High-pressure water passing rectangular jacking pipe joint composite connection structure and construction method thereof

Abstract

The present application belongs to the technical field of rectangular jacking pipe engineering, and provides a high-pressure water passing rectangular jacking pipe joint composite connection structure and a construction method thereof. The two ends of the pipe joint are provided with sockets or spigots connected with other pipe joints according to F type socket joints, the inner wall of the pipe joint is provided with an annular boss, the annular boss is located at the axial center position of the pipe joint, the cross section is similar to the cross section of the pipe joint, and the two end faces of the annular boss are reserved with post-poured joints; the composite connection structure is composed of F type socket joints connecting two adjacent pipe joints and post-poured reinforced concrete connecting annular bosses of two adjacent pipe joints. The post-poured reinforced concrete can improve the ability of the pipe joint to resist uneven settlement and the waterproof ability from inside to outside. When the composite connection structure is constructed, a door-shaped movable formwork trolley is used to erect the formwork; the formwork trolley is a kind of assembled structure, which is extremely convenient to transport and disassemble, can reduce the engineering cost, can achieve high construction precision, can improve the construction safety, and can ensure the construction quality of the post-poured reinforced concrete.

Description

Technical Field

[0001] This invention relates to a composite connection structure for high-pressure water-passing rectangular jacking pipe sections and its construction method; it belongs to the technical field of rectangular jacking pipe engineering. Background Technology

[0002] With the expansion of urban scale and the large-scale development of urban population, large-section rectangular pipe jacking construction, as a trenchless pipeline construction technology, has developed rapidly in recent years and is widely used in power lines, underground transportation, water pipelines, and other fields due to issues such as urban traffic, environmental protection, and temporary land use in urban municipal engineering. Pipe jacking construction uses the thrust of the main jacking cylinder and the pipeline relay to push the tunneling machine from the working shaft through the soil layer to the receiving shaft, where it is lifted up. Simultaneously, prefabricated reinforced concrete working pipe sections are laid one by one following the tunneling machine, with joints used to connect the pipe sections.

[0003] Current rectangular pipe jacking joints typically employ the traditional F-type socket joint design. This type of F-type joint only uses one or two layers of rubber waterproofing at the pipe joint. Therefore, when uneven settlement occurs at the jacking site, causing excessive opening between pipe sections, leakage is highly likely, leading to numerous secondary problems. Patent CN113202991A uses two rigid collars and two annular grooves to enhance the leak-proof properties of the pipe jacking joint; patent CN207880195U uses a single annular connecting bolt joint to strengthen the joint's rigidity, addressing the issue of insufficient joint rigidity.

[0004] However, these technical methods primarily enhance the external waterproofing of the pipe jacking system, leaving only a single sealing strip inside. Furthermore, the rigidity of the pipe joints is generally insufficient. Over long-term operation, due to uneven ground settlement, the waterproofing effect gradually decreases. Therefore, these pipe joint types are only suitable for pipeline and transportation pipe jacking facilities. When the pipe jacking system is designed for water transport, the high water pressure inside necessitates extremely high requirements for its leak-proof and deformation-resistant capabilities from the inside out. Even after prolonged operation, the deformation of the pipe joints must be minimal, and leakage from the inside out must be prevented. Therefore, how to solve the problem of strictly resisting pipe joint deformation and achieving a high standard of waterproofing from the inside out has become a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a composite connection structure for high-pressure water-passing rectangular jacking pipe sections and its construction method. This structure uses a traditional F-type socket joint and post-cast reinforced concrete to form a composite connection structure for pipe sections. The method is simple in principle and easy to operate, and can effectively improve the longitudinal stiffness of the rectangular jacking pipe section joint, enhance the deformation resistance of the jacking pipe, and strictly prevent water leakage from the inside to the outside.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a composite connection structure for high-pressure water-passing rectangular jacking pipe sections, comprising two pipe sections connected by an F-type socket joint. Each of the two pipe sections has an annular boss on its inner wall, the annular boss being located at the center of the axial direction of the corresponding pipe section, and having a cross-section similar to that of the corresponding pipe section. Post-cast joints are reserved at both ends of the annular boss. Reinforced concrete is poured between the two opposing annular bosses of adjacent pipe sections to form a composite connection structure for the pipe sections. The reinforcing bars in the post-cast reinforced concrete are connected to the post-cast joints. The F-type socket joint is a flexible connection, while the post-cast reinforced concrete is a rigid connection. The combination of the two forms a composite connection structure for the pipe sections, which can ensure waterproofing of the outside of the pipe during the construction and operation and maintenance of the rectangular jacking pipe, and also ensure that high-pressure water passes through the pipe section without leakage during operation and maintenance.

[0008] As a preferred embodiment of the present invention, the thickness of the annular boss is 0.3-0.5 times the total wall thickness of the pipe section, and the length of the annular boss is 0.7-0.8 times the axial length of the pipe section.

[0009] As a preferred embodiment of the present invention, the reserved post-cast joint is a joint of multiple reserved reinforcing bars, one end of which is built into the annular boss and the other end is exposed; the reserved reinforcing bar joint uses the same reinforcing bars as the main reinforcing bars of the pipe section, and the exposed length is greater than or equal to 20d, where d is the diameter of the main reinforcing bar.

[0010] As a preferred embodiment of the present invention, the concrete in the post-cast reinforced concrete is shrinkage-compensating concrete, and its strength is the same as that of the pipe section concrete; the reinforcing bars in the post-cast reinforced concrete are the same as the main reinforcing bars of the pipe section, and the lap length of the joint with the reserved reinforcing bars is greater than or equal to 20d, where d is the diameter of the main reinforcing bar.

[0011] As a preferred embodiment of the present invention, a waterproof material is applied to the construction joint between the post-cast reinforced concrete and the inner wall of the pipe section. The waterproof material is preferably a polymer cement waterproof slurry, and the polymer cement waterproof slurry is preferably a cement-based penetrating crystalline waterproof coating.

[0012] Secondly, the present invention provides a construction method for a composite connection structure of a high-pressure water-passing rectangular jacking pipe section, comprising the following steps:

[0013] S1. Prefabricate pipe sections in the factory according to design requirements. Set an annular boss with post-pouring joints on both ends at the center of the inner wall of the pipe section. Set F-type sockets at both ends of the pipe section. Push the pipe section into place on the construction site according to construction requirements.

[0014] S2. Reinforcing bars are used to connect the corresponding post-cast joints on the annular protrusions of two adjacent pipe sections, and a reinforcing mesh is erected in the circumferential direction of the pipe section.

[0015] S3. Pour the post-cast reinforced concrete base plate inside the pipe section;

[0016] S4. Erect formwork inside the pipe section at the positions corresponding to the post-cast reinforced concrete side plates and top plates, and pour the post-cast reinforced concrete side plates and top plates on site to form a complete post-cast reinforced concrete.

[0017] S5. After the post-cast reinforced concrete reaches the design strength, remove the formwork and waterproof the inner circumference of the pipe section.

[0018] As a preferred embodiment of the present invention, in S1, during the prefabrication of the pipe section, a number of pre-embedded bolts are provided on the annular protrusions of the top plate and the two side plates of the pipe section near the two ends of the annular protrusions. The distance between the pre-embedded bolts and the two ends of the annular protrusions is 10-30cm, preferably 20cm; the diameter of the pre-embedded bolts is 2cm-5cm, preferably 4cm; one end of the pre-embedded bolt is exposed on the inner circumference of the pipe section, and the exposed length is 2-10cm, preferably 5cm.

[0019] As a preferred embodiment of the present invention, in S1, during the prefabrication of the pipe section, a vent pipe is installed at the bottom of the top plate of the pipe section using a snap-fit ​​suspension. The air inlet of the vent pipe is located in the annular cavity between the annular protrusions of two adjacent pipe sections, and the air outlet of the vent pipe is exposed on the inner circumference of the pipe section. Preferably, the snap-fit ​​section of the vent pipe is made of rigid PVC pipe, and the drooping section of the vent pipe is connected to the rigid PVC pipe using a soft rubber pipe of the same diameter as the rigid PVC pipe. More preferably, the suspension height of the vent pipe is half the height of the post-cast reinforced concrete, and the suspension position is the middle of the post-cast reinforced concrete top plate. The exposed length of the vent pipe is 10-30cm, preferably 20cm, and the diameter of the vent pipe is preferably 2cm.

[0020] As a preferred embodiment of the present invention, in S4, a portal-shaped mobile template trolley is used to erect templates inside the pipe section for the pouring of post-cast reinforced concrete side plates and top plates.

[0021] The portal-shaped mobile template trolley includes several wheels, two side formwork bases, two side forms, a top form, two movable corner forms, a longitudinal stabilizing truss, and a transverse stabilizing truss. The wheels are respectively installed at the bottom of the two side formwork bases. The lower ends of the two side forms are respectively installed on the two side formwork bases. The upper ends of the two side forms are movably and fixedly connected to the left and right ends of the top form through the two movable corner forms. Each side form has a set of transverse stabilizing trusses on its inner side, and the two sets of transverse stabilizing trusses are connected by several first telescopic rods. A longitudinal stabilizing truss is also provided on the side formwork base to fix the side forms. The outer wall of the movable corner form has a chamfer that matches the chamfer of the inner wall of the pipe section top plate. The wheels are omnidirectional wheels capable of moving in any direction. The first telescopic rods are preferably hydraulic telescopic rods. The longitudinal and transverse stabilizing trusses ensure the structural stability of the portal-shaped mobile template trolley, while the movable corner forms and hydraulic telescopic rods enable the transverse movement of the side forms and the vertical movement of the top form.

[0022] In a preferred embodiment of the present invention, the movable corner mold and the top mold in the portal-shaped movable template trolley are movably fixedly connected in the following manner:

[0023] The movable corner mold has a sliding plate in the lateral direction. The upper surface of the sliding plate slides in contact with the lower surface of the top mold. The sliding plate has several temporary fastening bolts, and the top mold has several fastening screw holes that match the temporary fastening bolts. A second telescopic rod is also provided between the movable corner mold and the top mold. When the second telescopic rod extends or retracts, the minimum contact length between the sliding plate and the top mold is 0.3-0.5 times the maximum contact length between the sliding plate and the top mold. By adjusting the fastening position of the temporary fastening bolts and the length of the second telescopic rod, the relative position of the movable corner mold and the top mold can be changed, thereby achieving a movable fixed connection between the movable corner mold and the top mold. Further preferably, the upper surface of the sliding plate is provided with lubricating material or a sliding plate support. The sliding plate support is preferably a PTFE sliding plate support, and the lubricating material is preferably grease or petroleum jelly. The second telescopic rod is preferably a hydraulic telescopic rod. After the second telescopic rod extends, the gap between the movable corner mold and the top mold is filled with a pad, which is a steel box pad.

[0024] The connection method between the two side molds and the movable corner mold is the same as the connection method between the top mold and the movable corner mold.

[0025] As a preferred embodiment of the present invention, in the portal-shaped mobile formwork trolley, each of the two side molds and the top mold is provided with a number of screw holes that match the pre-embedded bolts of the pipe section. After the screw holes on the side molds and the top mold pass through the pre-embedded bolts on the pipe section, nuts are used to fasten the side molds and the top mold to the top plate and side wall of the pipe section. Each of the two side plates is provided with a concrete pumping port. The top mold of the portal-shaped mobile formwork trolley is provided with a venting pipe reserved hole with a diameter matching the venting pipe for the venting pipe to pass through.

[0026] In a preferred embodiment of the present invention, in the portal-shaped movable formwork trolley, at least one water-stop rubber strip is attached to the periphery of the two side forms and the top formwork, covering the area of ​​the post-cast reinforced concrete side slabs and the top slab; preferably, the thickness of the water-stop rubber strip is 4mm, and the width of the water-stop rubber strip is 0.5 (L). * -L), where L * L represents the longitudinal length of the portal-shaped movable formwork trolley, and L represents the longitudinal length of the post-cast reinforced concrete.

[0027] As a preferred embodiment of the present invention, in S4, the two side plates and the top plate of the post-cast reinforced concrete are poured on site according to the following method:

[0028] Pumped concrete was used to pour the two side plates and the top plate of the post-cast reinforced concrete from bottom to top. When the cement slurry flowed down the vent pipe, the vent pipe was closed, and then the concrete was poured according to the concrete pouring volume calculated by formula (1) until the top plate was full.

[0029] V=0.2ζLB (1)

[0030] In the formula: V is the amount of concrete poured after sealing the vent pipe; L is the longitudinal length of the post-poured reinforced concrete; B is the width of the pipe section; ζ is the reduction factor, which is related to the concrete slump. When the slump is greater than or equal to 150 mm, ζ = 0.8; when the slump is greater than 100 mm but less than 150 mm, ζ = 0.5; and when the slump is less than or equal to 100 mm, ζ = 0.3.

[0031] As a preferred embodiment of the present invention, waterproof material is applied to the construction joint between the post-cast reinforced concrete and the inner wall of both ends of the pipe section to waterproof the inner circumference of the pipe section.

[0032] As a preferred embodiment of the present invention, a traction device is provided in front of the portal-shaped mobile template trolley and connected to the portal-shaped mobile template trolley. The traction device is preferably a winch. The longitudinal movement of the portal-shaped mobile template trolley inside the pipe section is controlled by the traction device.

[0033] Compared with the prior art, the present invention has the following beneficial technical effects:

[0034] 1) The rectangular jacking pipe joint using this technology has a large longitudinal stiffness because part of the inner wall of the jacking pipe is an integral concrete structure poured after the jacking pipe is jacked into place. Even if there is a large uneven settlement of the stratum, the jacking pipe will not undergo large shear deformation, thus preventing water leakage in principle. On the other hand, high-pressure water jacking pipes have extremely high requirements for water leakage prevention under long-term operation, especially the requirement to achieve water leakage from the inside to the outside of the jacking pipe. This solution can well meet this requirement. However, due to the structural characteristics of the F-type socket structure of the pipe section, the existing technology is a flexible connection structure that cannot cope with the large shear deformation that may occur under long-term operation, thus reducing its structural waterproof function. Secondly, because its waterproofing measures are from the outside to the inside, its internal waterproofing measures are extremely simple. Water leakage from the inside to the outside may occur in high-pressure water jacking pipes, and this problem will become more and more obvious with the longer the operation time. Water leakage from the inside to the outside may also affect the natural environment and residents' lives.

[0035] 2) On-site construction often relies on temporary scaffolding to support the internal construction of pipe sections. However, scaffolding and manual operation pose safety risks to construction workers and make it difficult to guarantee construction accuracy. To achieve the construction of composite connection structures, this technical solution adopts a new type of mobile formwork trolley for this type of composite joint. This formwork trolley is a mobile and reusable structure, which can ensure faster construction and reduced construction costs. Moreover, since the mobile formwork trolley is also a prefabricated structure, its transportation and disassembly are extremely convenient, further reducing project costs. On the other hand, unlike traditional wooden formwork that requires a large number of workers for manual assembly, the mobile formwork trolley is assembled using a hydraulic device and fixed with bolts, greatly reducing the uncontrollable factors of manual labor, thus achieving higher construction accuracy and improving construction safety. In addition, multiple pre-embedded bolts are installed on the pipe section, which are exposed on the inner circumference of the pipe section. The installation of pre-embedded bolts can greatly improve the construction accuracy of the side formwork and top formwork. At least one water-stop rubber strip is also installed on the side formwork and top formwork to ensure the construction accuracy and quality of the post-cast reinforced concrete top slab and side slab, avoid defects such as honeycomb and pitting, and ensure the waterproof effect of the post-cast reinforced concrete from a structural point of view. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the annular boss on the pipe section.

[0037] Figure 2 This is a schematic diagram of a composite connection structure for pipe sections.

[0038] Figure 3 A schematic diagram showing the pre-embedded bolts and vent pipes for the pipe section.

[0039] Figure 4 This is a front view of a portal-shaped mobile template trolley.

[0040] Figure 5 This is a schematic diagram of the side mold and the base of the U-shaped movable template trolley.

[0041] Figure 6 This is a schematic diagram of the movable corner mold of the U-shaped movable template trolley.

[0042] Figure 7 This is a structural diagram of a type F socket.

[0043] Figure 8 This is a construction diagram of a portal-shaped mobile formwork trolley.

[0044] Figure 9 This is a schematic diagram of the movement of the portal-shaped mobile template trolley.

[0045] In the diagram: 101, front pipe section; 102, rear pipe section; 103, annular boss; 104, socket; 105, spigot; 106, reserved rebar joint; 107, embedded bolt; 108, annular cavity; 111, steel collar; 112, water-swellable rubber strip; 113, polyurethane sealing strip; 114, rubber sealing ring; 115, inner steel lining plate; 116, force transmission gasket.

[0046] 201, Post-cast reinforced concrete; 202, Reinforcing steel; 203, Shrinkage-compensating concrete; 204, Vent pipe; 205, Waterproofing material;

[0047] 301, Portal-shaped mobile formwork trolley; 302, Wheel; 303, Side formwork base; 304, Side formwork; 305, Top formwork; 306, Movable corner formwork; 307, Lateral stabilizing truss; 308, Longitudinal stabilizing truss; 309, First telescopic rod; 310, Second telescopic rod; 311, Slide plate; 312, Temporary fastening bolt; 313, Fastening bolt hole; 314, Steel box pad; 315, PTFE slide plate support; 316, Bolt hole; 317, Nut; 318, Vent pipe reserved hole; 319, Concrete pump inlet. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0049] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "left end," and "right end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0050] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed", "equipped with", "connected", etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a direct connection. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] See Figure 1-6 ;

[0052] This invention provides a composite connection structure for high-pressure water-passing rectangular jacking pipe sections, comprising two pipe sections connected by an F-type socket joint. Each of the two pipe sections has an annular boss 103 on its inner wall. The annular boss 103 is located at the center of the axial direction of the corresponding pipe section, and its cross-section is similar to that of the corresponding pipe section. Post-cast joints are reserved on both ends of the annular boss 103. Reinforced concrete 201 is poured between the two opposing annular bosses 103 of the two adjacent pipe sections to form a composite connection structure for the pipe sections. The reinforcing bars in the post-cast reinforced concrete 201 are connected to the post-cast joints.

[0053] Figure 1 The diagram shows a pipe section. The front end of the pipe section is provided with a spigot 105 and the rear end of the pipe section is provided with a socket 104. The pipe section includes a rear pipe section 102 and a front pipe section 101. The spigot 105 of the rear pipe section 102 is inserted into the socket 104 of the front pipe section 101 to form an F-type spigot and socket.

[0054] Figure 2 This is a schematic diagram of a composite connection structure for pipe sections. The composite connection structure consists of an F-type socket connecting two adjacent pipe sections (rear pipe section 102 and front pipe section 101) and a post-cast reinforced concrete 201 connecting annular bosses 103 of the two adjacent pipe sections (rear pipe section 102 and front pipe section 101). The reinforcing bars 202 in the post-cast reinforced concrete 201 are connected to the post-cast joint. An annular cavity 108 is formed between the annular bosses 103 of the rear pipe section 102 and the annular bosses 103 of the front pipe section 101. After the pipe jacking is completed, reinforcing bars 202 and a reinforcing mesh are laid in the annular cavity 108, and then concrete is poured to form the post-cast reinforced concrete 201.

[0055] The F-type socket joint is a flexible connection, while the post-cast reinforced concrete 201 is a rigid connection. The combination of the two forms a composite connection structure for the pipe section, which can ensure waterproofing of the outside of the pipe during the construction and operation and maintenance of the rectangular jacking pipe, and also ensure that high-pressure water passes through the pipe section during operation and maintenance without leakage.

[0056] The thickness of the annular boss is 0.3-0.5 times the wall thickness of the pipe section, and the length of the annular boss is 0.7-0.8 times the axial length of the pipe section; furthermore, the thickness of the annular boss is determined according to formula (2):

[0057]

[0058] Where: S is the circumference of the pipe section, h1 is the thickness of the annular boss, F is the jacking force during pipe jacking construction, [σ] is the axial compressive strength of the pipe section, and h is the wall thickness of the pipe section;

[0059] The geometric dimensions and wall thickness of the pipe sections are determined according to the relevant design specifications for rectangular pipe jacking, such as the "Technical Specification for Rectangular Pipe Jacking Engineering CECS716-2020".

[0060] The post-cast joint consists of multiple pre-reserved steel bar joints 106. One end of each pre-reserved steel bar joint 106 is embedded within the annular boss 103 of the pipe section, while the other end is exposed in the annular cavity 108. The pre-reserved steel bar joint 106 uses the same steel bars as the main reinforcement of the pipe section, with an exposed length greater than or equal to 20d, where d is the diameter of the main reinforcement. The specific exposed length can be calculated according to the "Code for Design of Concrete Structures GB50010". The concrete in the post-cast reinforced concrete 201 is shrinkage-compensating concrete 203, with the same strength as the concrete in the pipe section. The steel bars 202 in the post-cast reinforced concrete 201 use the same steel bars as the main reinforcement of the pipe section, and the lap length with the pre-reserved steel bar joint is greater than or equal to 20d. The specific lap length can be calculated according to the "Code for Design of Concrete Structures GB50010".

[0061] Secondly, the present invention provides a construction method for a composite connection structure of a high-pressure water-passing rectangular jacking pipe section, comprising the following steps:

[0062] S1. Prefabricate pipe sections in the factory according to design requirements. Set an annular boss 103 with post-cast joints reserved on both ends at the center of the inner wall of the pipe section. Set F-type sockets (including socket 104 and spigot 105) at both ends of the pipe section. Push the pipe section into place on the construction site according to construction requirements.

[0063] S2. In the annular cavity 108, steel bars 202 are used to connect with the corresponding reserved steel bar joints 106 on the annular bosses 103 of the two adjacent pipe sections (rear pipe section 102 and front pipe section 101), and steel mesh is erected in the circumferential direction of the pipe section.

[0064] S3. Pour the base plate of the post-cast reinforced concrete 201 inside the pipe section;

[0065] S4. Erect formwork inside the pipe section at the positions corresponding to the side plate and top plate of the post-cast reinforced concrete 201, and pour the side plate and top plate of the post-cast reinforced concrete 201 on site to form a complete post-cast reinforced concrete 201.

[0066] S5. After the post-cast reinforced concrete 201 reaches its design strength, remove the formwork and perform waterproofing treatment on the inner circumference of the pipe section. The preferred embodiment of the construction method for the high-pressure water-passing rectangular jacking pipe section composite connection structure of the present invention is described below:

[0067] In S1, during the prefabrication of the pipe section, several pre-embedded bolts 107 are provided on the annular bosses 103 of the top plate and the two side plates of the pipe section near the two end faces of the annular bosses 103. The distance between the pre-embedded bolts 107 and the two end faces of the annular bosses 103 is 10-30cm, preferably 20cm. The diameter of the pre-embedded bolts 107 is 2cm-5cm, preferably 4cm. One end of the pre-embedded bolt is exposed on the inner circumference of the pipe section, and the exposed length is 2-10cm, preferably 5cm.

[0068] In S1, during the prefabrication of pipe sections, a vent pipe 204 is suspended and installed at the bottom of the top plate of the pipe section using a snap-fit ​​method. The air inlet of the vent pipe 204 is located in the annular cavity 108 between the annular protrusions 103 of two adjacent pipe sections (rear pipe section 102 and front pipe section 101), and the air outlet of the vent pipe 204 is exposed on the inner circumference of the pipe section. Preferably, the snap-fit ​​section of the vent pipe 204 is made of rigid PVC pipe, and the drooping section of the vent pipe 204 is connected to the rigid PVC pipe using a soft rubber pipe of the same diameter as the rigid PVC pipe. More preferably, the suspension height of the vent pipe 204 is half the height of the annular cavity 108, the suspension position is the middle position of the top of the annular cavity 108, the exposed length of the vent pipe 204 is 10-30cm, preferably 20cm, and the diameter of the vent pipe 204 is preferably 2cm. Figure 3 A schematic diagram of the pre-embedded bolts 107 and vent pipe 204 for the pipe section.

[0069] In S4, a portal-shaped mobile formwork trolley 301 is used to erect formwork inside the pipe section for the pouring of the post-cast reinforced concrete 201 side plate and top plate.

[0070] Figure 4 This is a front view of the U-shaped movable template trolley 301. Figure 5This is a side view of a portal-shaped mobile formwork trolley 301. The portal-shaped mobile formwork trolley 301 includes several wheels 302, two side formwork bases 303, two side forms 304, a top formwork 305, two movable corner forms 306, a longitudinal stabilizing truss 308, and a transverse stabilizing truss 307. The wheels 302 are respectively installed on the bottom of the two side formwork bases 303. The lower ends of the two side forms 304 are respectively installed on the two side formwork bases 303. The upper ends of the two side forms 304 are movably and fixedly connected to the left and right ends of the top formwork 305 through the two movable corner forms 306. Each of the two side forms 304 has a set of transverse stabilizing trusses on its inner side. The frame 307 is connected by several first telescopic rods 309 between two sets of transverse stabilizing trusses 307; the side formwork base 303 is also provided with a longitudinal stabilizing truss 308 to fix the side formwork 304; the outer wall of the movable corner formwork 306 is provided with a chamfer that matches the chamfer of the inner wall of the top plate of the pipe section; the wheels 302 are universal wheels that can move in any direction; the first telescopic rods 309 are preferably hydraulic telescopic rods; the structural stability of the portal-shaped movable template trolley 301 is ensured by the longitudinal stabilizing truss 308 and the transverse stabilizing truss 307, and the transverse movement of the side formwork 304 and the vertical movement of the top formwork 305 are realized by the movable corner formwork 306 and the hydraulic telescopic rods.

[0071] Figure 6 This is a schematic diagram of the movable corner mold of the portal-shaped moving template trolley. The movable corner mold 306 and the top mold 305 are connected in a movable and fixed manner as follows:

[0072] In the U-shaped movable template trolley 301, the movable corner mold 306 has a sliding plate 311 in the horizontal direction. The upper surface of the sliding plate 311 slides in contact with the lower surface of the top mold 305. The sliding plate 311 is provided with several temporary fastening bolts 312, and the top mold 305 is provided with several fastening screw holes 313 that match the temporary fastening bolts 312. A second telescopic rod 310 is also provided between the movable corner mold 306 and the top mold 305. When the second telescopic rod 310 extends or retracts, the minimum contact length between the sliding plate 311 and the top mold 305 is 0.3-0.5 times the maximum contact length between the sliding plate 311 and the top mold 305. This can be adjusted... The tightness of the temporary fastening bolts and the length of the second telescopic rod 310 control the relative positions of the movable corner mold 306 and the top mold 305, achieving a movable fixed connection between the movable corner mold 306 and the top mold 305; more preferably, the upper surface of the slide plate 311 is provided with a lubricating material or a slide plate 311 type support, the slide plate type support is preferably a PTFE slide plate type support 315, and the lubricating material is preferably grease or petroleum jelly; the connection method between the two side molds 304 and the movable corner mold 306 is the same as the connection method between the top mold 305 and the movable corner mold 306; the second telescopic rod 310 is preferably a hydraulic telescopic rod.

[0073] Referring to the movable fixed connection between the movable corner mold 306 and the top mold 305, the movable fixed connection between the two side molds 304 and the movable corner mold 306 is achieved in the following manner:

[0074] The movable corner mold 306 is also provided with a sliding plate 311 in the vertical direction. The outer surface of the sliding plate 311 slides in contact with the inner surface of the top mold 305. The sliding plate 311 is provided with several temporary fastening bolts 312. The top mold 305 is provided with several fastening screw holes 313 that match the temporary fastening bolts 312. A second telescopic rod 310 is also provided between the movable corner mold 306 and the side mold 304. When the second telescopic rod 310 extends or retracts, the minimum contact length between the sliding plate 311 and the top mold 305 is 0.3-0.5 times the maximum contact length between the sliding plate 311 and the top mold 305. By adjusting the tightness of the temporary fastening bolts 312 and the length of the second telescopic rod 310, the relative position of the movable corner mold 306 and the side mold 304 is controlled, so as to realize the movable fixed connection between the movable corner mold 306 and the side mold 304.

[0075] In the portal-shaped mobile formwork trolley 301, each of the two side molds 304 and the top mold 305 is provided with several screw holes 316 that match the pre-embedded bolts 107 on the pipe section. After the screw holes 316 on the side molds 304 and the top mold 305 pass through the pre-embedded bolts 107 on the pipe section, nuts 317 are used to fasten the side molds 304 and the top mold 305 to the top plate and side plate of the pipe section. Each of the two side plates is provided with a concrete pumping port 319. The top mold 305 of the portal-shaped mobile formwork trolley 301 is provided with a venting pipe reserved hole 318 with a diameter matching the venting pipe 204 for the venting pipe 204 to pass through. The pre-embedded bolts 107 are provided on the inner wall of the pipe section and exposed on the inner circumference of the pipe section, which facilitates the positioning of the side molds 304 and the top mold 305, and at the same time can improve the tightness of the side molds 304 and the top mold 305 to the inner wall of the pipe section, ensuring the construction quality and construction accuracy of the post-poured reinforced concrete 201.

[0076] In a preferred embodiment, in the portal-shaped movable formwork trolley 301, at least one water-stop rubber strip is pasted around the periphery of the two side molds 304 and the top mold 305, covering the annular cavity 108 of the top plate and side plate of the pipe section (or the location of the post-cast reinforced concrete 201 to be constructed) within the range of the water-stop rubber strip; preferably, the thickness of the water-stop rubber strip is 4mm, and the width of the water-stop rubber strip is 0.5 (L). * -L), where L * L is the longitudinal length of the portal-shaped movable formwork trolley 301, and L is the longitudinal length of the post-cast reinforced concrete 201.

[0077] In S4, the side slabs and top slab of the post-cast reinforced concrete 201 shall be poured on site according to the following method:

[0078] Pumped concrete is used to pour the side plate and top plate of the post-cast reinforced concrete 201 from bottom to top. When the cement slurry flows down the vent pipe 204, the vent pipe 204 is closed, and the concrete pouring volume calculated according to formula (1) is continued to pour concrete until the top plate is full.

[0079] V=0.2ζLB (1)

[0080] In the formula: V is the amount of concrete poured after sealing and ventilation; L is the longitudinal length of the post-cast reinforced concrete 201; B is the width of the pipe section; ζ is the reduction factor, which is related to the concrete slump. When the slump is greater than or equal to 150 mm, ζ = 0.8; when the slump is greater than 100 mm but less than 150 mm, ζ = 0.5; when the slump is less than or equal to 100 mm, ζ = 0.3.

[0081] In S5, waterproof material 205 is applied to the construction joint between the post-cast reinforced concrete 201 and the annular boss 103 of the rear pipe section 102 and the annular boss 103 of the front pipe section 101 to waterproof the inner circumference of the pipe section. The waterproof material 205 is preferably a polymer cement slurry, and the polymer cement slurry is preferably a cement-based penetrating crystalline waterproof coating.

[0082] In a preferred embodiment, a traction device is provided in front of the portal-shaped mobile formwork trolley 301 and connected to the portal-shaped mobile formwork trolley 301. The traction device is preferably a winch. The longitudinal movement of the portal-shaped mobile formwork trolley 301 inside the pipe section is controlled by the traction device, making construction efficient and convenient.

[0083] The technical solution described in this invention has the following technical effects:

[0084] By setting a reserved post-cast section (i.e., the location of the annular cavity 108) in the pipe section, after the rectangular jacking pipe is jacked into place, reinforced concrete is poured to form the post-cast reinforced concrete 201, which connects the annular boss 103 of the front pipe section 101 and the annular boss 103 of the rear pipe section 102 into a whole. This local rigid connection method (i.e., composite connection) can improve the longitudinal stiffness of the pipe section and its ability to resist uneven settlement to a certain extent compared with the existing flexible connection method, and prevent large shear deformation between pipe sections, thereby preventing water leakage in principle. The post-cast reinforced concrete 201 itself is also a good waterproof barrier, which has a good effect on achieving water leakage prevention from the inside to the outside of the jacking pipe.

[0085] Example 1;

[0086] See Figure 1-9 ;

[0087] This embodiment provides a composite connection structure for high-pressure water-passing rectangular jacking pipe sections and its construction method. This embodiment only further elaborates on the F-type socket and the portal-shaped movable formwork trolley 301. For other contents, please refer to the above specific implementation method and existing technologies such as rectangular jacking pipe design and construction, concrete design and construction, etc., which will not be repeated here.

[0088] There are many existing descriptions of F-type socket joints, such as the "Technical Specification for Rectangular Pipe Jacking Engineering CECS716-2020". Here, only one of them is selected as a preferred embodiment for illustration. The F-type socket joint includes a socket 104 provided on the front pipe section 101 and a spigot 105 provided on the rear pipe section 102. Figure 7 This is a structural diagram of a type F socket.

[0089] The socket 104 includes a steel collar 111, a water-swellable rubber strip 112, a polyurethane sealing strip 113, and an inner steel plate 115. The steel collar 111 is located on the outer wall of the rear pipe section 102 and is flush with the outer surface of the rear pipe section 102. The steel collar 111 is fixed by a steel bar embedded in the rear pipe section 102. The water-swellable rubber strip 112 is located between the outer wall of the rear pipe section 102 and the fixed end of the steel collar 111. The polyurethane sealing strip 113 is located at the connection between the middle of the steel collar 111 and the end of the outer wall of the rear pipe section 102. The inner steel plate 115 is located at the end of the inner wall of the rear pipe section 102.

[0090] The spigot 105 includes two rubber sealing rings 114 and an inner steel lining plate 115. The two rubber sealing rings 114 are arranged along the longitudinal direction of the pipe section on the outer periphery of the outer wall of the rear pipe section 102, and the inner steel lining plate 115 is arranged at the end of the inner wall of the front pipe section 101. During pipe jacking construction, a force transmission pad 116 is placed between the socket 104 and the spigot 105 to avoid uneven stress on the pipe section. After the pipe jacking construction is completed, a polyurethane sealing strip 113 is provided on the inner side of the gap between the socket 104 and the spigot 105.

[0091] The two transverse stabilizing trusses 307 on the portal-shaped movable template trolley 301 are arranged longitudinally. Each transverse stabilizing truss 307 is provided with at least one first telescopic rod 309, which is arranged transversely. There are at least eight second telescopic rods 310, of which at least one vertically arranged second telescopic rod 310 is provided at each of the four corners where the movable corner mold 306 is connected to the side mold 304, and at least one transversely arranged second telescopic rod 310 is provided at each of the four corners where the movable corner mold 306 is connected to the top mold 305.

[0092] The diameter of the pre-embedded bolt 107 in the pipe section is Each pipe section has four annular bosses 103 on the side plate near the front and rear faces of the annular bosses 103, and two annular bosses 103 on the top plate near the front and rear faces of the annular bosses 103. The longitudinal distance between the pre-embedded bolts 107 and the annular cavity 108 (or the front and rear faces of the annular bosses 103) is 20cm. The diameter of the pre-embedded bolts 107 is 4cm, and their exposed length is 5cm.

[0093] The snap-fit ​​section of the vent tube 204 adopts The rigid PVC pipe has a lower section made of a soft rubber pipe of the same diameter. The outer sleeve is connected to the PVC pipe and hangs down through the vent pipe reserved hole 318 of the top mold 305 of the portal-shaped moving template trolley 301 in step 4. The suspension height of the vent pipe 204 is half the height of the annular cavity 108, and the suspension position is in the middle of the annular cavity 108 on the top plate of the pipe section. The exposed height of the vent pipe 204 is 20cm.

[0094] The initial pouring height of the post-cast reinforced concrete 201 side plate is 35cm, which is 30cm greater than the radius of the bottom chamfer of the pipe section.

[0095] In this embodiment, the side mold 304 and top mold 305 of the portal-shaped movable template trolley 301 are both made of 8mm thick steel plates. The inner side of the steel plates is reinforced with 30cm×30cm longitudinal and transverse ribs, with a rib thickness of 5mm and a height of 10cm.

[0096] The side formwork 304 and top formwork 305 of the portal-shaped movable formwork trolley 301 are each equipped with four φ20 screw holes 316, the positions of which match the pre-embedded bolts 107 of the pipe sections. A concrete pumping port 319 is left at the center of each of the two side plates, and a [missing information - likely a number] is left at the center of the top formwork 305. Ventilation tube pre-drilled hole 318, used to pass through ventilation tube 204.

[0097] A 4mm thick water-stop rubber strip is affixed around the perimeter of the side formwork 304 and top formwork 305 of the portal-shaped movable formwork trolley 301. The width of the rubber strip is 0.5 (L*-L), where L* is the longitudinal length of the portal-shaped movable formwork trolley 301 and L is the longitudinal length of the post-cast reinforced concrete 201. The corner points of the movable corner formwork 306 are rounded chamfers that fit the chamfer of the jacking pipe. The driving stroke of the hydraulic telescopic rod is set according to the site conditions, ranging from 30 to 70 cm, and is preferably 45 cm in this embodiment.

[0098] Figure 8 This is a construction schematic diagram of the portal-shaped mobile formwork trolley 301. Figure 9 The diagram illustrates the movement of the U-shaped movable formwork trolley 301, which erects formwork for the pouring of the post-cast reinforced concrete 201 top and side slabs using the following method:

[0099] After the T1.Gate-shaped movable formwork trolley 301 moves forward to the position of the bottom plate of the post-cast reinforced concrete 201, apply grease release agent to the outside of the formwork.

[0100] T2. Loosen the temporary fastening bolts 312 between the movable corner mold 306 and the side mold 304 from the fastening bolt holes 313, activate the vertically arranged second telescopic rod 310, and lift the top mold 305 and the movable corner mold 306 to be close to the top plate of the pipe section. Finely adjust the position of the U-shaped movable template trolley 301 so that the bolt hole 316 of the top mold 305 is aligned with the pre-embedded bolt 107 of the top plate. After passing the ventilation hose through the ventilation pipe reserved hole 318 of the top mold 305, use the temporary fastening bolts 312 to screw into the sliding plate 311 of the movable corner mold 306 and the fastening bolt holes 313 on the side mold 304 to fasten the sliding plate 311 to the top mold 305. Insert the steel box pad block 314 into the gap between the side mold 304 and the movable corner mold 306.

[0101] T3. Loosen the temporary fastening bolts 312 of the movable corner mold 306 and the top mold 305 from the fastening bolt holes 313. At the same time, activate the second telescopic rod 310 and the first telescopic rod 309 arranged laterally to open the side mold 304 and the movable corner mold 306 to fit tightly against the side plate of the pipe section. Finely adjust the position of the U-shaped moving template trolley 301 so that the bolt hole 316 of the side mold 304 is aligned with the pre-embedded bolt 107 of the side plate. Tighten the temporary fastening bolts 312 into the sliding plate 311 of the movable corner mold 306 and the fastening bolt holes 313 on the top mold 305 to fasten the sliding plate 311 to the top mold 305. Insert the steel box pad 314 into the gap between the top mold 305 and the movable corner mold 306.

[0102] T4. Insert the concrete pumping pipe into the concrete pumping port 319 of the left and right side formwork 304, and pour concrete from bottom to top from the side plate to the top plate.

[0103] T5. When the cement slurry flows down the vent pipe 204, cut off the soft vent pipe 204 and seal it. Then continue to pour concrete according to the concrete pouring volume calculated by formula (1) until the top slab is full.

[0104] T6. When the concrete reaches the demolding strength, first loosen the temporary fastening bolts 312 of the top mold 305 and the movable corner mold 306, remove the steel box pad of the top mold 305, activate the second telescopic rod 310 and the first telescopic rod 309 arranged laterally, retract the side mold 304 and the movable corner mold 306 so that the contact length between the sliding plate 311 and the top mold 305 is minimized, and then fasten the movable corner mold 306 and the top mold 305 with the temporary fastening bolts 312.

[0105] T7. Loosen the temporary fastening bolts 312 of the side mold 304 and the movable corner mold 306, remove the steel box pad 314 of the side mold 304, activate the vertically arranged second telescopic rod 310, retract the top mold 305 and the movable corner mold 306 to minimize the contact length between the slide plate 311 and the side mold 304, and then fasten the movable corner mold 306 and the side mold 304 with the temporary fastening bolts 312.

[0106] T8. Using a traction device, move the portal-shaped mobile formwork trolley 301 to the position of the next section of post-cast reinforced concrete 201. Proceed with steps T1-T7 for the construction of the next section of post-cast reinforced concrete 201, repeating this process until all post-cast reinforced concrete 201 inside the rectangular jacking pipe is completed. When constructing post-cast reinforced concrete 201 at other locations, the exposed embedded bolts 107 at the locations of the already constructed post-cast reinforced concrete 201 can be cut off. Apply a waterproofing material (such as cement-based penetrating crystalline waterproof coating) to the construction joint between the post-cast reinforced concrete 201 and the annular boss 103 of the pipe section for waterproofing. Existing products conforming to national standards can be used for cement-based penetrating crystalline waterproof coatings; details will not be elaborated here.

[0107] It should be understood that the accompanying drawings are only schematic diagrams, and the geometric dimensions of the structure shown in the drawings do not represent the actual structural dimensions and pipe section dimensions of the portal-shaped mobile formwork trolley 301 produced. Those skilled in the art can make some simple adjustments to the portal-shaped mobile formwork trolley 301 to adapt to engineering design and construction requirements.

[0108] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A construction method for a composite connection structure of a high-pressure water-passing rectangular jacking pipe section, characterized in that: The steps include the following: S1. Prefabricate pipe sections in the factory according to design requirements. Set an annular boss with post-pouring joints on both ends at the center of the inner wall of the pipe section. Set F-type sockets at both ends of the pipe section. Push the pipe section into place on the construction site according to construction requirements. S2. Reinforcing bars are used to connect the corresponding post-cast joints on the annular protrusions of two adjacent pipe sections, and a reinforcing mesh is erected in the circumferential direction of the pipe section. S3. Pour a reinforced concrete base slab inside the pipe section; S4. Erect formwork inside the pipe section at the positions corresponding to the post-cast reinforced concrete side plates and top plates, and pour the post-cast reinforced concrete side plates and top plates on site to form a complete post-cast reinforced concrete. S5. After the post-cast reinforced concrete reaches the design strength, remove the formwork and waterproof the inner circumference of the pipe section. The high-pressure water-passing rectangular jacking pipe section composite connection structure includes two pipe sections connected by an F-type socket. Each of the two pipe sections has an annular boss on its inner wall. The annular boss is located at the center of the corresponding pipe section's axial direction and has a cross-section similar to that of the corresponding pipe section. Post-cast joints are reserved on both ends of the annular boss. Reinforced concrete is poured between the two annular bosses of two adjacent pipe sections to form a composite connection structure. The reinforcing bars in the post-cast reinforced concrete are connected to the post-cast joints. The thickness of the annular boss is 0.3-0.5 times the total wall thickness of the pipe section, and the length of the annular boss is 0.7-0.8 times the axial length of the pipe section. The post-cast joint is a joint of multiple reserved reinforcing bars. The reserved reinforcing bars are made of the same reinforcing bars as the main reinforcing bars of the pipe section, and the exposed length is greater than or equal to 20d, where d is the diameter of the main reinforcing bar. The concrete in the post-cast reinforced concrete is shrinkage-compensating concrete, and the strength is the same as that of the pipe section concrete. The reinforcing bars in the post-cast reinforced concrete are made of the same reinforcing bars as the main reinforcing bars of the pipe section, and the lap length with the reserved reinforcing bar joint is greater than or equal to 20d. In S4, a portal-shaped mobile formwork trolley is used to erect the formwork; The portal-shaped mobile template trolley includes several wheels, two side formwork bases, two side forms, a top formwork, two movable corner forms, a longitudinal stabilizing truss, and a transverse stabilizing truss. The wheels are respectively installed at the bottom of the two side formwork bases. The lower ends of the two side forms are respectively installed on the two side formwork bases. The upper ends of the two side forms are movably and fixedly connected to the left and right ends of the top formwork through the two movable corner forms. Each side formwork has a set of transverse stabilizing trusses on its inner side, and the two sets of transverse stabilizing trusses are connected by several first telescopic rods. The side formwork bases are also provided with longitudinal stabilizing trusses to fix the side forms. The outer wall of the movable corner formwork has a chamfer that matches the chamfer of the inner wall of the pipe section top plate. The wheels are omnidirectional wheels that can move in any direction.

2. The construction method of the high-pressure water-passing rectangular jacking pipe section composite connection structure as described in claim 1, characterized in that: In the portal-shaped movable template trolley, the movable corner mold and the top mold are movably fixedly connected in the following manner: The movable corner mold has a sliding plate in the lateral direction. The upper surface of the sliding plate slides in contact with the lower surface of the top mold. The sliding plate is provided with several temporary fastening bolts. The top mold is provided with several fastening screw holes that match the temporary fastening bolts. A second telescopic rod is also provided between the movable corner mold and the top mold. When the second telescopic rod extends or retracts, the minimum contact length between the sliding plate and the top mold is 0.3-0.5 times the maximum contact length between the sliding plate and the top mold. By adjusting the fastening position of the temporary fastening bolts and the length of the second telescopic rod, a movable fixed connection between the movable corner mold and the top mold can be achieved. The connection method between the two side molds and the movable corner mold is the same as the connection method between the top mold and the movable corner mold.

3. The construction method of the high-pressure water-passing rectangular jacking pipe section composite connection structure as described in claim 1, characterized in that: In S1, during the prefabrication of pipe sections, several pre-embedded bolts are provided on the annular protrusions of the top plate and the two side plates of the pipe section near the two ends of the annular protrusions. The distance between the pre-embedded bolts and the two ends of the annular protrusions is 10-30cm. One end of the pre-embedded bolt is exposed on the inner circumference of the pipe section, with an exposed length of 2-10cm. In the portal-shaped movable template trolley, several nuts matching the pre-embedded bolts of the pipe section are provided on the two side molds and the top mold.

4. The construction method of the high-pressure water-passing rectangular jacking pipe section composite connection structure as described in claim 1, characterized in that: In the portal-shaped movable formwork trolley, at least one water-stop rubber strip is pasted around the perimeter of the two side forms and the top formwork to cover the area of ​​the post-poured reinforced concrete side slabs and top slabs.

5. The construction method of the high-pressure water-passing rectangular jacking pipe section composite connection structure as described in claim 1, characterized in that: In S1, during the prefabrication of pipe sections, a vent pipe is suspended and installed at the bottom of the top plate of the pipe section. The air inlet of the vent pipe is located in the annular cavity between the annular bosses of two adjacent pipe sections, and the air outlet of the vent pipe is exposed on the inner circumference of the pipe section. The exposed length of the vent pipe is 10-30cm. The top mold of the portal-shaped movable template trolley is provided with a vent pipe reserved hole with a diameter matching the vent pipe for the vent pipe to pass through. In S4, the two side slabs and the top slab of the post-cast reinforced concrete are poured in the following manner: Pumped concrete was used to pour the two side plates and the top plate of the post-cast reinforced concrete from bottom to top. When the cement slurry flowed down the vent pipe, the vent pipe was closed, and the concrete was poured according to the concrete pouring volume calculated by formula (1) until the top plate was full. （1）； In the formula: V This refers to the amount of concrete poured after the vent pipe is sealed. L This refers to the longitudinal length of the post-cast reinforced concrete. B The width of the pipe section; ζ This is the reduction factor.

6. The construction method of the high-pressure water-passing rectangular jacking pipe section composite connection structure as described in claim 1, characterized in that: A traction device is provided in front of the portal-shaped mobile template trolley and connected to the portal-shaped mobile template trolley.

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