A reusable inflatable rubber wet-seam mold and method of construction

Abstract

The application discloses a reusable inflatable rubber wet joint mold and a construction method, the mold comprises a bottom mold, a side mold and a fixed tie; the bottom mold is a flexible capsule structure formed by the peripheral sealing and compounding of an upper mold and a lower mold, an air bag cavity is formed in the inside and a gas charging and discharging valve is arranged; the side mold is a three-section rubber-steel plate composite structure, comprising a first side plate with an inclined transition, a second side plate with a vertical straight plate and a third side plate with an end chamfer, and is integrally connected with the bottom mold through vulcanization; the fixed tie is arranged in pairs at both ends of the side mold and is used for binding and fastening on the steel rail to provide lateral pressure resistance. The mold is in a flexible contraction state when not inflated, can be easily put into a narrow gap of 30-40 mm at the bottom of the floating plate, is inflated to expand and adhere to the side wall of the wet joint to form reliable sealing, is contracted after being deflated and can be quickly taken out, and reuse is realized. The mold can be repeatedly used, construction cost is significantly reduced, and construction efficiency and safety are improved.

Description

Technical Field

[0001] This invention relates to the field of construction technology for floating slab track beds in rail transit, specifically to a reusable inflatable rubber wet joint mold and construction method, mainly used for casting and forming wet joints between adjacent floating slabs in the construction of steel spring floating slab tracks. Background Technology

[0002] In traditional steel spring floating slab track construction, to ensure track smoothness and structural stability, adjacent floating slabs are typically mechanically connected using shear hinges, i.e., force transmission is achieved through hinged connections between short slabs. With the continuous development of steel spring floating slab technology, the engineering community has proposed a new floating slab connection scheme: using a "wet joint" method to cast multiple floating short slabs into a single integral structure, replacing the traditional shear hinge connection. This wet joint method significantly improves the overall integrity, vibration reduction effect, and connection reliability of the floating slab track, reducing the risk of defects caused by shear hinge wear and loosening during long-term operation. Therefore, it is widely used in newly constructed subway lines.

[0003] However, the construction of wet joints in floating slabs faces a key challenge: the narrow gap of only 30-40mm between the bottom of the floating slab and the foundation makes conventional wet joint formwork erection and removal difficult. Currently, the mainstream solution used in engineering projects is a one-time concave steel formwork process: an integral concave steel formwork is fixed to the longitudinal reinforcement of the floating slab by welding or bolting vertical steel bars, ensuring the upper surface of the steel formwork is flush with the lower surface of the floating slab; after pouring, the steel formwork is permanently bonded to the wet joint concrete and does not need to be removed. To prevent grout leakage from the sides during concrete pouring, the formwork length must be greater than the width of the wet joint (i.e., the slab width). Therefore, after pouring, the excess formwork must be removed on-site by hot welding.

[0004] While this one-time steel formwork process solves the problem of formwork support in confined spaces, it has significant limitations: (1) The consumption of template materials is large and the construction cost is high. Steel formwork is for single use and cannot be reused after casting, resulting in a large waste of steel.

[0005] (2) Hot work on site increases safety hazards. The removal of formwork requires open flame cutting, which poses a significant fire safety risk in the enclosed underground tunnel space.

[0006] (3) The construction process is complex and inefficient. The welding / bolting of the formwork and the melting and cutting after pouring are complicated procedures, which affect the construction progress and are not conducive to streamlined and standardized operations.

[0007] Therefore, developing a reusable wet joint formwork device that can be quickly installed, reliably sealed, and easily removed after pouring without hot work in the narrow bottom space of a floating slab is a key problem that urgently needs to be solved in current engineering practice. Summary of the Invention

[0008] To overcome the aforementioned problems, the inventors conducted in-depth research and designed a reusable inflatable rubber wet joint mold and construction method, belonging to the technical field of floating slab track bed construction for rail transit. The mold includes a bottom mold, side molds, and fixing straps. The bottom mold is a flexible bladder structure formed by the sealing of the upper and lower molds, with an internal air bladder cavity equipped with an inflation / deflation valve. The upper mold has greater rigidity than the lower mold, with a flat top surface, while the lower mold can adapt to irregular contours of the base. The side mold is a three-section rubber-steel plate composite structure, including a first side plate with a sloping transition, a second side plate with a vertical straight plate, and a third side plate with chamfered ends, integrally connected to the bottom mold through vulcanization. Fixing straps are paired at both ends of the side molds for securing them to the rails and providing lateral pressure resistance. When deflated, the mold is in a flexible, contracted state, easily fitting into the narrow 30-40mm gap at the bottom of the floating slab. After inflation, it expands to fit against the sidewall of the wet joint, forming a reliable seal. After deflation, it contracts and can be quickly removed, enabling reuse. This method replaces the traditional disposable steel mold, eliminates hot work operations, shortens the installation and dismantling time of a single wet joint, reduces the number of operators required, and allows the mold to be reused multiple times, significantly reducing construction costs and improving construction efficiency and safety, thus completing the present invention.

[0009] Specifically, the purpose of this invention is to provide a reusable inflatable rubber wet joint mold. Includes bottom mold 1, side mold 2, and fixing components 3; The bottom mold 1 is a flexible capsule structure with a sealed cavity inside, and its upper surface is a forming surface used to form the bottom surface of the wet joint concrete 4. The bottom mold 1 is provided with an air inlet / outlet 5. By filling the sealed cavity with a medium, the bottom mold 1 expands and fits against the structural surface around the wet joint. By discharging the medium, the bottom mold 1 shrinks so that it can be demolded and removed. The side mold 2 is connected to the side of the bottom mold 1 and is used to form the side profile of the wet joint concrete 4. The fixing member 3 is disposed on the side mold 2 and is used to fix the side mold 2 to an external fixing support point to constrain the displacement of the side mold during the concrete pouring process.

[0010] The bottom mold 1 includes an upper mold 11 and a lower mold 12. The upper mold 11 and the lower mold 12 are sealed together at their periphery, forming the sealed cavity 13 between them. The inflation / deflation port 5 is fixedly disposed at the end of the bottom mold 1 and communicates with the sealed cavity 13; Preferably, the rigidity of the upper mold 11 is greater than that of the lower mold 12, the top surface of the upper mold 11 is a flat forming surface, and the lower mold 12 is used to fit the irregular contour surface of the bottom of the wet joint.

[0011] Among them, on the upper mold 11, there are upwardly protruding flexible sealing lips integrally formed on both sides of the side mold 2, which are not provided. The flexible sealing lips are used to form an active seal by first closely adhering to the bottom of the floating plate after inflation.

[0012] A flexible space limiting structure is provided inside the sealed cavity. The upper and lower ends of the flexible space limiting structure are connected to the inner wall surface of the upper mold 11 and the inner wall surface of the lower mold 12, respectively, to constrain the expansion shape of the bottom mold 1 after inflation.

[0013] The side mold 2 includes a first side plate 21, a second side plate 22, and a third side plate 23 connected in sequence. The first side plate 21 is an oblique transition plate, the second side plate 22 is a vertical straight plate, and the third side plate 23 is an end chamfer plate; The fixing component 3 includes a fixing strap, which is arranged in pairs at both ends of the side mold. One end of the fixing strap is fixedly connected to the side mold, and the other end is used to bind and tighten it after bypassing the external fixing support point.

[0014] The medium is a gas or a liquid; the mold is made of an oil-resistant and wear-resistant rubber material.

[0015] The present invention also provides a construction method for wet joints of steel spring floating slabs using the mold described above, comprising the following steps: S1: Place the mold, which is in an uninflated and contracted state, into the wet joint position from the bottom of the floating plate, and adjust the position of the mold to align it with the wet joint; S2: The medium is injected into the sealed cavity 13 of the bottom mold 1 through the air inlet / outlet 5, causing the bottom mold 1 to expand. The upper surface of the bottom mold 1 is attached to the lower surface of the floating plate, the lower surface is attached to the surface of the track bed base, and the side mold is attached to the contour of the wet joint side wall to form a sealed casting space. S3: Fix the fixing component to the external fixing point to constrain the side mold 2; S4: Pour concrete into the pouring space; S5: After the concrete reaches the predetermined strength, the medium in the sealed cavity is discharged through the air inlet / outlet 5, causing the bottom mold 1 to shrink. S6: Remove the shrunken mold from the bottom of the floating plate.

[0016] Prior to step S1, a step of spraying a release agent onto the mold surface is also included; Preferably, in step S2, the inflation pressure is 0.02-0.04 MPa; Preferably, in step S5, demolding is performed when the concrete strength reaches 75% of the design strength or 35 MPa.

[0017] In step S3, the fixing component is a fixing cable tie. The fixing cable tie is wrapped around the rail and tied tightly to the rail body. The rail is used as a fixing fulcrum to apply an inward pulling constraint force to the side mold.

[0018] The beneficial effects of this invention include: (1) The reusable inflatable rubber wet joint mold provided by this invention can be reused, significantly reducing construction costs. Using an inflatable flexible rubber mold, each set of molds can be reused more than 50 times, completely changing the traditional disposable steel mold's "one-time casting, one-time scrapping" material consumption model. Taking the construction of 50 wet joints as an example, the traditional steel mold process requires approximately 2.5 tons of steel, while this invention only requires one set of molds to complete all construction, reducing material costs by more than 95%. At the same time, the mold is made of oil-resistant and wear-resistant neoprene rubber or EPDM rubber, has a long service life, and extremely low cost per use, demonstrating excellent economic efficiency.

[0019] (2) The reusable inflatable rubber wet joint mold and construction method provided by this invention are convenient and efficient to install and demold, significantly improving construction efficiency. The mold is a flexible, shrinkable body in its uninflated state, easily fitting into the narrow 30-40mm gap at the bottom of the floating slab without the need for complex hoisting equipment. After placement, inflation completes the expansion and sealing; demolding only requires deflation and shrinkage for extraction, eliminating the need for cumbersome welding and cutting processes. Field tests show that the traditional disposable steel mold process takes 25 minutes to install and dismantle a single wet joint mold (15 minutes for welding and fixing + 10 minutes for melting and cutting), while the mold installation and dismantling time for a single wet joint mold of this invention is only 10 minutes (including placement, inflation, cable ties, deflation, and extraction), increasing construction efficiency by approximately 60%. Simultaneously, the personnel requirement is reduced from 5 people in the traditional process to 3 people, reducing labor costs by 40%.

[0020] (3) The reusable inflatable rubber wet joint mold and construction method provided by this invention completely eliminates hot work operations, significantly improving construction safety. Traditional processes require the use of an oxygen-acetylene flame to melt and cut off excess steel mold portions exceeding the width of the wet joint after concrete pouring. Hot work operations in enclosed spaces such as underground tunnels pose significant fire hazards and harmful gas emissions. This invention completely eliminates the mold cutting process, requiring no open flame operations, fundamentally eliminating the fire safety risks associated with hot work operations in enclosed underground spaces, improving the working environment, and enhancing construction safety.

[0021] (4) The reusable inflatable rubber wet joint mold and construction method provided by this invention have reliable sealing and stable molding quality. The flatness of the concrete bottom surface is ensured by the flat molding surface of the upper mold (the deviation is controlled within ±2mm); the high flexibility of the lower mold can adapt to the irregular contour of the base and the central water ditch, achieving flexible close fit; the three-section side mold forms the wet joint with a gradual thickness contour, vertical sidewall and end chamfer in one step, eliminating the need for manual trimming later; the fixing straps tied to the rail provide lateral pressure restraint for the side mold, effectively preventing the side mold from moving outward, deforming and warping during concrete pouring. As verified by the examples, the wet joint constructed by the present invention has no leakage phenomenon, the molding quality is excellent, and the pass rate reaches 100%, while the leakage rate of the simple inflatable mold without fixing straps reaches 24%, and some parts need to be reworked.

[0022] (5) The reusable inflatable rubber wet joint mold provided by this invention has strong adaptability and a wide range of applications. The mold can be adapted to wet joints of different widths, and the inflation pressure is adjustable within the range of 0.02-0.04MPa. Different gap sizes can be adapted by adjusting the inflation volume. At the same time, the mold can be used with air or with liquids such as water. The liquid filling scheme utilizes the incompressibility of liquids to make the support more stable, and the circulating cooling liquid can reduce the impact of concrete hydration heat on the thermal aging of the mold and extend the mold's life. This solution is not only suitable for the construction of wet joints of steel spring floating slabs, but also for other similar narrow space concrete pouring scenarios such as post-pouring strips between slabs and construction joints, and has good prospects for promotion and application. Attached Figure Description

[0023] Figure 1 This diagram illustrates a three-dimensional structure of the reusable inflatable rubber wet joint mold provided by the present invention. Figure 2 This diagram illustrates the installation of the reusable inflatable rubber wet joint mold provided by the present invention. Figure 3 This diagram illustrates the bottom mold structure of the reusable inflatable rubber wet joint mold provided by the present invention. Figure 4This diagram illustrates the side mold structure of the reusable inflatable rubber wet joint mold provided by the present invention. Figure 5 This invention provides a top view of the plate joint after the reusable inflatable rubber wet joint mold has been fixed. Figure 6 This invention provides a side view of the plate joint after the reusable inflatable rubber wet joint mold has been fixed. Figure 7 A top view of a floating plate after concrete pouring has been poured into the joint, using the reusable inflatable rubber wet joint mold provided by the present invention. Figure 8 The diagram shows a top view of the floating plate using the reusable inflatable rubber wet joint mold provided by the present invention, after the finishing process is completed and the mold is removed.

[0024] Figure Labels 1-Bottom mold, 11-Upper mold, 12-Lower mold, 13-Sealed cavity, 2-Side mold, 21-First side plate, 22-Second side plate, 23-Third side plate, 3-Fixing component, 4-Wet joint concrete, 5-Air filling / venting port. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present invention will become clearer and more apparent.

[0026] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0027] This invention provides a reusable inflatable rubber wet joint mold, such as... Figure 1 As shown, it includes a bottom mold 1, a side mold 2, and a fixing component 3.

[0028] The bottom mold 1 is a flexible capsule structure with a sealed cavity inside, and its upper surface is a forming surface used to form the bottom surface of the wet joint concrete 4. The bottom mold 1 includes an upper mold 11 and a lower mold 12. The upper mold 11 and the lower mold 12 are sealed together around their peripheries, forming the sealed cavity 13 between them. The bottom mold 1 is provided with an air inlet / outlet 5. By filling the sealed cavity with a medium, the bottom mold 1 expands and fits against the structural surface around the wet joint. By discharging the medium, the bottom mold 1 shrinks to allow for demolding and removal.

[0029] The air inlet / outlet 5 is fixedly installed at the end of the bottom mold 1 and communicates with the sealed cavity 13; an air inlet / outlet valve is provided at the air inlet / outlet 5. The air inlet / outlet valve is used to pressurize the sealed cavity 13 and release pressure after construction, so as to realize the expansion and shaping of the mold and the shrinkage and demolding.

[0030] Preferably, the upper mold 11 has a higher rigidity than the lower mold 12, and is made of a thickened rigid rubber layer. The top surface of the upper mold 11 is a flat forming surface that directly contacts the bottom of the wet joint concrete to ensure the flatness and alignment of the concrete bottom surface. The lower mold 12 uses a thin, highly flexible rubber layer that can adapt to the irregular contours of the base and central drainage ditch, achieving flexible and tight fit and preventing grout leakage. The upper mold 11 has a higher rigidity than the lower mold 12. This layered structure design allows the bottom mold to form a flat forming surface on the top surface and adapt to the irregular contours of the base surface after inflation.

[0031] Preferably, on the upper mold 11, there are upwardly protruding flexible sealing lips integrally formed on both sides of the side mold 2 not provided. The flexible sealing lips are used to form an active seal by first closely adhering to the bottom of the floating plate after inflation, which further enhances the reliability of preventing grout leakage.

[0032] As a further optimization, a flexible spatial limiting structure is provided inside the sealed cavity, preferably a densely packed filament or a spaced fabric with a predetermined thickness. The upper and lower ends of the flexible spatial limiting structure are respectively connected to the inner wall surface of the upper mold 11 and the inner wall surface of the lower mold 12, preferably by vulcanization bonding. This structure can ensure that the upper surface of the entire bottom mold 1 forms a flat supporting plane after inflation, accurately control the expansion shape, prevent the mold from twisting in the length direction, and play a role similar to a reinforcing rib.

[0033] In a preferred embodiment, the side mold 2 is connected to the side of the bottom mold 1 and is used to form the side profile of the wet joint concrete 4. The side mold 2 includes a first side plate 21, a second side plate 22 and a third side plate 23 connected in sequence; The first side plate 21 is an oblique transition plate, the second side plate 22 is a vertical straight plate, and the third side plate 23 is an end chamfer plate; In this application, the side mold 2 is a rubber-steel plate composite structure with an internal steel plate skeleton to ensure rigidity. The steel plate skeleton is located at the first side plate 21, the second side plate 22, and the third side plate 23. All three side plates / skeletons are covered with wear-resistant rubber. The three side plates are integrally connected to the upper rubber side of the bottom mold 1 by vulcanization. The side plates can be flexibly bent without splicing gaps and have a self-sealing effect, that is, the flexibility of the rubber material is used to achieve a certain degree of bending.

[0034] The first side plate 21 is an inclined transition section plate, which realizes a smooth and gradual transition between the bottom mold 1 and the vertical side mold, forming the gradually varying thickness profile of the wet joint. The second side plate 22 is a vertical straight plate, which forms the vertical sidewall forming surface of the wet joint and restrains the lateral deformation of the concrete. The third side plate 23 is an end chamfering plate, which is used to form the end chamfer of the wet joint in one go, eliminating the need for manual trimming later.

[0035] The side mold 2 can be centered and positioned with the bottom mold 1. After inflation, it fits tightly against the outline of the floating plates on both sides, blocking the lateral leakage of concrete grout.

[0036] In a preferred embodiment, the fixing member 3 is disposed on the side mold 2 and is used to fix the side mold 2 to an external fixing point to constrain the displacement of the side mold during the concrete pouring process.

[0037] The fixing component 3 includes fixing straps, which are arranged in pairs at both ends of the side formwork. One end of each fixing strap is fixedly connected to the side formwork, and the other end is used to secure it after bypassing the external fixing support. Preferably, a steel rail is used as the external fixing support. In this application, the function of the fixing straps 3 is to apply an inward pulling constraint force to the side formwork 2, restraining the outward displacement, deformation, and warping of the side plate caused by the lateral pressure of the poured concrete, ensuring the stability of the wet joint width, gradient line, and chamfer dimensions, and further enhancing the side sealing and grout leakage prevention effect.

[0038] In this application, the bottom mold, side mold, and fixing components can all be made of oil-resistant and wear-resistant rubber materials, preferably neoprene rubber or ethylene propylene diene monomer (EPDM) rubber. These materials possess excellent oil resistance, wear resistance, aging resistance, and weather resistance, enabling them to adapt to concrete construction environments and ensuring a lifespan that can be reused multiple times.

[0039] As an alternative, this mold can also be filled with a liquid such as water to replace gas. Liquids are incompressible, which makes the support more stable; at the same time, liquids have a high specific heat capacity, which helps to reduce the mold temperature during the peak of concrete hydration heat through circulating coolant, reducing the thermal aging effect of high temperatures on the rubber and further extending the mold's service life. The present invention also provides a method for constructing wet joints of steel spring floating slabs using the mold described above, the method comprising the following steps: S1: Place the uninflated, deflated mold into the wet joint position from the bottom of the floating plate. That is, insert the uninflated rubber mold from the bottom of one side of the floating plate and allow it to emerge from the bottom of the other side, completing the mold placement below the wet joint. Then adjust the mold's position so that its center point coincides with the intersection of the wet joint's center line and the line's center line, ensuring the mold is centered. S2: Inject the medium into the sealed cavity 13 of the bottom mold 1 through the air inlet 5. Observe the expansion state of the mold during the inflation process. When the mold is pressed against the side wall of the wet joint and reaches the set air pressure (0.02-0.04MPa), close the air inlet valve. At this time, the bottom mold 1 expands. The upper surface of the bottom mold 1 is pressed against the lower surface of the floating plate and the lower surface is pressed against the surface of the track bed base. The side mold is pressed against the contour of the side wall of the wet joint to form a sealed casting space. The side mold 2 is pressed against the two side walls of the wet joint to form a side seal. S3: After the side formwork 2 is in place, pull the fixing straps 3 at the ends of the side formwork 2 outward, wrap them around the rail, and secure them tightly to the rail body. The fixing straps 3 provide a stable inward binding force for the side formwork 2, preventing the side formwork from shifting or leaking grout due to the lateral pressure of the concrete during the pouring process; S4: Pour concrete into the pouring space; pour high-strength mortar or concrete at the wet joint until it is flush with the upper surface of the floating slab, thus completing the wet joint pouring operation.

[0040] S5: After the concrete reaches the predetermined strength, that is, 75% of the design strength or 35MPa, the medium in the sealed cavity is discharged through the air inlet / outlet 5, causing the bottom mold 1 to shrink. S6: Remove the shrunken mold from the bottom of the floating plate, clean it, and it can be used for the next section of wet joint construction, thus achieving reuse.

[0041] Preferably, before step S1, a step of spraying a release agent onto the mold surface is included to reduce the demolding resistance after concrete pouring, facilitating subsequent mold recycling. The water-based release agent is environmentally friendly and pollution-free, and will not corrode rubber materials. Example

[0042] In a construction project for a steel spring floating slab track bed on an underground urban rail transit line, the gap between the bottom of the floating slab and the base is 35mm. A total of 50 wet joints need to be constructed, each with a width (along the track direction) of 600mm and a length equal to the width of the floating slab (approximately 2.8m). The reusable inflatable rubber wet joint mold of this invention is used for construction.

[0043] Construction process: The construction team consists of 3 people: 1 person is responsible for the handling, positioning and inflation of the mold, 1 person is responsible for concrete pouring and vibration, and 1 person serves as the on-site construction manager.

[0044] During the mold pretreatment stage, workers evenly spray water-based release agent onto the mold surface, taking approximately 2 minutes per mold. During mold placement, one worker inserts the uninflated flexible rubber mold from one side of the floating slab and out the other, adjusting and aligning it, taking approximately 3 minutes per mold. During the inflation and sealing stage, air is inflated into the air chamber 13 to 0.03 MPa through the inflation / deflation port 5, causing the mold to expand and adhere to the wet joint sidewall to form a seal, taking approximately 1 minute per mold. During the securing stage, the securing cable ties 3 are wrapped around the steel rail and secured tightly, taking approximately 2 minutes per mold. During the concrete pouring and curing stage, high-strength mortar is poured and vibrated to ensure compaction, curing to 75% of the design strength (approximately 3 days). During the demolding stage, the inflation / deflation port 5 is opened to release air, and the mold shrinks and is pulled out from the bottom, taking approximately 2 minutes per mold.

[0045] Construction effect: Field measurements showed that, using the inflatable rubber mold of this invention, the total time for mold installation and demolding of a single wet joint (excluding concrete pouring and curing) was approximately 10 minutes. After all 50 wet joints were completed, the mold showed no significant wear and could be reused for the next construction section. The mold is expected to be reusable more than 50 times.

[0046] Comparative Example A certain project uses the traditional one-time concave steel mold process for wet joint construction. The construction conditions are basically the same as those in Example 1, namely, the bottom gap of the floating plate is 35mm and there are 50 wet joints.

[0047] Construction process: The construction team consists of 5 people: 2 people are responsible for the handling and welding of steel formwork, 1 person is responsible for operating welding equipment, 1 person is responsible for concrete pouring, and 1 person is responsible for on-site management.

[0048] The construction process for each wet joint is as follows: The integral concave steel formwork is hoisted to the wet joint location (due to the large weight of the steel formwork, two people are required to carry it). It is then fixed to the longitudinal reinforcement of the floating slab by welding vertical reinforcing bars. Welding takes approximately 15 minutes per joint. After pouring concrete and curing it to the design strength, an oxy-acetylene flame is used for open-flame cutting to melt and remove the excess steel formwork portion exceeding the width of the wet joint. This cutting operation takes approximately 10 minutes per joint and requires the use of fire-fighting equipment and dedicated personnel for monitoring.

[0049] Construction effect: The total time for mold installation and removal for a single wet joint (excluding concrete pouring and curing) is approximately 25 minutes, which is about 15 minutes longer than in Embodiment 1 of this invention, resulting in an efficiency reduction of about 60%. The 50 wet joints consumed approximately 2.5 tons of steel, significantly increasing material costs. Furthermore, the open-flame cutting operations within the underground tunnel generated a large amount of smoke and harmful gases, polluting the working environment and posing a fire hazard.

[0050] The present invention has been described above with reference to preferred embodiments; however, these embodiments are merely exemplary and illustrative. Various substitutions and modifications can be made to the present invention based on these embodiments, all of which fall within the scope of protection of the present invention.

Claims

1. A reusable inflatable rubber wet joint mold, characterized in that, It includes a bottom mold (1), side molds (2) and fixing components (3); The bottom mold (1) is a flexible capsule structure with a closed cavity inside, and its upper surface is a forming surface used to form the bottom surface of the wet joint concrete (4). The bottom mold (1) is provided with an air inlet / outlet (5). By filling the sealed cavity with a medium, the bottom mold (1) expands and fits against the structural surface around the wet joint. By discharging the medium, the bottom mold (1) shrinks so that it can be demolded and removed. The side mold (2) is connected to the side of the bottom mold (1) and is used to form the side profile of the wet joint concrete (4). The fixing component (3) is disposed on the side mold (2) and is used to fix the side mold (2) to an external fixing point to constrain the displacement of the side mold during the concrete pouring process.

2. The reusable inflatable rubber wet joint mold according to claim 1, characterized in that, The bottom mold (1) includes an upper mold (11) and a lower mold (12). The upper mold (11) and the lower mold (12) are sealed together around their peripheries, forming the sealed cavity (13) between them. The inflation / deflation port (5) is fixedly disposed at the end of the bottom mold (1) and communicates with the sealed cavity (13); Preferably, the upper mold (11) has a higher rigidity than the lower mold (12), the top surface of the upper mold (11) is a flat forming surface, and the lower mold (12) is used to fit the irregular contour surface at the bottom of the wet joint.

3. The reusable inflatable rubber wet joint mold according to claim 2, characterized in that, On the upper mold (11), there are upwardly protruding flexible sealing lips integrally formed on both sides of the side mold (2) where no side mold is provided. The flexible sealing lips are used to form an active seal by first closely adhering to the bottom of the floating plate after inflation.

4. The reusable inflatable rubber wet joint mold according to claim 2, characterized in that, A flexible space limiting structure is provided inside the sealed cavity. The upper and lower ends of the flexible space limiting structure are connected to the inner wall of the upper mold (11) and the inner wall of the lower mold (12) respectively, in order to constrain the expansion shape of the bottom mold (1) after inflation.

5. The reusable inflatable rubber wet joint mold according to claim 1, characterized in that, The side mold (2) includes a first side plate (21), a second side plate (22) and a third side plate (23) connected in sequence. The first side plate (21) is an oblique transition plate, the second side plate (22) is a vertical straight plate, and the third side plate (23) is an end chamfer plate.

6. The reusable inflatable rubber wet joint mold according to claim 1, characterized in that, The fixing component (3) includes a fixing strap, which is arranged in pairs at both ends of the side mold. One end of the fixing strap is fixedly connected to the side mold, and the other end is used to be tied and tightened after bypassing the external fixing support.

7. The reusable inflatable rubber wet joint mold according to any one of claims 1 to 6, characterized in that, The medium is gas or liquid; the mold is made of oil-resistant and wear-resistant rubber material.

8. A method for constructing wet joints of steel spring floating slabs using the mold described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1: Place the mold, which is in an uninflated and contracted state, into the wet joint from the bottom of the floating plate, and adjust the position of the mold to align it with the wet joint; S2: The medium is injected into the sealed cavity (13) of the bottom mold (1) through the air inlet (5) to expand the bottom mold (1). The upper surface of the bottom mold (1) is attached to the lower surface of the floating plate, the lower surface is attached to the surface of the track bed base, and the side mold is attached to the contour of the wet joint side wall to form a sealed casting space. S3: Fix the fixing component to the external fixing point to constrain the side mold (2); S4: Pour concrete into the pouring space; S5: After the concrete reaches the predetermined strength, the medium in the sealed cavity is discharged through the air inlet (5), causing the bottom mold (1) to shrink. S6: Remove the shrunken mold from the bottom of the floating plate.

9. The construction method for wet joints of steel spring floating slabs according to claim 8, characterized in that, The step of spraying a release agent onto the mold surface is included before step S1; Preferably, in step S2, the inflation pressure is 0.02-0.04 MPa; Preferably, in step S5, demolding is performed when the concrete strength reaches 75% of the design strength or 35 MPa.

10. The construction method for wet joints of steel spring floating slabs according to claim 8, characterized in that, In step S3, the fixing component is a fixing cable tie. The fixing cable tie is wrapped around the rail and tied tightly to the rail body. The rail is used as a fixing fulcrum to apply an inward pulling constraint force to the side mold.

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