0013] According to a construction control method for a double - hole overlapping shield tunnel provided by the present invention, after obtaining the stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel, it further includes:

[0014] Obtain the stress-strain distribution regular curve of the shield segment corresponding to the double-hole overlapping tunnel according to the real-time construction parameters and the three-dimensional model;

[0015] Modify the stress-strain distribution data of the shield segment according to the stress-strain distribution regular curve of the shield segment.

[0016] According to a construction control method for a double-hole overlapping shield tunnel provided by the present invention, the real-time adjustment of the construction parameters and the reinforcement parameters of the double-hole overlapping tunnel according to the ground settlement data and the stress-strain distribution data of the shield segment includes:

[0017] Determine the ground settlement rate of the soil mass located above the double-hole overlapping tunnel according to the corrected ground settlement data;

[0018] When the ground settlement rate is greater than the first safety threshold, and / or, the stress-strain data in the stress-strain distribution data of the shield segment is greater than the second safety threshold, adjust the construction parameters and the reinforcement parameters of the double-hole overlapping tunnel.

[0019] According to a construction control method for a double-hole overlapping shield tunnel provided by the present invention, the obtaining of the ground settlement data of the soil mass located above the double-hole overlapping tunnel includes:

[0020] Arrange a plurality of monitoring points in the soil mass located above the double-hole overlapping tunnel;

[0021] Real-time collect the ground settlement data at the position of each monitoring point.

[0022] According to a construction control method for a double-hole overlapping shield tunnel provided by the present invention, the plurality of monitoring points are divided into multiple groups along the longitudinal direction of the double-hole overlapping tunnel, and each group of monitoring points is distributed along the transverse direction of the double-hole overlapping tunnel.

[0023] According to a construction control method for a double-hole overlapping shield tunnel provided by the present invention, the obtaining of the stress-strain distribution data of the shield segment inside the double-hole overlapping tunnel includes:

[0024] Arrange monitoring elements on the inner side wall of the shield segment, at the splicing position of adjacent shield segments, and at the splicing position of adjacent shield rings to collect the stress-strain data at the position where the monitoring elements are located in real time.

[0025] According to a construction control method for a double-hole overlapping shield tunnel provided by the present invention, the monitoring element is an FBG optical sensor.

[0026] A construction control method for double - hole overlapping shield tunnels provided by the present invention, the construction parameters of the double - hole overlapping tunnels include shield tunneling parameters and shield attitude.

[0027] A construction control method for double - hole overlapping shield tunnels provided by the present invention, the reinforcement parameters of the double - hole overlapping tunnels at least include the prestress of the support trolley, the position of soil grouting, the amount of soil grouting, the setting position of the segment reinforcement bars and the number of segment reinforcement bars.

[0028] In the construction control method for double - hole overlapping shield tunnels provided by the present invention, first obtain the surface settlement data of the soil above the double - hole overlapping tunnels and the stress - strain distribution data of the shield segments, and then adjust the construction parameters of the double - hole overlapping tunnels and the reinforcement parameters of the double - hole overlapping tunnels in real - time according to the surface settlement data and the stress - strain distribution data of the shield segments. With such a setting, during the shield construction of the double - hole overlapping tunnels, according to the actual working conditions of the tunnel soil and the shield segments, the construction parameters and the reinforcement parameters are adjusted and optimized in real - time to minimize the ground settlement and tunnel deformation as much as possible, reduce the impact on the formation and surrounding buildings, avoid potential safety hazards, and ensure the safe construction of the double - hole overlapping shield tunnels. Brief Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 is a top view of the double - hole overlapping shield tunnel;

[0031] Figure 2 is a flow chart of the construction control method for double - hole overlapping shield tunnels provided by the present invention;

[0032] Figure 3 is a schematic diagram of the distribution position of the monitoring points provided by the present invention;

[0033] Figure 4 is a schematic diagram of the distribution position of the monitoring elements on the inner side wall of the shield segment provided by the present invention;

[0034] Figure 5 is a schematic diagram of soil grouting reinforcement provided by the present invention;

[0035] Figure 6 is a schematic diagram of using segment reinforcement bars to reinforce the shield segment provided by the present invention;

[0036] Figure 7It is a schematic diagram of using a support trolley for support and reinforcement provided by the present invention.

[0037] Reference numerals:

[0038] 1: First monitoring section; 2: Second monitoring section; 3: Third monitoring section; 4: Fourth monitoring section; 43: The third monitoring point of the fourth monitoring section; 44: The fourth monitoring point of the fourth monitoring section; 5: Fifth monitoring section; 6: Sixth monitoring section; 7: Shield segment; 71: First monitoring element; 72: Second monitoring element; 73: Third monitoring element; 8: Grouting pipe; 9: Segment reinforcement; 10: Support trolley. Detailed implementation manners

[0039] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] The following Figures 1 to 7 describes the construction control method for a double - hole overlapping shield tunnel according to an embodiment of the present invention.

[0041] Referring to Figures 1 to 4 , an embodiment of the present invention provides a construction control method for a double - hole overlapping shield tunnel, including the following steps:

[0042] Step 110: Obtain the surface settlement data of the soil mass above the double - hole overlapping tunnel.

[0043] Step 120: Obtain the stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel.

[0044] Step 130: According to the surface settlement data and the stress - strain distribution data of the shield segments, adjust the construction parameters and the reinforcement parameters for the double - hole overlapping tunnel in real time.

[0045] During the tunnel construction process, it is inevitable to cause disturbances to the surface, such as surface settlement or uplift. It is necessary to control the disturbance amount to the surface within a safe range to ensure the construction safety and avoid affecting surrounding buildings, etc.

[0046] The ground settlement amount is not only related to tunnel construction and tunnel structure, but also related to the soil structure and geological conditions around the tunnel, and the soil structure and geological conditions around the tunnel vary with different geographical locations. Therefore, for double - hole overlapping tunnels with the same structure, the ground settlement amounts generated during construction at different locations are also different. To ensure the safety of tunnel construction, it is necessary to adjust the construction parameters and reinforcement parameters of the double - hole overlapping tunnel according to the specific working conditions.

[0047] In the embodiment of the present invention, during the shield construction of the double - hole overlapping tunnel, first obtain the ground settlement data of the soil above the double - hole overlapping tunnel and the stress - strain distribution data of the shield segments. Among them, the ground settlement data of the soil above the double - hole overlapping tunnel includes the ground settlement values at different positions of the soil, and the stress - strain distribution data of the shield segments includes the stress - strain data at different positions on the shield segment 7. Then, the operator adjusts and optimizes the construction parameters and reinforcement parameters of the double - hole overlapping tunnel in real - time according to the ground settlement data and the stress - strain distribution data of the shield segments.

[0048] With such a setting, during the shield construction of the double - hole overlapping tunnel, according to the actual working conditions of the tunnel soil and the shield segment 7, the construction parameters and reinforcement parameters are adjusted and optimized in real - time to minimize the ground settlement amount and tunnel deformation amount as much as possible, reduce the impact on the stratum and surrounding buildings, avoid potential safety hazards, and ensure the safe construction of the double - hole overlapping shield tunnel.

[0049] In this embodiment, by combining the ground settlement data and the stress - strain data of the shield segments to jointly guide the construction of the double - hole overlapping shield tunnel, the reason for the deformation of the shield segments can be analyzed more accurately, such as whether it is caused by grouting operation or soil disturbance caused by construction, etc. Thus, the disturbance of the soil during the shield tunneling process can be better grasped. By analyzing the relevant data, a rough judgment is made on the cause of the settlement, and then the corresponding reinforcement measures are selected for timely and accurate reinforcement, reducing the impact, lowering the cost, ensuring construction safety, and improving construction quality.

[0050] In this embodiment, when obtaining the ground settlement data of the soil above the double - hole overlapping tunnel, it is necessary to arrange multiple monitoring points in the soil above the double - hole overlapping tunnel, and then collect the ground settlement data at the position of each monitoring point in real - time.

[0051] The above-mentioned monitoring points can be set in multiple groups, and the multiple groups of monitoring points are distributed along the longitudinal direction of the double-hole stacked tunnel. Each group has multiple monitoring points, and the multiple monitoring points of each group are distributed along the transverse direction of the double-hole stacked tunnel. Specifically, multiple typical dangerous sections of the double-hole stacked tunnel can be determined based on construction experience or engineering analogy or by numerical simulation of the settlement law of the stacked tunnel under working conditions with different spacing and different stacking degrees. Before shield construction, targeted monitoring points are encrypted above each typical dangerous section.

[0052] Specifically, by numerically simulating the settlement law of overlapping tunnels under different spacing and overlapping degrees, it can be seen that the section position where the net spacing between the two tunnels is 1 / 6-1 / 3 of the tunnel diameter is particularly sensitive to the change of the tunnel layout angle, and the section position where the tunnel layout angle is 40-60° has a greater impact on the mutual influence between the double-hole tunnels. During the shield passage stage, the two sides of the tunnel have a lateral displacement away from each other, and the upper and lower parts of the tunnel will have a vertical displacement close to each other, making the entire tunnel tend to be elliptical. Therefore, it is necessary to focus on monitoring and reinforcement of this section.

[0053] It should be noted that the location and number of the above monitoring points should also be considered in combination with geological conditions, stratum properties, construction technology, surface surrounding environment and monitoring costs. The location of the monitoring points should first ensure that the deformation characteristics of the surface are well reflected, and it should be convenient for instrument observation, and it should also try to avoid damage to the monitoring points by external factors.

[0054] The method of setting up monitoring points should be handled flexibly according to the actual situation on site. Standard methods and shallow point setting methods can be used. For areas where cavities are detected in the soil or where collapse may occur during construction, the above monitoring points should be set up using the standard method.

[0055] Specifically, when using the standard method to set up monitoring points, it is first necessary to open a hole with a diameter of 100 mm on the soil surface, and then drive a threaded steel bar with a diameter of 22 mm into the hole. The top of the threaded steel bar is ground into an oval shape, and the length of the threaded steel bar should exceed the depth of the frozen soil line. Specifically, the length of the threaded steel bar can be greater than 0.8 m. It should be noted that if the soil surface is a concrete pavement, the bottom of the threaded steel bar should extend at least 20 cm into the roadbed of the concrete pavement and be separated from the concrete pavement. After that, fill fine sand around the threaded steel bar and tamp it. Here, it is necessary to avoid using concrete or cement to fix the threaded steel bar to prevent the threaded steel bar from settling with the soil surface, which is conducive to ensuring the accuracy of the monitoring results. Finally, an iron cover can be set on the top of each monitoring point for protection.

[0056] For the shallow point - setting method, first use a percussion drill to drill a hole with a depth of about 20 cm and a diameter of 12 cm on the soil surface, and then set a round steel with a diameter of 8 mm and a convex spherical surface inside the hole, and use an anchoring agent to fill the gap.

[0057] The structure and setting method of the above - mentioned monitoring points are relatively simple. On the premise of accurately reflecting the surface deformation characteristics, it can reduce the construction cost.

[0058] After arranging the above - mentioned monitoring points, a surface settlement monitoring device can be used for monitoring, connecting the surface settlement monitoring device to the centralized control platform at the construction site, so as to present the collected surface settlement data on the centralized control platform for the operators to refer to.

[0059] For the monitoring points with a distance less than 20 meters from the tunneling face, they need to be monitored once a day; for the monitoring points with a distance between 20 meters and 50 meters from the tunneling face, they need to be monitored once every two days; for the detection points with a distance greater than 50 meters from the tunneling face, they need to be detected once a week. After determining that the settlement is basically stable according to the data analysis, it is only necessary to detect once a month. If any abnormality occurs during the detection process, the monitoring frequency should be increased. When implementing each on - site monitoring work, on - site safety inspections should be carried out simultaneously, and it is necessary to ensure that the inspections are carried out once a day. In special cases, the inspection frequency should be increased.

[0060] It should be noted that the technology of using the surface settlement monitoring device to monitor the surface settlement data at the positions of each monitoring point is a mature existing technology for those skilled in the art, and will not be elaborated here.

[0061] In a specific embodiment, the left and right lines of a certain urban subway interval tunnel are arranged in a stacked - fall pattern, with the left line above the right line. As the subway runs forward, the distance between the two tunnels of the left and right lines gradually increases, the left line moves downwards and the right line gradually moves upwards, and finally the two tunnels run parallel. Refer to Figure 1 . The main soil layer passed through in the stacked - fall section is the sandy cobble layer, with a buried depth of 21.5 - 23.7 m. The groundwater mainly includes interlayer phreatic water and confined water. The vertical distance of the tunnel in the stacked - fall section is 1.95 - 3.3 m. The left - hand tunnel is located above, and the main soil layer passed through is the silty clay layer. The buried depth of the left - hand tunnel is 13.8 - 15.3 m, and the groundwater mainly includes phreatic water and interlayer phreatic water.

[0062] Six monitoring sections can be designed in the fully overlapping section of the double-hole overlapping tunnel, namely the first monitoring section 1, the second monitoring section 2, the third monitoring section 3, the fourth monitoring section 4, the fifth monitoring section 5, and the sixth monitoring section 6. Among them, the first monitoring section 1 includes four monitoring points, the second monitoring section 2 includes twelve monitoring points, the third monitoring section 3 includes two monitoring points, the fourth monitoring section 4 includes fourteen monitoring points, the fifth monitoring section 5 includes two monitoring points, and the sixth monitoring section 6 includes two monitoring points. The specific distribution is as Figure 3 shown.

[0063] During the shield construction process, monitoring is carried out using the ground settlement monitoring device. The results after the construction of the downward tunnel are as follows:

[0064] The maximum settlement value at the second monitoring section 2 is 5.93 mm, which is slightly smaller than the settlement values at other monitoring sections. After analysis, it is mainly because the second monitoring section 2 is in the shield starting stage, the propulsion speed of the shield machine is slow, and the reinforcement effect of the starting head is good.

[0065] The settlement curves at the first monitoring section 1 and the second monitoring section 2 are asymmetrically distributed along the tunnel center. The maximum settlement of each section occurs on the tunnel center line and gradually decreases laterally along the tunnel. There is a small uplift on the ground surface in the area far from the axis, with an average of less than 2 mm.

[0066] The settlement values of the first monitoring section 1 and the second monitoring section 2 with silty clay overburden are generally smaller than those of the third monitoring section 3 and the fourth monitoring section 4 with sandy pebble stratum overburden. The average settlement values at the first monitoring section 1 and the second monitoring section 2 are about 7 mm, and the average settlement values of the other four monitoring sections are about 12 mm. That is, under the same construction conditions, the ground settlement value with silty clay overburden is slightly smaller than that with sandy pebble layer overburden.

[0067] Under the condition that the soil layers and overburden properties passed through by the third monitoring section 3, the fifth monitoring section 5, and the sixth monitoring section 6 are basically the same, the average settlement values increase in turn, mainly due to the continuous decrease of the tunnel burial depth along the tunnel driving direction.

[0068] The undulations of the third monitoring point 43 and the fourth monitoring point 44 of the fourth monitoring section are relatively large, which do not conform to the ground settlement regular curve. It is predicted that it may be caused by interference factors such as construction or damage of the monitoring points.

[0069] The overall monitoring results show that the maximum settlement value in the overlapping section appears at the fourth monitoring section 4, with a maximum settlement value of 19.08 mm. The settlement amounts of other sections are all less than 15.00 mm, all within the design allowable range.

[0070] During the on-site inspection, all construction parameters were appropriate, the shield attitude was good, and there was no need for major deviation correction. The overall construction of the overlapping section tunnel was in good condition.

[0071] The measured results during the construction of the upward tunnel showed that the advancement of the rear shield in the overlapping section had a trend of first uplift and then settlement on the ground surface. Under the condition that various settlement control measures had good effects, the post-settlement value was not large and was within the safety threshold of ground surface settlement, so there was no need to additionally increase reinforcement measures.

[0072] Through summary and analysis, when the ground surface settlement of the upward tunnel was well controlled, the main reason for the ground surface settlement was the advancement of the downward tunnel; when the ground surface settlement of the upward tunnel was not well controlled, the main reason for the ground surface settlement was the advancement of the upward tunnel.

[0073] Therefore, during the advancement of the rear shield in the overlapping tunnel, measures for controlling ground surface settlement should be strengthened to minimize the secondary disturbance to the ground surface caused by the advancement of the rear shield.

[0074] It should be noted that after obtaining the ground surface settlement data at each monitoring point, those skilled in the art can complete the analysis of the ground surface settlement data according to the technical specifications and common knowledge in the art, and can clarify how to adjust the construction parameters and reinforcement parameters based on the analysis results.

[0075] The shield segment ring is composed of multiple shield segments 7 spliced together. Each shield segment 7 is arc-shaped, and multiple shield segments 7 are connected end to end to form a shield segment ring.

[0076] In this embodiment, when obtaining the stress and strain distribution data of the shield segments inside the double-hole overlapping tunnel, monitoring elements need to be arranged on the inner side wall of the shield segments 7 in the double-hole overlapping tunnel, at the splicing positions of adjacent shield segments 7, and at the splicing positions of adjacent shield segment rings respectively, and the stress and strain data at the positions where the monitoring elements are located are collected in real time by the monitoring elements.

[0077] The layout positions of the monitoring elements are as Figure 4 shown. Among them, the monitoring element arranged on the inner side wall of the shield segment 7 is the first monitoring element 71, the monitoring element arranged at the splicing position of adjacent shield segments 7 is the second monitoring element 72, and the monitoring element arranged at the splicing position of adjacent shield segment rings is the third monitoring element 73.

[0078] It should be noted that Figure 4 is the picture seen by the operator inside the tunnel. Among them, the outer ring is the shield segment ring closest to the operator, and the inner ring is the shield segment ring relatively farther from the operator. The diameters of the two shield segment rings are the same and are set in series, not sleeved together.

[0079] It should be noted that the detection elements arranged at the splicing positions of adjacent shield segments 7 and the detection elements arranged at the splicing positions of adjacent shield segment rings are both arranged on the inner side of the shield segments. That is, the second monitoring element 72 is arranged at the joint position on the inner side of adjacent shield segments 7, and the third monitoring element 73 is arranged at the joint position on the inner side of the shield segment 7 located on adjacent shield segment rings.

[0080] After installing the shield segments 7 at the construction site, install the monitoring elements at the corresponding positions of the shield segments 7, and connect each monitoring element to the centralized control system at the construction site, so as to present the collected stress and strain data on the centralized control platform for the operators to refer to.

[0081] Specifically, the above-mentioned monitoring elements can be FBG optical sensors.

[0082] Use bolts to install and fix each FBG optical sensor by surface mounting. Specifically, one side of the FBG optical sensor has a fixing piece, and the other side is provided with a mounting hole. An expansion bolt can be used to fix the fixing piece on the shield segment 7 to enable better coupling between the FBG optical sensor and the shield segment 7. Connect the bolt through the mounting hole to the shield segment 7. The optical fiber connected to the FBG optical sensor is fixed near the surface of the shield segment 7 to avoid affecting the construction.

[0083] Connect adjacent FBG optical sensors in series and connect them to the centralized control platform at the construction site with an optical cable. During the wiring process of the optical cable, it is necessary to combine the actual working conditions to avoid hanging up the optical cable due to reasons such as personnel and equipment.

[0084] The strain of the FBG optical sensor is the strain at the corresponding position of the shield segment 7. When analyzing and processing the data, make the actual installation position of the FBG optical sensor correspond one-to-one with the wavelength of the light wave reflected by the FBG optical sensor and save it. During the construction process, use a fiber grating demodulator to record the wavelength changes of each FBG optical sensor, and convert the corresponding stress and strain changes according to the wavelength changes.

[0085] In the embodiment of the present invention, after obtaining the surface settlement data of the soil body above the double-hole overlapping tunnel, it further includes:

[0086] Establish a three-dimensional model of the double-hole overlapping tunnel;

[0087] According to the real-time construction parameters and the three-dimensional model, obtain the surface settlement regular curve corresponding to the double-hole overlapping tunnel;

[0088] According to the surface settlement regular curve, correct the surface settlement data.

[0089] Since ground settlement is not only related to the tectonic movement of the soil mass, but also affected by the change in the amount of groundwater resources exploited and external interference factors, when adjusting the construction parameters and reinforcement parameters of the double-hole overlapping tunnel, the above interference factors need to be excluded.

[0090] In this embodiment, according to the structural dimensions such as the double-hole spacing and the overlapping degree of the double-hole overlapping tunnel, a three-dimensional model of the double-hole overlapping tunnel is established, and then numerical simulation software is used to analyze according to the real-time construction parameters to obtain the ground settlement law curve corresponding to the double-hole overlapping tunnel.

[0091] By comparing the above ground settlement data with the ground settlement law curve, if there are individual data in the above ground settlement data that do not conform to the above ground settlement law curve, it indicates that there are interference factors at the position corresponding to the problem data. It is necessary to correct the problem data according to the ground settlement law curve and the ground settlement data at other position points, and then use the corrected ground settlement data as the basis to adjust the construction parameters and reinforcement parameters of the double-hole overlapping tunnel.

[0092] Correspondingly, it is also necessary to correct the stress and strain distribution data of the above shield segments.

[0093] Therefore, in the embodiment of the present invention, after obtaining the stress and strain distribution data of the shield segments inside the double-hole overlapping tunnel, it further includes:

[0094] According to the real-time construction parameters and the three-dimensional model, obtain the stress and strain distribution law curve of the shield segments corresponding to the double-hole overlapping tunnel;

[0095] According to the stress and strain distribution law curve of the shield segments, correct the stress and strain distribution data of the shield segments.

[0096] When using numerical simulation software to analyze the ground settlement value according to the real-time construction parameters, at the same time, analyze the stress and strain of the shield segments to obtain the stress and strain distribution law curve of the shield segments corresponding to the double-hole overlapping tunnel.

[0097] By comparing the above stress and strain distribution data of the shield segments with the stress and strain distribution law curve of the shield segments, if there are individual data in the above stress and strain distribution data of the shield segments that do not conform to the above stress and strain distribution law curve of the shield segments, it indicates that there are interference factors at the position corresponding to the problem data. It is necessary to correct the problem data according to the stress and strain distribution law curve of the shield segments and the stress and strain values of the shield segments at other position points, and then use the corrected stress and strain distribution data of the shield segments as the basis to adjust the construction parameters and reinforcement parameters of the double-hole overlapping tunnel.

[0098] In this embodiment, after the correction of the surface settlement data and the stress-strain distribution data of the shield segments, the construction parameters and reinforcement parameters of the double-hole overlapping tunnel can be adjusted in real time according to the corrected surface settlement data and the corrected stress-strain distribution data of the shield segments.

[0099] Specifically, first, according to the corrected surface settlement data, the surface settlement rate of the soil mass above the double-hole overlapping tunnel is determined. Then, the surface settlement rate and the stress-strain distribution data of the shield segments are respectively compared with the safety thresholds. When the surface settlement rate is greater than the first safety threshold and / or the stress-strain distribution data of the shield segments is greater than the second safety threshold, it is necessary to adjust the construction parameters and reinforcement parameters of the double-hole overlapping tunnel.

[0100] In this embodiment, the above-mentioned construction parameters of the double-hole overlapping tunnel include shield tunneling parameters and shield attitude. Among them, the shield tunneling parameters include shield thrust, propulsion speed, grouting pressure, etc. By determining and optimizing the shield tunneling parameters, overexcavation is avoided, construction continuity is ensured, a good shield attitude is maintained, and deviation is corrected in a timely manner.

[0101] Combined with the above surface settlement data and the stress-strain distribution data of the shield segments, a reference basis can be provided for key reinforcement parts. In order to prevent the surface settlement rate from being greater than the first safety threshold and / or the stress-strain distribution data of the shield segments from being greater than the second safety threshold, during the construction process, certain reinforcement measures are taken, such as using the support trolley 10 for support, soil mass grouting reinforcement, setting segment stiffeners 9, etc. Figures 5 to 7 Schematic diagrams of grouting reinforcement, reinforcement using the segment stiffener 9, and reinforcement of the lower tunnel using the support trolley 10 are respectively shown.

[0102] The above-mentioned reinforcement parameters of the double-hole overlapping tunnel at least include the prestress of the support trolley 10, the soil mass grouting position, the soil mass grouting volume, the setting position of the segment stiffener 9, and the number of the segment stiffeners 9.

[0103] When the surface settlement rate is greater than the first safety threshold and / or the stress-strain distribution data of the shield segments is greater than the second safety threshold, the magnitude of the prestress provided by the support trolley 10 can be increased according to the specific situation, or grouting pipes 8 can be added at relevant positions to increase the soil mass grouting position and grouting volume, or segment stiffeners 9 can be added at corresponding positions or the number of segment stiffeners 9 at this position can be increased.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A construction control method for double-hole overlapping shield tunnels, characterized in that, Including: Obtaining the surface settlement data of the soil mass located above the double - hole overlapping tunnel; Obtaining the stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel; According to the surface settlement data and the stress - strain distribution data of the shield segments, adjusting the construction parameters of the double - hole overlapping tunnel and the reinforcement parameters of the double - hole overlapping tunnel in real time; Wherein, the construction parameters include shield tunneling parameters and shield attitude; the reinforcement parameters at least include the prestress of the support trolley, the soil grouting position, the soil grouting volume, the setting position of the segment stiffeners, and the number of segment stiffeners; After obtaining the surface settlement data of the soil mass located above the double - hole overlapping tunnel, it further includes: Establishing a three - dimensional model of the double - hole overlapping tunnel; According to the real - time construction parameters and the three - dimensional model, obtaining the surface settlement regular curve corresponding to the double - hole overlapping tunnel; According to the surface settlement regular curve, correcting the surface settlement data; After obtaining the stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel, it further includes: According to the real - time construction parameters and the three - dimensional model, obtaining the stress - strain distribution regular curve corresponding to the double - hole overlapping tunnel; According to the stress - strain distribution regular curve of the shield segments, correcting the stress - strain distribution data of the shield segments; The adjusting the construction parameters of the double - hole overlapping tunnel and the reinforcement parameters of the double - hole overlapping tunnel in real time according to the surface settlement data and the stress - strain distribution data of the shield segments includes: According to the corrected surface settlement data, determining the surface settlement rate of the soil mass located above the double - hole overlapping tunnel; When the surface settlement rate is greater than the first safety threshold, and / or, the stress - strain data in the stress - strain distribution data of the shield segments is greater than the second safety threshold, adjusting the construction parameters of the double - hole overlapping tunnel and the reinforcement parameters of the double - hole overlapping tunnel; The obtaining the surface settlement data of the soil mass located above the double - hole overlapping tunnel includes: Arranging a plurality of monitoring points in the soil mass located above the double - hole overlapping tunnel; Real - time collecting the surface settlement data at the position of each monitoring point; The plurality of monitoring points are divided into multiple groups along the longitudinal direction of the double - hole overlapping tunnel, and each group of monitoring points is distributed along the transverse direction of the double - hole overlapping tunnel; Determining multiple typical dangerous sections of the double - hole overlapping tunnel; before shield construction, intensifying the monitoring points targeted above each typical dangerous section; The typical dangerous sections include the section positions where the net distance between the two tunnels is 1 / 6 - 1 / 3 of the tunnel diameter, and the section positions where the layout angle of the tunnel is 40 - 60°; 2. The construction control method for double-hole stacked shield tunnel according to claim 1, wherein The obtaining the stress - strain distribution data of the shield segments inside the double - hole overlapping tunnel includes: Arranging monitoring elements on the inner side wall of the shield segment, at the splicing position of adjacent shield segments, and at the splicing position of adjacent shield segment rings to real - time collect the stress - strain data at the position where the monitoring elements are located; 3. The construction control method for double-hole stacked shield tunnel according to claim 2, wherein The monitoring element is an FBG optical sensor.

Images