Energy duct piece prefabrication production process

Abstract

The invention provides an energy duct piece prefabrication production process, and belongs to the technical field of shield engineering construction in urban rail transit. In order to solve the problems that a heat source generated in the subway operation stage easily causes underground space thermal pollution, traditional ventilation and heat extraction waste energy, and a traditional ground heat exchanger is large in construction difficulty and high in manufacturing cost, the technology comprises the steps that a capillary network heat exchanger is pre-buried in a prefabricated tube piece; the waste heat in the tunnel is conducted to the building on the ground for heating through material field storage, capillary network heat exchanger installation, duct piece pouring maintenance, leak detection test, duct piece splicing, energy duct piece and main pipe connection and a heat pump unit. Efficient energy utilization, energy conservation and emission reduction are achieved, construction operation is simple, duct piece forming quality is stable, underground heat pollution can be solved, heat balance of the tunnel environment and urban underground space is improved, and operation and maintenance cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of tunnel boring machine (TBM) construction technology in urban rail transit, specifically to a prefabrication process for energy tunnel segments. Background Technology

[0002] With the rapid development of urban underground transportation, the number of underground tunnels constructed using the shield tunneling method has increased. During the subway operation phase, a large amount of heat is generated. After being absorbed by the surrounding rock of the tunnel, this heat accumulates, causing thermal pollution in the underground space and seriously affecting the efficient and safe operation of the subway.

[0003] To address thermal pollution, traditional methods employ piston ventilation or mechanical ventilation to expel heat from tunnels, but this results in significant energy waste. In recent years, some projects have attempted to integrate buried pipe heat exchangers from traditional ground-source heat pump systems with the tunnel structure to extract waste heat for heating above-ground buildings. While this achieves efficient energy utilization and improves the tunnel environment, traditional buried pipes suffer from large diameters, large turning radii, and require substantial construction space, leading to high costs, construction difficulties, and slow progress in practical projects, making them unsuitable for metro tunnel engineering. Therefore, there is an urgent need for a prefabrication and manufacturing process for energy-efficient tunnel segments that can efficiently utilize waste heat from metro operations, is easy to construct, and has strong versatility. Summary of the Invention

[0004] The present invention aims to solve the problems mentioned in the background art by providing a prefabrication process for energy tube segments.

[0005] The specific technical solution is as follows: A prefabrication process for energy tube segments includes the following steps in sequence: material storage upon arrival, assembly and fixing of a capillary network heat exchanger, casting and curing of the tube segments, leak testing, segment assembly, network connection, and heat exchange operation. The process utilizes a capillary network, outlet manifold, inlet manifold, manifold, outlet, reinforcing cage, tube segment body, main network, and heat pump unit. The capillary network heat exchanger consists of a capillary network, outlet manifold, inlet manifold, manifold, and outlet. Both ends of the capillary network are connected to the inlet water... The manifold and outlet manifold are connected, and the manifold is connected to the inlet manifold and outlet manifold respectively. The outlet is located at the end of the outlet manifold away from the capillary network. The capillary network heat exchanger and the reinforcing cage are fixed together and placed in the segment mold. Concrete is poured to form the segment body. After the segment body is formed, the end of the inlet manifold away from the capillary network and the outlet are connected to the main pipeline network. The main pipeline network is connected to the heat pump unit. The heat pump unit is used to connect to the above-ground buildings to conduct heat from the tunnel to the above-ground buildings.

[0006] As a preferred scheme of the present application, in the material storage step, the capillary tube network, the water outlet header, the water inlet header, the header and the matching pipe material and pipe fittings need to be transported with packaging, and throwing, dropping, rolling and dragging are prohibited during transportation and handling to avoid oil and chemical contamination, and the package cannot be opened without inspection; the storage area is a well-ventilated warehouse or shed, and open-air stacking is prohibited, and the ambient temperature of the storage area is not less than 5℃; the capillary tube network, the water outlet header, the water inlet header and the header are stored in boxes on shelves or flat ground, and the stacking height is not more than 1.5m, the matching pipe material is horizontally stacked, the storage area is far away from oil, chemicals, heat sources and fire sources, fire prevention measures are taken, the access channel is free of sharp objects, and the first-in first-out principle is implemented.

[0007] As a preferred scheme of the present application, in the capillary tube network heat exchanger assembly and fixing step, the capillary tube network is aligned and positioned with the same type of reinforcement cage, and the capillary tube network is tightly attached to the outer arc surface of the reinforcement cage; the capillary tube network is fixed by steel wire mesh straps with a spacing of 4cm; the end of the water inlet header away from the capillary tube network and the water outlet are respectively inserted into rubber positioners for fixation, and the end of the water inlet header away from the capillary tube network and the water outlet are both provided with sealing plugs; the material of the capillary tube network is subjected to metal passivation treatment, and the installation and construction environment temperature is not less than 5℃, and when the ambient temperature is between 5℃ and 10℃, heating measures need to be taken to make the ambient temperature higher than 10℃.

[0008] As a preferred scheme of the present application, in the pipe segment pouring and curing step, the cleanliness of the pipe segment mold and the thickness of the reinforcement cage protective layer need to be checked before pouring; C50 concrete is used for layer-by-layer pouring through an attached vibrator, and during the pouring process, it is ensured that the capillary tube network, the water outlet header, the water inlet header and the header are completely covered by the concrete without loosening; immediately after pouring, the outer arc surface of the pipe segment body is scraped flat and compacted; if the capillary tube network, the water outlet header, the water inlet header or the header is displaced during pouring, pouring needs to be paused, the displacement direction and the displacement amount are recorded, the positions of the reinforcement cage and the capillary tube network heat exchanger are corrected and then re-fixed, and then pouring continues.

[0009] As a preferred scheme of the present application, the pipe segment curing adopts steam curing or water curing; during steam curing, the heating rate is not more than 15℃ per hour, the temperature is raised to 60℃ and then constant temperature curing is performed, the constant temperature curing environment humidity is not less than 90%, and the cooling rate is not more than 20℃ per hour, and the pipe segment body demolding strength is not less than 20MPa; during water curing, the pipe segment body is immersed in water for 7 to 14 days, the water temperature and the pipe segment body temperature difference are measured regularly to ensure that the temperature difference is not more than 20℃, when the temperature difference is greater than 20℃, the water circulation system is started to adjust the water temperature, and the end of the water inlet header away from the capillary tube network and the water outlet are both provided with protective caps.

[0010] As a preferred scheme of the present application, the leakage detection test step comprises three times of leakage detection: the first time is water pressure leakage detection test after the capillary network heat exchanger is fixed with the reinforcement cage, the sampling ratio of the water pressure leakage detection test is not less than 1%, and water is injected into the water inlet header during the test to observe whether the capillary network, the water outlet header, the header and the water outlet are leaked; the second time is air tightness test after the segment body is prefabricated; and the third time is air tightness test after the segment body arrives at the site; the test pressure of the air tightness test is all 0.8 MPa, and gas is introduced into the water inlet header during the test to monitor the pressure change of the water outlet and the header.

[0011] As a preferred scheme of the present application, in the segment assembling step, segment selection is performed first, and the design axis, the shield tail gap and the stroke difference of the push oil cylinder are comprehensively considered during the selection; a staggered joint assembling method is adopted to install the segment body block by block from bottom to top; the capping block in the segment body is first pushed into two-thirds of the width in the radial direction, and then inserted longitudinally; the shield tail sundries need to be cleaned before and after assembling, the quality of the segment body water stop strip is checked, and the protective cap is installed at the end of the water inlet header away from the capillary network and the water outlet immediately after assembling, and the push oil cylinder at the non-segment installation position is prohibited from being retracted simultaneously with the push oil cylinder at the segment installation position.

[0012] As a preferred scheme of the present application, the bolts are fastened synchronously during segment assembling, and the bolt fastening follows the three-time re-tightening principle: the first re-tightening is performed when the lower ring push stroke is more than half; the second re-tightening is performed after the segment body of the lower ring is assembled; and the third re-tightening is performed after the segment body is out of the shield tail, and the torque of each bolt fastening meets the design requirement, so as to ensure the stability of the segment body splicing and avoid damage of the capillary network, the water outlet header, the water inlet header or the header due to assembling stress.

[0013] As a preferred scheme of the present application, the outer wall of the water inlet header and the water outlet header and the concrete layer cast with the segment body are provided with a water stop sealing gasket, a butyl rubber waterproof section is pasted outside the water stop sealing gasket, and a kraft paper protection layer is arranged outside the butyl rubber waterproof section, so as to realize waterproof sealing between the water inlet header, the water outlet header and the concrete layer, and prevent water from penetrating into the capillary network or the header during use of the segment body.

[0014] As a preferred scheme of the present application, if the capillary network heat exchanger is found to leak in the leak detection test, the repair method is as follows: when the capillary network leaks, the leaking section is cut off, the cut is kept flat, a special hot melt welding machine is used to butt joint the new pipe section, and after cooling, the flatness of the weld is checked; when the joint of the header and the water inlet header or the water outlet header leaks, the joint is disassembled and the butyl rubber sealing gasket is replaced, and the joint is tightened again; when the water outlet leaks, the sealing plug is replaced and the rubber positioner is fixed again; after the repair is completed, a pressure test is carried out, the pressure holding pressure is 0.6 MPa, the pressure holding time is not less than 15 minutes, the pressure drop during pressure holding is not more than 3%, and the repair area is additionally reinforced with stainless steel clamps, the spacing of the stainless steel clamps is not more than 10 cm.

[0015] The present application has the following beneficial effects: 1. Energy utilization and energy saving and emission reduction: The present application can effectively collect the waste heat generated by subway operation and transfer it to the above-ground building for heating, avoiding the energy waste of traditional ventilation methods, while reducing the energy consumption of the traditional heating system of the above-ground building, realizing efficient energy utilization and energy saving and emission reduction.

[0016] 2. Improved construction and structural adaptability: The capillary network 1 is small in volume and flexible in installation, and is fixed with a reinforcement cage and then poured to form a pipe body, so that the heat exchange system is integrated with the tunnel structure, without the need for additional construction space, solving the problem of large pipe diameter and high construction difficulty of traditional buried pipes; the pipe assembly process is basically the same as that of ordinary pipes, without the need for additional training of construction personnel, reducing the construction difficulty and improving the construction efficiency, while the pipe body forming quality is equivalent to that of ordinary pipes, ensuring the stability of the tunnel structure.

[0017] 3. System reliability and durability guarantee: The specification requirements for material procurement and storage avoid damage to the capillary network, water outlet header, water inlet header and header during transportation and storage; metal passivation treatment during installation prolongs the service life of the capillary network, and the setting of the water stop sealing gasket and the butyl rubber waterproof section prevents water from seeping into the damaged parts; multiple leak detection tests and targeted repair measures ensure that the capillary network heat exchanger does not leak, improve the sealing and reliability of the heat exchange system, and reduce the probability of failure.

[0018] 4. Environmental and operational improvement: The capillary network 1 absorbs tunnel waste heat to avoid heat accumulation, solves the problem of environmental heat pollution in underground engineering, reduces the damage of waste heat to equipment and facilities in the tunnel, reduces the frequency of equipment maintenance and replacement, prolongs the service life of the equipment, and saves operation and maintenance costs; at the same time, it avoids the influence of tunnel heat accumulation on surrounding soil, groundwater and other environmental elements, maintains the thermal balance of urban underground space, improves the overall thermal environment of the city, and improves the quality of residents' life.

[0019] 5. versatility and economy: the process is suitable for different strata (soft soil stratum, rock stratum) of tunnel engineering, and the installation scheme of capillary network 1 can be adjusted according to the stratum condition, which has wide versatility; no additional buried pipe system needs to be built, the overall cost of the project is reduced, and the energy and maintenance cost expenditure is reduced in subsequent operation, which has technical and economic advantages. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 is the energy pipe lining block diagram of the present application; Fig. 2 is the energy pipe unfolding plan view of the present application; Fig. 3 is the energy pipe section view of the present application.

[0021] In the drawings: 1, capillary network; 2, water outlet header; 3, water inlet header; 4, header; 5, water outlet. DETAILED DESCRIPTION

[0022] The technical solutions of the present application will be further described below in combination with the drawings and through specific embodiments.

[0023] Among them, the drawings are only used for example explanation, and the representation is only a schematic diagram, not a real object diagram, and cannot be understood as a limitation of the present application; in order to better illustrate the embodiments of the present application, some components of the drawings will be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some known structures and their descriptions in the drawings can be omitted.

[0024] The same or similar reference numerals in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it should be understood that if the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationship in the drawings are only used for example explanation, and cannot be understood as a limitation of the present application, for those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0025] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] Example The energy segment prefabrication production process provided in this embodiment, such as Figs. 1-3 As shown, the process steps sequentially include material storage upon arrival, capillary heat exchanger assembly and fixing, tube segment casting and curing, leak testing, tube segment assembly, pipe network connection, and heat exchange operation. It is equipped with capillary network 1, outlet manifold 2, inlet manifold 3, manifold 4, outlet 5, reinforcing cage, tube segment body, main pipe network, and heat pump unit. The capillary heat exchanger consists of capillary network 1, outlet manifold 2, inlet manifold 3, manifold 4, and outlet 5. Both ends of capillary network 1 are connected to inlet manifold 3 and outlet manifold 4, respectively. Water manifold 2 is connected, and manifold 4 is connected to inlet manifold 3 and outlet manifold 2 respectively. Outlet 5 is located at the end of outlet manifold 2 away from capillary network 1. After the capillary network heat exchanger and the steel cage are fixed, they are placed together in the segment mold and concrete is poured to form the segment body. After the segment body is formed, the end of inlet manifold 3 away from capillary network 1 and outlet 5 are connected to the main pipeline network respectively. The main pipeline network is connected to the heat pump unit. The heat pump unit is used to connect to the above-ground building to conduct heat in the tunnel to the above-ground building.

[0027] This process clarifies the connection relationships between core steps and supporting components. A capillary heat exchanger is constructed using capillary network 1, outlet manifold 2, inlet manifold 3, manifold 4, and outlet 5. After being fixed to a reinforcing cage, it is cast into a tube segment body. This body is then connected to the main pipeline network and heat pump unit via inlet manifold 3 and outlet 5, ultimately achieving heat transfer from the tunnel to the above-ground buildings. This solution effectively utilizes waste heat generated during subway operation, replacing traditional buried pipe heat exchange methods and solving the problem of poor compatibility between traditional buried pipes and tunnel structures. Simultaneously, by relying on the tube segment body, the heat exchange system is integrated with the tunnel structure, ensuring stable integration of the heat exchange system into the tunnel project and achieving energy-efficient utilization and energy conservation and emission reduction.

[0028] Specifically, in the present embodiment, in the material storage step, the capillary tube network 1, the water outlet header 2, the water inlet header 3, the header 4 and the matching pipe material and pipe fittings need to be transported with packaging, and throwing, dropping, rolling and dragging are prohibited during transportation and handling to avoid oil and chemical contamination. The storage area is a well-ventilated warehouse or shed, and open-air stacking is prohibited. The ambient temperature of the storage area is not less than 5°C. The capillary tube network 1, the water outlet header 2, the water inlet header 3 and the header 4 are stored in boxes on shelves or flat ground, and the stacking height is not more than 1.5m. The matching pipe material is horizontally stacked. The storage area is away from oil, chemicals, heat sources and fire sources. Fire prevention measures are taken. The access channel is free of sharp objects, and the first-in-first-out principle is implemented. The process makes clear requirements for the transportation and storage of the capillary tube network 1, the water outlet header 2, the water inlet header 3, the header 4 and the matching pipe material and pipe fittings. By transporting with packaging, damage or contamination of the components can be avoided. Relying on the well-ventilated and temperature-controlled storage area and the standardized stacking method can protect the components. This can prevent damage, deformation of the components due to collision, pollution, unsuitable temperature and humidity or improper stacking during transportation and storage, and ensure that the capillary tube network 1, the water outlet header 2, the water inlet header 3 and the header 4 used in subsequent construction are in good condition, laying a foundation for stable installation and operation of the heat exchange system.

[0029] Specifically, in the present embodiment, in the material storage step, the capillary tube network 1, the water outlet header 2, the water inlet header 3, the header 4 and the matching pipe material and pipe fittings need to be transported with packaging, and throwing, dropping, rolling and dragging are prohibited during transportation and handling to avoid oil and chemical contamination. The storage area is a well-ventilated warehouse or shed, and open-air stacking is prohibited. The ambient temperature of the storage area is not less than 5°C. The capillary tube network 1, the water outlet header 2, the water inlet header 3 and the header 4 are stored in boxes on shelves or flat ground, and the stacking height is not more than 1.5m. The matching pipe material is horizontally stacked. The storage area is away from oil, chemicals, heat sources and fire sources. Fire prevention measures are taken. The access channel is free of sharp objects, and the first-in-first-out principle is implemented. The process makes clear requirements for the transportation and storage of the capillary tube network 1, the water outlet header 2, the water inlet header 3, the header 4 and the matching pipe material and pipe fittings. By transporting with packaging, damage or contamination of the components can be avoided. Relying on the well-ventilated and temperature-controlled storage area and the standardized stacking method can protect the components. This can prevent damage, deformation of the components due to collision, pollution, unsuitable temperature and humidity or improper stacking during transportation and storage, and ensure that the capillary tube network 1, the water outlet header 2, the water inlet header 3 and the header 4 used in subsequent construction are in good condition, laying a foundation for stable installation and operation of the heat exchange system.

[0030] Specifically, in the present embodiment, in the segment pouring and curing step, the segment mold cleanliness and the reinforcement cage protective layer thickness are checked before pouring; C50 concrete is used, and the concrete is poured in layers through an attached vibrator, and during pouring, the capillary tube network 1, the water outlet header 2, the water inlet header 3, and the header 4 are completely covered by the concrete and are not loose; immediately after pouring, the outer arc surface of the segment body is scraped flat and compacted; if the capillary tube network 1, the water outlet header 2, the water inlet header 3, or the header 4 is displaced during pouring, pouring is suspended, the displacement direction and the displacement amount are recorded, the reinforcement cage and the capillary tube network heat exchanger position are corrected, and then pouring is continued after re-fixing. In the segment pouring and curing step, the mold and the reinforcement cage protective layer thickness are checked before pouring, the pouring is performed in layers, the displaced parts are corrected in time, and the capillary tube network 1, the water outlet header 2, the water inlet header 3, and the header 4 are completely covered by the concrete and are not loose. The pre-pouring inspection can avoid the influence of mold impurities or insufficient protective layer thickness on the segment body quality and part installation; the layer-by-layer pouring allows the concrete to fully wrap the parts, preventing the parts from being exposed or loose; the displacement correction can avoid the displacement of the parts, which may cause poor heat exchange path in the subsequent process, ensuring the structural stability of the segment body and the accurate installation position of the capillary tube network heat exchanger in the segment body, and ensuring the normal operation of the heat exchange system in the subsequent process.

[0031] Specifically, in the present embodiment, the segment curing is performed by steam curing or water curing; when the segment is cured by steam, the temperature rise rate is not more than 15°C per hour, the temperature is raised to 60°C, and then the temperature is kept constant, the constant temperature curing environment humidity is not less than 90%, the temperature drop rate is not more than 20°C per hour, and the segment body demolding strength is not less than 20 MPa; when the segment is cured in water, the segment body is immersed in water for 7 to 14 days, the water temperature and the segment body temperature difference are measured regularly to ensure that the temperature difference is not more than 20°C, and when the temperature difference is greater than 20°C, the water circulation system is started to adjust the water temperature, and the water inlet header 3 far from the capillary tube network 1 and the water outlet 5 are both installed with protective caps. The process uses steam curing or water curing for segment curing, and proposes requirements for curing parameters, temperature difference control, and protection of the water inlet header 3 and the water outlet 5. Reasonable curing methods can promote the segment body strength to meet the standard, avoid cracking and insufficient strength of the segment body due to improper curing, and ensure the stability of the segment body structure; temperature difference control can prevent the segment body from being damaged due to sudden temperature changes; and the installation of protective caps on the water inlet header 3 and the water outlet 5 can prevent water or impurities from entering the inside of the parts during the curing process, protect the capillary tube network 1, the header 4, and other parts from being damaged, and ensure the normal operation of the heat exchange system in the subsequent process.

[0032] Specifically, in the present embodiment, the leakage detection test step includes three leak detection tests: the first is a water pressure leakage detection test after the capillary network heat exchanger is fixed with the reinforcement cage, the sampling ratio of the water pressure leakage detection test is not less than 1%, and during the test, water is injected into the water inlet header 3, and whether the capillary network 1, the water outlet header 2, the header 4 and the water outlet 5 leak is observed; the second is a gas tightness test after the segment body is prefabricated; the third is a gas tightness test after the segment body arrives at the site; the test pressure of the gas tightness test is all 0.8 MPa, and during the test, gas is introduced into the water inlet header 3, and the pressure change of the water outlet 5 and the header 4 is monitored. Through the three leakage detection tests (water pressure leakage detection after the capillary network heat exchanger is fixed, gas tightness test after the segment body is prefabricated and arrives at the site), leakage inspection is carried out on the water inlet header 3, the capillary network 1, the water outlet header 2, the header 4, and the water outlet 5. Multiple leakage detection can comprehensively check the sealing condition of each part and the connecting part of the heat exchange system, and can find the possible leakage problems of the capillary network 1, the water outlet header 2, the water inlet header 3, the header 4, and the water outlet 5 in advance, so as to avoid the heat exchange system from being damaged due to leakage in subsequent use, and to ensure the sealing and reliability of the heat exchange system.

[0033] Specifically, in the present embodiment, in the segment assembly step, the segment selection is performed first, and the design axis, the shield tail gap and the stroke difference of the push oil cylinder are considered comprehensively during the selection; a staggered joint assembly method is adopted, and the segment body is installed block by block from bottom to top; the top block in the segment body is first pushed into two-thirds of the width in the radial direction, and then inserted longitudinally; the shield tail sundries need to be cleaned before and after assembly, the quality of the water stop strip pasting of the segment body is checked, and the protective cap is installed on the end of the water inlet header 3 away from the capillary network 1 and the water outlet 5 immediately after assembly, and the push oil cylinder at the non-segment installation position and the push oil cylinder at the segment installation position are prohibited from being retracted at the same time. The segment assembly link ensures the stability of the segment body joint by reasonable selection, staggered joint assembly, cleaning of sundries, checking of water stop strips, installation of protective caps and control of oil cylinder operation. The selection and staggered joint assembly can improve the overall structural stability of the segment body and avoid excessive joint gap; cleaning of sundries and checking of water stop strips can ensure the sealing of the joint of the segment body and prevent external water from entering; installation of protective caps on the water inlet header 3 and the water outlet 5 can prevent sundries from entering the internal components; and the prohibition of simultaneous retraction of specific oil cylinders can prevent the segment body and the internal capillary network 1, water outlet header 2, water inlet header 3 and header 4 from being damaged due to improper stress, and ensure the integrity of the segment structure and the heat exchange system.

[0034] Specifically, in the present embodiment, the pipe piece is assembled synchronously with the fastening of the bolt, and the bolt fastening follows the principle of three times of re-tightening: the first re-tightening is performed when the lower ring pushing distance is more than half; the second re-tightening is performed after the lower ring pipe piece body is assembled; the third re-tightening is performed after the pipe piece body is out of the shield tail, and the torque of each bolt fastening meets the design requirements, ensuring the stability of the pipe piece body splicing, avoiding the damage of the capillary tube network 1, the water outlet header 2, the water inlet header 3 or the header 4 due to the stress of assembly. The operation mode of three times of re-tightening of the bolt can ensure the connection strength of the pipe piece body splicing place, avoid the increase of the splicing gap or the structure displacement of the pipe piece body due to the bolt loosening in the long-term use process. The stable splicing of the pipe piece body can prevent the capillary tube network 1, the water outlet header 2, the water inlet header 3 and the header 4 inside from being damaged due to the structure loosening, extrusion or pulling, ensure the structural stability of the pipe piece body and the integrity of the heat exchange system, and prolong the service life of the pipe piece and the heat exchange system.

[0035] Specifically, in the present embodiment, the water stop sealing gasket is arranged between the outer wall of the water inlet header 3 and the water outlet header 2 and the concrete layer of the pipe piece body, the butyl rubber waterproof section is pasted outside the water stop sealing gasket, and the kraft paper protection layer is arranged outside the butyl rubber waterproof section, so as to realize the waterproof sealing between the water inlet header 3 and the water outlet header 2 and the concrete layer, prevent the water from penetrating into the capillary tube network 1 or the header 4 during the use of the pipe piece body. Arranging the water stop sealing gasket, the butyl rubber waterproof section and the kraft paper protection layer between the outer wall of the water inlet header 3 and the water outlet header 2 and the concrete layer can effectively block the water from penetrating into the gap between the components and the concrete layer from the outside of the pipe piece body. This can prevent the penetrated water from damaging the capillary tube network 1 and the header 4, avoid the failure of the heat exchange system due to water inlet, and at the same time protect the internal structure of the pipe piece body from water erosion, improve the waterproof performance and durability of the pipe piece body and the heat exchange system.

[0036] Specifically, in the present embodiment, if leakage of the capillary network heat exchanger is found in the leakage detection test, the repair method is as follows: when the capillary network 1 leaks, the leaking section is cut off, the cut is kept flat, a special hot melting welding machine is used to butt joint the new pipe section, and the flatness of the welded joint is checked after cooling; when the joint of the header 4 and the water inlet header 3 or the water outlet header 2 leaks, the joint is disassembled and the butyl rubber sealing gasket is replaced, and the joint is tightened again; when the water outlet 5 leaks, the sealing plug is replaced and the rubber positioner is fixed again; after the repair is completed, a pressure retention test is carried out, the pressure retention pressure is 0.6 MPa, the pressure retention time is not less than 15 minutes, the pressure drop during pressure retention is not more than 3%, and stainless steel clamps are additionally added for reinforcement in the repaired area, the distance between the stainless steel clamps is not more than 10 cm. Different repair methods are proposed for different parts (capillary network 1 leakage, header 4 joint leakage, water outlet 5 leakage), and the repair effect is ensured through pressure retention test and reinforcement operation. The targeted repair can accurately solve the leakage problem of each part, the pressure retention test can verify the sealing performance after repair, and the reinforcement operation can improve the structural stability of the repaired part, ensuring that the capillary network 1, the header 4, the water outlet 5 and other parts can restore normal use function after repair, avoiding the continuous impact of leakage problem on the operation of the heat exchange system, and ensuring the reliability and service life of the heat exchange system.

[0037] Working principle: The process mainly constructs a tunnel waste heat recovery and utilization system by pre-embedding a capillary network heat exchanger composed of a capillary network 1, a water outlet header 2, a water inlet header 3, a header 4, and a water outlet 5 in the pipe body.

[0038] The capillary network 1, as the core component of heat exchange, communicates with the water inlet header 3 and the water outlet header 2, the header 4 connects the water inlet header 3 and the water outlet header 2, forming a complete heat exchange flow channel; after the capillary network heat exchanger is fixed with the reinforcement cage, the pipe body is formed by pouring concrete, making the heat exchange system integrated with the tunnel structure.

[0039] The waste heat generated by subway operation will be transferred to the inside of the tunnel, the capillary network 1 in the pipe body absorbs these waste heat, the heat is transferred to the water inlet header 3 through the capillary network 1, then distributed to the water outlet header 2 through the header 4, and finally delivered to the main pipe network through the water outlet 5; the main pipe network delivers the medium carrying waste heat to the heat pump unit, which processes the heat and transfers it to the building above ground, realizing the conversion of tunnel waste heat to heating for buildings above ground, while avoiding heat accumulation in the tunnel.

[0040] Implementation method: 1. Material approach and storage: Capillary tube network 1, water outlet header 2, water inlet header 3, header 4, water outlet and matching pipe materials, pipe fittings need to be transported with packaging, and throwing, throwing, rolling, dragging during transportation and handling is prohibited to avoid oil pollution and chemical contamination. Do not open without inspection. When stored, it needs to be placed in a well-ventilated warehouse or shed. Prohibit open-air stacking. The storage area is away from oil, chemicals, heat sources and fire sources. Take fire prevention measures, and the ambient temperature is not lower than the specified requirement; Capillary tube network 1, water outlet header 2, water inlet header 3, header 4 are stored in boxes on shelves or flat ground. The matching pipe materials are horizontally stacked. The first-in-first-out principle is implemented to ensure that the storage and retrieval channel is free of sharp objects.

[0041] 2. Capillary tube network heat exchanger installation: Align the L1 / L2 / B1 / B3 model capillary tube network 1 with the same model L1 / L2 / B1 / B3 reinforcement cage, make the capillary tube network 1 tightly adhere to the outer arc surface of the reinforcement cage, and evenly fix the capillary tube network 1 with a steel wire mesh strap at an interval of 4 cm; Insert the end of the water inlet header 3 away from the capillary tube network 1 and the water outlet 5 into the pre-installed rubber positioner to fix it. Check if the sealing plug and waterproof measures are intact; Perform metal passivation treatment on the capillary tube network 1, and the construction environment temperature needs to meet the requirements (do not construct below 5℃, take warming measures when the temperature is between 5℃ and 10℃), and finally perform a water pressure leak detection test to ensure that there is no leakage before moving on to the next process.

[0042] 3. Paving and curing of pipe segments: Check the cleanliness of the mold and the thickness of the reinforcement cage protective layer before paving, place the reinforcement cage with pre-embedded capillary tube network heat exchanger into the mold and fix it; Use an attached vibrator to pave the concrete layer by layer to ensure that the capillary tube network 1, water outlet header 2, water inlet header 3, and header 4 are completely covered by the concrete without looseness. Immediately scrape the outer arc surface of the pipe segment body after paving and compact it. Curing can be done by steam curing or water curing. Control temperature and humidity and temperature difference during the curing process. Install protective caps on the water inlet header 3 and water outlet 5 during water curing.

[0043] 4. Leak detection test: After the energy pipe segment is precast and arrives at the site, respectively, carry out air tightness test to check whether the capillary tube network 1, water outlet header 2, water inlet header 3, header 4, and water outlet 5 are leaking; If leakage is found, take corresponding repair measures for different parts (such as cutting off the leakage section and connecting a new pipe section for capillary tube network 1 leakage, replacing the sealing gasket for header 4 joint leakage, etc.), and perform a pressure test after repair.

[0044] 5. Segment assembly: First, select the type of segment, considering the design axis, shield tail gap and the stroke difference of the push cylinder; adopt staggered joint assembly method, install from bottom to top, insert the top block F into the tunnel body first, then push it into the tunnel body; clean the shield tail before and after assembly, check the quality of the segment water stop strip, and install the protective cap on the water inlet header 3 and the water outlet 5 immediately after assembly; tighten the bolts simultaneously during assembly, follow the three times retightening principle, and prohibit the simultaneous contraction of the push cylinder at non-segment installation position and segment installation position.

[0045] 6. Pipe network connection and heat exchange operation: After the tunnel is connected and the segment is installed, connect the water inlet header 3 and the water outlet 5 of the capillary tube network heat exchanger in the segment body to the main pipe network, and perform water pressure test to verify effectiveness; then connect the main pipe network to the heat pump unit, and when the subway is in operation, the capillary tube network 1 can absorb the waste heat of the tunnel, which is transmitted to the heat pump unit through the water inlet header 3, the header 4, the water outlet header 2, the water outlet 5 and the main pipe network, and then the heat pump unit conducts heat to the above-ground building to achieve heating.

[0046] The technical effects are as follows: 1. Energy utilization and energy saving and emission reduction: The process replaces the traditional buried pipe by pre-embedding the capillary tube network heat exchanger composed of capillary tube network 1, water outlet header 2, water inlet header 3, header 4 and water outlet 5 in the segment body, which can effectively collect the waste heat generated by subway operation and transfer it to the above-ground building for heating, avoiding energy waste in traditional ventilation methods, reducing energy consumption of traditional heating systems of above-ground buildings, and realizing efficient energy utilization and energy saving and emission reduction.

[0047] 2. Improved construction and structural adaptability: The capillary tube network 1 is small in size and flexible in installation, and is fixed with the reinforcement cage and then poured to form the segment body, making the heat exchange system integrated with the tunnel structure, without the need for additional construction space, solving the problem of large diameter and difficult construction of traditional buried pipes; the segment assembly process is basically the same as that of ordinary segments, without the need for additional training of construction personnel, reducing construction difficulty and improving construction efficiency, while the segment body has the same quality as ordinary segments, ensuring the stability of the tunnel structure.

[0048] 3. System reliability and durability: The specification requirements for material procurement and storage avoid damage to the capillary tube network 1, water outlet header 2, water inlet header 3 and header 4 during transportation and storage; metal passivation treatment during installation prolongs the service life of the capillary tube network 1, and the setting of water stop sealing gasket and butyl rubber waterproof section prevents water from seeping into the components; multiple leak detection tests and targeted repair measures ensure that the capillary tube network heat exchanger has no leakage, improving the sealing and reliability of the heat exchange system and reducing the probability of failure.

[0049] 4. Environment and operation improvement: The capillary network 1 absorbs the tunnel waste heat to avoid heat accumulation, solves the problem of underground engineering environmental heat pollution, reduces the damage of waste heat to equipment and facilities in the tunnel, reduces the frequency of equipment maintenance and replacement, prolongs the service life of equipment, saves operation and maintenance cost; At the same time, it avoids the influence of tunnel heat accumulation on surrounding soil, underground water and other environmental elements, maintains the heat balance of urban underground space, improves the overall thermal environment of the city, and improves the quality of life of residents.

[0050] 5. Universality and economy: The process is suitable for tunnel engineering of different strata (soft soil stratum, rock stratum), and the installation scheme of the capillary network 1 can be adjusted according to the stratum condition, which has wide universality; without additional construction of buried pipe system, reduces the overall cost of the project, and reduces the energy and maintenance cost in subsequent operation, with technical and economic advantages.

[0051] The above is only the preferred embodiment of the present application, and does not limit the implementation and protection scope of the present application. For those skilled in the art, it should be realized that any equivalent replacement and obvious change made by applying the content of the present application should be included in the protection scope of the present application.

Claims

1. A process for the prefabricated production of energy ducts, characterized in that, The process steps include material storage, capillary tube network heat exchanger assembly and fixation, pipe piece pouring and curing, leakage test, pipe piece assembly, pipe network connection and heat exchange operation in sequence, and are matched with capillary tube network (1), water outlet header (2), water inlet header (3), header (4), water outlet (5), reinforcement cage, pipe piece body, main pipe network and heat pump unit; the capillary tube network heat exchanger is composed of capillary tube network (1), water outlet header (2), water inlet header (3), header (4) and water outlet (5), the two ends of the capillary tube network (1) are communicated with the water inlet header (3) and the water outlet header (2) respectively, the header (4) is connected with the water inlet header (3) and the water outlet header (2) respectively, and the water outlet (5) is arranged at one end of the water outlet header (2) away from the capillary tube network (1); the capillary tube network heat exchanger and the reinforcement cage are fixed together in the pipe piece mold after the capillary tube network heat exchanger is fixed, and the pipe piece body is formed by pouring concrete; after the pipe piece body is formed, one end of the water inlet header (3) away from the capillary tube network (1) and the water outlet (5) are communicated with the main pipe network respectively, the main pipe network is connected with the heat pump unit, and the heat pump unit is used for connecting with the aboveground building to conduct the heat in the tunnel to the aboveground building.

2. The energy tube segment pre-production process of claim 1, wherein, In the material storage step, the capillary tube network (1), the water outlet header (2), the water inlet header (3), the header (4) and the matched pipe material and pipe fitting need to be transported with packaging, and throwing, dropping, rolling and dragging are prohibited in the transportation and carrying process to avoid oil stain and chemical pollution, and the packaging cannot be opened without inspection; the storage area is a well-ventilated warehouse or shed, and open-air stacking is prohibited, the environmental temperature of the storage area is not less than 5℃, the capillary tube network (1), the water outlet header (2), the water inlet header (3) and the header (4) are stored in the shelf or flat ground in a box, the stacking height is not more than 1.5m, the matched pipe material is horizontally stacked, the storage area is away from oil, chemicals, heat source and fire source, fire prevention measures are taken, the access channel is free of sharp objects, and the advanced first-out principle is implemented.

3. The energy tube segment pre-production process of claim 1, wherein, In the capillary tube network heat exchanger assembly and fixation step, the capillary tube network (1) is aligned and positioned with the reinforcement cage of the same type, and the capillary tube network (1) is tightly attached to the outer arc surface of the reinforcement cage; the capillary tube network (1) is fixed by using a steel wire mesh strap, and the spacing of the steel wire mesh strap is 4cm; one end of the water inlet header (3) away from the capillary tube network (1) and the water outlet (5) are inserted into the rubber positioner for fixation, and the one end of the water inlet header (3) away from the capillary tube network (1) and the water outlet (5) are provided with sealing plugs; the material of the capillary tube network (1) is subjected to metal passivation treatment, the installation and construction environmental temperature is not less than 5℃, and when the environmental temperature is 5℃ to 10℃, heating measures are needed to make the environmental temperature higher than 10℃.

4. The energy tube segment pre-fabrication production process of claim 1, wherein, In the pipe segment pouring and curing step, the pipe segment mold cleanliness and the steel reinforcement cage protective layer thickness need to be checked before pouring; C50 concrete is used, and the concrete is poured in layers through an attached vibrator, and during pouring, the capillary tube network (1), water outlet header (2), water inlet header (3), and header (4) are completely covered by the concrete and are not loose; immediately after pouring, the outer arc surface of the pipe segment body is scraped and compacted; if the capillary tube network (1), water outlet header (2), water inlet header (3), or header (4) is displaced during pouring, pouring needs to be temporarily suspended, the displacement direction and offset amount are recorded, the steel reinforcement cage and capillary tube network heat exchanger position are corrected, and then pouring is continued after re-fixing.

5. The process for the prefabricated production of energy tubes according to claim 4, characterized in that, The pipe segment curing is carried out by steam curing or water curing; when steam curing, the temperature rise rate is not more than 15℃ per hour, the temperature is raised to 60℃, and then constant temperature curing is carried out, the constant temperature curing environment humidity is not less than 90%, and the temperature drop rate is not more than 20℃ per hour, and the pipe segment body demolding strength is not less than 20MPa; when water curing, the pipe segment body is immersed in water for 7 to 14 days, the water temperature and pipe segment body temperature difference are measured regularly to ensure that the temperature difference is not more than 20℃, and when the temperature difference is greater than 20℃, the water circulation system is started to adjust the water temperature, and the water inlet header (3) far from the capillary tube network (1) end and the water outlet (5) are both installed with protective caps.

6. The energy tube segment pre-fabrication production process of claim 1, wherein, The leakage detection test step includes three times of leakage detection: the first time is water pressure leakage detection test after the capillary tube network heat exchanger and the steel reinforcement cage are fixed, the water pressure leakage detection test sampling rate is not less than 1%, and during the test, water is injected into the water inlet header (3), and whether the capillary tube network (1), water outlet header (2), header (4), and water outlet (5) are leaking is observed; the second time is air tightness test after the pipe segment body is prefabricated; the third time is air tightness test after the pipe segment body arrives at the site; the test pressure of the air tightness test is all 0.8MPa, and during the test, gas is introduced into the water inlet header (3), and the pressure change of the water outlet (5) and header (4) is monitored.

7. The energy tube segment pre-fabrication production process of claim 1, wherein, In the pipe segment assembly step, the pipe segment selection is carried out first, and the design axis, shield tail gap, and push oil cylinder stroke difference are considered comprehensively during selection; The staggered joint assembly method is used, and the pipe segment body is installed from bottom to top block by block; the top block in the pipe segment body is first pushed into two-thirds of the width radially, and then inserted longitudinally; before and after assembly, the shield tail sundries need to be cleaned, and the pipe segment body water stop strip sticking quality is checked, and immediately after assembly, protective caps are installed on the water inlet header (3) far from the capillary tube network (1) end and the water outlet (5), and the push oil cylinder at the pipe segment installation position and the push oil cylinder at the non-pipe segment installation position are prohibited from being retracted at the same time.

8. The energy tube segment pre-fabrication production process of claim 7, wherein, During pipe segment assembly, the bolts are tightened synchronously, and the bolt tightening follows the three times of re-tightening principle: the first time of re-tightening is carried out when the lower ring push stroke is more than half; the second time of re-tightening is carried out after the lower ring pipe segment body assembly is completed; the third time of re-tightening is carried out after the pipe segment body is demolded from the shield tail, and the torque of each bolt tightening meets the design requirements, which ensures that the pipe segment body is assembled stably, and the capillary tube network (1), water outlet header (2), water inlet header (3), or header (4) is not damaged due to assembly stress.

9. The energy tube segment pre-production process of claim 3, wherein, Water inlet manifold (3), water outlet manifold (2) and the outer wall of the pipe body between the concrete layer are provided with water sealing gasket, the outer side of the water sealing gasket is pasted with butyl rubber waterproof section, and the outer side of the butyl rubber waterproof section is provided with a kraft paper protection layer, so as to realize the waterproof sealing between the water inlet manifold (3), the water outlet manifold (2) and the concrete layer, and prevent water from penetrating into the capillary tube network (1) or the manifold (4) and damaging the capillary tube network (1) or the manifold (4) during use of the pipe body.

10. The process for the prefabricated production of energy tubes according to claim 6, characterized in that, If leakage of the capillary tube network heat exchanger is found in the leakage detection test, the repair method is as follows: when the capillary tube network (1) leaks, the leakage section is cut off, the cut is kept flat, a special hot melting welding machine is used to butt joint a new pipe section, and the flatness of the welded joint is checked after cooling; when the joint of the manifold (4) and the water inlet manifold (3) or the water outlet manifold (2) leaks, the joint is disassembled, the butyl rubber sealing gasket is replaced, and the joint is tightened again; when the water outlet (5) leaks, the sealing plug is replaced and the rubber positioner is fixed again; after the repair is completed, a pressure maintaining test is carried out, the pressure maintaining pressure is 0.6 MPa, the pressure maintaining time is not less than 15 minutes, the pressure drop during the pressure maintaining process does not exceed 3%, and a stainless steel clamp is additionally added for reinforcement in the repair area, and the spacing of the stainless steel clamps does not exceed 10 cm.

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