Segment longitudinal seam connecting structure suitable for large-diameter shield tunnel and construction method

Abstract

The invention discloses a pipe piece longitudinal joint connecting structure suitable for a large-diameter shield tunnel and a construction method, and relates to the technical field of shield tunnel engineering.The pipe piece longitudinal joint connecting structure comprises a plurality of shield tunnel pipe pieces, and the shield tunnel pipe pieces are connected through longitudinal joint embedded parts; the insertion piece is pre-buried in one shield tunnel segment; the socket component is pre-buried in the other shield tunnel segment; the inserting piece comprises a first connecting part pre-buried in one shield tunnel segment, a plurality of T-shaped parts are arranged on one side of the first connecting part and located in the same vertical direction, and a plurality of first anchoring parts are arranged on the other side of the first connecting part and located in the same horizontal direction; the socket component comprises a second connecting part pre-buried in the other shield tunnel segment, an E-shaped part matched with the T-shaped part is arranged on one side of the second connecting part, and a plurality of second anchoring parts are arranged on the other side of the second connecting part and located in the same horizontal direction. According to the method, high-quality and efficient assembly of the duct pieces can be ensured.

Description

Technical Field

[0001] This invention relates to the field of shield tunnel engineering technology, and more specifically, to a segment longitudinal joint connection structure and construction method suitable for large-diameter shield tunnels. Background Technology

[0002] Traditionally, shield tunnel segment joints primarily use bolt connections. However, bolt connections have several limitations: First, bolt tightening relies heavily on manual operation, resulting in low construction efficiency and poor economics, and human error can make it difficult to guarantee the quality of segment assembly. Second, the presence of bolt manholes weakens the segment cross-sectional strength, making the area around the manholes a stress concentration point, which easily leads to cracking or damage. Finally, bolt connections introduce additional water seepage channels, especially at waterproof joints subjected to internal and external water pressure, easily inducing water leakage problems and affecting the long-term durability and service performance of the tunnel structure.

[0003] The new connector eliminates the drawbacks of traditional bolted connections, employing pre-embedded metal connectors before segment casting to achieve mechanical connection between adjacent segments during construction and assembly. By eliminating traditional handholes and bolt holes, issues such as localized structural weakening and durability problems are effectively avoided. Currently, CT-type joints for longitudinal joints of shield tunnel segments in my country are mostly used in tunnel structures with diameters below 10m. However, large-diameter shield tunnels with diameters exceeding 14m require greater longitudinal joint stiffness, which a single CT joint often cannot meet. Existing technologies use double-layer CT-type joints, CHC joints, or oblique bolt joints for longitudinal joints of large-diameter shield tunnel segments, but these connection methods are complex to construct and difficult to assemble. To solve this problem, there is an urgent need to design a segment longitudinal joint connection structure that meets both stiffness requirements and ease of assembly. Summary of the Invention

[0004] In response to the problems in related technologies, this invention proposes a segment longitudinal joint connection structure and construction method suitable for large-diameter shield tunnels, so as to overcome the above-mentioned technical problems existing in the existing related technologies.

[0005] Therefore, the specific technical solution adopted by the present invention is as follows:

[0006] According to one aspect of the present invention, a segment longitudinal joint connection structure suitable for large-diameter shield tunnels is provided, the structure comprising: a plurality of shield tunnel segments connected to each other by longitudinal joint embedded parts; an insert embedded in the interior of one of the shield tunnel segments; and a support insert embedded in the interior of another shield tunnel segment.

[0007] Preferably, the end face of the shield tunnel segment is provided with several positioning grooves.

[0008] Preferably, the insert includes a first connecting part pre-embedded inside one of the shield tunnel segments, a plurality of T-shaped parts are provided on one side of the first connecting part and in the same vertical direction, and a plurality of first anchoring parts are provided on the other side of the first connecting part and in the same horizontal direction.

[0009] Preferably, the T-shaped part includes several webs disposed on one side of the first connecting part and located in the same vertical direction, and an insertion head is disposed on the other side of the web, and the insertion head is a hollow cylindrical structure.

[0010] Preferably, the support component includes a second connecting part pre-embedded inside another shield tunnel segment, one side of the second connecting part is provided with an E-shaped part that mates with the T-shaped part, and the other side of the second connecting part is provided with a plurality of second anchoring parts in the same horizontal direction.

[0011] Preferably, both the first connecting part and the second connecting part are hollow structures.

[0012] Preferably, the insertion head is provided with a guide slope along its length, and the slope of the guide slope is 1%; the inner wall of the E-shaped part is provided with a limiting groove that cooperates with the guide slope.

[0013] According to another aspect of the present invention, a construction method for a segment longitudinal joint connection structure suitable for large-diameter shield tunnels is also provided, the method comprising:

[0014] S1. Use a segment assembly machine to insert the insert into the positioning groove on the end face of the shield tunnel segment;

[0015] S2. Use the segment assembly machine to adjust the position of adjacent shield tunnel segments, so that the insert slides along the positioning groove towards the bearing insert until the T-shaped part contacts the E-shaped part;

[0016] S3. Analyze the optimal adjustment parameters of the insert using a genetic algorithm, generate control commands based on the optimal adjustment parameters, and drive the segment assembly machine to adjust the horizontal and vertical angles of the insert so that the guide slope is aligned with the inclined surface of the inner wall of the limiting groove. At this time, the enlarged end of the insert head matches the opening of the limiting groove.

[0017] S4. Start the shield tunnel hydraulic cylinder jack and apply the jacking force to push the T-shaped part to the bottom of the E-shaped part until the guide slope is completely in contact with the inner wall of the limiting groove, so that the longitudinal joint of the adjacent shield tunnel segments is connected.

[0018] Preferably, the optimal adjustment parameters of the insert are analyzed using a genetic algorithm, including:

[0019] Obtain the adjustment parameters during the assembly of shield tunnel segments, set the engineering constraint boundary, and construct several combinations of adjustment parameters within the engineering constraint boundary; generate an initial population, and use each individual in the initial population as each combination of adjustment parameters;

[0020] A coordinate system is constructed based on the horizontal coordinate axis, vertical coordinate axis, and axial coordinate axis of the shield tunnel cross section. The flatness of the shield tunnel segments, the gap between the segments joints, the misalignment of the segments, and the assembly time of the segments are calculated by combining the preset corner coordinates on the end face of the shield tunnel segments.

[0021] The flatness of the tunnel segments, the gap between the tunnel segments, the misalignment of the tunnel segments, and the assembly time of the tunnel segments are used as independent variables, and a fitness function is constructed by combining them with predefined weight coefficients.

[0022] A tournament selection method is used to randomly select several individuals from the initial population to compete. The fitness of each individual is calculated using a fitness function. The individual with the highest fitness is selected as the winner to generate a new population. The fitness calculation process is repeated until a new population is selected.

[0023] After each iteration, a preset number of the best individuals are selected and retained in the new population to replace the worst-performing individuals in the new population. The iteration stops when the iteration conditions are met, and the optimal solution is output as the optimal adjustment parameter.

[0024] Preferably, activating the shield tunneling hydraulic jack and applying a jacking force to push the T-shaped part into the bottom of the E-shaped part until the guide slope is completely in contact with the inner wall of the limiting groove includes:

[0025] The shield tunneling hydraulic cylinder jacks are activated, and the T-shaped section is pushed at a constant speed by the shield tunneling hydraulic cylinder jacks. During the pushing process, the relationship between the jack thrust and the preset threshold is monitored in real time.

[0026] When the jack thrust is less than the preset threshold, the T-section continues to be pushed at a constant speed by the shield cylinder jack; when the jack thrust is greater than or equal to the preset threshold, the shield cylinder jack stops pushing.

[0027] During the uniform jacking of the shield tunneling machine, the force and displacement deviations of the shield tunneling machine hydraulic cylinder jacks are iteratively detected and corrected until the guide slope and the inner wall of the limiting groove are completely in contact.

[0028] The beneficial effects of this invention are as follows:

[0029] 1. This invention inserts the T-shaped insert head into the limiting groove of the E-shaped part. The insertion head is restricted in displacement by the inner wall of the limiting groove, thereby forming a stable connection between the insert and the bearing, and thus enabling the two shield tunnel segments to be assembled. A guide slope is set on the surface of the insert head, which is pressed against the slope in the limiting groove during the assembly process to form a certain pre-tightening force. At the same time, a genetic algorithm is used to finely control the micro-adjustment operation of the assembly machine during the segment assembly process, thereby ensuring high-quality and efficient segment assembly.

[0030] 2. Compared with the single-layer CT-type longitudinal seam connection structure, the present invention can provide greater structural rigidity; compared with the double-layer CT-type longitudinal seam connection structure, the present invention is easier to assemble; compared with the traditional manual adjustment of the segment assembly method, the present invention has higher assembly quality and efficiency. Overall, the present invention is of high quality and high efficiency and has strong scalability. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of an insert in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the insert at another angle in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention;

[0035] Figure 4 This is a schematic diagram of the slope of an insert in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0036] Figure 5 This is a schematic diagram of the bearing component in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0037] Figure 6 This is a schematic diagram of the bearing component at another angle in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0038] Figure 7 This is a schematic diagram of the bearing component at another angle in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0039] Figure 8 This is one of the three-dimensional assembly drawings of inserts in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention;

[0040] Figure 9This is the second three-dimensional assembly drawing of inserts in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0041] Figure 10 This is the third three-dimensional assembly drawing of inserts in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention;

[0042] Figure 11 This is the fourth three-dimensional assembly drawing of inserts in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0043] Figure 12 This is a schematic diagram of the structure of a shield tunnel segment in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0044] Figure 13 This is a detailed view of a shield tunnel segment in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0045] Figure 14 This is a schematic diagram of shield tunnel segments before assembly in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0046] Figure 15 This is a schematic diagram of shield tunnel segments during fine-tuning alignment in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0047] Figure 16 This is a schematic diagram of a shield tunnel segment when inserting a reserved hole in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0048] Figure 17 This is a schematic diagram of shield tunnel segments during sliding assembly in a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0049] Figure 18 This is a flowchart of a genetic algorithm in a construction method for a segment longitudinal joint connection structure applicable to a large-diameter shield tunnel according to an embodiment of the present invention;

[0050] Figure 19 This is a flowchart of fine-tuning operations in a construction method for a segment longitudinal joint connection structure applicable to a large-diameter shield tunnel according to an embodiment of the present invention.

[0051] Figure 20 This is a flowchart of the jacking operation in a construction method for a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to an embodiment of the present invention.

[0052] In the picture:

[0053] 1. Shield tunnel segment; 101. Positioning groove; 2. Insert; 201. First connecting part; 202. T-shaped part; 2021. Web plate; 2022. Insert head; 20221. Guide slope; 203. First anchoring part; 3. Supporting part; 301. Second connecting part; 302. E-shaped part; 3021. Limiting groove; 303. Second anchoring part. Detailed Implementation

[0054] To further illustrate the various embodiments, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. These drawings are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these drawings, those skilled in the art should be able to understand other possible implementation methods and the advantages of the present invention. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0055] According to an embodiment of the present invention, a segment longitudinal joint connection structure and construction method suitable for large-diameter shield tunnels are provided.

[0056] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments, such as... Figures 1-17 As shown, according to an embodiment of the present invention, a segment longitudinal joint connection structure suitable for large-diameter shield tunnels includes: a plurality of shield tunnel segments 1, which are connected to each other by longitudinal joint embedded parts; an insert 2, which is embedded in the interior of one of the shield tunnel segments 1; and a support insert 3, which is embedded in the interior of another shield tunnel segment 1. The end face of the shield tunnel segment 1 is provided with a plurality of positioning grooves 101 (the positioning grooves 101 are provided in front of the embedded support insert 3 of the shield tunnel segment 1).

[0057] The insert 2 includes a first connecting part 201 pre-embedded inside one of the shield tunnel segments 1. Several T-shaped parts 202 are provided on one side of the first connecting part 201 and in the same vertical direction, and several first anchoring parts 203 are provided on the other side of the first connecting part 201 and in the same horizontal direction.

[0058] Specifically, the first anchoring part 203 is connected to the first connecting part 201 and is embedded in the shield tunnel segment 1, and the T-shaped part 202 extends out of the shield tunnel segment 1. There are two shield tunnel segments 1, two first anchoring parts 203 and two T-shaped parts 202.

[0059] Specifically, the first connecting part 201 and the two T-shaped parts 202 are cast as a single piece, all made of cast iron or cast steel.

[0060] The T-shaped part 202 includes a plurality of webs 2021 disposed on one side of the first connecting part 201 and located in the same vertical direction, and an insertion head 2022 disposed on the other side of the webs, wherein the insertion head 2022 is a hollow cylindrical structure.

[0061] The support plug 3 includes a second connecting part 301 pre-embedded inside another shield tunnel segment 1. One side of the second connecting part 301 is provided with an E-shaped part 302 that cooperates with the T-shaped part 202. On the other side of the second connecting part 301 and in the same horizontal direction, a plurality of second anchoring parts 303 are provided.

[0062] Specifically, the second connecting part 301 and the E-type part 302 are cast as a whole, both made of cast iron or cast steel. The second anchoring part 303 is connected to the second connecting part 301 and is embedded inside the shield tunnel segment 1.

[0063] The first connecting part 201 and the second connecting part 301 are both hollow structures, and the first anchoring part 203 and the second anchoring part are both ribbed steel bars with a length greater than 35 times the diameter of the steel bar.

[0064] The insertion head 2022 is provided with a guide slope 20221 along its length, and the slope of the guide slope 20221 is 1%; the inner wall of the E-shaped part 302 is provided with a limiting groove 3021 that cooperates with the guide slope 20221.

[0065] Specifically, the two ends of the insert head 2022 are of different sizes, and the guide slope 20221 and the limiting groove 3021 have the same inclination angle, fitting together after assembly. The inclination angle α is determined based on the height h of the small end section of the insert head 2022, h = (0.85-0.9)H, where H is the height of the large end section of the insert head 2022; the formula for calculating the inclination angle is: α = arctan[(Hh) / 2l], where l is the length of the insert head 2022.

[0066] The following section provides further explanation of the positioning channel design, limiting and guiding design, material and structural optimization, and anchoring reinforcement design in this invention.

[0067] 1. Positioning channel design: A positioning channel 101 is set longitudinally along the shield tunnel segment 1 in front of the end face of the pre-embedded support 3 to guide the sliding of the T-shaped part 202 of the insert 2. The width of the positioning channel 101 is adapted to the width of the web 2021 of the T-shaped part 202 to ensure accurate guidance during the assembly process.

[0068] 2. Limiting and guiding design: The inner wall of the limiting groove 3021 of the E-type part 302 is provided with an inclined surface, which matches the guide inclined surface 20221 at the end of the insertion head 2022 of the T-type part 202. The inclined slope of the guide inclined surface 20221 is 1%. During assembly, the pre-tightening force is generated through the contact of the inclined surface, which enhances the connection stability.

[0069] 3. Material and structural optimization: The first connecting part 201 and T-shaped part 202 of the insert 2 and the second connecting part 301 and E-shaped part 302 of the support plug 3 are all integrally cast from cast iron or cast steel to ensure the integrity of the structure and shear strength; the first connecting part 201, the second connecting part 301 and the insert head 2022 are designed as hollow structures to reduce the self-weight of the components without affecting the strength and rigidity of the insert 2 and the support plug 3.

[0070] 4. Anchorage reinforcement design: The anchorage parts of insert 2 and bearing insert 3 are all ribbed steel bars with a length greater than 35 times the diameter (for example, using Φ25 steel bars with a length ≥875mm), which are pre-embedded in the concrete of shield tunnel segment 1 to ensure that the anchorage force meets the load requirements of large-diameter tunnels.

[0071] According to another embodiment of the present invention, a construction method for a segment longitudinal joint connection structure suitable for large-diameter shield tunnels is also provided, the method comprising:

[0072] S1. Use the segment assembly machine to insert the insert 2 into the positioning groove 101 on the end face of the shield tunnel segment 1;

[0073] S2. Use the segment assembly machine to adjust the position of the adjacent shield tunnel segment 1, so that the insert 2 slides along the positioning groove 101 towards the bearing insert 3 until the T-shaped part 202 contacts the E-shaped part 302.

[0074] S3. Analyze the optimal adjustment parameters of the insert 2 using a genetic algorithm, generate control commands based on the optimal adjustment parameters, and drive the segment assembly machine to adjust the horizontal and vertical angles of the insert 2 so that the guide slope 20221 is aligned with the inclined surface of the inner wall of the limiting groove 3021. At this time, the enlarged end of the insert head 2022 matches the opening of the limiting groove 3021.

[0075] S4. Start the shield cylinder jack and apply the jacking force to push the T-shaped part 202 to the bottom of the E-shaped part 302 until the guide slope 20221 is completely in contact with the inner wall of the limiting groove 3021 so that the longitudinal joint of the adjacent shield tunnel segment 1 is connected.

[0076] The optimal adjustment parameters for insert 2, analyzed using a genetic algorithm, include:

[0077] Obtain the adjustment parameters during the assembly of shield tunnel segment 1, set the engineering constraint boundary, and construct several combinations of adjustment parameters within the engineering constraint boundary; generate an initial population, and use each individual in the initial population as each combination of adjustment parameters;

[0078] A coordinate system is constructed based on the horizontal coordinate axis, vertical coordinate axis, and axial coordinate axis of the shield tunnel cross section. The flatness of the shield tunnel segment 1, the gap between the segment joints, the misalignment of the segment, and the assembly time of the segment are calculated by combining the preset corner point coordinates on the end face of the shield tunnel segment 1.

[0079] The flatness of the tunnel segments, the gap between the tunnel segments, the misalignment of the tunnel segments, and the assembly time of the tunnel segments are used as independent variables, and a fitness function is constructed by combining them with predefined weight coefficients.

[0080] A tournament selection method is used to randomly select several individuals from the initial population to compete. The fitness of each individual is calculated using a fitness function. The individual with the highest fitness is selected as the winner to generate a new population. The fitness calculation process is repeated until a new population is selected.

[0081] After each iteration, a preset number of the best individuals are selected and retained in the new population to replace the worst-performing individuals in the new population. The iteration stops when the iteration conditions are met, and the optimal solution is output as the optimal adjustment parameter.

[0082] The process of activating the shield tunneling hydraulic jacks and applying a jacking force to push the T-shaped part 202 into the bottom of the E-shaped part 302 until the guide slope 20221 is completely in contact with the inner wall of the limiting groove 3021 includes:

[0083] The shield tunneling hydraulic cylinder jacks are activated, and the T-shaped section 202 is pushed at a constant speed by the shield tunneling hydraulic cylinder jacks. During the pushing process, the relationship between the jack thrust and the preset threshold is detected in real time.

[0084] When the jack thrust is less than the preset threshold, the T-section 202 is pushed at a constant speed by the shield cylinder jack; when the jack thrust is greater than or equal to the preset threshold, the shield cylinder jack is stopped.

[0085] During the uniform jacking of the shield tunneling hydraulic cylinder jack, the force deviation and displacement deviation of the shield tunneling hydraulic cylinder jack are iteratively detected and corrected until the guide inclined surface 20221 and the inner wall of the limiting groove 3021 are completely in contact.

[0086] The construction method of the segment longitudinal joint connection structure applicable to large-diameter shield tunnels in this invention will be further described below.

[0087] Step 1: Initial positioning of the insert:

[0088] When assembling shield tunnel segment 1, the segment assembly machine is operated to align the two T-shaped parts 202 of the insert 2 with the positioning groove 101 on the end face of the shield tunnel segment 1, and insert it along the positioning groove 101, so that the insertion head 2022 of the T-shaped part 202 extends into the positioning groove 101.

[0089] Step 2, Sliding Guide and Docking:

[0090] By adjusting the position of adjacent shield tunnel segments 1 using the segment assembly machine, the T-shaped part 202 of the insert 2 slides along the positioning groove 101 toward the bearing 3 until the insertion head 2022 of the T-shaped part 202 contacts the entrance of the E-shaped part 302 of the bearing 3.

[0091] Step 3: Fine-tuning and alignment of the limiting groove:

[0092] Using the fine-tuning function of the segment assembly machine, the horizontal and vertical angles of the insert 2 are adjusted so that the guide slope 20221 of the T-shaped part 202 is aligned with the inclined surface of the inner wall of the limiting groove 3021 of the E-shaped part 302. At this time, the enlarged end of the insert head 2022 matches the opening of the limiting groove 3021.

[0093] like Figure 18 As shown, the fine-tuning function of the segment assembly machine obtains optimal parameters through a genetic algorithm, specifically including:

[0094] 1. Problem definition and parameter mapping:

[0095] The key adjustment parameters affecting assembly quality are determined as follows: three-dimensional translation (δx, δy, δz), three-dimensional rotation angle (θx, θy, θz), and translation speed (v).

[0096] 2. Gene coding design:

[0097] The parameter combinations are represented as chromosomes using real number encoding. Each chromosome contains 7 gene loci, corresponding to 7 regulatory parameters. Engineering constraints are set as follows: the 3D translation is within ±20mm, the 3D rotation angle is within ±5°, and the translation speed is within 0.5-3mm / s.

[0098] 3. Population initialization:

[0099] An initial population is generated to ensure that the parameter space is uniformly covered. Each individual represents a set of random parameter combinations. The minimum unit of the three-dimensional translation is 0.5 mm, the minimum unit of the three-dimensional rotation angle is 0.5°, and the minimum unit of the translation speed is 0.5 mm / s. Thus, there are a total of 9600 parameter combinations for the population.

[0100] 4. Fitness function design:

[0101] Using segment flatness a1, segment joint gap a2, segment misalignment a3, and assembly time t as independent variables, and w1, w2, w3, and w4 as weighting coefficients, a fitness function F(a1,a2,a3,t) is established. The smaller F is, the higher the fitness, i.e., the higher the positioning efficiency. The fitness function expression is:

[0102] F=a1·w1+a2·w2+a3·w3+t·w4;

[0103] In this design, x represents the horizontal coordinate axis of the shield tunnel cross-section, y represents the numerical coordinate axis, and z represents the axial coordinate axis. Points on the design axis are the centers of the tunnel cross-section. Assuming the coordinates of a point o on the axis are (x0, y0, z0), and the coordinates of a corner point i1 on the end face of the tunnel segment are (x0, y0, z0),... i1 ,y i1 ,z i1 ), the other three corner points i2(x) on the end face of the tube segment i2 ,y i2 ,z i2 i3(x) i3 ,y i3 ,z i3 i4(x) i4 ,y i4 ,z i4 If the flatness is ), then the flatness is

[0104] a1=|z0-z i1 |+|z0-z i2 |+|z0-z i3 |+|z0-z i4 |;

[0105] The smaller the value of a1, the smoother the end face of the tube segment.

[0106] Assume the coordinates (x) of the corner point p1 of the adjacent segment that is adjacent to corner point i1. p1 ,y p1 ,z p1 If ), then the joint gap is:

[0107] a2=[(x i1 -x p1 ) 2 +(y i1 -y p1 ) 2 +(z i1 -z p1 ) 2 ] 0.5 ;

[0108] According to the design specification "Code for Construction and Acceptance of Shield Tunnel" GB50446-2017, a2≤2mm. The smaller a2 is, the better the segment assembly quality.

[0109] Based on the above assumptions, the misalignment between adjacent tunnel segments is:

[0110] a3=|[(x i1 -x0) 2 +(y i1 -y0) 2 +(z i1 -z0) 2 ] 0.5 -[(x p1 -x0) 2 +(y p1 -y0) 2 +(z p1 -z0) 2 ] 0.5 |;

[0111] Among them, the smaller a3 is, the smaller the segment misalignment.

[0112] It should be noted that t is the segment assembly time, which is related to the translation speed v1 and the rotation speed v2. Based on the maximum three-dimensional translation amount of ±20mm and the maximum rotation angle of ±5°, the movement time t can be expressed as:

[0113] t = Δl / v1 + Δγ / v2;

[0114] In the formula, Δl is the translation distance and Δγ is the rotation angle. The faster the translation and rotation speeds, the shorter the assembly time.

[0115] 5. Implementation of genetic operators:

[0116] The tournament selection method is adopted, which utilizes a small-scale competition mechanism: each time, 10 individuals are randomly selected from the population to "compete". The two individuals with the highest fitness win and are selected. This process is repeated until the new generation of population is full. The new generation of population continues the above selection process, which not only retains excellent individuals, but also maintains population diversity.

[0117] 6. Elite Retention Strategy:

[0118] At the end of each generation, the top 20% of the best individuals are selected and directly retained into the next generation to replace the worst-performing individuals in the new population, ensuring that the optimal solutions discovered are not lost during the evolutionary process.

[0119] 7. Termination condition determination:

[0120] Optimization can be stopped when the fitness improvement is less than 0.1% for 10 consecutive generations.

[0121] Hardware integration:

[0122] 1. Establish a real-time verification system: The genetic algorithm is directly connected to the control system, and data on segment end face flatness, segment joints, segment misalignment, and assembly time are collected in real time during the assembly process. The optimization results can be directly transmitted to the control terminal, as detailed below. Figure 19 As shown.

[0123] 2. Dynamic adjustment of weighting coefficients:

[0124] Table 1: Dynamic Adjustment Table of Weighting Coefficients

[0125]

[0126] As shown in Table 1, the weight coefficients are automatically updated based on the assembly data of the previous ring segment. The total change in weight is as follows:

[0127] Δw=(a1-1) / a1+(a2-0.5) / a2+(a3-0.5) / a3+(a4-40) / a4;

[0128] Among them, w1', w2', w3', and w4' are the weighting coefficients for the flatness of the segment ring surface, the segment joint gap, the segment misalignment, and the assembly time during the assembly of the previous ring segment, respectively.

[0129] Step 4: Push and lock to complete the connection:

[0130] The shield tunneling hydraulic jacks are activated, applying a jacking force to push the T-shaped part 202 of the insert 2 completely into the bottom of the limiting groove 3021 of the E-shaped part 302, until the guide slope 20221 is tightly fitted with the inner wall of the limiting groove 3021. During the jacking process, the enlarged end of the T-shaped part 202 is constrained by the closed end of the limiting groove 3021, forming multi-directional constraints of tensile, shear, and bending resistance, ultimately achieving the longitudinal joint fixation of the two shield tunnel segments 1.

[0131] Specifically, such as Figure 20 As shown, the segment jacking assembly process is as follows:

[0132] ① Initial jacking: Each standard segment is controlled by three hydraulic jacks. The jacks jack the segment at a constant speed of 1 mm / s. During the process, the jack thrust F and the frictional force threshold f of the connecting parts are monitored in real time. u (f u =μ·G N μ is the coefficient of friction between the connecting parts, G N The relationship between the components of the force (in the normal direction of the segment end face):

[0133] When F < 0.8f u At this time, it can be determined that the tunnel segment is in a normal assembly state, and the jack continues to advance at a constant speed;

[0134] When F≥0.8f uWhen the tunnel segments are in close contact, the jack stops advancing and checks whether the advancing distance has reached the designed assembly position. If the designed assembly position is reached, the displacement deviation ΔS = 0 (the difference between the current position and the target position), and the assembly is complete; if the designed assembly position is not reached, ΔS ≠ 0, and fine-tuning is required.

[0135] ② Jack fine-tuning: Based on the measured force deviation of the three jacks, ΔF = F - 0.8f u Dynamic adjustment of displacement deviation ΔS (difference between current position and target position):

[0136] When ΔF > 0 and ΔS < 0 for one jack and ΔF < 0 for the other two jacks, the jacking displacement of the other two jacks is increased simultaneously.

[0137] When ΔF < 0 for one jack, ΔF > 0 for the other two jacks and ΔS < 0, the control segment retracts slightly in the reverse direction.

[0138] ③ Iterative progress until completion: After each fine-tuning, the force and displacement of the jacks are re-detected, and the "progress-pause-fine-tuning" process is repeated until the segment assembly is completed.

[0139] This invention is applicable to large-diameter shield tunnel projects (diameter ≥ 10m) such as subways, highways, and railways, and is especially suitable for segment assembly under complex geological conditions such as high water pressure and soft soil, and has broad prospects for promotion.

[0140] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A segment longitudinal joint connection structure suitable for large-diameter shield tunnels, characterized in that, The structure includes: A plurality of shield tunnel segments (1), and the shield tunnel segments (1) are connected to each other by longitudinal joint embedded parts; Insert (2) is pre-embedded inside one of the shield tunnel segments (1); The support insert (3) is pre-embedded inside another shield tunnel segment (1).

2. The segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 1, characterized in that, The end face of the shield tunnel segment (1) is provided with several positioning channels (101).

3. The segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 2, characterized in that, The insert (2) includes a first connecting part (201) pre-embedded inside one of the shield tunnel segments (1), a plurality of T-shaped parts (202) are provided on one side of the first connecting part (201) and in the same vertical direction, and a plurality of first anchoring parts (203) are provided on the other side of the first connecting part (201) and in the same horizontal direction.

4. The segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 3, characterized in that, The T-shaped part (202) includes a plurality of webs (2021) disposed on one side of the first connecting part (201) and located in the same vertical direction. An insertion head (2022) is disposed on the other side of the webs, and the insertion head (2022) is a hollow cylindrical structure.

5. A segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 4, characterized in that, The support component (3) includes a second connecting part (301) pre-embedded inside another shield tunnel segment (1). On one side of the second connecting part (301) is an E-shaped part (302) that cooperates with the T-shaped part (202). On the other side of the second connecting part (301) and in the same horizontal direction, a plurality of second anchoring parts (303) are provided.

6. A segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 5, characterized in that, Both the first connecting part (201) and the second connecting part (301) are hollow structures.

7. A segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 6, characterized in that, The insertion head (2022) is provided with a guide slope (20221) along its length, and the slope of the guide slope (20221) is 1%. The inner wall of the E-shaped part (302) is provided with a limiting groove (3021) that cooperates with the guide slope (20221).

8. A construction method for a segment longitudinal joint connection structure suitable for large-diameter shield tunnels, used to assemble the segment longitudinal joint connection structure for large-diameter shield tunnels as described in claim 7, characterized in that, The method includes: S1. Using a segment assembly machine, insert the insert (2) into the positioning groove (101) on the end face of the shield tunnel segment (1); S2. Use the segment assembly machine to adjust the position of the adjacent shield tunnel segments (1), so that the insert (2) slides along the positioning groove (101) toward the bearing (3) until the T-shaped part (202) contacts the E-shaped part (302); S3. Analyze the optimal adjustment parameters of the insert (2) using a genetic algorithm, generate control commands based on the optimal adjustment parameters, and drive the segment assembly machine to adjust the horizontal and vertical angles of the insert (2) so that the guide slope (20221) is aligned with the inclined surface of the inner wall of the limiting groove (3021). At this time, the enlarged end of the insert head (2022) matches the opening of the limiting groove (3021). S4. Start the shield cylinder jack and apply the jacking force to push the T-shaped part (202) to the bottom of the E-shaped part (302) until the guide slope (20221) is completely in contact with the inner wall of the limiting groove (3021) so that the longitudinal joints of the adjacent shield tunnel segments (1) are connected.

9. A construction method for a segment longitudinal joint connection structure suitable for large-diameter shield tunnels according to claim 8, characterized in that, The analysis of the optimal adjustment parameters of the insert (2) using a genetic algorithm includes: Obtain the adjustment parameters during the assembly of the shield tunnel segment (1), set the engineering constraint boundary, and construct several adjustment parameter combinations within the engineering constraint boundary; generate an initial population, and use each individual in the initial population as each adjustment parameter combination; A coordinate system is constructed based on the horizontal coordinate axis, vertical coordinate axis, and axial coordinate axis of the shield tunnel cross section. The flatness of the shield tunnel segment (1), the joint gap of the segment, the misalignment of the segment, and the assembly time of the segment are calculated by combining the preset corner coordinates on the end face of the shield tunnel segment (1). The flatness of the tunnel segments, the gap between the tunnel segments, the misalignment of the tunnel segments, and the assembly time of the tunnel segments are used as independent variables, and a fitness function is constructed by combining them with predefined weight coefficients. A tournament selection method is used to randomly select several individuals from the initial population to compete. The fitness of each individual is calculated using a fitness function. The individual with the highest fitness is selected as the winner to generate a new population. The fitness calculation process is repeated until a new population is selected. After each iteration, a preset number of the best individuals are selected and retained in the new population to replace the worst-performing individuals in the new population. The iteration stops when the iteration conditions are met, and the optimal solution is output as the optimal adjustment parameter.

10. A construction method for a segment longitudinal joint connection structure applicable to large-diameter shield tunnels according to claim 9, characterized in that, The activation of the shield tunneling hydraulic cylinder jack, applying a jacking force to push the T-shaped part (202) into the bottom of the E-shaped part (302) until the guide slope (20221) is completely in contact with the inner wall of the limiting groove (3021) includes: Start the shield tunnel hydraulic cylinder jacks and push the T-shaped section (202) at a constant speed through the shield tunnel hydraulic cylinder jacks. During the pushing process, the relationship between the jack thrust and the preset threshold is detected in real time. When the jack thrust is less than the preset threshold, the T-shaped section (202) is pushed at a constant speed by the shield cylinder jack; when the jack thrust is greater than or equal to the preset threshold, the shield cylinder jack is stopped from advancing. During the uniform jacking of the shield tunneling hydraulic cylinder jack, the force deviation and displacement deviation of the shield tunneling hydraulic cylinder jack are iteratively detected and corrected until the guide inclined surface (20221) and the inner wall of the limiting groove (3021) are completely in contact.

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