Prestressed immersed tube segment, design method and SPMT-based barge loading method

Abstract

The present invention relates to a prestressed immersed tube segment, a design method and an SPMT-based barge loading method. In the prestressed immersed tube segment, transverse first prestressed steel strands are provided in a bottom plate of the prestressed immersed tube segment, such that all parts of the bottom plate can satisfy support conditions of SPMTs, and then the SPMTs can be fully distributed under the bottom plate, sufficient support force can be provided when using the SPMTs to transport the prestressed immersed tube segment and the degree of cracking of the prestressed immersed tube segment can be reduced, and therefore the SPMTs can be used to transport immersed tube segments into barges; transverse second prestressed steel strands are provided in a top plate, the second prestressed steel strands can overcome the impact of the first prestressed steel strands on the stress of the top plate, and the arrangement of the first prestressed steel strands and the second prestressed steel strands conforms to the load forms of the bottom plate and the top plate of the immersed tube segment during operation, satisfying the stress state of the immersed tube segment during operation, reducing the amount of reinforcement of the bottom plate and the top plate, and saving costs.

Description

Prestressed immersed tube joint, design method and SPMT vehicle on-raft method TECHNICAL FIELD

[0001] The present application relates to the technical field of immersed tube on-raft, in particular to a prestressed immersed tube joint, a design method and an SPMT vehicle on-raft method. BACKGROUND

[0002] In the prior art, for a reinforced concrete immersed tube joint, when moving on-raft from a wharf to a semi-submersible raft, a row of transport trolleys needs to be arranged below the side walls and the middle wall of the immersed tube joint, but the support height of the transport trolleys has a small adjustment stroke and poor self-adaptive ability, which is not conducive to crack control during the on-raft process. Compared with the transport trolleys, the SPMT vehicle has a large stroke self-adaptive adjustment capability and walking flexibility, and can reduce the crack control difficulty of the immersed tube joint during the floating state on-raft process.

[0003] However, the use of the SPMT vehicle will face new technical problems:

[0004] The SPMT vehicle has small carrying capacity and large size, and the immersed tube joint has large weight, so a large number of SPMT vehicle groups are needed, and full paving under the immersed tube joint is basically required. However, the existing immersed tube joint is only designed based on operation requirements, and has a small supportable area, which can only support the bottom plate corresponding to the region of the middle wall and the side wall, and cannot support the bottom plate corresponding to the region between the middle wall and the side wall. Paving the SPMT vehicle group on the bottom plate corresponding to the region of the middle wall and the side wall makes the SPMT vehicle group unable to meet the carrying condition, and thus the SPMT vehicle cannot be used for on-raft transportation of the immersed tube joint. SUMMARY

[0005] The present application aims to overcome the deficiencies in the prior art that the reinforced concrete immersed tube joint can only pave the SPMT vehicle group on the bottom plate corresponding to the region of the middle wall and the side wall of the immersed tube joint, which cannot meet the carrying condition, and thus the SPMT vehicle cannot be used for on-raft transportation of the immersed tube joint, and provides a prestressed immersed tube joint, a design method and an SPMT vehicle on-raft method.

[0006] In a first aspect, the present application provides a prestressed immersed tube joint, comprising a top plate, a bottom plate, a first side wall, a first middle wall, a second middle wall and a second side wall, the first side wall, the first middle wall, the second middle wall and the second side wall being arranged in a lateral sequence along the immersed tube joint, and comprising a first prestressed steel bundle and a second prestressed steel bundle;

[0007] The first prestressed steel bundle is arranged in the bottom plate, the first prestressed steel bundle is arranged in a lateral direction of the bottom plate, and the first prestressed steel bundle is distributed in a longitudinal direction of the bottom plate;

[0008] The first prestressed steel bundle includes a first passing point, a second passing point, a third passing point, a fourth passing point and a fifth passing point, the first passing point is located below the first side wall, the second passing point is located between the first side wall and the first middle wall, the third passing point is located between the first middle wall and the second middle wall, the fourth passing point is located between the second middle wall and the second side wall, and the fifth passing point is located below the second side wall, the first prestressed steel bundle is arranged in a wave shape in the vertical direction, the first passing point, the third passing point and the fifth passing point are wave troughs, and the second passing point and the fourth passing point are wave crests;

[0009] The second prestressed steel bundle is arranged in the top plate, is arranged transversely along the top plate, and is distributed longitudinally along the top plate;

[0010] The second prestressed steel bundle includes a sixth passing point, a seventh passing point, an eighth passing point, a ninth passing point and a tenth passing point, the sixth passing point is located above the first side wall, the seventh passing point is located between the first side wall and the first middle wall, the eighth passing point is located between the first middle wall and the second middle wall, the ninth passing point is located between the second middle wall and the second side wall, and the tenth passing point is located above the second side wall, the second prestressed steel bundle is arranged in a wave shape in the vertical direction, the sixth passing point, the eighth passing point and the tenth passing point are located at wave crests, and the seventh passing point and the ninth passing point are located at wave troughs.

[0011] The first prestressed steel bundle is arranged in the bottom plate of the prestressed immersed tube segment and is distributed longitudinally along the prestressed immersed tube segment, the longitudinal support condition can be met, the first prestressed steel bundle has a first passing point corresponding to the first side wall, a second passing point corresponding to the first side wall and the first middle wall, a third passing point corresponding to the first middle wall and the second middle wall, a fourth passing point corresponding to the second middle wall and the second side wall, and a fifth passing point corresponding to the second side wall, and the first prestressed steel bundle is arranged in a wave shape in the vertical direction, the first passing point, the third passing point and the fifth passing point are wave troughs, and the second passing point and the fourth passing point are wave crests, so that all parts of the bottom plate can meet the support condition of the SPMT vehicle, the SPMT vehicle can be arranged below the bottom plate, sufficient support force can be provided when the prestressed immersed tube segment is transported by using the SPMT vehicle, the cracking degree of the prestressed immersed tube segment can be reduced, and the SPMT vehicle can be used to transport the immersed tube segment.

[0012] However, the arrangement of the first prestressed steel bundle causes the middle wall of the top plate to arch, that is, the stress of the top plate is affected, the second prestressed steel bundle arranged in the top plate can overcome the influence of the first prestressed steel bundle on the stress of the top plate, the arrangement forms of the first prestressed steel bundle and the second prestressed steel bundle are consistent with the load forms of the bottom plate and the top plate of the immersed tube segment in the operation period, the stress state of the immersed tube segment in the operation period is met, and the reinforcement amount of the bottom plate and the top plate can be reduced, thereby saving costs.

[0013] Preferably, the first passing point and the fifth passing point are arranged at the vertical center position of the bottom plate, and the sixth passing point and the tenth passing point are arranged at the vertical center position of the top plate, facilitating tensioning;

[0014] And / or, the distance between the second passing point and the fourth passing point and the top surface of the bottom plate is greater than or equal to the thickness of the reinforcement cover of the top surface of the bottom plate, the distance between the third passing point and the bottom surface of the bottom plate is greater than or equal to the thickness of the reinforcement cover of the bottom surface of the bottom plate, the distance between the seventh passing point and the bottom surface of the top plate is greater than or equal to the thickness of the reinforcement cover of the bottom surface of the top plate, and the distance between the eighth passing point and the top surface of the top plate is greater than or equal to the thickness of the reinforcement cover of the top surface of the top plate, ensuring the safety of the structure under stress;

[0015] And / or, the first prestressed steel bundle and the second prestressed steel bundle are both smooth curves, improving the prestressed tensioning quality;

[0016] And / or, the first prestressed steel bundle and the second prestressed steel bundle are arranged transversely symmetrically in the pipe section, which can better adapt to the transverse balanced arrangement of the pipe joint.

[0017] In the second aspect, the present application provides a design method of a prestressed pipe section, which is used for a prestressed pipe section and includes the following steps:

[0018] S01: Determine the preset position range of the on-ship support for supporting the prestressed pipe section on the semi-submersible barge and the fixed buttress when the prestressed pipe section is prefabricated, and exclude the transverse position of the corresponding prestressed pipe section when the SPMT vehicle transports the prestressed pipe section according to the preset position range of the on-ship support and the fixed buttress; then determine the number of required SPMT vehicles according to the weight of the prestressed pipe section; and then obtain all the layout position points of the corresponding prestressed pipe section of the required SPMT vehicles according to the number of required SPMT vehicles, the excluded transverse position when the SPMT vehicle transports the prestressed pipe section, and the layout requirement; in step S01, the layout requirement is that the SPMT vehicles are arranged in columns below the prestressed pipe section, and the SPMT vehicles are arranged transversely symmetrically below the prestressed pipe section;

[0019] S02: Determine the cross-sectional design of the first prestressed steel bundle and the second prestressed steel bundle and the setting position in the longitudinal direction of the prestressed pipe section according to the layout position points of the SPMT vehicles, and the design of the prestressed pipe section is completed.

[0020] It can meet the demand that the SPMT vehicle transports the prestressed pipe section under the bottom plate and the structural safety demand of the pipe section.

[0021] Preferably, step S02 includes the following steps:

[0022] S02.1: Obtain an equivalent immersed tube unit with a unit length in the longitudinal direction, the bottom plate, the top plate, the middle wall and the side wall of the equivalent immersed tube unit are equivalent to beam units, and the beam units are connected by rigid connection;

[0023] S02.2: Determine the position of the support force applied at the bottom of the equivalent immersed tube unit according to the layout position of the SPMT vehicle, simulate the support of the SPMT vehicle on the equivalent immersed tube unit, and establish a simplified calculation model of the equivalent immersed tube unit;

[0024] S02.3: Analyze the stress form of the simplified calculation model under the combined action of the support force and the gravity of the equivalent immersed tube unit, and obtain a first bending moment diagram;

[0025] S02.4: Correspondingly add a first prestressed steel tendon and a second prestressed steel tendon in the bottom plate and the top plate of the equivalent immersed tube unit, the first prestressed steel tendon and the second prestressed steel tendon being as claimed in any one of claims 1-2;

[0026] S02.5: Then change the cross-sectional area of the first prestressed steel tendon and the second prestressed steel tendon, and analyze the stress form of the simplified calculation model under the combined action of the support force, the prestress provided by the first prestressed steel tendon, the prestress provided by the second prestressed steel tendon and the gravity of the equivalent immersed tube unit, and obtain a second bending moment diagram;

[0027] S02.6: Judge the bending moment of the bottom plate and the top plate of the equivalent immersed tube unit, if the bending moment of the other parts of the bottom plate in the second bending moment diagram except the connection between the bottom plate and the side wall is not greater than the preset bending moment, and the bending moment of the top plate in the second bending moment diagram is not greater than the bending moment of the top plate in the first bending moment diagram, then the cross-sectional area of the first prestressed steel tendon and the second prestressed steel tendon meets the stress requirement of the equivalent immersed tube unit, the relationship between the cross-sectional area of the first prestressed steel tendon and the second prestressed steel tendon and the unit length is obtained, and S02.7 is entered, otherwise, steps S02.5 and S02.6 are repeated until S02.7 is entered;

[0028] S02.7: According to the relationship between the cross-sectional area of the first prestressed steel tendon and the second prestressed steel tendon and the unit length that meets the requirement, the number and longitudinal arrangement spacing of the steel strands of the first prestressed steel tendon and the second prestressed steel tendon are selected;

[0029] S02.8: According to the number and longitudinal arrangement spacing of the steel strands of the first prestressed steel tendon and the second prestressed steel tendon selected, a prestressed immersed tube segment SPMT vehicle transportation finite element model is established;

[0030] S02.9: analyze whether the stress of the pre-stressed pipe section meets the crack control requirement, if yes, complete the pre-stress design, determine the cross-section design of the first pre-stress steel beam and the second pre-stress steel beam and the setting position in the longitudinal direction of the pre-stressed pipe section; if not, re-adjust the number of steel strands of the steel beam or the longitudinal arrangement spacing, repeat steps S02.8 and S02.9 until the stress of the pipe section meets the crack control requirement, the pre-stress design is completed, and the cross-section design of the first pre-stress steel beam and the second pre-stress steel beam and the setting position in the longitudinal direction of the pre-stressed pipe section are obtained.

[0031] The above method can obtain the relationship between the cross-sectional area of the first pre-stress steel beam and the second pre-stress steel beam and the unit length that meets the requirements, and then adjust the number of steel strands and the longitudinal arrangement spacing of the first pre-stress steel beam and the second pre-stress steel beam, to obtain the cross-section design of the first pre-stress steel beam and the second pre-stress steel beam and the setting position in the longitudinal direction of the pre-stressed pipe section that meet the requirements more.

[0032] In a third aspect, the present application provides a SPMT car on-barge method for the pre-stressed pipe section on-barge, comprising the following steps:

[0033] S1, determine the preset position range of the on-ship support for supporting the pre-stressed pipe section on the semi-submersible barge and the fixed support pier during the prefabrication of the pre-stressed pipe section, exclude the transverse position of the corresponding pre-stressed pipe section when the SPMT car transports the pre-stressed pipe section according to the preset position range of the on-ship support and the fixed support pier; then determine the number of required SPMT cars according to the weight of the pre-stressed pipe section; and then obtain all the arrangement position points of the required SPMT cars corresponding to the pre-stressed pipe section according to the number of required SPMT cars, the excluded transverse position when the SPMT car transports the pre-stressed pipe section, and the arrangement requirement; in step S1, the arrangement requirement is that the SPMT cars are arranged in columns under the pre-stressed pipe section, and the SPMT cars are arranged symmetrically transversely to the pre-stressed pipe section;

[0034] S2, arrange the SPMT cars at the bottom of the pre-stressed pipe section according to the arrangement position points of the SPMT cars, and each column of the SPMT cars forms a car group, and sleepers are arranged on the car group;

[0035] S3, lift the pre-stressed pipe section by the SPMT cars, so that the pre-stressed pipe section is separated from the fixed support pier;

[0036] S4, drive the pre-stressed pipe section by the SPMT cars from the prefabrication plant to the semi-submersible barge through the wharf;

[0037] S5, lower the pre-stressed pipe section by the SPMT cars supporting the hydraulic cylinder until the pre-stressed pipe section falls on the on-ship support;

[0038] S6, the SPMT vehicle support hydraulic cylinder continues to descend, so that the sleeper does not contact the immersed tube segment;

[0039] S7, the SPMT vehicle retreats to the wharf, and the pre-stressed immersed tube segment is completed.

[0040] Among them, the sleeper is set to avoid direct contact between the SPMT vehicle and the pre-stressed immersed tube segment, and to avoid the large cracking process caused by the direct contact between the steel structure SPMT vehicle and the concrete of the pre-stressed immersed tube segment.

[0041] The above-mentioned SPMT vehicle loading method is adopted, which can be fully distributed under the bottom plate of the immersed tube segment by setting the transverse pre-stress of the immersed tube segment; after determining the layout position point of the SPMT vehicle, it can meet the support of the pre-stressed immersed tube segment and meet the carrying capacity during loading; and the transverse position of the SPMT vehicle on the pre-stressed immersed tube segment is set to be dislocated from the transverse position of the fixed buttress corresponding to the pre-stressed immersed tube segment, so that the SPMT vehicle can be arranged below the precast pre-stressed immersed tube segment after the precast pre-stressed immersed tube segment is completed, realizing the stress conversion of the fixed buttress and the SPMT vehicle; and the transverse position of the SPMT vehicle on the pre-stressed immersed tube segment is set to be dislocated from the transverse position of the ship support corresponding to the pre-stressed immersed tube segment, so that the SPMT vehicle can transport the pre-stressed immersed tube segment from the wharf to the semi-submersible barge without interference from the ship support, and then the pre-stressed immersed tube segment can be converted from the sleeper support on the SPMT vehicle to the ship support, and the SPMT vehicle continues to unload, so that the top of the vehicle group does not contact the immersed tube segment, so that the SPMT vehicle can retreat to the wharf, and then the SPMT vehicle realizes the overall loading process of the pre-stressed immersed tube segment. Because of the large stroke self-adaptive adjustment capability and walking flexibility of the SPMT vehicle, the cracking control difficulty of the immersed tube segment in the loading process is reduced.

[0042] Preferably, before step S2, it further includes a precast step of the pre-stressed immersed tube segment:

[0043] According to the layout position point of the SPMT vehicle, the arrangement position of the four columns of fixed buttresses is determined, so that the four columns of fixed buttresses are dislocated from the layout position point, and the fixed buttresses distributed along the transverse direction of the pre-stressed immersed tube segment are symmetrically arranged about the longitudinal center axis of the pre-stressed immersed tube segment; then the pre-stressed immersed tube segment is precasted, so that the two side walls and two middle walls of the pre-stressed immersed tube segment are correspondingly arranged on the four columns of fixed buttresses.

[0044] It can ensure the stress balance during precasting the pre-stressed immersed tube segment, and ensure good cracking control effect of the precast pre-stressed immersed tube segment.

[0045] Preferably, between steps S2 and S3, the vehicle group is divided into 4 zones along the transverse and longitudinal central axes of the pre-stressed pipe section, and the hydraulic suspension of all SPMT vehicles in each zone is connected in series through the oil pipe; the 4 zones are connected in parallel through the oil pipe;

[0046] In step S3, the vehicle group in the 4 zones is used to synchronously jack up the pre-stressed pipe section.

[0047] The 4-point synchronous jacking is formed, and the vehicle group in the 4 zones is used to synchronously jack up the pre-stressed pipe section, so that the stress on the bottom plate is uniform and hierarchical when the bottom plate is jacked up, and the crack control effect is improved.

[0048] Preferably, between steps S3 and S4, the vehicle group is divided into three zones, the vehicle group under the front half of the pre-stressed pipe section in the forward direction is taken as one zone, and the vehicle group under the rear half of the pre-stressed pipe section in the forward direction is divided into two zones along the longitudinal central axis of the pre-stressed pipe section; the hydraulic suspension of all SPMT vehicles in each zone is connected in series through the oil pipe, and the 3 zones are connected in parallel through the oil pipe;

[0049] In step S4, the vehicle group in the 3 zones is used to support the pre-stressed pipe section.

[0050] The 3-point synchronous jacking is formed, and the vehicle group in the 3 zones is used to support the pre-stressed pipe section, so that the three regions are always located in a plane when the bottom plate is jacked up, the stress is uniform, and the crack control effect is improved.

[0051] Preferably, before step S4, the semi-submersible barge is docked and moored at the wharf edge by a cable; then a 40mm-50mm thick steel plate is laid at the joint of the wharf and the semi-submersible barge; and then ship supports are arranged on the deck of the semi-submersible barge; wherein the transverse arrangement position of the ship supports on the semi-submersible barge is determined according to the arrangement position of the SPMT vehicles.

[0052] After the semi-submersible barge is docked and moored at the wharf edge by a cable, a 40mm-50mm thick steel plate is laid, which meets the requirements of the SPMT vehicles on the barge, and ship supports are arranged on the deck of the semi-submersible barge, which can ensure that the ship supports do not interfere with the movement of the SPMT vehicles on the barge.

[0053] Preferably, 8 columns of ship supports are arranged on the semi-submersible barge in transverse intervals, wherein 4 columns of ship supports correspond to the two side walls and two middle walls of the pre-stressed pipe section, and the other 4 columns of ship supports are located between adjacent two columns of SPMT vehicles, and the ship supports distributed transversely on the semi-submersible barge are symmetrically arranged about the longitudinal central axis of the pre-stressed pipe section.

[0054] After the pre-stressed pipe section is transferred from the wharf to the semi-submersible barge, it is placed on the 8 columns of ship supports, the stress on the deck of the semi-submersible barge is uniform and smaller during the conversion process, and the deformation of the deck of the semi-submersible barge is reduced.

[0055] Preferably, in step S4, the pre-stressed pipe section is transferred from the wharf to the semi-submersible barge by the SPMT vehicle in a pre-selected operation window.

[0056] In the process of transferring, the transferring speed is controlled within 0.5-1 m / min, and the difference in height between the wharf and the stern deck and the floating state of the semi-submersible barge are controlled by adjusting the ballast tank of the semi-submersible barge to meet the control requirements of the SPMT vehicle and the stability of the semi-submersible barge.

[0057] Compared with the prior art, the present application has the following advantages:

[0058] 1. The present application provides a pre-stressed pipe section, wherein a first pre-stressed steel beam is arranged in the bottom plate of the pre-stressed pipe section in a transverse direction, so that all parts of the bottom plate can meet the support conditions of the SPMT vehicle, and the SPMT vehicle can be fully arranged under the bottom plate, so that the pre-stressed pipe section transported by the SPMT vehicle can provide sufficient support force, and the degree of cracking of the pre-stressed pipe section can be reduced, and the SPMT vehicle can be used to transfer the pre-stressed pipe section; a second pre-stressed steel beam is arranged in the top plate in a transverse direction, the second pre-stressed steel beam can overcome the stress influence of the first pre-stressed steel beam on the top plate, and the arrangement form (direction) of the first pre-stressed steel beam and the second pre-stressed steel beam conforms to the load form of the bottom plate and the top plate of the pre-stressed pipe section in the operation period, so that the stress state of the pre-stressed pipe section in the operation period is met, and the reinforcement amount of the bottom plate and the top plate can be reduced, and the cost can be saved.

[0059] 2. The present application provides a design method of a pre-stressed pipe section, which can meet the demand that the SPMT vehicle fully arranges the pre-stressed pipe section under the bottom plate and the structural safety requirement of the pre-stressed pipe section.

[0060] 3. The application provides a SPMT car on-barge method, by arranging transverse prestress on the bottom plate of a immersed tube segment, so that the SPMT car can be fully arranged under the bottom plate; after determining the arrangement position of the SPMT car, the SPMT car can satisfy the support of the prestressed immersed tube segment and the bearing capacity during on-barging; the transverse position of the SPMT car on the prestressed immersed tube segment is arranged in a staggered manner with the transverse position of the fixed support pier on the prestressed immersed tube segment, so that the SPMT car can be arranged under the completed prestressed immersed tube segment after prefabrication, and the stress conversion of the fixed support pier and the SPMT car is realized; the transverse position of the SPMT car on the prestressed immersed tube segment is arranged in a staggered manner with the transverse position of the on-ship support on the prestressed immersed tube segment, so that the SPMT car can transport the prestressed immersed tube segment from the wharf to the semi-submersible barge without the interference of the on-ship support, and then the prestressed immersed tube segment can be converted from the support of the SPMT car on the sleeper to the on-ship support, and the SPMT car continues to unload, so that the top of the car group does not contact the sleeper, and the SPMT car can be withdrawn to the wharf, and then the SPMT car is used to realize the overall on-barging process of the prestressed immersed tube segment, and the cracking control difficulty of the immersed tube segment during the on-barging process is reduced due to the large stroke self-adaptive adjustment capability and the walking flexibility of the SPMT car. BRIEF DESCRIPTION OF DRAWINGS

[0061] Fig. 1 is a bending moment diagram of the immersed tube segment of the existing reinforced concrete immersed tube segment under the multi-support system;

[0062] Fig. 2 is a bending moment diagram of the immersed tube segment of the existing reinforced concrete immersed tube segment during operation;

[0063] Fig. 3 is a schematic diagram of the prestressed immersed tube segment of the application;

[0064] Fig. 4 is a schematic diagram of the prestressed immersed tube segment of the application;

[0065] Fig. 5 is a schematic diagram of tensioning of the prestressed immersed tube segment of the application;

[0066] Fig. 6 is a schematic diagram of the arrangement of the first and second prestressed steel strands of the prestressed immersed tube segment of the application;

[0067] Fig. 7 is a schematic diagram of the load form of the immersed tube segment during operation;

[0068] Fig. 8 is a schematic diagram of the structure form of the prestressed steel strand;

[0069] Fig. 9 is a schematic diagram of the structure form of the tensioning end;

[0070] Fig. 10 is a schematic diagram of support force control for facilitating cracking control of the immersed tube segment;

[0071] Fig. 11 is a schematic diagram of the arrangement of the fixed support pier during prefabrication;

[0072] Figure 12 is a schematic diagram of prefabricated SPMT vehicles and sleepers arranged under the base plate;

[0073] Figure 13 is a schematic diagram of SPMT vehicle partitioning when the force of the fixed pier is converted to the force of the SPMT vehicle;

[0074] Figure 14 is a schematic diagram of the load form of the SPMT vehicle transporting the immersed tube segment;

[0075] Figure 15 is a schematic diagram of the longitudinal arrangement of the SPMT vehicle and sleepers along the prestressed immersed tube segment;

[0076] Figure 16 is a schematic diagram of the partitioning of the SPMT vehicle transporting the prestressed immersed tube segment;

[0077] Figure 17 is a schematic diagram of the support force of the prestressed immersed tube segment under the support of the SPMT vehicle to meet the requirements of crack control;

[0078] Figure 18 is a schematic diagram of the stress of the prestressed immersed tube segment under the support of the SPMT vehicle to meet the requirements of crack control;

[0079] Figures 19-22 are schematic diagrams of the process of the SPMT vehicle transporting the prestressed immersed tube segment into the semi-submersible barge;

[0080] Figure 23 is a schematic diagram of the arrangement of the support on the ship;

[0081] Figure 24 is a schematic diagram of fixing the prestressed immersed tube segment in the semi-submersible barge;

[0082] Figure 25 is an equivalent immersed tube unit;

[0083] Figure 26 is a schematic diagram of a simplified calculation model;

[0084] Figure 27 is a schematic diagram of a first bending moment diagram;

[0085] Figure 28 is a schematic diagram of a second bending moment diagram;

[0086] Figure 29 is a schematic diagram of the cross section of the prestressed steel tendon;

[0087] Figure 30 is a schematic diagram of the finite element model of the SPMT vehicle transporting the immersed tube segment;

[0088] Figure 31 is a schematic diagram of the stress for analyzing whether the force of the immersed tube segment meets the requirements of crack control.

[0089] Marked in the figure: 1, pipe section of immersed tube; 11, top plate; 12, bottom plate; 13, first side wall; 14, first middle wall; 15, second middle wall; 16, second side wall; 21, first prestressed steel bundle; 211, first passing point; 212, second passing point; 213, third passing point; 214, fourth passing point; 215, fifth passing point; 22, second prestressed steel bundle; 221, sixth passing point; 222, seventh passing point; 223, eighth passing point; 224, ninth passing point; 225, tenth passing point; 23, tensioning end; 31, fixed buttress; 32, auxiliary buttress; 4, SPMT vehicle; 41, sleeper; 5, semi-submersible barge; 51, on-boat support; 6, wharf; 52, bottom steel support. DETAILED DESCRIPTION

[0090] The application will be further described below in connection with specific embodiments. However, it should be understood that the above-mentioned subject matter of the application is not limited to the following embodiments, and any technology implemented based on the content of the application falls within the scope of the application.

[0091] In the description of the embodiments of the application, the terms indicating the orientation or positional relationship of "up", "down", "left", "right", "center", "inner", "outer", and the like, are expressed based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product / device / apparatus of the application is usually placed. These terms of orientation or positional relationship are only for the convenience of describing the application or simplifying the description in the embodiments, and for the convenience of the skilled person to quickly understand the scheme, and therefore cannot be understood as indicating or implying that a specific device / component / element must have a specific orientation or be constructed and operated in a specific positional relationship, and therefore cannot be understood as limiting the application.

[0092] In addition, if the terms "horizontal", "vertical", "suspension", "parallel", and the like are used, it does not mean that the corresponding device / component / element must be absolutely horizontal or vertical or suspended or parallel, but can be slightly inclined or deviated. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. Alternatively, it can be simply understood that the corresponding device / component / element is arranged in the direction of "horizontal", "vertical", "suspension", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction, more preferably an error / deviation of ±8% or less, more preferably an error / deviation of ±6% or less, more preferably an error / deviation of ±5% or less, and more preferably an error / deviation of ±4% or less. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the application.

[0093] In addition, the terms "first", "second", "third" and the like in the description of embodiments of the present application are used only to distinguish similar or identical components, and should not be understood as emphasizing or implying the relative importance of the particular components.

[0094] In addition, in the description of embodiments of the present application, "several", "a plurality of", "several" represent at least 2. It can be 2, 3, 4, 5, 6, 7, 8, 9, etc. Any case, it can even be more than 9 cases.

[0095] In addition, in the description of the technical solutions of the present application, unless otherwise specified / limited / limited, the terms "set", "install", "connect", "connect", "set", "lay", "arrange" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, which can be welding, riveting, bolting, screwing, etc. The connection means commonly used in the art. This connection can be mechanical connection, or electrical connection or communication connection; it can be directly connected, or indirectly connected through an intermediate medium, or the communication between two elements.

[0096] Embodiment 1

[0097] In the prior art, as shown in Figures 1-7, the SPMT car 4 is used to move the immersed tube segment 1 and the semi-submersible barge 5 is used to transport the immersed tube segment 1. The immersed tube segment 1 is in a multi-support stress system (supported from the prefabricated fixed support 31 to the SPMT car 4 support for transportation, and then supported on the ship support 51 for transportation of the semi-submersible barge 5), which is quite different from the traditional dry dock water injection floating operation, and the stress form is also quite different. As shown in Figure 2, the bending moment of the immersed tube segment 1 during operation is mainly considered during design, while as shown in Figure 1, the bending moment of the immersed tube segment 1 under the multi-support system is not the same as that of the immersed tube segment 1 during operation, so that when the SPMT car 4 is used to move the immersed tube segment 1, it cannot be fully distributed at the bottom of the immersed tube segment 1, thereby the bearing capacity provided by the SPMT car 4 for moving the immersed tube segment 1 cannot be satisfied.

[0098] To solve the above problems, as shown in Figure 3, the present embodiment provides a prestressed immersed tube segment 1, which comprises a top plate 11, a bottom plate 12, a first side wall 13, a first middle wall 14, a second middle wall 15 and a second side wall 16. The first side wall 13, the first middle wall 14, the second middle wall 15 and the second side wall 16 are arranged in sequence along the immersed tube joint in the transverse direction. Its characteristic is that it comprises a first prestressed steel beam 21 and a second prestressed steel beam 22.

[0099] The first prestressed steel beam 21 is arranged in the bottom plate 12, and the first prestressed steel beam 21 is arranged in the transverse direction of the bottom plate 12. The first prestressed steel beam 21 is arranged in the longitudinal direction of the bottom plate 12.

[0100] The first prestressed steel strand 21 comprises a first passing point 211, a second passing point 212, a third passing point 213, a fourth passing point 214 and a fifth passing point 215, the first passing point 211 is located below the first side wall 13, the second passing point 212 is located between the first side wall 13 and the first middle wall 14, the third passing point 213 is located between the first middle wall 14 and the second middle wall 15, the fourth passing point 214 is located between the second middle wall 15 and the second side wall 16, and the fifth passing point 215 is located below the second side wall 16, the first prestressed steel strand 21 is arranged in a wave shape in the vertical direction, the first passing point 211, the third passing point 213 and the fifth passing point 215 are wave troughs, and the second passing point 212 and the fourth passing point 214 are wave crests;

[0101] The second prestressed steel strand 22 is arranged in the roof 11, the second prestressed steel strand 22 is arranged transversely along the roof 11, and the second prestressed steel strand 22 is distributed longitudinally along the roof 11;

[0102] The second prestressed steel strand 22 comprises a sixth passing point 221, a seventh passing point 222, an eighth passing point 223, a ninth passing point 224 and a tenth passing point 225, the sixth passing point 221 is located above the first side wall 13, the seventh passing point 222 is located between the first side wall 13 and the first middle wall 14, the eighth passing point 223 is located between the first middle wall 14 and the second middle wall 15, the ninth passing point 224 is located between the second middle wall 15 and the second side wall 16, and the tenth passing point 225 is located above the second side wall 16, the second prestressed steel strand 22 is arranged in a wave shape in the vertical direction, the sixth passing point 221, the eighth passing point 223 and the tenth passing point 225 are located at the wave crests, and the seventh passing point 222 and the ninth passing point 224 are located at the wave troughs.

[0103] The first transverse prestressed steel beam 21 is arranged in the bottom plate 12 of the prestressed immersed tube segment 1 and is spaced along the longitudinal direction of the prestressed immersed tube segment 1, which can meet the longitudinal support condition, and the first transverse prestressed steel beam 21 has a first passing point 211 corresponding to the first side wall 13, a second passing point 212 between the first side wall 13 and the first middle wall 14, a third passing point 213 between the first middle wall 14 and the second middle wall 15, a fourth passing point 214 between the second middle wall 15 and the second side wall 16, and a fifth passing point 215 corresponding to the second side wall 16, and the first transverse prestressed steel beam 21 is arranged in a wave shape in the vertical direction, the first passing point 211, the third passing point 213 and the fifth passing point 215 are wave troughs, and the second passing point 212 and the fourth passing point 214 are wave crests, so that the bottom plate 12 of the immersed tube segment 1 is greatly strengthened between the first side wall 13 and the first middle wall 14 and between the second middle wall 15 and the second side wall 16, and the bottom plate 12 of the immersed tube segment 1 is less strongly between the first side wall 13, the first middle wall 14 and the second middle wall 15 and the second side wall 16, so that all parts of the bottom plate 12 can meet the support condition of the SPMT vehicle 4, and the SPMT vehicle 4 can be filled under the bottom plate 12, so that the use of the SPMT vehicle 4 to transport the prestressed immersed tube segment 1 can provide sufficient support force, and the strength of the bottom of the bottom plate 12 can be ensured to be close to balanced, thereby reducing the degree of cracking of the prestressed immersed tube segment 1, and the SPMT vehicle 4 can be used to transport the immersed tube segment 1. The arrangement of the first transverse prestressed steel beam 21 in the bottom plate 12 can also reduce the reinforcement amount of the bottom plate 12 to a certain extent and save certain costs.

[0104] However, the arrangement of the first prestressed steel beam will cause the top plate to arch at the position of the corresponding middle wall, as shown in FIG. 3, which will affect the stress of the top plate. The arrangement of the transverse second prestressed steel beam in the top plate can overcome the influence of the first prestressed steel beam on the stress of the top plate, as shown in FIG. 4, and as shown in FIG. 7 and FIG. 2, the arrangement forms of the first prestressed steel beam and the second prestressed steel beam meet the load forms of the bottom plate and the top plate of the immersed tube segment in the operation period, meet the stress state of the immersed tube segment in the operation period, and can also reduce the reinforcement amount of the bottom plate and the top plate and save costs.

[0105] As shown in FIG. 8 and FIG. 9, the first prestressed steel beam 21 and the second prestressed steel beam 22 are also provided with tensioning ends 23 at both ends, which can tension the first prestressed steel beam 21 and the second prestressed steel beam 22 to provide sufficient prestress. As shown in FIG. 4, the first passing point and the fifth passing point are arranged at the vertical center position of the bottom plate, and the sixth passing point and the tenth passing point are arranged at the vertical center position of the top plate, which is convenient for tensioning. The first prestressed steel beam and the second prestressed steel beam are both smooth curves, which can improve the prestress tensioning quality. The first prestressed steel beam 21 and the second prestressed steel beam 22 can also be steel strands, as shown in FIG. 8.

[0106] The first and second prestressed steel bars are arranged symmetrically in the transverse direction of the pipe section, which can better adapt to the transverse balanced arrangement of the pipe joint. The prestressed steel bars are symmetrically designed, such as the first prestressed steel bar, i.e., the first passing point and the fifth passing point, and the second passing point and the fourth passing point are symmetrically arranged. The first passing point and the fifth passing point are arranged at the center position of the bottom plate (which can be adjusted appropriately), which is beneficial to the operation of the prestressed tensioning construction. The second passing point, the third passing point, and the fourth passing point are arranged as close to the upper or lower surface of the bottom plate as possible while meeting the structural requirements of the prestressed pipe and the thickness of the steel reinforcement protective layer. The prestressed steel bar is designed as a smooth curve through the five passing points.

[0107] Further, the distance between the second passing point and the fourth passing point and the top surface of the bottom plate is greater than or equal to the thickness of the steel reinforcement protective layer of the top surface of the bottom plate, the distance between the third passing point and the bottom surface of the bottom plate is greater than or equal to the thickness of the steel reinforcement protective layer of the bottom surface of the bottom plate, the distance between the seventh passing point and the ninth passing point and the bottom surface of the top plate is greater than or equal to the thickness of the steel reinforcement protective layer of the bottom surface of the top plate, and the distance between the eighth passing point and the top surface of the top plate is greater than or equal to the thickness of the steel reinforcement protective layer of the top surface of the top plate, which ensures the safety of the structure under stress. Among them, the distance between the second passing point and the fourth passing point and the top surface of the bottom plate is equal to the thickness of the steel reinforcement protective layer of the top surface of the bottom plate, the distance between the third passing point and the bottom surface of the bottom plate is equal to the thickness of the steel reinforcement protective layer of the bottom surface of the bottom plate, the distance between the seventh passing point and the ninth passing point and the bottom surface of the top plate is equal to the thickness of the steel reinforcement protective layer of the bottom surface of the top plate, and the distance between the eighth passing point and the top surface of the top plate is equal to the thickness of the steel reinforcement protective layer of the top surface of the top plate, which can maximize the setting of prestress and reduce the setting of reinforcement.

[0108] The embodiment not only considers the full design of the SPMT car 4, but also considers the stress characteristics of the immersed tunnel during operation. The prestressed steel bar can meet the stress requirements of the immersed pipe section 1 during operation, and can also resist the load of the SPMT car 4. This design can prevent the immersed pipe section 1 from cracking, and can greatly reduce the reinforcement of the reinforced concrete.

[0109] Embodiment 2

[0110] The embodiment provides a design method of a prestressed immersed pipe section 1, which is used for designing the prestressed immersed pipe section 1 in embodiment 1, and includes the following steps:

[0111] S01: determine the preset position range of the on-ship support 51 on the semi-submersible barge 5 for supporting the pre-stressed immersed tube segment 1 and the fixed support pier 31 during the prefabrication of the pre-stressed immersed tube segment 1, exclude the transverse position of the corresponding pre-stressed immersed tube segment 1 when the SPMT vehicle 4 transports the pre-stressed immersed tube segment 1 according to the preset position range of the on-ship support 51 and the fixed support pier 31, then determine the number of required SPMT vehicles 4 according to the weight of the pre-stressed immersed tube segment 1, and then obtain all the layout position points of the required SPMT vehicles 4 corresponding to the pre-stressed immersed tube segment 1 according to the number of required SPMT vehicles 4, the excluded transverse position when the SPMT vehicle 4 transports the pre-stressed immersed tube segment 1, and the layout requirement; in step S01, the layout requirement is that the SPMT vehicles 4 are arranged in a column below the pre-stressed immersed tube segment 1, and the SPMT vehicles 4 are arranged symmetrically transversely to the pre-stressed immersed tube segment 1.

[0112] S02: determine the cross-sectional design of the first pre-stressed steel strand and the second pre-stressed steel strand and the setting position in the longitudinal direction of the pre-stressed immersed tube segment according to the layout position points of the SPMT vehicles, and the design of the pre-stressed immersed tube segment is completed.

[0113] Optionally, step S02 includes the following steps:

[0114] S02.1: as shown in FIG. 25, an equivalent immersed tube unit with a longitudinal direction as a unit length is obtained, the bottom plate, top plate, middle wall and side wall of the equivalent immersed tube unit are equivalent to beam units, and the beam units are connected rigidly;

[0115] S02.2: the position of applying a support force at the bottom of the equivalent immersed tube unit is determined according to the layout position points of the SPMT vehicles, the support of the SPMT vehicles on the equivalent immersed tube unit is simulated, and a simplified calculation model of the equivalent immersed tube unit is established, as shown in FIG. 26;

[0116] S02.3: the stress form of the simplified calculation model under the combined action of the support force and the gravity of the equivalent immersed tube unit is analyzed, and a first bending moment diagram is obtained, as shown in FIG. 27;

[0117] S02.4: a first pre-stressed steel strand and a second pre-stressed steel strand of the pre-stressed immersed tube segment according to any one of claims 1-2 are additionally arranged in the bottom plate and the top plate of the equivalent immersed tube unit;

[0118] S02.5: then the cross-sectional area of the first pre-stressed steel strand and the second pre-stressed steel strand is changed, and the stress form of the simplified calculation model under the combined action of the support force, the pre-stress provided by the first pre-stressed steel strand, the pre-stress provided by the second pre-stressed steel strand and the gravity of the equivalent immersed tube unit is analyzed again, and a second bending moment diagram is obtained, as shown in FIG. 28;

[0119] S02.6: judging the bending moment of the bottom plate and the top plate of the equivalent pipe jacking unit, if the bending moment of the bottom plate in the second bending moment diagram except the connection between the bottom plate and the side wall is not greater than the preset bending moment, and the bending moment of the top plate in the second bending moment diagram is not greater than the bending moment of the top plate in the first bending moment diagram, then the cross-sectional area of the first prestressed steel and the second prestressed steel meets the stress requirement of the equivalent pipe jacking unit, the relationship between the cross-sectional area of the first prestressed steel and the second prestressed steel and the unit length is obtained, and S02.7 is entered, otherwise, steps S02.5 and S02.6 are repeated until S02.7 is entered;

[0120] S02.7: selecting the number of steel strands and the longitudinal arrangement spacing of the first prestressed steel and the second prestressed steel according to the relationship between the cross-sectional area of the first prestressed steel and the second prestressed steel and the unit length that meets the requirement;

[0121] S02.8: establishing a prestressed pipe jacking pipe joint SPMT vehicle transportation finite element model according to the selected number of steel strands and the longitudinal arrangement spacing of the first prestressed steel and the second prestressed steel, as shown in FIG. 30;

[0122] S02.9: as shown in FIG. 31, analyzing whether the stress of the prestressed pipe jacking pipe joint meets the crack control requirement, if yes, completing the prestressed design, and determining the cross-sectional design of the first prestressed steel and the second prestressed steel and the setting position in the longitudinal direction of the prestressed pipe jacking pipe joint; if not, re-adjusting the number of steel strands or the longitudinal arrangement spacing of the steel strands, repeating steps S02.8 and S02.9, until the stress of the pipe jacking pipe joint meets the crack control requirement, the prestressed design is completed, and the cross-sectional design of the first prestressed steel and the second prestressed steel and the setting position in the longitudinal direction of the prestressed pipe jacking pipe joint are obtained.

[0123] The above method can adjust the number of steel strands and the longitudinal arrangement spacing of the first prestressed steel and the second prestressed steel by obtaining the relationship between the cross-sectional area of the first prestressed steel and the second prestressed steel and the unit length that meets the requirement, and obtain the cross-sectional design of the first prestressed steel and the second prestressed steel and the setting position in the longitudinal direction of the prestressed pipe jacking pipe joint that meet the requirement more.

[0124] For the above S02.1-S02.9, this embodiment provides a specific design case, taking the unit length as 1m for example:

[0125] (1) Simplified calculation model of prestressed design

[0126] Take 1m long immersed tube section, the floor, roof, middle wall, side wall of 1m long immersed tube section are equivalent to beam unit, such as the floor is 1.65m high, the floor is equivalent to beam unit with cross section of 1.65m*1m, the beam units are connected by rigid connection to form equivalent immersed tube unit, as shown in Figure 25, a simplified calculation model is established according to the equivalent immersed tube unit, as shown in Figure 26.

[0127] The support force is applied according to the position of the SPMT vehicle, the weight of the 1m immersed tube section is G, and n rows of SPMT vehicles are arranged, so the support force of the SPMT vehicle is G / n.

[0128] (2) The stress form of the simplified calculation model under the action of the SPMT vehicle support and gravity is analyzed, and the first bending moment diagram is shown in Figure 27.

[0129] (3) The transverse prestress (first and second prestress tendons) is added in the floor and top, and the prestress form meets the related setting (structure form) in embodiment 1. The cross-sectional area of the prestress tendon is changed, the stress form of the simplified calculation model under the combined action of the SPMT vehicle support, prestress and gravity is analyzed, and the second bending moment diagram is obtained, as shown in Figure 28. Until the following two requirements are met: ① The floor bending moment tends to zero as much as possible (except for the connection between the floor and the side wall), and the floor bending moment is small, i.e. lower than the preset bending moment. ② The roof bending moment is not greater than the bending moment under the action of the SPMT vehicle support and gravity, i.e. not greater than the bending moment of the roof in the first bending moment diagram.

[0130] (4) According to the calculated cross-sectional area, the number of prestress tendons or the longitudinal arrangement mode is adjusted to design the prestress. For example, the calculated cross-sectional areas of the floor and roof prestress are 2400mm² and 1200mm² respectively, and the cross-sectional area of a single steel strand is 140mm². Therefore, a prestress tendon composed of 17 steel strands with a cross-sectional area of 2380mm² can be used, and the longitudinal arrangement spacing of the floor and roof prestress tendons is 1m and 2m respectively. The number of prestress tendon steel strands determines the cross-sectional area, as shown in Figure 29.

[0131] (5) According to the designed prestress tendon, an immersed tube section SPMT vehicle transportation finite element model is established, as shown in Figure 30, and whether the stress of the immersed tube section meets the crack control requirements is analyzed, as shown in Figure 31. If it meets the requirements, the prestress design is completed, otherwise the number of steel strands or the longitudinal arrangement spacing of the steel strands is adjusted until the stress of the immersed tube section meets the crack control requirements and the prestress design is completed.

[0132] The advantages of the prestressed immersed tube section obtained after the above design are as follows:

[0133] (1) The crack control requirements of the immersed tube section during SPMT vehicle transportation can be met.

[0134] (2) Considering that the load form on the bottom plate of the immersed tube segment in the operation period is the same as the load form when the SPMT vehicle is supported (similar to the uniform load), adding prestress in the top plate and the bottom plate is beneficial to the stress safety of the immersed tube segment in the operation period.

[0135] Embodiment 3

[0136] The embodiment provides a method for loading the prestressed immersed tube segment 1 onto the SPMT vehicle 4, and the method comprises the following steps:

[0137] S1, determining the preset position range of the on-ship support 51 for supporting the prestressed immersed tube segment 1 on the semi-submersible barge 5 and the fixed support pier 31 during prefabrication of the prestressed immersed tube segment 1, and excluding the transverse position of the corresponding prestressed immersed tube segment 1 when the SPMT vehicle 4 transports the prestressed immersed tube segment 1 according to the preset position range of the on-ship support 51 and the fixed support pier 31; then determining the number of required SPMT vehicles 4 according to the weight of the prestressed immersed tube segment 1; and then obtaining all layout position points of the required SPMT vehicles 4 corresponding to the prestressed immersed tube segment 1 according to the number of required SPMT vehicles 4, the excluded transverse position when the SPMT vehicle 4 transports the prestressed immersed tube segment 1, and the layout requirement; in step S1, the layout requirement is that the SPMT vehicle 4 is arranged in a column below the prestressed immersed tube segment 1, and the SPMT vehicle 4 is arranged in transverse symmetry with respect to the prestressed immersed tube segment 1;

[0138] Before step S2, the method further comprises a prefabrication step of the prestressed immersed tube segment 1:

[0139] According to the layout position points of the SPMT vehicle 4, the arrangement positions of the four columns of fixed support piers 31 are determined, so that the four columns of fixed support piers 31 are arranged in a staggered manner with the layout position points, and the fixed support piers 31 distributed along the transverse direction of the prestressed immersed tube segment 1 are arranged in symmetry with respect to the longitudinal central axis of the prestressed immersed tube segment 1; then the prestressed immersed tube segment 1 is prefabricated, so that the two side walls and the two middle walls of the prestressed immersed tube segment 1 are arranged on the four columns of fixed support piers 31, as shown in FIG. 11. This can ensure the stress balance during prefabrication of the prestressed immersed tube segment 1, and ensure that the crack control effect of the prefabricated prestressed immersed tube segment 1 is good.

[0140] Optionally, an auxiliary support pier 32 can be arranged between the four columns of fixed support piers 31, as shown in FIG. 10. The auxiliary support pier 32 also needs to be arranged in a staggered manner with the layout position points of the SPMT vehicle 4, and the auxiliary support pier 32 cannot be used as a main support area. The purpose of the auxiliary support pier 32 is to ensure that the bottom plate 12 tends to be horizontal, and the support force needs to be relatively small, which is conducive to the support force control for crack control of the immersed tube segment 1.

[0141] After the prefabrication of the immersed tube segment 1, the immersed tube segment 1 is placed on the fixed support pier 31. The arrangement of the fixed support pier 31 needs to consider the support and walking requirements of the SPMT vehicle 4. The fixed support pier 31 is arranged at the position of the side wall and the middle wall and is uniformly arranged along the longitudinal direction of the immersed tube segment 1. One is arranged every 2m.

[0142] The SPMT vehicle 4 drives to the position below the immersed tube segment 1. The SPMT vehicle 4 is arranged along the longitudinal direction of the immersed tube segment 1. The vehicle group is symmetrically arranged along the transverse direction of the immersed tube segment 1. The SPMT vehicle 4 group needs to meet the bearing requirements of the immersed tube segment 1. In addition, the arrangement of the SPMT vehicle 4 needs to avoid the fixed support pier 31 and the on-ship support 51 to ensure the smooth walking track of the SPMT vehicle 4.

[0143] For example, the immersed tube segment 1 weighs 34,000 tons. The SPMT vehicle 4 needs 1020 axles, 15 columns, 60 axles per column, and the load capacity is about 40,000 tons, which is greater than the total weight of the immersed tube segment 1, meeting the load requirements.

[0144] S2, according to the arrangement position of the SPMT vehicle 4, the SPMT vehicle 4 is arranged at the bottom of the prestressed immersed tube segment 1. Each column of the SPMT vehicle 4 forms a vehicle group. Sleeper 41 is arranged on the vehicle group, as shown in FIG. 12. The sleepers 41 are equally spaced along the longitudinal direction of the immersed tube segment 1. One is arranged every 2m.

[0145] S3, the prestressed immersed tube segment 1 is lifted by the SPMT vehicle 4, so that the prestressed immersed tube segment 1 is separated from the fixed support pier 31, as shown in FIG. 14 and FIG. 15.

[0146] Optionally, between steps S2 and S3, the vehicle group is divided into four zones along the transverse center axis and the longitudinal center axis of the prestressed immersed tube segment 1, as shown in FIG. 13. The hydraulic suspension of all SPMT vehicles 4 in each zone is connected in series through the oil pipe. The four zones are connected in parallel through the oil pipe.

[0147] In step S3, the vehicle group of the four zones is used to synchronously lift the prestressed immersed tube segment 1. Four-point synchronous lifting is formed. The vehicle group of the four zones is used to synchronously lift the prestressed immersed tube segment 1, which ensures that the stress of the bottom plate 12 is uniform and hierarchical when it is lifted, and improves the crack control effect. Specifically, the SPMT vehicle 4 is lifted. The support of the immersed tube segment 1 is converted from the fixed support pier 31 to the SPMT vehicle 4. In the lifting process, the four zones are synchronously lifted in stages. The SPMT vehicle 4 group is divided into four zones. The hydraulic suspension in each zone is connected in series through the oil pipe. The zones are connected in parallel through the oil pipe, thereby forming a self-adaptive four-point support.

[0148] Before step S4, the semi-submersible barge 5 is stern-against and moored by cables at the edge of the wharf 6; then a 40mm-50mm thick steel plate is laid at the joint of the wharf 6 and the semi-submersible barge 5; and then the on-board supports 51 are arranged on the deck surface of the semi-submersible barge 5; wherein the lateral arrangement position of the on-board supports 51 on the semi-submersible barge 5 is determined according to the arrangement position of the SPMT vehicles 4. After the semi-submersible barge 5 is stern-against and moored by cables at the edge of the wharf 6, a 40mm-50mm thick steel plate is laid, which meets the requirements of the SPMT vehicles 4 to be loaded on the barge, and the on-board supports 51 are arranged on the deck surface of the semi-submersible barge 5, which can avoid the misalignment of the on-board supports 51 and the SPMT vehicles 4 caused by the mooring position error of the semi-submersible barge 5, and can ensure that the on-board supports 51 do not interfere with the movement of the SPMT vehicles 4 to be loaded on the barge.

[0149] Further, as shown in FIG. 23, the on-board supports 51 are arranged in 8 columns laterally on the semi-submersible barge 5, wherein 4 columns of the on-board supports 51 correspond to the two side walls and the two middle walls of the pre-stressed immersed tube segment 1, and the other 4 columns of the on-board supports 51 are located between the adjacent two columns of the SPMT vehicles 4, and the on-board supports 51 distributed laterally on the semi-submersible barge 5 are symmetrically arranged about the longitudinal center axis of the pre-stressed immersed tube segment 1. After the pre-stressed immersed tube segment 1 is loaded on the barge from the wharf 6 to the semi-submersible barge 5 and placed on the 8 columns of the on-board supports 51, the stress on the deck of the semi-submersible barge 5 during the conversion process is uniform and smaller, which reduces the deformation of the deck of the semi-submersible barge 5. The on-board supports 51 are arranged at equal intervals longitudinally, with one row arranged every 2m.

[0150] S4, the pre-stressed immersed tube segment is loaded on the barge from the prefabrication plant to the semi-submersible barge by the SPMT vehicles; as shown in FIGS. 17-18, under the support of the SPMT vehicles 4, the stress on the immersed tube segment 1 meets the requirements of crack control.

[0151] Optionally, between steps S3-S4, the vehicle group is divided into three zones, as shown in FIG. 16, the vehicle group below the front half of the pre-stressed immersed tube segment 1 in the advancing direction is taken as one zone, and the vehicle group below the rear half of the pre-stressed immersed tube segment 1 in the advancing direction is divided into two zones along the longitudinal center axis of the pre-stressed immersed tube segment 1; the hydraulic suspensions of all the SPMT vehicles 4 in each zone are connected in series through the oil pipes, and the three zones are connected in parallel through the oil pipes.

[0152] In step S4, the vehicle groups of the three zones support the pre-stressed immersed tube segment 1. Three-point synchronous jacking is formed, and the vehicle groups of the three zones support the pre-stressed immersed tube segment 1, which ensures that the three zones are always located in one plane when the bottom plate 12 is jacked, the stress is uniform, and the crack control effect can be improved.

[0153] In step S4, as shown in FIGS. 19-22, the pre-stressed pipe section 1 is transferred from the wharf 6 to the semi-submersible barge 5 by the SPMT vehicle 4 in a pre-selected operation window; through theoretical analysis, a suitable operation window (not much wind and wave, suitable tidal level change) is selected as the pre-selected operation window;

[0154] In the process of loading, the loading speed is controlled within 0.5 m / min to 1 m / min, and the ballast tank of the semi-submersible barge 5 is adjusted to control the height difference between the wharf 6 side and the stern deck surface and the floating state of the semi-submersible barge 5 to meet the control requirements of the walking of the SPMT vehicle 4 and the stability safety of the semi-submersible barge 5. The floating state of the semi-submersible barge 5 includes roll and pitch. Specifically, the height difference between the wharf 6 side and the stern deck surface of the semi-submersible barge 5 is controlled within ±5 cm, and the roll and pitch of the semi-submersible barge 5 is controlled within 1°.

[0155] S5, the pre-stressed pipe section is lowered by the SPMT vehicle support hydraulic cylinder until it falls on the support on the ship;

[0156] S6, the SPMT vehicle support hydraulic cylinder continues to descend, so that the sleeper does not contact the pipe section;

[0157] S7, the SPMT vehicle retreats to the wharf, and the pre-stressed pipe section loading is completed.

[0158] The sleeper 41 is set to avoid direct contact between the SPMT vehicle 4 and the pre-stressed pipe section 1, and to avoid the large cracking process caused by the direct contact between the steel structure of the SPMT vehicle 4 and the concrete of the pre-stressed pipe section 1.

[0159] As shown in FIG. 24, after the pipe section loading is completed, the semi-submersible barge 5 is sealed and reinforced. The bottom steel support 52 is used as the main limiting device for sealing and reinforcing, supplemented by steel wire ropes. After the pipe section 1 is in place, the forklift places the bottom steel support 52 at the specified position, and the steel wire ropes are further tightened by using the basket screws.

[0160] The SPMT vehicle 4 upper barge method in the embodiment greatly expands the supportable area by arranging the transverse prestress on the bottom plate 12 of the immersed tube segment 1, reduces the control requirement of the support force, enables the SPMT vehicle 4 to be fully arranged under the bottom plate 12, determines the arrangement position of the SPMT vehicle 4, and enables the SPMT vehicle 4 to meet the support of the prestressed immersed tube segment 1 and the bearing capacity during the upper barge; the SPMT vehicle 4 is arranged in a staggered manner with the transverse position of the prestressed immersed tube segment 1 corresponding to the transverse position of the fixed support pier 31, so that the SPMT vehicle 4 can be arranged under the completed prestressed immersed tube segment 1 after the prefabrication of the prestressed immersed tube segment 1, realizes the stress conversion of the fixed support pier 31 and the SPMT vehicle 4; the SPMT vehicle 4 is arranged in a staggered manner with the transverse position of the prestressed immersed tube segment 1 corresponding to the transverse position of the ship support 51, so that the SPMT vehicle 4 can transport the prestressed immersed tube segment 1 from the wharf 6 to the semi-submersible barge 5 without the interference of the ship support 51, and then the prestressed immersed tube segment 1 can be converted from the support of the SPMT vehicle 4 to the support of the ship support 51, and the SPMT vehicle 4 continues to unload the force, so that the top of the vehicle group does not contact the immersed tube segment, and the SPMT vehicle 4 can be withdrawn to the wharf 6, thereby realizing the whole upper barge process of the prestressed immersed tube segment 1 by using the SPMT vehicle 4, and the process reduces the crack control difficulty of the immersed tube segment 1 during the upper barge process due to the large stroke adaptive adjustment capability and the walking flexibility of the SPMT vehicle 4.

[0161] The application greatly expands the supportable area by arranging the transverse prestress on the bottom plate 12 of the immersed tube segment 1, reduces the control requirement of the support force, enables the SPMT vehicle 4 to be fully arranged under the bottom plate 12, and then realizes the whole upper barge process of the prestressed immersed tube segment 1 by using the SPMT vehicle 4, and the process reduces the crack control difficulty of the immersed tube segment 1 during the upper barge process due to the large stroke adaptive adjustment capability and the walking flexibility of the SPMT vehicle 4.

[0162] The above only describes the preferred embodiments of the application and is not used to limit the application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A pre-stressed pipe section for a pipe, comprising a top plate, a bottom plate, a first side wall, a first middle wall, a second middle wall and a second side wall, the first side wall, the first middle wall, the second middle wall and the second side wall being arranged in a lateral sequence along the pipe joint, characterized in that, The first prestressed steel strand and the second prestressed steel strand are arranged in the bottom plate and the top plate. The first prestressed steel strand is arranged in the bottom plate and is arranged transversely along the bottom plate and is arranged spacedly longitudinally along the bottom plate. The first prestressed steel strand comprises a first passing point, a second passing point, a third passing point, a fourth passing point and a fifth passing point, the first passing point is arranged below the first side wall, the second passing point is arranged between the first side wall and the first middle wall, the third passing point is arranged between the first middle wall and the second middle wall, the fourth passing point is arranged between the second middle wall and the second side wall, and the fifth passing point is arranged below the second side wall, the first prestressed steel strand is arranged in a wave shape in the vertical direction, the first passing point, the third passing point and the fifth passing point are wave troughs, and the second passing point and the fourth passing point are wave crests. The second prestressed steel strand is arranged in the top plate and is arranged transversely along the top plate and is arranged spacedly longitudinally along the top plate. The second prestressed steel strand comprises a sixth passing point, a seventh passing point, an eighth passing point, a ninth passing point and a tenth passing point, the sixth passing point is arranged above the first side wall, the seventh passing point is arranged between the first side wall and the first middle wall, the eighth passing point is arranged between the first middle wall and the second middle wall, the ninth passing point is arranged between the second middle wall and the second side wall, and the tenth passing point is arranged above the second side wall, the second prestressed steel strand is arranged in a wave shape in the vertical direction, the sixth passing point, the eighth passing point and the tenth passing point are arranged at wave crests, and the seventh passing point and the ninth passing point are arranged at wave troughs.

2. A pre-stressed pipe section according to claim 1, wherein The first passing point and the fifth passing point are arranged at the vertical center of the bottom plate, and the sixth passing point and the tenth passing point are arranged at the vertical center of the top plate. And / or, the distance between the second passing point and the fourth passing point and the top surface of the bottom plate is greater than or equal to the thickness of the reinforcement protection layer of the top surface of the bottom plate, the distance between the third passing point and the bottom surface of the bottom plate is greater than or equal to the thickness of the reinforcement protection layer of the bottom surface of the bottom plate, the distance between the seventh passing point and the ninth passing point and the bottom surface of the top plate is greater than or equal to the thickness of the reinforcement protection layer of the bottom surface of the top plate, and the distance between the eighth passing point and the top surface of the top plate is greater than or equal to the thickness of the reinforcement protection layer of the top surface of the top plate. And / or, the first prestressed steel strand and the second prestressed steel strand are smooth curves. And / or, the first prestressed steel strand and the second prestressed steel strand are arranged symmetrically transversely in the pipe section.

3. A method of designing a pre-stressed pipe section, characterized in that, The method for designing the prestressed pipe section of any one of claims 1-2 comprises the following steps: The method for designing the prestressed pipe section of any one of claims 1-2 comprises the following steps: S01: determining the preset position range of the on-ship support for supporting the pre-stressed immersed tube segment on the semi-submersible barge and the fixed support during the precasting of the pre-stressed immersed tube segment, excluding the transverse position of the corresponding pre-stressed immersed tube segment when the SPMT vehicle transports the pre-stressed immersed tube segment according to the preset position range of the on-ship support and the fixed support, then determining the number of required SPMT vehicles according to the weight of the pre-stressed immersed tube segment, and then obtaining all the layout position points of the required SPMT vehicles corresponding to the pre-stressed immersed tube segment according to the number of the required SPMT vehicles, the excluded transverse position when the SPMT vehicle transports the pre-stressed immersed tube segment, and the layout requirement; in step S01, the layout requirement is that the SPMT vehicles are arranged in a column below the pre-stressed immersed tube segment, and the SPMT vehicles are arranged symmetrically in the transverse direction of the pre-stressed immersed tube segment; S02: determining the cross-sectional design of the first pre-stressed steel strand and the setting position in the longitudinal direction of the pre-stressed immersed tube segment according to the layout position points of the SPMT vehicles, and the design of the pre-stressed immersed tube segment is completed.

4. The method of designing a segmental prestressed pipe of a immersed tube according to claim 3, characterized in that, Step S02 includes the following steps: S02.1: obtaining an equivalent immersed tube unit with a longitudinal unit length, the bottom plate, top plate, middle wall, and side wall of the equivalent immersed tube unit are equivalent to beam units, and the beam units are connected rigidly; S02.2: determining the position of the support force applied at the bottom of the equivalent immersed tube unit according to the layout position points of the SPMT vehicles, simulating the support of the SPMT vehicles on the equivalent immersed tube unit, and establishing a simplified calculation model of the equivalent immersed tube unit; S02.3: analyzing the stress form of the simplified calculation model under the combined action of the support force and the gravity of the equivalent immersed tube unit, and obtaining a first bending moment diagram; S02.4: additionally adding a first pre-stressed steel strand and a second pre-stressed steel strand in the bottom plate and the top plate of the equivalent immersed tube unit according to any one of the pre-stressed immersed tube segments as claimed in claims 1-2; S02.5: then changing the cross-sectional area of the first pre-stressed steel strand and the second pre-stressed steel strand, and then analyzing the stress form of the simplified calculation model under the combined action of the support force, the pre-stress provided by the first pre-stressed steel strand, the pre-stress provided by the second pre-stressed steel strand, and the gravity of the equivalent immersed tube unit, and obtaining a second bending moment diagram; S02.6: judging the bending moment of the bottom plate and the top plate of the equivalent immersed tube unit, if the bending moment of the other parts of the bottom plate in the second bending moment diagram except the connection between the bottom plate and the side wall is not greater than a preset bending moment, and the bending moment of the top plate in the second bending moment diagram is not greater than the bending moment of the top plate in the first bending moment diagram, then the cross-sectional area of the first pre-stressed steel strand and the second pre-stressed steel strand meets the stress requirement of the equivalent immersed tube unit, the relationship between the cross-sectional area of the first pre-stressed steel strand and the second pre-stressed steel strand and the unit length is obtained, and step S02.7 is entered, otherwise, steps S02.5 and S02.6 are repeated until step S02.7 is entered; S02.7: selecting the number of steel strands and the longitudinal layout spacing of the first pre-stressed steel strand and the second pre-stressed steel strand according to the relationship between the cross-sectional area of the first pre-stressed steel strand and the second pre-stressed steel strand that meets the requirement and the unit length. S02.8: Establishing a finite element model of SPMT truck transportation of the prestressed pipe section according to the number and longitudinal arrangement spacing of the steel strands of the selected first prestressed steel strand and second prestressed steel strand; S02.9: Analyzing whether the stress of the prestressed pipe section meets the crack control requirements, and if so, completing the prestress design, determining the cross-section design of the first prestressed steel strand and the second prestressed steel strand and the setting position in the longitudinal direction of the prestressed pipe section; if not, re-adjusting the number of steel strands or the longitudinal arrangement spacing of the steel strands, repeating steps S02.8 and S02.9 until the stress of the pipe section meets the crack control requirements, the prestress design is completed, and the cross-section design of the first prestressed steel strand and the second prestressed steel strand and the setting position in the longitudinal direction of the prestressed pipe section are obtained.

5. A method of SPMT on-carriage transfer, characterized by, The method for the prestressed pipe section barge of any one of claims 1-2 comprises the following steps: S1, determining the preset position range of the on-ship support for supporting the prestressed pipe section on the semi-submersible barge and the fixed buttress during the prefabrication of the prestressed pipe section, excluding the transverse position of the corresponding prestressed pipe section during the SPMT truck transportation of the prestressed pipe section according to the preset position range of the on-ship support and the fixed buttress; then determining the number of required SPMT trucks according to the weight of the prestressed pipe section; and then obtaining all the arrangement position points of the required SPMT trucks corresponding to the prestressed pipe section according to the number of required SPMT trucks, the excluded transverse position during the SPMT truck transportation of the prestressed pipe section, and the arrangement requirement; in step S1, the arrangement requirement is to arrange the SPMT trucks in columns under the prestressed pipe section and to arrange the SPMT trucks symmetrically in the transverse direction of the prestressed pipe section; S2, arranging the SPMT trucks at the bottom of the prestressed pipe section according to the arrangement position points of the SPMT trucks, each column of the SPMT trucks forming a truck group, and arranging sleepers on the truck group; S3, lifting the prestressed pipe section by the SPMT trucks so that the prestressed pipe section is separated from the fixed buttress; S4, driving the prestressed pipe section by the SPMT trucks from the prefabrication plant to the semi-submersible barge through the wharf; S5, lowering the prestressed pipe section by the SPMT truck support hydraulic cylinder until the prestressed pipe section falls on the on-ship support; S6, continuing to lower the SPMT truck support hydraulic cylinder so that the sleepers do not contact the pipe section; S7, the SPMT trucks return to the wharf, and the prestressed pipe section barge is completed.

6. A method of SPMT truck on barge according to claim 4, wherein, Before step S2, the method further comprises a prefabrication step of the prestressed pipe section: determining the arrangement positions of the four columns of fixed buttresses according to the arrangement position points of the SPMT trucks, so that the four columns of fixed buttresses are arranged in a staggered manner with the arrangement position points and the fixed buttresses distributed in the transverse direction of the prestressed pipe section are arranged symmetrically about the longitudinal center axis of the prestressed pipe section; and then prefabricating the prestressed pipe section so that the two side walls and the two middle walls of the prestressed pipe section are arranged correspondingly on the four columns of fixed buttresses.

7. A method of SPMT truck on barge according to claim 4, wherein, Between steps S2 and S3, the truck group is divided into four zones along the transverse center axis and the longitudinal center axis of the prestressed pipe section, and the hydraulic suspension of all the SPMT trucks in each zone is connected in series through an oil pipe; and the four zones are connected in parallel through an oil pipe. In step S3, the 4-zone vehicle group is staged and synchronously jacked to pre-stress the immersed tube segment; Between steps S3-S4, the vehicle group is divided into three zones, the vehicle group under the front half of the pre-stressed immersed tube segment in the forward direction is one zone, the vehicle group under the rear half of the pre-stressed immersed tube segment in the forward direction is divided into two zones along the longitudinal center axis of the pre-stressed immersed tube segment; the hydraulic suspension of all SPMT vehicles in each zone is connected in series through the oil pipe, and the three zones are connected in parallel through the oil pipe; In step S4, the 3-zone vehicle group supports the pre-stressed immersed tube segment.

8. A method of SPMT truck on barge according to claim 4, characterized by, Before step S4, the semi-submersible barge is docked at the stern and moored to the wharf by cables; then a 40mm-50mm thick steel plate is laid at the joint of the wharf and the semi-submersible barge; then ship-mounted supports are arranged on the deck of the semi-submersible barge; wherein the lateral arrangement position of the ship-mounted supports on the semi-submersible barge is determined according to the arrangement position of the SPMT vehicles.

9. A method of SPMT truck on barge according to claim 8, characterized in that, The ship-mounted supports are arranged in 8 columns on the semi-submersible barge, wherein 4 columns of ship-mounted supports correspond to the two side walls and two middle walls of the pre-stressed immersed tube segment, and the other 4 columns of ship-mounted supports are located between adjacent two columns of SPMT vehicles; the ship-mounted supports distributed in the lateral direction of the semi-submersible barge are symmetrically arranged about the longitudinal center axis of the pre-stressed immersed tube segment.

10. A method of SPMT truck on barge according to any of claims 4-9, characterized in that, In step S4, in the pre-selected operation window, the pre-stressed immersed tube segment is transferred from the wharf to the semi-submersible barge by the SPMT vehicles; During the transfer, the transfer speed is controlled to be within 0.5m / min~1m / min, the ballast of the semi-submersible barge is adjusted, and the height difference between the wharf surface and the stern deck surface and the floating state of the semi-submersible barge are controlled to meet the control requirements of the safety of the SPMT vehicle walking and the stability of the semi-submersible barge.

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