Method for selecting a sling for hanging a shield machine assembly

Abstract

The application discloses a sling selection method for shield machine hoisting assembly, aiming to solve the problems of great difficulty in selecting the sling for shield machine hoisting and great security risks caused by improper selection. The method can effectively identify the security risk points of the sling used in the shield machine hoisting assembly process and the factors that should be considered in the selection of the sling, and the dynamic load coefficient and the uneven load coefficient are taken into account when the main hoist and the auxiliary hoist are selected, so that the selection of the main hoist and the auxiliary hoist can meet the uneven load distribution and the additional load when the main hoist and the auxiliary hoist cooperate to hoist the cutter head. Under the premise of reasonable selection, the hoisting safety can be ensured, and the hoist overturning can be avoided. Through the calculation of the maximum hoisting weight of the sling and the maximum equivalent stress of the sling lug weld and the static load monitoring, the stress of the sling and the sling lug can be ensured to be reliable, and the fracture of the sling or the sling lug weld that causes the shield body to fall and be damaged can be avoided. Overall, all kinds of security risks existing in the sling during the shield hoisting process are eliminated.

Description

Technical Field

[0001] This application relates to the field of tunnel boring machine (TBM) launching technology, specifically to a method for selecting lifting slings for TBM hoisting and assembly. Background Technology

[0002] A tunnel boring machine (TBM) is a large and complex tunneling machine integrating multiple systems such as electricity, pneumatics, and hydraulics. It mainly consists of two parts: the shield body and the supporting equipment. The shield body structure includes the cutterhead, shield, drive unit, segment assembly machine, and soil removal mechanism. The supporting equipment typically consists of a connecting bridge and several trailers. The connecting bridge serves as a transitional connection between the shield body and the corresponding supporting trailers; during tunneling, the shield body drives the connecting bridge and the supporting trailers forward. The supporting equipment is equipped with electrical control systems, hydraulic systems, grouting systems, bentonite systems, foam systems, compressed air systems, circulating water systems, lubrication systems, excavated soil and segment conveying systems, and grease seals, providing various forms of support for the tunneling of the main structure at the front end of the TBM.

[0003] Because tunnel boring machines (TBMs) contain numerous system components, their overall size and weight are enormous, making it impossible to transport, lift, and lower them into the shaft as a single unit. Therefore, after production, the TBM must be disassembled and transported to the construction site. Each component is then sequentially hoisted into the TBM's launching shaft and assembled into a complete machine. Only after commissioning can excavation begin. During this hoisting process, lifting lugs at each component are secured with slings, and a crawler crane is used for lifting. Due to the large number of TBM components, their varying shapes and sizes, and the significant weight of individual components, selecting the right lifting slings is challenging. Improper selection can lead to hazards such as crane overturning or sling breakage, affecting the integrity of the TBM and the safety of construction personnel.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the background technology of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] In view of at least one of the above technical problems, this disclosure provides a method for selecting lifting slings for shield machine hoisting assembly, aiming to solve the problem that the selection of lifting slings for shield machine hoisting is difficult and that improper selection can cause great safety hazards.

[0006] According to one aspect of this disclosure, a method for selecting lifting slings for shield tunneling machine hoisting assembly is provided, comprising the following steps:

[0007] (1) Based on the maximum weight of the shield tunneling components to be lifted and the weight of the hook running rope Calculate the load of the main crane Where K1 is the dynamic load coefficient;

[0008] (2) Calculate the working radius of the crane based on the crane length L, the distance D from the crane to the edge of the working well, the width H of the capping beam at the well opening, the radius S of the center of gravity of the lifting point, and the reserved length C inside the well. ;

[0009] (3) Based on the crane working radius R0 corresponding to the largest integer closest to R, consult the crane performance table to determine the rated lifting weight F corresponding to the working radius R0 of the crane;

[0010] (4) Determine whether the rated lifting capacity F is satisfied. Based on this, the main crane is selected;

[0011] (5) Based on the weight M of the cutterhead of the tunnel boring machine to be lifted and the weight of the hook running rope. Calculate the load of the auxiliary crane Where K1 is the dynamic load factor and K2 is the unbalanced load factor;

[0012] (6) Repeat steps (2)-(4) to determine whether the rated lifting weight F meets the requirements. Based on this, the auxiliary crane is selected;

[0013] (7) Calculation of rigging stress, based on the maximum weight of the shield tunneling components to be lifted. Given the number of lifting points N, the total number of slings M between each lifting point and the corresponding crane hook, and the allowable tensile force P of each sling, determine the maximum lifting weight of the slings. Does it meet the requirements? ;

[0014] (8) Calculate the force on each lifting lug, and establish a spatial rectangular coordinate system for the lifting lug with the center of the lifting lug hole as the origin, and with the direction perpendicular to the lifting lug connecting plate and the direction parallel to the axis of the lifting lug connecting plate as the two coordinate axes, and the direction perpendicular to the two coordinate axes as the Z direction.

[0015] (9) Based on the angle θ between the lug connecting plate and the horizontal direction, and the force on the lug in the horizontal direction. The lifting lug is subjected to force in the vertical direction. Forces perpendicular to these two directions Calculate the component of force perpendicular to the direction of the lifting lug connecting plate. Component of force parallel to the axis of the lifting lug connecting plate ;

[0016] (10) Calculate the maximum equivalent stress of the lifting lug weld. Where A is the weld area; based on the allowable stress of the lifting lug material. Calculate the allowable stress of the weld. Determine if the condition is met. ;

[0017] (11) Confirm the maximum lifting capacity of the rigging. Maximum equivalent stress of lifting lug weld After meeting the corresponding requirements, a static load test lift is performed. After the corresponding crane is connected to the corresponding component, the component is lifted 100-200mm off the ground and left to stand still for 10-15 minutes. During this period, the distance between the component and the ground is monitored. If the distance remains unchanged, the lifting slings are appropriate.

[0018] In some embodiments of this disclosure, in step (1) or step (5), the dynamic load coefficient K1 ranges from 1.1 to 1.3.

[0019] In some embodiments of this disclosure, in step (5), the value of the unbalanced load coefficient K2 ranges from 1.1 to 1.3.

[0020] In some embodiments of this disclosure, in step (7), the allowable tensile force ,in, The minimum breaking tensile force of the rigging; K is the safety factor, which ranges from 7 to 9;

[0021] In some embodiments of this disclosure, in step (7), the rigging is made of steel wire rope, with a corresponding minimum breaking tensile force. ,in, d is the conversion factor for the minimum breaking tensile force of a steel wire rope with a certain structure, and its value ranges from 0.295 to 0.33; d is the nominal diameter of the steel wire rope (in mm). This refers to the nominal tensile strength of the steel wire.

[0022] In some embodiments of this disclosure, in step (9), the vertical force on the lifting lugs after the lifting weight is evenly distributed at each lifting point is calculated based on the force balance. The forces acting on the lifting points are decomposed based on the angles between the rigging and the horizontal plane, and between the rigging and the line connecting the rigging to the same-side lifting lugs, thus obtaining the horizontal forces acting on the lifting lugs. Forces perpendicular to the horizontal and vertical directions of the lifting lugs, respectively. .

[0023] The one or more technical solutions provided in this application embodiment have at least the following technical effects or advantages: They effectively identify the safety risk points of the lifting slings used in the shield machine hoisting and assembly process and the factors that must be considered when selecting lifting slings. For example, when selecting the main crane and auxiliary crane, dynamic load coefficient and uneven load coefficient should be taken into account, so that the selection of the main and auxiliary cranes can meet the uneven load distribution and additional load when the main and auxiliary cranes cooperate to lift the cutterhead. Under the premise of reasonable selection, the lifting safety can be ensured and the crane overturning can be avoided. Moreover, through the calculation of the maximum lifting weight of the slings and the maximum equivalent stress of the lifting lug weld and static load monitoring, the stress reliability of the slings and lifting lugs can be guaranteed, and the breakage of the slings or lifting lug welds can be avoided, which would cause the shield to fall and break. Overall, various safety hazards in terms of lifting slings during the shield hoisting process are eliminated. Attached Figure Description

[0024] Figure 1 This is a schematic diagram illustrating the process of the main and auxiliary cranes lifting the cutterhead in one embodiment of this application.

[0025] Figure 2 This is a side view of the lifting of the three sections at the bottom of the shield tail in one embodiment of this application.

[0026] Figure 3 This is a top view of the lifting of the three sections at the bottom of the shield tail in one embodiment of this application.

[0027] Figure 4 This is a schematic diagram of the force analysis of the lifting lug in one embodiment of this application.

[0028] In the above diagrams, 1 is the main crane, 2 is the auxiliary crane, 3 is the cutterhead, 4 is the lifting lug, 5 is the lifting point, and 6 is the wire rope. Detailed Implementation

[0029] Unless otherwise specified, the components, equipment, etc. involved in the following embodiments are all commercially available products.

[0030] To better understand the technical solution of this application, the above technical solution will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] This example discloses a method for selecting lifting slings for the hoisting assembly of a tunnel boring machine (TBM). The TBM is a 1068 slurry-balanced TBM with a digging diameter of 13.32m, a total length of approximately 135m, a main unit weight of approximately 2027T, and a rear-mounted trailer weight of approximately 1119T. The heaviest single component is the cutterhead, weighing 461T (including the cutterhead). The rear-mounted trailer consists of trailers #1 to #5, two connecting bridge sections, and an auxiliary platform. Because this TBM is a large-diameter machine with significant individual component weight, the hoisting and assembly process is complex, time-consuming, and carries high safety risks. To meet the overall hoisting and assembly requirements and ensure safe and timely completion of the assembly work, the main hoisting and assembly face is divided into two sections: the main unit hoisting assembly shaft and the rear-mounted trailer hoisting assembly shaft. A connecting tunnel is excavated between the two shafts, and main and auxiliary cranes are installed at each shaft for hoisting and assembly operations, thereby shortening the assembly period. To ensure lifting safety and prevent crane overturning or sling breakage, it is necessary to select and calculate the appropriate slings and rigging. This includes the following steps:

[0032] (1) Based on the maximum weight of the shield tunneling components to be lifted and the weight of the hook running rope Calculate the load of the main crane Where K1 is the dynamic load coefficient.

[0033] The first step is to select the appropriate crane. To prevent the crane from tipping over due to unbalanced loads, the crane's load capacity and working radius are the primary considerations. Because the components of the tunnel boring machine are large in size and weight, a direct connection between the component to be lifted and the crane hook is not possible; a hook-and-rope connection is required. Therefore, the weight of the hook-and-rope must be considered when calculating the crane load. Furthermore, since the weights of the various components of the tunnel boring machine (TBM) vary, the maximum weight of the component to be lifted is selected. The crane load is taken into account; considering that the movement of the crane during the lifting of heavy objects will have a certain impact on the crane load, thus increasing the crane load; accordingly, the crane load is calculated. K1 is the dynamic load factor, with a value range of 1.1-1.3, which is used to reflect the process load applied to the crane during the lifting process. Through this dynamic load factor, the adverse effects of the process load on the crane's bearing capacity are eliminated.

[0034] In this embodiment, the heaviest component of the tunnel boring machine is the cutterhead, which weighs approximately 461 tons. Measurements show the hook rope weighs 10 tons. Considering the process load, a dynamic load factor of 1.2 is used to calculate the crane load. .

[0035] (2) Calculate the working radius of the crane based on the crane length L, the distance D from the crane to the edge of the working well, the width H of the capping beam at the well opening, the radius S of the center of gravity of the lifting point, and the reserved length C inside the well. .

[0036] In this example, the main crane and auxiliary crane are located in non-connected tunnel areas on either side of the main and auxiliary shaft openings. Since the cranes lift shield tunneling components from the side, and the components rotate around the vertical axis at the crane's center before being lowered into the shaft, the center of the crane is considered the stress point. The most stringent scenario is that the crane is positioned on the tunnel axis with its long side parallel to the tunnel axis; therefore, half the crane length L is included in the crane's working radius. Furthermore, since the crane operates near the corresponding shaft opening at a certain distance, the crane's working radius must include the distance D between the crane and the edge of the working shaft. For the stability of the working shaft, a capping beam is installed at the shaft opening to reinforce the shaft wall. This capping beam has a certain width, and when the crane lowers components into the shaft, it must be placed on both sides of the capping beam. The crane's working radius includes the width H of the capping beam at the wellhead. During lifting, force balance is considered to avoid uneven stress on the components during the lifting process. The lifting point is often located at the center of gravity of the component; therefore, the crane's working radius includes the radius S of the component's center of gravity. Furthermore, for the main crane, the cutterhead and each shield body need to be lowered from the main wellhead. Since the cutterhead and shield body are connected front and rear, the lifting point above the wellhead differs when the cutterhead and shield body are lowered. Specifically, in this embodiment, the shield body is lifted and lowered first, followed by the cutterhead. Because the main crane is located on one side of the starting tunnel entrance, a space needs to be reserved inside the well for the cutterhead, i.e., a certain distance needs to be left between the capping beam and the shield body end face. This distance needs to take into account the working radius of the crane. For the cutterhead, the reserved length C inside the well is 0.

[0037] In this example, when installing the cutterhead at the main shaft opening, the crawler crane has a width of 10m and a length L of 12m. The crane is 0.2m from the shaft opening D during operation, the cap beam width H is 2.5m, and the cutterhead position reserve C is 0m. Since the cutterhead needs to be lowered vertically during installation, the two lifting lugs are positioned at the cutterhead cutting ring. Therefore, the radius C of the lifting point (i.e., the distance from the lifting lug at the cutting ring to the front face of the cutterhead) is 1m. Based on this, the working radius of the crane during cutterhead installation is calculated. When lowering the shield into the well, the shield needs to be lowered horizontally. Therefore, the lifting point is set on the vertical line passing through the center of gravity of the shield. Thus, the radius C of the center of gravity of the corresponding lifting point when the shield is lowered into the well is the distance between the lifting point and the lifting lug.

[0038] (3) Based on the crane working radius R0 corresponding to the largest integer closest to R, consult the crane performance table to determine the rated lifting weight F corresponding to the working radius R0 of the crane.

[0039] Based on the above calculations, the working radius of the crane when the cutterhead is lowered into the well is R=9.7m. The working radius of the crane corresponding to the largest integer closest to this is 10m. In this example, a QUY650 650T crawler crane is selected as the main crane. According to the performance table of this crane, its rated lifting capacity F=650T corresponds to a working radius of 10m.

[0040] (4) Determine whether the rated lifting capacity F is satisfied. Based on this, the main crane is selected.

[0041] Based on the calculation results of steps (1) to (3), by comparison, it is found that when the cutterhead is lifted, the corresponding rated lifting weight F is greater than the crane load. (F=650T>F1=565.2T), which satisfies Therefore, it is safe and reasonable to select the QUY650 650T crawler crane as the main crane, in accordance with the requirements.

[0042] (5) Based on the weight M of the cutterhead of the tunnel boring machine to be lifted and the weight of the hook running rope. Calculate the load of the auxiliary crane Where K1 is the dynamic load factor and K2 is the unbalanced load factor.

[0043] Because of the large diameter of the cutterhead, it is laid flat at the construction site. Therefore, when lowering the cutterhead into the well, it needs to be turned over from the ground to an upright position before the operation. Furthermore, due to the heavy weight of the cutterhead and the welding work required, several support piers need to be installed below it. This means that the turning and lowering of the cutterhead cannot be completed by the main crane alone; therefore, the auxiliary crane is needed to assist in the turning operation. Considering that the mutual movement between the lifting machinery may generate additional loads acting on the lifting machinery, the heavy object, and the slings, or that the lifting load cannot be completely and evenly distributed between the two cranes due to the asynchronous operation between the main and auxiliary cranes, the unbalanced load factor is used to account for the impact of this unbalanced phenomenon in the lifting calculations in this example. Therefore, based on the weight M of the cutterhead and the weight of the hook rope... See Figure 1 Considering that the main crane and the auxiliary crane lift the cutterhead simultaneously, calculate the load on the auxiliary crane. Where K1 is the dynamic load factor, used to reflect the influence of moving loads, and its value ranges from 1.1 to 1.3; in this example, it is taken as 1.2. K2 is the unbalanced load factor, used to reflect loads with uneven force distribution, and its value ranges from 1.1 to 1.3; in this example, it is taken as 1.2. The auxiliary crane load is calculated from this. .

[0044] (6) Repeat steps (2)-(4) to determine whether the rated lifting weight F meets the requirements. Based on this, the selection of the auxiliary crane is carried out. If it meets the requirements... If so, then the selection of the auxiliary crane is reasonable and safe.

[0045] (7) Calculation of rigging stress, based on the maximum weight of the shield tunneling components to be lifted. Given the number of lifting points N, the total number of slings M between each lifting point and the corresponding crane hook, and the allowable tensile force P of each sling, determine the maximum lifting weight of the slings. Does it meet the requirements? .

[0046] Because the components to be lifted by the tunnel boring machine (TBM) are large, they cannot be directly connected to the crane hook for lifting operations. Therefore, appropriate rigging is required between each lifting lug and the hook of each component. In this embodiment, steel wire ropes are used as rigging. Before lifting, the stress calculation of the steel wire ropes needs to be performed to avoid the steel wire ropes breaking due to insufficient load-bearing capacity, which could cause the component to fall. In this example, the heaviest component of the TBM to be lifted, the cutterhead, is selected as the calculation standard. Adding the weight of the hook rope connected to it during lifting, the total weight is... Furthermore, there are eight lifting points around the cutterhead, two of which are main lifting points connected to the main crane, two are turning lifting points connected to the auxiliary crane, and the other four are translation lifting points. However, since the cutterhead is vertically lifted by the main crane after the auxiliary crane assists in turning, only the rigging at the two main lifting points bears the force after the cutterhead is vertical, so the number of lifting points N=2. Then, the maximum lifting weight of the rigging is calculated based on the number M of rigging between each lifting point and the corresponding crane hook, and the allowable tensile force P of each rigging. In this example, when lifting the cutterhead, three steel wire ropes are installed between each lifting point and the hook, i.e., M=3, where the allowable tensile force is... ,in, The minimum breaking strength of the rigging is given by _____; K is the safety factor, which ranges from 7 to 9, and in this example, it is specifically set to 8. Furthermore, steel wire rope is used as the rigging, and its corresponding minimum breaking strength is given by _____. ,in, The conversion factor is the minimum breaking tensile force of a steel wire rope with a certain structure. The value ranges from 0.295 to 0.33. In this example, the value is 0.3. d is the nominal diameter of the steel wire rope (in mm). This refers to the nominal tensile strength of the steel wire; in this example, the φ120mm steel wire rope has a nominal tensile strength of 1670. Then its corresponding minimum breaking tensile force This allows us to obtain the allowable tensile force of the wire rope sling. Based on the weight of the cutter head plus the weight of the hook and rope. ,judge Therefore, the selected rigging meets the usage requirements, and the selection of rigging is reasonable and safe.

[0047] (8) Calculate the force on each lifting lug, and establish a spatial rectangular coordinate system for the lifting lug with the center of the lifting lug hole as the origin, and with the direction perpendicular to the lifting lug connecting plate and the direction parallel to the axis of the lifting lug connecting plate as the two coordinate axes, and the direction perpendicular to the two coordinate axes as the Z direction.

[0048] In this embodiment, see Figures 2-3 The tunnel boring machine (TBM) has four lifting points each for the front shield, middle shield, tail shield, and main drive, and eight lifting points for the cutterhead. Each lifting point is a lifting lug welded to a corresponding TBM component. Therefore, the welding strength of the lifting lugs directly affects the lifting safety of the TBM components. Thus, it is necessary to calculate the stress on the lifting lugs to ensure that the allowable stress of the welding materials meets the requirements and to ensure lifting safety. In this example, see... Figures 2-3 After the three bottom sections of the shield tail are connected, they are lifted together. Since each shield section has four lifting points, the upper surface of the three bottom sections of the shield tail has a total of eight lifting points. In this example, in order to balance the force on the lifting lugs to the greatest extent and avoid the lifting lugs bearing excessive vertical tension, the lifting lugs on the outside of the shield section are selected, so that the angle between the rigging is increased and the vertical component of the force at the lifting lugs is reduced.

[0049] Since the lifting lug is connected to the component through the lifting lug seat on its base, in order to reflect the reliability of the connection, a rectangular coordinate system is established with the center of the lifting lug hole as the origin, and the directions perpendicular to the lifting lug connecting plate and parallel to the axis of the lifting lug connecting plate as two coordinate axes, with the direction perpendicular to these two coordinate axes as the Z direction. Thus, the normal stress and shear stress at the lifting lug connection can be calculated by the force components perpendicular to the direction of the lifting lug connecting plate and parallel to the axis of the lifting lug connecting plate.

[0050] (9) Based on the angle θ between the lug connecting plate and the horizontal direction, and the force on the lug in the horizontal direction. The lifting lug is subjected to force in the vertical direction. Forces perpendicular to these two directions Calculate the component of force perpendicular to the direction of the lifting lug connecting plate. Component of force parallel to the axis of the lifting lug connecting plate .

[0051] First, determine the total force at each lug. Based on the position of the hook lifting point and the weight of the component, determine the vertical tension distributed to each lug. In this example, the main hook lifting point passes through the vertical line where the component's center of gravity is located. Due to the internal structure of each section at the bottom of the shield tail, the weights at the front and rear are inconsistent. Therefore, when lifting along the vertical line where the center of gravity is located, the force on each lifting lug is uneven. In this example, the force on each of the three front lifting lugs at the bottom of the shield tail is 105.5T, and the force on each of the rear lifting lugs is 98.6T. Taking the front lifting lugs with greater force as an example, this force is the vertical force on the lifting lug. See Figure 4Taking the center of the lifting lug hole as the origin, the force along the wire rope direction is calculated based on the angle between the lifting lug wire rope and the horizontal plane, as well as the component of the force along the wire rope projected onto the horizontal plane. Then, based on the angle between the projection line of the wire rope onto the horizontal plane and the line connecting the lifting lug to two adjacent lifting lugs, the force of the component projected onto the horizontal plane of the force along the wire rope direction is decomposed to obtain the horizontal force on the lifting lug. Forces perpendicular to the horizontal and vertical directions of the lifting lugs, respectively. After trigonometric function operations, in this example, the corresponding... Corresponding .

[0052] because The direction of the connecting plate of the lifting lug differs from the direction of the axis by a certain angle. The direction is also the same angle different from the direction perpendicular to the lifting lug connecting plate. The direction of the lifting lug is the same as the Z-direction of the rectangular coordinate system established in step (8). Therefore, based on the angle θ between the lifting lug connecting plate and the horizontal direction, the component force perpendicular to the lifting lug connecting plate can be calculated. Component of force parallel to the axis of the lifting lug connecting plate .

[0053] (10) Calculate the maximum equivalent stress of the lifting lug weld. Where A is the weld area; based on the allowable stress of the lifting lug material. Calculate the allowable stress of the weld. Determine if the condition is met. .

[0054] In this example, the weld area A is taken as 46400, so the maximum equivalent stress of the lifting lug weld is calculated accordingly. In this example, the lifting lugs use butt welds, and the material is Q345B, whose allowable stress is... The corresponding allowable stress of the weld is... ,satisfy This means that the ear plate weld meets the requirements.

[0055] (11) Confirm the maximum lifting capacity of the rigging. Maximum equivalent stress of lifting lug weld After meeting the corresponding requirements, a static load test lift is performed. After the corresponding crane is connected to the corresponding component, the component is lifted 100-200mm off the ground and left to stand still for 10-15 minutes. During this period, the distance between the component and the ground is monitored. If the distance remains unchanged, the lifting slings are appropriate.

[0056] When the maximum lifting capacity of the rigging satisfy Maximum equivalent stress of lifting lug weld satisfy Afterwards, a static load test was carried out. The selected main crane and auxiliary crane were used to lift the heavy components. In this example, the bottom of the component was 100mm off the ground and remained stationary for 10 minutes. The distance between the bottom of the component and the ground was observed. If there was any change, the steps (1)-(10) were reviewed, the selection steps of each lifting sling were checked, and the selection and calculation were carried out again.

[0057] Although some preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0058] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the inventive spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for selecting lifting slings for shield tunneling machine assembly, characterized in that, Includes the following steps: (1) Based on the maximum weight of the shield tunneling components to be lifted M max and the weight of the hook running rope M 0 Calculate the load of the main crane F1 = K1 × (M) max +M0), where K1 is the dynamic load coefficient; (2) Based on the crane length L, the distance D from the crane to the edge of the working well, the width H of the capping beam at the well opening, the radius S of the center of gravity of the lifting point, and the reserved length C in the well, calculate the working radius R of the crane: R = L / 2 + D + H + S + C; (3) Based on the crane working radius R0 corresponding to the largest integer closest to R, consult the crane performance table to determine the rated lifting weight F corresponding to the working radius R0 of the crane; (4) Determine whether the rated lifting capacity F satisfies F>F1, and select the main crane accordingly; (5) Based on the weight M of the cutterhead of the tunnel boring machine to be lifted and the weight of the hook running rope. M 0 Calculate the load of the auxiliary crane Where K1 is the dynamic load factor and K2 is the unbalanced load factor; (6) Repeat steps (2)-(4) to determine whether the rated lifting weight F satisfies F>F2, and select the auxiliary crane accordingly; (7) Calculation of rigging stress, based on the maximum weight M of the shield tunneling components to be lifted. max 1. Number of lifting points N, total number of slings M between each lifting point and the corresponding crane hook, and allowable tensile force P of each sling. Determine the maximum lifting weight M of the slings. m Does =N×M×P satisfy M? m >M max ; (8) Calculate the force on each lifting lug, and establish a spatial rectangular coordinate system for the lifting lug with the center of the lifting lug hole as the origin, and with the direction perpendicular to the lifting lug connecting plate and the direction parallel to the axis of the lifting lug connecting plate as the two coordinate axes, and the direction perpendicular to the two coordinate axes as the Z direction. (9) Based on the angle θ between the connecting plate of the lifting lug and the horizontal direction, and the horizontal force F on the lifting lug... x The vertical force F on the lifting lug y Forces F perpendicular to these two directions respectively z Calculate the component of force perpendicular to the direction of the lifting lug connecting plate. F n =F y cosθ-F x sinθ Component of force parallel to the axis of the lifting lug connecting plate F t =F y sinθ+F x cosθ ; (10) Calculate the maximum equivalent stress of the lifting lug weld. Where A is the weld area; calculate the allowable stress of the weld based on the allowable stress σ of the lifting lug material. σ w =0.8σ Determine if the condition is met. σ n <σ w ; (11) Confirm the maximum lifting capacity M of the rigging m Maximum equivalent stress of lifting lug weld σ n After meeting the corresponding requirements, a static load test lift is performed. After the corresponding crane is connected to the corresponding component, the component is lifted 100-200mm off the ground and left to stand still for 10-15 minutes. During this period, the distance between the component and the ground is monitored. If the distance remains unchanged, the lifting slings are appropriate.

2. The method for selecting lifting slings for shield machine hoisting and assembly according to claim 1, characterized in that, In step (1) or step (5), the dynamic load coefficient K1 ranges from 1.1 to 1.

3.

3. The method for selecting lifting slings for shield machine hoisting and assembly according to claim 1, characterized in that, In step (5), the value range of the unbalanced load coefficient K2 is 1.1-1.

3.

4. The method for selecting lifting slings for shield machine hoisting and assembly according to claim 1, characterized in that, In step (7), the allowable tensile force ,in, F min The minimum breaking tensile force of the rigging is denoted by K; K is the safety factor, which ranges from 7 to 9.

5. The method for selecting lifting slings for shield machine hoisting and assembly according to claim 4, characterized in that, In step (7), the rigging is made of steel wire rope, with a corresponding minimum breaking tensile force. ,in, μ is a conversion factor for the minimum breaking tensile force of a steel wire rope with a certain structure, with a value range of 0.295-0.33; d is the nominal diameter of the steel wire rope in mm; φ This refers to the nominal tensile strength of the steel wire.

6. The method for selecting lifting slings for shield machine hoisting and assembly according to claim 4, characterized in that, In step (9), the vertical force on the lifting lugs after the lifting weight is evenly distributed at each lifting point is calculated based on the force balance. F y The forces acting on the lifting points are decomposed based on the angle between the rigging and the horizontal plane, and the angle between the projection of the rigging onto the horizontal plane and the line connecting the lifting lugs on the same side. The forces acting on the lifting lugs in the horizontal direction are then obtained. F x Forces perpendicular to the horizontal and vertical directions of the lifting lugs, respectively. F z .

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