Prestressed shield tunnel and lining member prefabricating method thereof

Abstract

The invention relates to a prestressed shield tunnel and a lining member prefabrication method thereof.The prestressed shield tunnel is formed by splicing a plurality of prestressed shield segments, a hole channel is formed in each prestressed shield segment, each hole channel comprises a pipe body and two hole channel expansion sections located at the end of the corresponding prestressed shield segment, and the pipe bodies are communicated with the hole channel expansion sections; in the prefabrication process of the prestressed shield segment, the pore channel expansion section is a concrete pipeline formed by a pore channel fixing mold used for fixing a pipe body in the concrete pouring process. According to the invention, the end part of the duct is designed into the expansion section, so that the demolding process can be obviously improved, and meanwhile, the penetration process of the prestressed steel bundle in the duct after the duct pieces are assembled into a ring is also improved. And the opening of the expansion section is large, so that the duct fixing mold is more easily separated from the tube sheet. And meanwhile, the pore channel expansion section also provides a wider inlet and outlet for the prestressed steel beam, so that the prestressed steel beam is more easily transited from one duct piece to the pore channel of the next duct piece.

Description

Technical Field

[0001] The invention relates to the technical field of shield tunnels, and in particular to a prestressed shield tunnel and a method for prefabricating lining components thereof. Background Art

[0002] Prestressed shield tunnels usually consist of a series of prefabricated prestressed segments, which are prefabricated in the factory, transported to the construction site, and assembled into the tunnel lining during the advancement of the shield machine.

[0003] Prestressed segments are generally provided with channels. The channels are generally formed during the pouring process using steel pipes, PVC pipes or corrugated pipes. Specifically, before pouring begins, the corrugated pipes are fixed to the formwork using a fixing fixture or bracket to ensure that their position is accurate and stable. The corrugated pipes should be placed along a predetermined path to facilitate the subsequent arrangement of the prestressed steel strands. When pouring concrete begins, a pump truck or other conveying equipment is used to evenly inject concrete into the formwork to ensure that the concrete covers the corrugated pipes and fills every corner of the formwork. During the pouring process, a vibrator is used to vibrate to ensure that the concrete is fully compacted, bubbles are removed, and voids are reduced. After the concrete reaches sufficient strength, demoulding can be carried out. Carefully remove the formwork and check the integrity of the segment and the corrugated pipe. Check whether the corrugated pipe maintains the correct position in the segment without displacement or damage. However, the defects of the above pouring include: the end diameter of the channel remains constant, the same as the diameter of the main part of the channel. This design makes the demoulding process difficult when prefabricating the prestressed segments of prestressed shield tunnels. Since the end of the hole is not expanded, the friction between the mold and the prestressed segment is large, which may require greater force for demolding, which not only increases the difficulty of demolding, but also may cause damage to the prestressed segment. When the hole part of the prestressed segment is damaged, the prestressed segment can only be discarded. Since the segment may be damaged during demolding, this may lead to additional repair work and increase material and labor costs. Frequent use of large force for demolding may accelerate the wear of the mold, requiring more frequent maintenance or replacement of the mold, thereby increasing costs.

[0004] In addition, since the diameter of the end of the tunnel has not expanded, the prestressed steel strands may encounter resistance due to the hole position deviation at the end of the segment when transitioning from one segment to the next. The existence of resistance may lead to uneven distribution of the prestressed steel strands in the tunnel, which will affect the uniform application of prestress, may cause local stress concentration, affect the long-term performance and safety of the structure, and also cause difficulties in the construction operation of the strands in the tunnel. In order to ensure the correct arrangement of the prestressed steel strands, it may take more time to check and adjust the position of the segments, and even need to reassemble the segments, which will greatly increase the difficulty of construction and extend the construction period. During the process of applying prestress, if the prestressed steel strands encounter too much resistance, it may cause the steel strands to break or other unexpected situations, increasing the construction risk. Therefore, the design of keeping the diameter of the end of the tunnel constant not only increases the production cost and construction difficulty, but also may affect the effect of prestressing and the overall performance of the structure.

[0005] For example, patent document CN114991812A discloses a shield tunnel annular prestressed pipe, which includes a hollow corrugated pipe arranged in the annular steel cage of the fixed end segment and the connecting segment, and an annular prestressed steel strand is inserted in the corrugated pipe, and the annular prestressed steel strand is extended after passing through the inner hole of the inner wall of the segment, and the two ends of the prestressed steel strand are respectively connected to the prestressed tendon anchoring device. The prestressed tendon anchoring device includes a trapezoidal shell, and grooves are respectively provided on the two side walls of the trapezoidal shell, wherein the groove on one side wall is connected to the fixed anchor end anchor, and the groove on the other side wall is connected to the tension end anchor. In this invention, the diameter of the hole at the end of the prestressed segment is constant. When prestress is applied to the prestressed pipe ring, the end of the hole of the prestressed segment is easily damaged due to the action of the prestressed steel bundle.

[0006] Therefore, how to improve the prefabrication method of the lining components of the prestressed pipe segment and its prefabrication mold so that the ends of the channels in the prestressed pipe segment are not easily damaged and the resistance to the prestressed steel strands is reduced, while improving the ease of assembly and strand insertion construction in the tunnel, is the current prefabrication problem of the prestressed pipe segment.

[0007] In addition, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the applicant studied a large number of documents and patents when making the present invention, but due to space limitations, not all details and contents are listed in detail. However, this does not mean that the present invention does not have the characteristics of these prior arts. On the contrary, the present invention already has all the characteristics of the prior art, and the applicant reserves the right to add relevant prior art to the background technology. Summary of the invention

[0008] The diameter of the end of the hole remains constant and is the same as the diameter of the main part of the hole. This design makes the demoulding process difficult when prefabricating the prestressed segments of the prestressed shield tunnel. Since the end of the hole is not expanded, the friction between the prestressed segment mold and the prestressed segment is large, resulting in greater force required for demoulding, which not only increases the difficulty of demoulding, but also may cause damage to the prestressed segment. When the hole part of the prestressed segment is damaged, the prestressed segment can only be discarded.

[0009] Therefore, how to improve the channel is not a simple task. If the tube body, such as a bellows, is directly set to a structure with an expanded end, then due to the thin and soft characteristics of the tube body, such as the bellows, the expanded section of the bellows is easily squeezed and deformed by the concrete, and a complete expanded section cannot be formed at all. At the same time, the structure of the bellows in the expanded state also makes it difficult to fix the two ends of the bellows. If the two ends of the bellows are directly plugged with a hollow trumpet-shaped component, the hollow trumpet-shaped plug body will find it difficult to withstand the force exerted by the concrete, and displacement or deformation may occur. Taking a step back, even if the trumpet-shaped plug body is fixed, since the surface of the trumpet-shaped plug body is flush with the end of the pipe segment, the end of the pipe segment and the trumpet-shaped plug body are easily connected and fixed by concrete, and demolding is obviously difficult.

[0010] Therefore, how to improve the pore structure and reduce the difficulty of demoulding at the same time is a technical problem that needs to be solved urgently.

[0011] In view of the deficiencies in the prior art, the present invention provides a prestressed shield tunnel from a first aspect, which is formed by assembling a plurality of prestressed shield segments. A channel is arranged in the prestressed shield segment, and the channel includes a pipe body and at least two channel expansion sections located at the ends of the prestressed shield segment. The pipe body is connected to the channel expansion section. In the prefabrication process of the prestressed shield segment, the channel expansion section is a concrete pipe formed by a channel fixing mold for fixing the pipe body during the pouring of concrete.

[0012] The present invention designs the end of the channel as a trumpet-shaped expansion section, which can significantly improve the demoulding process. The trumpet-shaped expansion section has a large opening, making it easier for the channel fixing mold to be separated from the pipe segment. At the same time, the trumpet-shaped expansion section also provides a more spacious entrance and exit for the prestressed steel bundle, making it easier for the prestressed steel bundle to transition from one pipe segment to the channel of the next pipe segment. This design helps to ensure the smooth arrangement of the prestressed steel bundle, thereby achieving a more uniform prestress distribution and improving the stability and durability of the entire tunnel structure.

[0013] According to a preferred embodiment, the diameter of the expansion section of the channel gradually increases in the direction from the end of the pipe body to the end of the prestressed shield segment, so as to reduce the resistance of the prestressed steel bundles passing through the channel when applying prestress to the assembled prestressed shield segments, and at the same time reduce the difficulty of the crossing construction of the prestressed steel bundles in the channel after the prestressed shield segments are assembled into a ring.

[0014] It is particularly important to note that during the process of applying prestress, there is a slight positional deviation between the ends of two adjacent segments, which increases the friction between the prestressed steel strands and the edges of the protruding segments, thereby increasing the movement resistance. By changing the ends of the tunnel to expansion sections, even if there is a positional deviation between the ends of the two tunnels, the edges of the ends of each prestressed shield segment will not contact the prestressed steel strands and increase the resistance.

[0015] According to a preferred embodiment, the external orifice of the tunnel expansion section is arranged at the end of the prestressed shield segment, and a demolding platform is arranged around the external orifice of the tunnel expansion section. The edge of the demolding platform is inclined relative to the cross-section of the tunnel expansion section to form a demolding angle.

[0016] If the demoulding angle is not set, the end of the prestressed shield segment will be flush with the expansion section mold of the expansion section, and the moving space at the connection between the end of the prestressed shield segment and the mold will be limited. It may take a lot of force to remove the prestressed shield segment from the mold, which not only increases the difficulty of demoulding, but may also cause damage to the prestressed shield segment or the mold.

[0017] After setting the demoulding angle, the end of the prestressed shield segment after shaping can have a larger moving space for demoulding due to the expansion of the demoulding angle. The inclined surface of the demoulding angle provides a larger moving space for the end of the prestressed shield segment after shaping, so that the prestressed shield segment can easily slide out of the mold by slight movement during demoulding. This design not only reduces the force required for demoulding, reduces labor and equipment costs, but also reduces the risk of damage to the prestressed shield segment and mold during demoulding, and improves the safety and efficiency of the demoulding process. In addition, the setting of the demoulding angle also helps to maintain the shape and dimensional accuracy of the prestressed shield segment, ensuring the quality of the final product.

[0018] According to a preferred embodiment, the demoulding angle α of the demoulding platform is in the range of 10 to 75 degrees. The demoulding angle is set in this range, which is conducive to demoulding the prestressed shield segment with a smaller movement range.

[0019] According to a preferred embodiment, the prestressed shield segments include standard segments at anchor ends, standard segments at non-anchor ends, adjacent segments and capping segments, the standard segments at anchor ends are provided with anchoring components, the standard segments at non-anchor ends are provided between two standard segments at anchor ends, the standard segments at anchor ends are connected to adjacent segments, and the adjacent segments are connected to capping segments; wherein, at the end contact portions of adjacent prestressed shield segments, the two channel expansion sections are in a state where the orifices are opposite to each other.

[0020] CN114991812A discloses a shield tunnel annular prestressed pipe, which includes a hollow corrugated pipe arranged in the annular steel cage of the fixed end pipe segment and the connecting pipe segment, and an annular prestressed steel strand is inserted in the corrugated pipe. The annular prestressed steel strand is inserted into the inner layer channel of the inner wall of the pipe segment and then extends out, and the two ends of the prestressed steel strand are respectively connected to the prestressed tendon anchoring device. The prestressed tendon anchoring device includes a trapezoidal shell, and grooves are respectively opened on the two side walls of the trapezoidal shell, wherein the groove on one side wall is connected to the fixed anchoring end anchor, and the groove on the other side wall is connected to the tensioning end anchor. The structural defects of the shield tunnel annular prestressed pipe include: (1) an additional trapezoidal shell is required for the anchoring of the prestressed tendons. (2) The height of the trapezoidal shell protruding from the inner diameter side of the pipe segment is relatively high, which affects the operating limit during the construction of the shield machine, and therefore will be limited in actual construction applications. (3) The trapezoidal shell is set at the bottom of the shield tunnel. In actual construction, after the segments are assembled, tracks need to be laid at the bottom of the tunnel, and transportation equipment for transporting the segments and the excavated materials needs to be set up for transportation. This will conflict with the trapezoidal shell and is inconvenient for actual construction. In addition to the limited working space under the tunnel, there is often water accumulation, waste residue, and waste at the bottom of the tunnel, which affects the operation of threading and tensioning the prestressed steel strands.

[0021] The present invention symmetrically arranges two anchor end standard segments provided with anchor assemblies, so that the stress distribution of the channels in the two anchor assemblies is relatively uniform. By connecting the non-anchor end standard segment, the anchor end standard segment, the adjacent segment and the capping segment to form a prestressed shield tunnel, the overall stability and deformation resistance of the tunnel are effectively improved. The symmetrical arrangement of the anchor assemblies ensures the uniform distribution of channel stress, thereby reducing local stress concentration and enhancing the durability and safety of the tunnel.

[0022] The present invention provides a method for prefabricating lining components of a prestressed shield tunnel from a second aspect, the method comprising: setting a pipe body in a predetermined position on a steel skeleton in a predetermined posture; after placing the steel skeleton in a segment mold, using a channel fixing mold to fix the two ends of the pipe body respectively, and fixing the steel skeleton at the same time; pouring concrete and prefabricating to form a prestressed shield segment; wherein, after the prestressed shield segment is poured with concrete and shaped, the channel comprises a pipe body and at least two channel expansion sections located at the ends of the prestressed shield segment, and the pipe body is connected with the channel expansion section.

[0023] The method for prefabricating lining components of a prestressed shield tunnel of the present invention can form an expanded channel while avoiding the dislocation of the pipe body due to pouring concrete, reduce the passing resistance of the prestressed steel bundle at the channel connection and the friction with the channel edge, reduce the demoulding difficulty of the prestressed shield pipe segment, and at the same time, the force applied by the prestressed steel bundle is more uniform.

[0024] According to a preferred embodiment, the method further includes: the channel fixing mold includes a fixed end mold and an expansion section mold, the fixed end mold is connected to the pipe body, the end of the expansion section mold with a smaller diameter is connected to the fixed end mold, and the concrete is restricted to form the channel expansion section while fixing the end of the pipe body, and the end of the expansion section mold with a larger diameter is bolted by the connecting end in a manner of penetrating the end of the pipe segment mold, thereby fixing the expansion section mold.

[0025] According to a preferred embodiment, the method also includes: setting the channel platform mold between the expansion section mold and the pipe segment mold, so that the expansion section mold presses the channel platform mold, and when the concrete is finalized, the channel platform mold forms a demolding platform around the external orifice of the channel expansion section, and the side of the demolding platform is inclined relative to the cross-section of the channel expansion section to form a demolding angle.

[0026] By installing the demoulding platform, the expansion section mold of the prestressed shield segment is not easily fixed by the concrete. At the same time, the setting of the demoulding angle also increases the moving space of the end of the prestressed shield segment, reducing the difficulty of demoulding.

[0027] According to a preferred embodiment, the channel platform mold is fixed to the segment mold by a connecting end, the channel platform mold is a sheet body with inclined contours on all four surfaces, the inclined surface of the channel platform mold faces the expansion section mold, wherein the angle between the inclined surface of the demolding angle mold and its central axis is the demolding angle. According to a preferred embodiment, the demolding angle angle α of the demolding angle mold has a value range of 10 to 75 degrees. The setting of the demolding angle mold not only allows the end of the expansion section mold to be separated in an orderly manner from the end of the prestressed shield segment, but also positions the expansion section mold to prevent the expansion section mold from shifting. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of a standard segment mold for the anchoring end of a prestressed shield segment provided by the present invention;

[0029] Figure 2 It is a structural schematic diagram of a prestressed shield tunnel provided by the present invention;

[0030] Figure 3 It is a structural schematic diagram of a standard segment at the anchor end of a prestressed shield tunnel provided by the present invention;

[0031] Figure 4It is a schematic diagram of the duct structure of the standard segment at the anchor end of the prestressed shield tunnel provided by the present invention;

[0032] Figure 5 It is a structural schematic diagram of the splicing state of the duct provided by the present invention;

[0033] Figure 6 It is a schematic diagram of the arrangement of the pipe body during the prefabrication process of the lining component provided by the present invention;

[0034] Figure 7 It is a structural schematic diagram of the channel fixing mold provided by the present invention;

[0035] Figure 8 It is a structural schematic diagram of the expansion section mold provided by the present invention;

[0036] Fig. 9 It is a structural schematic diagram of the channel platform mold provided by the present invention;

[0037] Fig.10 is an enlarged schematic diagram of the demoulding angle provided by the present invention;

[0038] Fig.11 It is a schematic diagram of the structure of the non-porous connection end provided by the present invention;

[0039] Fig.12 It is a schematic diagram of the installation of the pipe body of the standard pipe segment mold of the anchor end of the prestressed shield pipe segment provided by the present invention;

[0040] Fig.13 It is a partial schematic diagram of the pipe body installation part of the standard pipe segment mold of the anchor end of the prestressed shield pipe segment provided by the present invention;

[0041] Fig.14 It is a schematic diagram of the axial cross-sectional structure of the anchoring kit of the prestressed shield segment provided by the present invention;

[0042] Fig.15 It is a structural schematic diagram of the indexing ring of the mounting hole of the anchoring kit of the prestressed shield segment provided by the present invention;

[0043] Fig.16 It is a structural schematic diagram of a capping segment of a prestressed shield segment provided by the present invention;

[0044] Fig.17 It is a structural schematic diagram of a pipe orifice mold for an exhaust duct in a capping pipe segment of the present invention;

[0045] Fig.18 It is a structural schematic diagram of a positioning mold for exhaust ducts in a capping pipe segment of the present invention;

[0046] Fig.19 It is a schematic diagram of the inner side surface of the capping segment of the present invention.

[0047] Reference numerals list

[0048] 110: Prestressed shield segment; 111: Standard segment at anchor end; 112: Standard segment at non-anchor end; 113: Adjacent segment; 114: Capping segment; 120: Hole; 121: Hole expansion section; 123: Demolding platform; 130: Anchor kit; 140: Anchor assembly; 141: Groove; 142: Anchor tooth block; 143: Anchoring concrete; 150: Anchor pad; 200: Sealing pad; 300: Prestressed steel strand; 310: Anchor cover; 320: Working clip; 330: Working anchor plate; 340: Spiral reinforcement; 350: Mounting hole indexing ring; 360: Bolt; 370: Grouting hole; 380: Constraint; 400: Standard tube at anchor end Sheet mold; 410: groove mold; 411: anchoring mold; 420: tube body; 421: straight line segment; 422: arc segment; 430: steel bar skeleton; 440: channel fixing mold; 450: fixed end mold; 460: expansion section mold; 480: channel platform mold; 481: connecting end; 482: demoulding angle; 483: connecting hole; 490: non-channel connecting end; 510: exhaust hole; 520: three-way port; 530: exhaust channel; 540: pipe mouth mold; 541: first connecting port; 542: fixing groove; 543: limiting protrusion structure; 544: second connecting port; 550: positioning mold; 551: connecting part; 552: magnetic part. DETAILED DESCRIPTION

[0049] The following is a detailed description with reference to the accompanying drawings.

[0050] In the prior art, when prefabricating prestressed shield segments 110, a pipe body 420 such as a PVC pipe or a corrugated pipe is generally used as a mold of the channel 120 to be fixed in a steel skeleton 430, and the prestressed shield segment 110 is formed by pouring concrete. The diameter of the end of the channel 120 formed in this way remains constant and is the same as the diameter of the main part of the channel. This design makes it difficult to demold the fixed mold used to fix the pipe body 420 and prevent concrete from flowing into the pipe body 420 when prefabricating the prestressed shield segments 110 of the prestressed shield tunnel, that is, the demolding process becomes difficult. The corrugated pipe is the most commonly used pipe body 420 when prefabricating the prestressed shield segments 110. The characteristics of the corrugated pipe are that it is thin and soft. When the corrugated pipe is subjected to the impact of concrete, its end is also more likely to shift, deform and be damaged. Since the end of the bellows is flush with the end of the prestressed shield segment 110, the fixing space of the fixed mold used to fix the end of the bellows is relatively small, and the end of the bellows cannot be well limited. Since the end of the channel is not expanded, the friction between the fixed mold and the prestressed shield segment 110 is large, resulting in that a large force may be required to complete the demolding step during demolding, which not only increases the difficulty of demolding, but also may cause damage to the prestressed shield segment 110. When a part of the channel 120 of the prestressed shield segment 110 is damaged, the prestressed shield segment 110 can only be discarded.

[0051] If the ends of the bellows are simply expanded, the structure of the bellows in the expanded state also makes it difficult to fix the two ends of the bellows. If the two ends of the bellows are directly plugged with a hollow trumpet-shaped component, the hollow trumpet-shaped plug body will be difficult to withstand the force exerted by the concrete, and the hole of the bellows will be over-supported and the ends of the bellows will be broken. Taking a step back, even if the trumpet-shaped plug body is fixed, since the surface of the trumpet-shaped plug body is flush with the end of the prestressed shield segment 110, the end of the prestressed shield segment 110 and the trumpet-shaped plug body are easily connected and fixed by concrete, and demolding is obviously difficult.

[0052] Therefore, how to improve the structure of the channel 120 and reduce the demoulding difficulty is a technical problem that needs to be solved urgently.

[0053] In view of the deficiencies of the prior art, the present invention provides a prestressed shield tunnel. The present invention can also provide a method for prefabricating lining components of a prestressed shield tunnel. The present invention can also provide a prestressed shield segment. The present invention can also provide a casting mold for a prestressed shield segment.

[0054] Example 1

[0055] This embodiment provides a prestressed shield tunnel. Figure 2As shown, the prestressed shield tunnel is formed by assembling a plurality of prestressed shield segments 110. Specifically, a plurality of prestressed shield segments 110 are assembled to form a pipe ring. A plurality of pipe rings are spliced ​​along the tunnel extension direction to form a prestressed shield tunnel. Exemplarily, the outer diameter of the prestressed shield segment 110 is 6000 mm, the ring width is 1200 mm, and the thickness is 300 mm.

[0056] like Figure 2 and Figure 4 As shown, the prestressed shield segment 110 includes an anchor end standard segment 111, a non-anchor end standard segment 112, an adjacent segment 113 and a capping segment 114. The anchor end standard segment 111 is provided with an anchor assembly 140. The non-anchor end standard segment 112 is arranged between two anchor end standard segments 111. The anchor end standard segment 111 is connected to the adjacent segment 113. The adjacent segment 113 is connected to the capping segment 114. A channel 120 is arranged in each prestressed shield segment 110. Preferably, the number of channels 120 of the prestressed shield segment 110 is not less than one. Preferably, the number of channels 120 of the prestressed shield segment 110 is preferably 2 or 4.

[0057] The anchor end standard segment 111, the non-anchor end standard segment 112, the adjacent segment 113 and the capping segment 114 are structurally different. For example, the center angles of the anchor end standard segment 111 and the non-anchor end standard segment 112 are set to 67.3 to 67.5 degrees. The center angle of the adjacent segment 113 is also set to 67.3 to 67.5 degrees. The center angle of the capping segment 114 is set to 22.3 to 22.5 degrees. Figure 2 As shown, the sum of the central angles of the anchor end standard segment 111, the non-anchor end standard segment 112, the adjacent segment 113 and the capping segment 114 is not less than 180 degrees. Such a method of assembling the prestressed shield segment 110 makes the center of gravity of the prestressed shield tunnel deviate from its geometric center and form an eccentricity, so as to reduce the bending moment internal force of the prestressed shield segment 110.

[0058] Such an arrangement causes the center of gravity of the prestressed shield tunnel to deviate from its geometric center, reducing the influence of the internal force of the bending moment on the prestressed shield segment 110, thereby improving the tunnel's ability to resist bending deformation and extending its service life.

[0059] In addition, the bending moment internal force of the prestressed shield segment 110 can be effectively reduced by adjusting its eccentricity, which can significantly reduce the amount of steel reinforcement of the prestressed shield segment 110 and reduce the project cost. The weight is reduced from about 1 ton per ring to 600 kg per ring, and the steel fiber concrete prestressed shield segment 110 is further reduced to 300 kg per ring.

[0060] like Figure 2As shown, an anchoring assembly 140 is prefabricated on the standard segment 111 at the anchoring end, and the cross-sections of the two ends are parallel to the central axis of the pipe ring. Anchoring assemblies 140 are not provided on the standard segment 112 at the non-anchoring end, and the cross-sections of the two ends are parallel to the central axis of the pipe ring. Anchoring assemblies 140 are not provided on the capping segment 114, and the cross-sections of the two ends are inclined toward each other. The structure of the adjacent segment 113 matches the structure of the capping segment 114. The cross-section of the first end of the adjacent segment 113 is parallel to the central axis of the pipe ring, which enables the adjacent segment 113 to be assembled with the standard segment 111 at the anchoring end. The cross-section of the second end of the adjacent segment 113 is relatively inclined to the central axis of the pipe ring, and the inclination angle is the same as the inclination angle of the cross-section of the end of the capping segment 114, which enables the adjacent segment 113 to be assembled with the capping segment 114.

[0061] The capping segment 114 is a part of the last prestressed shield segment to be assembled. The cross-sections of the two ends of the capping segment 114 are set to be structures inclined toward each other, which reduces the difficulty of capping the pipe ring. Specifically, when the two ends of the capping segment 114 are relatively inclined, a wide end and a narrow end of the capping segment 114 will be formed in the direction of the central axis. The narrow end of the capping segment 114 is first placed between the two adjacent pipe segments 113, and the wide end of the capping segment 114 is pushed axially, so that the capping segment 114 gradually applies force to the adjacent pipe segment 113 and pushes the adjacent pipe segment 113 to move, so that the capping segment 114 is easier to insert and form a pipe ring tightly connected to each other with other prestressed shield segments 110.

[0062] like Figure 5 As shown, when a plurality of prestressed shield segments 110 are assembled to form a pipe ring, the channels 120 in the prestressed shield segments 110 are also assembled to form a complete circular channel. Exemplarily, the dimensions of the non-expanded section of the channel 120 include: an inner diameter of 56 mm and an outer diameter of 60 mm. The prestressed steel strand 300 passes through the circular channel 120 and is tensioned in the anchor assembly 140, so that the prestressed steel strand 300 applies prestress to each prestressed shield segment 110.

[0063] like Figure 2 As shown, the anchor end standard segments 111 are symmetrically distributed on both sides of the pipe ring. Correspondingly, in the case of two channels 120, the two prestressed steel strands 300 are tensioned and fixed on different anchoring assemblies 140, that is, the two prestressed steel strands 300 are tensioned in a staggered manner. When there are three or four channels 120, each prestressed steel strand 300 is also tensioned in a staggered manner on a non-adjacent anchoring assemblies 140.

[0064] The standard segments 111 at the anchoring end are symmetrically distributed, so that the stress distribution of the duct 120 in the two anchoring assemblies 140 is relatively uniform. By connecting the non-anchoring end standard segments 112, the anchoring end standard segments 111, the adjacent segments 113 and the capping segments 114 to form a prestressed shield tunnel, this structural design effectively improves the overall stability and deformation resistance of the tunnel. The symmetrical arrangement of the anchoring assemblies 140 ensures the uniform distribution of stress in the duct, thereby reducing local stress concentration and enhancing the durability and safety of the tunnel.

[0065] Preferably, the annular prestressed structure anchor assembly 140 is set in two, located at the four o'clock and eight o'clock directions at the bottom of the tunnel structure. The main advantage is that when the prestressed shield segments 110 are spliced ​​into a ring, they will not be affected by the limited working space at the bottom of the tunnel, will not affect the normal shield construction, will not be affected by adverse factors such as tunnel seepage and screw machine slag spraying accumulated at the bottom of the tunnel, and will not affect the prestressed cable threading and tensioning operations. In addition, from the perspective of force, only a single anchor assembly 140 is set at the bottom of the tunnel, and the prestressed anchor is in the same section. After prestressing, the diagonal stress loss of the anchor tooth block 142 is the largest, and the channel stress loss distribution of the two channels 120 of the anchor tooth block 142 is the same, and the structural force is unfavorable. If two anchor tooth blocks 142 are set separately, the maximum stress loss point is not in the same position, so that the stress distribution in the tunnel is relatively uniform and the structure is more reasonable.

[0066] Figure 3 The structure of the anchor end standard segment 111 is shown. Figure 4 FIG. 1 shows a perspective view of a standard segment 111 at an anchor end. Figure 3 and Figure 4 As shown, the anchoring assembly 140 includes a groove 141 and an anchoring tooth block 142. The anchoring tooth block 142 constitutes a part of the channel of the channel 120, and the groove 141 is arranged from the side of the anchoring tooth block 142, and the extension direction of the groove 141 is perpendicular to the central axis.

[0067] like Figure 3 and Figure 4 As shown, the curved profile of the groove 141 includes a straight line segment 421 and an arc segment 422. The straight line segment 421 of the groove 141 is adjacent to the anchor tooth block 142 to form a space for tensioning the prestressed steel strand 300. The arc segment 422 of the groove 141 transitions naturally with the straight line segment 421. Such a design not only improves the reliability of the anchor assembly 140, but also provides a more convenient tensioning operation space, ensuring that the prestressed steel strand 300 can smoothly apply prestress during the tensioning process.

[0068] like Figure 3 and Figure 4As shown, in the anchor assembly 140, the tension end of the prestressed steel strand 300 is fixed by the anchor kit 130. The anchor kit 130 is arranged on the anchoring concrete 143, so that the groove 141, the anchoring tooth block 142 and the anchoring concrete 143 together form a force-bearing structure. This ensures that the tension force of the prestressed steel strand 300 can be effectively transmitted to the prestressed shield segment 110, thereby improving the overall stability and tensile performance of the structure.

[0069] The anchoring assembly 140 protruding on the inner diameter side of the anchoring end standard pipe segment 111 can be provided with a flat tensioning end anchoring kit 130 to anchor the prestressed steel strand 300, which can save anchoring space.

[0070] According to a preferred embodiment, the central angle of the anchor tooth block 142 in the circumferential direction is not less than one quarter of the central angle of the standard segment 111 at the anchor end. This allows the anchor tooth block 142 to have sufficient contact area and force area in the prestressed shield segment 110, thereby enhancing the pull-out resistance and stability of the anchor assembly 140. Exemplarily, the height of the anchor tooth block 142 is 180 mm, the central angle is 20°, and the inner arc length is 901 mm. The depth of the groove 141 is set to 60 mm.

[0071] As shown above, the provision of the groove 141 can reduce the impact of the anchoring tooth block 142 on the tunnel construction limit, facilitate the assembly construction of the prestressed shield segment 110, and at the same time ensure that there is a certain thickness of the protective layer from the outer skin of the embedded steel pipe. The size of the anchoring tooth block 142 meets the requirements of the assembly robot operation. The channel 120 at the anchoring tooth block 142 is staggered. In addition to ensuring the smooth progress of the prestressed tendon tensioning process, the bending degree of the channel 120 should be minimized to reduce the friction loss of the channel 120.

[0072] A further obvious difference from the prior art is that in the present invention, the channel 120 includes a pipe body 420 and two channel expansion sections 121 located at the ends of the prestressed shield segment 110 . Figure 4 and Figure 5 The expansion section 121 of the hole 120 is shown as an example. In the prefabrication process of the prestressed shield segment 110, the expansion section 121 is a concrete pipe formed by the hole fixing mold 440 for fixing the pipe body 420 during the pouring of concrete. The expansion sections 121 are also provided at both ends of the hole 120 in the non-anchored end standard segment 112, the adjacent segment 113 and the capping segment 114. Due to the similar structure, the present invention is based on Figure 4 Explain to the representatives.

[0073] Figure 5The figure shows the state of two adjacent channel expansion sections 121 when two prestressed shield segments 110 are assembled together. At the ends of adjacent prestressed shield segments 110, especially at the contacting parts of the ends of adjacent prestressed shield segments, the two channel expansion sections 121 are in a state of facing each other.

[0074] Specifically, the diameter of the duct expansion section 121 gradually increases from the end of the tube body 420. The expansion directions of the duct expansion sections 121 at both ends of the tube body 420 are opposite. Figure 5 As shown, if there is misalignment (deviation) between adjacent prestressed shield segments 110, since the prestressed steel bundle 300 passes through the center of the two channel expansion sections 121 and does not contact the edge of the channel expansion section 121, the misalignment of adjacent prestressed shield segments 110 has little effect on the cable threading process of adjacent prestressed shield segments 110, or even no effect, ensuring smooth assembly of the prestressed shield segments 110. This also reduces the friction and loss of the prestressed steel bundle 300 during the cable threading process, ensuring the effective application of prestress.

[0075] In contrast, in the prior art, since the dimensions of both ends of the tube body 420 are not expanded, when adjacent prestressed shield segments 110 are misaligned, the edge of the end of the protruding channel 120 easily hinders the threading process of the prestressed steel bundle 300, thereby increasing the threading resistance between the prestressed steel bundle 300 and the end edge of the channel 120.

[0076] like Figure 7 As shown, the external opening of the tunnel expansion section 121 is arranged at the end of the prestressed shield segment 110. A demoulding platform 123 is arranged around the external opening of the tunnel expansion section 121. The edge of the demoulding platform 123 is inclined relative to the cross section of the tunnel expansion section 121 and forms a demoulding angle 482. The angle of the demoulding angle 482 is α. Fig. 9 and Fig.10 As shown, the demoulding angle 482 of the demoulding platform 123 has a value range of 10 to 75 degrees. Further preferably, the value range of the demoulding angle 482 is 15 to 65 degrees. Further preferably, the value range of the demoulding angle 482 is 20 degrees.

[0077] If the demolding angle 482 is not set, the end of the prestressed shield segment 110 will be flush with the expansion segment mold 460 of the expansion segment, and the moving space at the connection between the end of the prestressed shield segment 110 and the expansion segment mold 460 will be limited. It may take a large force to separate the prestressed shield segment 110 from the expansion segment mold 460, which not only increases the difficulty of demolding, but may also cause damage to the prestressed shield segment 110 or the expansion segment mold 460.

[0078] After the demoulding angle 482 is set, since the demoulding angle 482 is in an expanded state, the end of the prestressed shield segment 110 after shaping can have a larger moving space for demoulding. The bevel of the demoulding angle 482 provides a larger moving space for the end of the prestressed shield segment 110 after shaping, so that the prestressed shield segment 110 can easily slide out of the expansion section mold 460 by slightly moving during demoulding. This design not only reduces the force required for demoulding, reduces labor and equipment costs, but also reduces the risk of damage to the prestressed shield segment 110 and the expansion section mold 460 during the demoulding process, and improves the safety and efficiency of the demoulding process. In addition, the setting of the demoulding angle 482 also helps to maintain the shape and dimensional accuracy of the prestressed shield segment 110, ensuring the quality of the final product.

[0079] For example, the length of the expansion section 121 along the circumferential direction of the prestressed shield segment 110 is 75 mm, and the expansion value is 75 mm. For example, four φ15.6mm-1860MPa prestressed steel strands 300 are used in each channel 120, and the tension is controlled to be 1320MPa. The cross-sectional area of ​​the single prestressed steel strand 300 is about 560mm. 2 .

[0080] According to a preferred embodiment, at least two groups of prestressed steel strands 300 pass through different channels 120, and the ends of the two groups of prestressed steel strands 300 are fixed in different anchoring assemblies 140 in a staggered manner to reduce the friction loss of the channel 120. This design effectively reduces the friction loss in the channel 120, ensures the effective transmission of prestress, thereby improving the prestress effect of the entire structure and enhancing the bearing capacity of the shield tunnel.

[0081] Preferably, if Figure 5 As shown, the demoulding platform 123 is also a waterproof groove with a length of 113 mm. In the present invention, at least one sealing gasket can be arranged in the waterproof groove. The annular waterproof sealing gasket is made of water-swellable rubber material. For example, the outer diameter of the sealing gasket is 111 mm, the inner diameter is 91 mm, and the ring width is 6 mm. In addition to playing a waterproof role, the sealing gasket can also prevent the leakage of the working slurry when the channel 120 is subsequently poured with concrete.

[0082] Preferably, the tensioning end of the prestressed steel strand 300 is fixed by an anchoring kit 130 such as an anchor pad 150. Fig.14 As shown, the structure inside the anchor kit 130 may include an anchor plate 150 and a spiral rib 340 .

[0083] Specifically, the prestressed steel strand 300 passes through the constraint 380 and extends out of the anchor tooth block 142. The constraint 380 is a cylindrical structure and is provided with a plurality of channels that allow the prestressed steel strand 300 to pass through. The constraint 380 passes through the side wall of the anchor tooth block 142. Inside the anchor tooth block 142, the outer periphery of the constraint 380 is sleeved with an anchor pad 150. The anchor pad 150 is fastened to the outer side of the constraint 380 by the spiral rib 340 in a sleeved manner. Outside the anchor tooth block 142, a working clip 320 and a working anchor plate 330 are provided in the channel opening of the constraint 380. The working anchor plate 330 is used to squeeze the prestressed steel strand 300 in the channel. The working clip 320 is inserted between the prestressed steel strand 300 and the working anchor plate 330, further reducing the gap around the prestressed steel strand 300, so that the prestressed steel strand 300 can only be tensioned in one direction. Preferably, the cross-section of the working clamp 320 is triangular. When the prestressed steel strand 300 is subjected to an inward force, the pressure between the working clamp 320 and the prestressed steel strand 300 increases, so that the inward movement trend of the prestressed steel strand 300 is subjected to greater resistance.

[0084] Preferably, Fig.14 and Fig.15 As shown, the anchor cover 310 can be connected to the anchor pad 150 and fixed to the side wall of the anchor tooth block 142 by a mechanical fixing assembly such as bolts. A sealing pad 200 can also be provided between the anchor cover 310 and the side wall of the anchor tooth block 142 to achieve waterproofing. The anchor cover 310 provides additional protection to prevent environmental factors from affecting the prestressed steel tendon 300, thereby improving the durability and stability of the entire prestressed system.

[0085] like Fig.15 As shown, illustratively, there are four channels in the restraining member 380 for restraining the prestressed steel strand 300. In the anchor cover 310, there is also a mounting hole indexing ring 350. The mounting hole indexing ring 350 is used to provide an installation indication position for the mounting hole to achieve accurate positioning. Exemplarily, four bolt holes are provided on the mounting hole indexing ring 350 for installing bolts 360. Preferably, a grouting hole 370 is also provided on the mounting hole indexing ring 350. The grouting hole 370 is connected to the duct 120. The grouting hole 370 is used to inject slurry into the duct 120.

[0086] Preferably, the junction between the anchor plate 150 and the duct 120 needs to be sealed with a heat shrink tube or wrapping tape to prevent the slurry from penetrating into the pipe during prefabrication. The spiral rib 340 is provided with 4 turns. A G3 / 4 grouting hole is provided on the anchor plate 150.

[0087] Example 2

[0088] This embodiment is a further improvement on Embodiment 1, and the repeated contents will not be repeated here.

[0089] In this embodiment, the segment mold for capping the segment 114 is improved.

[0090] like Fig.16 As shown, the structure of the capping segment 114 of the present invention is different from the structure of the common capping segment in the prior art.

[0091] like Fig.16 As shown, the capping segment 114 of the present invention is located at the top of the shield tunnel, and the channel 120 inside it is different from other segments. The channel 120 inside the capping segment 114 is provided with a three-way port 520. There is an exhaust channel 530 between the three-way port 520 and the inner wall of the capping segment 114. The opening of the exhaust channel 530 on the inner wall of the capping segment 114 is an exhaust hole 510. Preferably, a valve-like device can also be provided on the exhaust hole 510.

[0092] The advantage of the present invention of providing the exhaust channel 530 and the exhaust hole 510 inside the capping segment 114 is that when the slurry is injected into the channel 120, the exhaust hole 510 is in an open state. The slurry is injected from the anchor kit 130. When the slurry in the channel 120 is filled, the gas in the channel 120 can be discharged from the exhaust hole 510 through the exhaust channel 530, thereby reducing the filling resistance of the slurry in the channel 120 and also avoiding the formation of more bubbles inside the slurry. The channel 120 prefabricated in this way has a high density of the slurry inside and better firmness.

[0093] In the present invention, the exhaust channel 530 and the exhaust hole 510 are prefabricated by using an exhaust channel mold. The exhaust channel mold includes a pipe mouth mold 540, an exhaust pipe body mold (not shown in the figure) and a positioning mold 550.

[0094] The exhaust pipe body mold is a tube. Since the shape of the exhaust pipe body can be set arbitrarily without restriction, there are many optional materials for the exhaust pipe body mold. The present invention preferably uses plastic tubes, rubber tubes, etc. with lower costs as the exhaust pipe body mold.

[0095] When installing the tube segment mold of the capping tube segment 114, at least one opening can be set at any position on the tube body 420 installed inside the tube segment mold. When there are two tube bodies 420, each tube body 420 is provided with at least one opening. The opening can protrude slightly from the surface of the tube body 420 so that there is a position to fix the exhaust pipe body mold. Fix one end of the exhaust pipe body mold to the opening. There are many fixing methods, which can be fixed by colloid or mechanical fixing methods such as bolt fixing, as long as the effect of fixing one end of the exhaust pipe body mold and preventing it from moving is achieved. After one end of the exhaust pipe body mold is fixed to the opening of the tube body 420, a three-way port 520 is formed at the opening.

[0096] Preferably, if Fig.17As shown, the nozzle mold 540 is a pipe body connected at both ends. The nozzle mold 540 can be made of metal or plastic. The nozzle mold 540 includes a first connection port 541 and a second connection port 544. The outer wall of the first connection port 541 is provided with a fixing groove 542 for fixing the connecting end of the exhaust pipe body mold. The fixing groove 542 is a concave groove body. When the connecting end of the exhaust pipe body mold is fixed in the fixing groove 542 using a fixing member (such as a clamp), the first connection port 541 forms a step structure relative to the fixing groove 542. The step structure can hinder the movement of the fixing member, thereby preventing the connecting end of the exhaust pipe body mold from falling off from the first connection port 541 when concrete is poured.

[0097] A limiting protrusion structure 543 is provided in the middle of the nozzle mold 540. The cross-sectional profile of the limiting protrusion structure 543 is a polygonal structure, so it has edges and corners. The limiting protrusion structure 543 protrudes from a part of the surface of the nozzle mold 540 and forms an obvious polygonal ring. The limiting protrusion structure 543 is used to limit the rotation of the nozzle mold 540.

[0098] When the concrete is hardened and the capping segment 114 is formed, the positioning mold 550 needs to be unscrewed (rotated and twisted out) from the second interface 544. During the unscrewing process, if the limiting protrusion structure 543 is not provided, the nozzle mold 540 will be driven by the positioning mold 550 and rotate together in the hardened concrete, and the positioning mold 550 cannot be taken out. The limiting protrusion structure 543 is designed to have a protrusion or an angular structure. The protrusion or angular structure can limit the rotation of the nozzle mold 540, so that the positioning mold 550 and the nozzle mold 540 can rotate relative to each other, thereby facilitating the positioning mold 550 to be unscrewed from the second interface 544.

[0099] The outer diameter of the first connection port 541 of the nozzle mold 540 is smaller than the outer diameter of the second connection port 544. Fig.17 As shown, the second connection port 544 is obviously thicker than the first connection port 541. Further preferably, the inner diameters of the second connection port 544 and the first connection port 541 may be the same or different.

[0100] The second connection port 544 is used to be connected to the positioning mold 550 in a detachable manner. Fig.18 As shown, the positioning mold 550 includes a connecting portion 551 and a magnetic portion 552. The connecting portion 551 and the magnetic portion 552 are integrally arranged. A threaded structure is arranged on the outer diameter of the connecting portion 551, which is used to be threadedly connected with the second connecting port 544 of the nozzle mold 540 to achieve a detachable connection.

[0101] The magnetic part 552 is made of magnetic material, especially strong magnetic material. The magnetic part 552 is used to be adsorbed on the bottom (metal material) of the segment mold of the capping segment 114, and is used to limit the outlet position of the exhaust duct, that is, to limit the position of the nozzle mold 540, so as to prevent the nozzle mold 540 from tipping, tilting and displacement under the impact of concrete.

[0102] In the prior art, since the segment mold of the capping segment 114 cannot be destroyed, the exhaust duct cannot be set, which makes the slurry in the duct 120 injected slowly and easily have bubbles, and the density is low. The present invention improves the positioning mold 550 with strong magnetism to position the exhaust hole 510 at the bottom of the segment mold of the capping segment 114, and after the capping segment 114 is prefabricated (that is, after the concrete is set), the positioning mold 550 can be removed for repeated use.

[0103] The advantages of the exhaust duct mold of the present invention are that the exhaust duct mold is easy to install and disassemble, simple to set up, and the positioning mold 550 can be reused. The advantages of the present invention are particularly that the exhaust duct 530 is prefabricated without destroying the segment mold of the capping segment 114, the difficulty of slurry entering the duct 120 is reduced, and the density of the duct 120 is improved after the concrete solidifies.

[0104] Therefore, after one end of the exhaust pipe body mold is connected to the pipe body 420, the other end of the exhaust pipe body mold is connected to the first connection port 541 of the nozzle mold 540. The second connection port 542 of the nozzle mold 540 is threadedly connected to the connection portion 551 of the positioning mold 550. The nozzle mold 540 is magnetically positioned at a designated position at the bottom of the segment mold of the capping segment 114 by the magnetic portion 552 of the positioning mold 550. When the poured concrete is finalized, the positioning mold 550 appears on the surface of the inner wall of the capping segment 114. The positioning mold 550 is separated from the nozzle mold 540 in a rotating manner, and the exhaust hole 510 formed by the nozzle mold 540 appears.

[0105] like Fig.19 As shown, the structure of the inner wall of the capping tube segment 114 is shown. Two exhaust holes 510 are provided on the capping tube segment 114. Preferably, Fig.19 The two exhaust holes 510 are symmetrically arranged. In the production process of actual products, the multiple exhaust holes 510 can also be asymmetrically arranged.

[0106] Example 3

[0107] This embodiment is a further improvement of Embodiment 1 and Embodiment 2, and the repeated contents will not be repeated here.

[0108] This embodiment provides a method for prefabricating lining components of a prestressed shield tunnel, the method comprising:

[0109] S1: Figure 6 As shown, the tube body 420 is arranged at a predetermined position of the steel frame 430 in a predetermined posture.

[0110] S2: Figure 6 As shown, after the steel skeleton 430 is placed into the pipe segment mold, the two ends of the pipe body 420 are fixed respectively using the channel fixing mold 440, and the steel skeleton 430 is fixed at the same time.

[0111] Here, the segment mold is a general term, including the segment mold of the anchor end standard segment 400, the segment mold of the non-anchor end standard segment 112, the segment mold of the adjacent segment 113, and the segment mold of the capping segment 114. The structure of the segment mold of the non-anchor end standard segment 112, the segment mold of the adjacent segment 113, and the segment mold of the capping segment 114 is not shown in the figure. The present invention uses the anchor end standard segment mold 400 as a representative to display the segment mold.

[0112] When the concrete is set, an anchor assembly 140 will be formed on the inner surface of the prestressed shield segment 110 .

[0113] The present invention specifically describes the structure inside the anchor end standard segment mold 400.

[0114] like Fig.12 and Fig.13 As shown, an anchoring mold 411 and a groove mold 410 corresponding to the anchoring assembly 140 are provided in the anchoring end standard segment mold 400. The anchoring mold 411 forms a groove structure on the bottom surface of the anchoring end standard segment mold 400. The groove mold 410 protrudes on both sides of the anchoring mold 411, and is configured such that its protruding structure includes a straight segment part and an arc segment part. The straight segment part and the arc segment part are transitionally connected.

[0115] Three tube bodies 420 are fixed in the anchor end standard segment mold 400. The two ends of a tube body 420 are respectively fixed to the two ends of the anchor end standard segment mold 400 by a channel fixing mold 440. When the concrete is set, this tube body 420 will form a channel 120 with a channel expansion section 121 at both ends.

[0116] The other two tube bodies 420 are arranged in relation to the anchoring mold 411, and their ends are not all directly fixed by the channel fixing mold 440. Fig.12 and Fig.13 As shown, two tube bodies 420 are arranged crosswise above the anchoring mold 411. One end of the tube body 420 is fixed to the end of the anchoring end standard segment mold 400 by the channel fixing mold 440, and the other end is fixed to a side wall of the anchoring mold 411 by the anchoring kit 130.

[0117] For example, in Fig.12 and Fig.13 In the figure, for the shorter tube body 420 on the left, its left end is fixed to the left end of the anchor end standard segment mold 400 by the channel fixing mold 440, and its right end is fixed to the right side wall of the anchor mold 411 by the anchor kit 130. For the shorter tube body 420 on the right, its right end is fixed to the right end of the anchor end standard segment mold 400 by the channel fixing mold 440, and its left end is fixed to the left side wall of the anchor mold 411 by the anchor kit 130. Here, left and right refer to Fig.12 and Fig.13 The left and right directions are only used for exemplary direction description and are not used to limit the structural direction of the present invention.

[0118] Here, the present invention uses the anchor kit 130 to directly fix the end of the pipe body 420, which has the following advantages: (1) The anchor kit 130 is fixed inside the anchor assembly 140, saving the external space of the standard pipe segment 111 at the anchor end, and further expanding the space inside the completed shield tunnel.

[0119] For example, when the prestressed steel strand 300 is inserted into the hole 120 and tensioned, the exterior of the anchor assembly 140 is a flat integral structure, and its side wall does not expose a portion of the anchor kit 130, thereby reducing installation hazards and obstacles to other installation work.

[0120] (2) The anchoring kit 130 is fixed inside the anchoring assembly 140 , so construction workers have more operating space when tensioning the prestressed steel strand 300 in the groove 141 , and the difficulty is reduced.

[0121] (3) The use of the channel fixing mold 440 is reduced, and some steps of disassembling and assembling the channel fixing mold 440 are also reduced, simplifying the construction procedure.

[0122] S3: pouring concrete and prefabricating prestressed shield segments 110.

[0123] After the prestressed shield segment 110 is poured with concrete and shaped, the channel 120 includes a pipe body 420 and two channel expansion sections 121 located at the ends of the prestressed shield segment 110. The pipe body 420 and the channel expansion section 121 are connected.

[0124] The method for prefabricating lining components of the prestressed shield tunnel can form an expansion-shaped channel while avoiding the dislocation of the pipe body 420 due to the pouring of concrete, reduce the resistance of the prestressed steel bundle 300 when passing through the connection of the channel 120 and the friction with the edge of the channel 120, and reduce the difficulty of demoulding the prestressed shield segment 110. At the same time, the force applied by the prestressed steel bundle 300 to the prestressed shield segment 110 is more uniform.

[0125] like Figure 7 As shown, the channel fixed mold 440 includes a fixed end mold 450 and an expansion section mold 460. The fixed end mold 450 and the expansion section mold 460 can be connected in an integral manner or in a split manner. The fixed end mold 450 is connected to the pipe body 420. The fixed end mold 450 is connected to the expansion section mold 460. The smaller diameter end of the expansion section mold 460 is connected to the fixed end mold 450. The expansion section mold 460 restricts the concrete from forming the channel expansion section 121 while fixing the end of the pipe body 420. The larger diameter end of the expansion section mold 460 is bolted by the connecting end 481 in a manner that penetrates the end of the pipe segment mold to fix the expansion section mold 460.

[0126] Preferably, the channel platform mold 480 is connected to the expansion section mold 460 to fix the expansion section mold 460. Specifically, a connection hole 483 is provided in the center of the channel platform mold 480. After the end of the pipe body 420 is connected in sequence by the fixed end mold 450, the expansion section mold 460 and the channel platform mold 480, the connection end 481 passes through the through hole on the anchor end standard segment mold 400 in a bolted manner and is connected to the expansion section mold 460. The connection end 481 is preferably a bolt.

[0127] Preferably, the fixed end mold 450 is connected to the tube body 420. The expansion section mold 460 is fixed between the fixed end mold 450 and the channel platform mold 480. In this way, the end of the tube body 420 is fixed and protected, and is not easily deformed. The expansion section mold 460 also prevents the slurry from flowing into the tube body 420 when forming the expansion section profile.

[0128] When the concrete is set, after removing the fixed end mold 450, the expansion section mold 460 and the channel platform mold 480, the space around the external opening of the channel expansion section 121 occupied by the channel platform mold 480 forms a demoulding platform 123. The edge of the demoulding platform 123 is inclined relative to the cross section of the channel expansion section 121 and forms a demoulding angle 482.

[0129] The channel fixing mold 440 and the channel platform mold 480 of the present invention can fix the pipe body 420 and also shape the channel expansion section 121 in concrete. The installation of the demoulding platform 123 makes it difficult for the expansion section mold 460 of the prestressed shield segment 110 to be fixed by concrete. At the same time, the setting of the demoulding angle 482 also increases the moving space of the end of the prestressed shield segment 110, and reduces the demoulding difficulty.

[0130] During the construction process, if Figure 7 and Figure 8As shown, preferably, the fixed end mold 450 is inserted into the inner diameter of the end of the tube body 420 and connected, and the expansion section mold 460 is connected to the demoulding platform 123. At this time, if the fixed end mold 450 and the expansion section mold 460 are separate structures, a step of connecting the two is required. If the fixed end mold 450 and the expansion section mold 460 are connected in an integrated manner, the expansion section mold 460 is directly connected to the demoulding platform 123.

[0131] Such a configuration allows the end of the tube body 420 to be fixed and protected at the same time, and is not easily deformed. The expansion section mold 460 is a cone structure, and its diameter gradually increases from the top of the cone. The expansion section mold 460 is gradually connected tightly to the end of the tube body 420, and the joint gap between the two can be sealed by filling with sealing materials, wrapping with tape, installing sealing rubber rings, etc. The expansion section mold 460 also prevents concrete from flowing into the tube body 420 when forming the expansion section contour.

[0132] like Fig. 9 As shown, the channel platform mold 480 is fixed on the pipe segment mold by the connecting end 481. The channel platform mold 480 is a sheet body with an inclined surface. The inclined surface of the channel platform mold 480 faces the expansion section mold 460.

[0133] The angle between the inclined surface of the channel platform mold 480 and its central axis is the demoulding angle 482.

[0134] like Fig.10 As shown, the value range of the demoulding angle 482 of the channel platform mold 480 is 10 to 75 degrees. The demoulding angle 482 is preferably 20 degrees.

[0135] The provision of the channel platform mold 480 not only allows the end of the expansion section mold 460 to be separated from the end of the prestressed shield segment 110 in an orderly manner, but also positions the expansion section mold 460 to prevent the expansion section mold 460 from shifting.

[0136] like Fig.11 As shown, when the channel 120 is not provided in the prestressed shield segment 110, the hole in the segment mold corresponding to the position of the channel 120 is blocked by the non-channel connection end 490, so that concrete cannot flow out of the segment mold, and the end of the segment mold is kept free of holes and smooth for producing non-prestressed segments.

[0137] The axial edge of the non-channel connection end 490 is parallel to the axial direction and is not inclined. Since there is no mold inside the prestressed shield segment 110 that does not contain the channel 120 and needs to be separated, the non-channel connection end 490 does not need to be set with a demolding angle 482. The non-channel connection end 490 blocks the end holes of the segment mold, making the end of the segment mold a flat and smooth plane without pits or holes, and no platform is formed. Here, the connection end 481 passes through the through hole on the segment mold in a bolt-fixed manner, and is connected to the non-channel connection end 490, so that the non-channel connection end 490 blocks the holes at the end of the segment mold to prevent concrete from flowing out of the holes. The connection end 481 is preferably a bolt.

[0138] It should be noted that the above-mentioned specific embodiments are exemplary, and those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also belong to the disclosure scope of the present invention and fall within the protection scope of the present invention. Those skilled in the art should understand that the present invention specification and its drawings are illustrative and do not constitute limitations on the claims. The scope of protection of the present invention is defined by the claims and their equivalents. The present invention specification contains multiple inventive concepts, such as "preferably" or "according to a preferred embodiment", which means that the corresponding paragraph discloses an independent concept, and the applicant reserves the right to file a divisional application based on each inventive concept.

Claims

1. A prestressed shield tunnel, formed by assembling a plurality of prestressed shield segments (110), wherein a hole (120) is provided in each of the prestressed shield segments (110), characterized in that: The duct (120) comprises a pipe body (420) and two duct expansion sections (121) located at the ends of the prestressed shield segment (110), the pipe body (420) and the duct expansion sections (121) are connected, wherein: During the prefabrication process of the prestressed shield segment (110), the channel expansion section (121) is a concrete pipe formed by a channel fixing mold (440) for fixing the pipe body (420) during the concrete pouring process.

2. The prestressed shield tunnel according to claim 1, characterized in that: In the direction from the end of the tube body (420) to the end of the prestressed shield segment (110), the diameter of the hole expansion section (121) gradually increases to reduce the resistance of the prestressed steel bundle (300) passing through the hole (120) when applying prestress to the assembled prestressed shield segment (110).

3. The prestressed shield tunnel according to claim 1 or 2, characterized in that: The external opening of the hole expansion section (121) is arranged at the end of the prestressed shield segment (110). A demoulding platform (123) is arranged around the external opening of the channel expansion section (121), and the edge of the demoulding platform (123) is inclined relative to the cross section of the channel expansion section (121) to form a demoulding angle (482).

4. The prestressed shield tunnel according to any one of claims 1 to 3, characterized in that: The demoulding angle (482) of the demoulding platform (123) has a value range of 10 to 75 degrees.

5. The prestressed shield tunnel according to any one of claims 1 to 4, characterized in that: The prestressed shield segment (110) comprises an anchor end standard segment (111), a non-anchor end standard segment (112), an adjacent segment (113) and a capping segment (114). The anchor end standard segment (111) is provided with an anchor assembly (140). The non-anchor end standard segment (112) is arranged between the two anchor end standard segments (111). The anchoring end standard pipe segment (111) is connected to the adjacent pipe segment (113), and the adjacent pipe segment (113) is connected to the capping pipe segment (114); Wherein, at the end contact portion of the adjacent prestressed shield segments (110), the two channel expansion sections (121) are in a state where the openings are facing each other.

6. A method for prefabricating lining components of a prestressed shield tunnel, characterized in that: The method comprises: arranging the tube body (420) at a predetermined position of the steel frame (430) in a predetermined posture; After the steel bar skeleton (430) is placed in the pipe segment mold, a channel fixing mold (440) is used to fix the two ends of the pipe body (420) respectively, and the steel bar skeleton (430) is fixed at the same time; Pouring concrete and prefabricating the prestressed shield segment (110); After the prestressed shield segment (110) is poured with concrete and shaped, the channel (120) comprises a tube body (420) and at least two channel expansion sections (121) located at the ends of the prestressed shield segment (110), and the tube body (420) is connected to the channel expansion sections (121).

7. The method for prefabricating lining components of a prestressed shield tunnel according to claim 6, characterized in that: The method further comprises: The channel fixing mold (440) comprises a fixing end mold (450) and an expansion section mold (460). The fixed end mold (450) is connected to the tube body (420), and the end of the expansion section mold (460) with a smaller diameter is connected to the fixed end mold (450), so as to restrict the concrete from forming the channel expansion section (121) while fixing the end of the tube body (420). The end of the expansion section mold (460) with a larger diameter is bolted to the connection end (481) in a manner of penetrating the end of the segment mold to fix the expansion section mold (460).

8. The method for prefabricating lining components of a prestressed shield tunnel according to claim 6 or 7, characterized in that: The method further comprises: The channel platform mold (480) is arranged between the expansion section mold (460) and the segment mold, so that the expansion section mold (460) is pressed against the channel platform mold (480). When the concrete is set, a demoulding platform (123) is formed around the external opening of the channel expansion section (121) by the channel platform mold (480), and the side of the demoulding platform (123) is inclined relative to the cross-section of the channel expansion section (121) to form a demoulding angle (482).

9. The method for prefabricating lining components of a prestressed shield tunnel according to any one of claims 6 to 7, characterized in that: The channel platform mold (480) is fixed on the segment mold by the connecting end (481). The channel platform mold (480) is a sheet with inclined contours on all sides, and the inclined surface of the channel platform mold (480) faces the expansion section mold (460). The angle between the inclined surface of the channel platform mold (480) and its central axis is the demoulding angle (482).

10. The method for prefabricating lining components of a prestressed shield tunnel according to claim 9, characterized in that: The demoulding angle (482) of the channel platform mold (480) has a value range of 10 to 75 degrees.

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