Subway assembly type prefabricated track plate type embedded track construction method

Abstract

The invention relates to the field of rail traffic, in particular to a subway assembly prefabricated rail plate type embedded rail construction method which comprises the following steps: S1, construction preparation and base treatment: technicians investigate a site in advance, confirm the position of a civil defense door, and check and accept the quality of an entering prefabricated rail plate and a prefabricated rail bearing table; it is guaranteed that the appearance of the prefabricated slab is free of cracks and damage, the strength grade of base concrete is C35, expansion joints with the width of 20 mm are arranged every 10 m, and the center lines of the expansion joints are aligned with the center lines of slab joints. Compared with a traditional construction method that construction of prefabricated track plates needs to be conducted firstly, temporary fasteners are laid after construction of the track plates is completed, and then the prefabricated concrete track bearing tables are transported to the site for manual track bearing table construction, the construction method has the advantages that the prefabricated track plates and the prefabricated track bearing tables are assembled in the track plate site firstly, and the prefabricated track plates and the prefabricated track bearing tables are assembled in the track plate site; therefore, the construction period for installing the rail bearing platform in the later period is saved.

Description

Technical Field

[0001] The present invention relates to the field of rail transportation, and in particular to a method for constructing a subway assembled prefabricated track plate type embedded track. Background Art

[0002] Rail transit refers to a type of transportation vehicle or transportation system in which operating vehicles need to travel on specific tracks. Urban rail transit is defined as "a general term for fast, large-capacity public transportation that is usually powered by electricity and adopts a wheel-rail operation mode.

[0003] During the traditional rail transit construction process, the construction period is long, the area occupied is large, and the dust and noise are serious, which has a great impact on urban traffic and residents' lives. The line construction site is in the urban area, and the equipment required for construction is of various types, the excavation volume is large, and the noise is high. Affected by the site and the type of urban rail transit, there is currently a lack of a mature and systematic construction method for the assembled prefabricated panel embedded track construction method, resulting in low efficiency and difficulty in ensuring quality during the construction process.

[0004] Therefore, we have made improvements to this problem and proposed a subway assembled prefabricated track plate embedded track construction method. Summary of the Invention

[0005] The purpose of the present invention is to address the problems in the current traditional rail transit construction process, such as long construction period, large floor space, serious dust and noise, and lack of a mature and systematic construction method, which leads to low efficiency and difficulty in ensuring quality during the construction process.

[0006] In order to achieve the above-mentioned purpose of the invention, the present invention provides a method for constructing a subway assembled prefabricated track plate embedded track to improve the above-mentioned problem.

[0007] The specific application is as follows:

[0008] A method for constructing a subway assembled prefabricated track plate embedded track comprises the following steps:

[0009] S1. Construction Preparation and Substrate Treatment: Technical personnel will conduct a site survey in advance to confirm the location of the civil air defense door and inspect the quality of the prefabricated track slabs and prefabricated rail supports. They will ensure that the prefabricated slabs are free of cracks and damage. The substrate concrete strength grade is C35. A 20mm wide expansion joint will be set every 10m, with the centerline of the expansion joint aligned with the centerline of the slab joint. The expansion joint will be filled with a 20mm thick closed-cell polyethylene plastic foam board, and the top surface will be sealed with a 30mm thick polyurethane sealant. Expansion joints will also be set at the locations where the track bed structure changes, and the upper and lower layers will be aligned.

[0010] S2. Factory assembly of prefabricated track slabs and prefabricated rail supports: Use gantry cranes and flatbed trucks to hoist and transport the prefabricated track slabs to the laying site. Use a tunnel gantry crane for initial track slab laying. During initial laying, the centerline and elevation deviation of the prefabricated slabs must be controlled within ±5mm. Install anti-floating pressure bars, and install and reinforce the track support system, with one set installed every 2.5m.

[0011] S3. CPⅢ control network survey and design: Install the track slab adjustment tooling at the track slab hoisting holes, and use a total station to fine-tune the track slab through the CPⅢ control points. Fine-tune the prefabricated slab in curved sections using the half-sag adjustment principle, first horizontally and then vertically.

[0012] S4. Installation of base formwork and concrete construction;

[0013] S5. Lay self-compacting concrete steel mesh, lay track slabs, fine-tune the track slabs, and fix the track slabs;

[0014] S6, self-compacting concrete pouring;

[0015] S7, rail laying and welding;

[0016] S8, rail grinding and adhesive application;

[0017] S9, laying of pads in the trough;

[0018] S10, installing the track adjustment assembly;

[0019] S11, track fine-tuning;

[0020] S12, track slab protection and end sealing;

[0021] S13, pouring polymer damping material;

[0022] S14. Clean and retest the lines.

[0023] As the preferred technical solution of this application, self-compacting concrete pouring: a 4mm thick polypropylene non-woven geotextile isolation layer is set between the self-compacting concrete layer and the bottom of the track slab. The geotextile is pasted to the bottom of the track slab before the track slab leaves the factory. The strength of the self-compacting concrete is C40 and the thickness is 90mm. The track slab is fully filled with self-compacting concrete. Measures are taken to prevent the track slab from floating during pouring, and it is ensured that there is no leakage during pouring to prevent pollution of the track slab. Exhaust holes are set on the formwork during pouring. The formwork and bracket can only be removed when the strength of the self-compacting concrete reaches 10MPa. Vehicles can only be driven and load-bearing when the strength reaches 70% of the design strength.

[0024] As the preferred technical solution of this application, rail laying: after the construction of the overall roadbed is completed, rails are laid, and temporary locking can be performed as needed to meet the requirements of rail welding and temporary traffic. The iron pads and elastic pads under the rails are installed and arranged with two embedded sleeves between them. The temporary locking fasteners are released and recovered when welding the rails.

[0025] As the preferred technical solution of this application, rail welding: 60kg / m rails are used for track laying, and a mobile contact welding rail car is used to perform rail flash welding on site. The welding method is the same as the fastener-type rail structure. After the rail welding is completed, the rail is rusted and polished.

[0026] As the preferred technical solution of this application, the trough pad is laid: the steel trough pad and the steel trough bottom plate are successively installed at the designed position of the flat base, the elastic pad is pasted in the middle of the steel trough bottom plate, the hole position is aligned with the base hole position, the noise reduction block is pasted and installed on both sides of the rail at the base position, and it cannot invade the concrete rail bearing groove, and welded steel troughs are placed on the left and right sides of the rail on the steel trough bottom plate, the side walls of the welded steel trough are aligned with the side walls of the rail bearing platform, and short gaskets with a thickness of 2mm+4mm+2mm are placed in combination at the designed position, and long gaskets are placed on the side of the steel trough. After the long gasket is bent, the end of the short gasket is clamped.

[0027] As the preferred technical solution of this application, the rails and groove area are cleaned: after removing the spring bars, the rails are lifted at the plate seams, and the rails are polished after being raised with wooden planks. After polishing and rust removal, the rails and track plate surfaces are cleaned in time, and the oil stains on the surface of the rails are cleaned until they are not greasy to the touch. The rust on the lower jaw of the rail head and the rail waist are polished to present a smooth and clean surface. In the entire polishing and transfer process, care is taken to avoid and prevent pollution from floating dust, oil, and water. At the same time, the floating dust and excess garbage in the groove area are cleaned to ensure that there are no water or oil pollutants.

[0028] As the preferred technical solution of this application, the track adjustment assembly is installed: the total station and the track inspection trolley are used to fine-tune the rails. The order of fine-tuning the rails is to adjust the elevation first and then the gauge. The elevation adjustment is achieved by combining height adjustment pads of different thicknesses. The horizontal position of the rails is adjusted by the wedging depth of the wedge blocks. The track adjustment assembly consists of a pair of retaining frames and wedge blocks, which are arranged at equal intervals along the groove area. It is necessary to ensure that a group of track adjustment assemblies are placed at the end position of the track plate, and no track adjustment assemblies are placed in the plate seam steel groove.

[0029] As the preferred technical solution of this application, track fine-tuning: Elevation adjustment: Use a total station in conjunction with a track inspection trolley to collect elevation data of the rail top surface at each height adjustment pad layout position, calculate the configuration thickness of the height adjustment pad under the rail and the rail bottom slope pad at each point according to the design elevation of the rail bottom, mark the deviation thickness value on the rail top, increase and decrease the height adjustment pad according to the marked value, and after the height adjustment pad is laid in place, use the track inspection trolley to collect and compare elevation data again, repeat the above steps until each point meets the design requirement value, horizontal adjustment: first use one rail as the reference rail to adjust the plane position, and adjust the plane position by loosening and tightening the wedge block. After adjusting point by point, tighten the wedge block to complete the reference rail adjustment. After the reference adjustment is completed, adjust the plane position of another rail. After adjusting point by point, tighten the wedge block to complete the fine-tuning of the other rail.

[0030] As the preferred technical solution of this application, track plate protection and end sealing: adhesive re-brushing: the adhesive is re-applied to the bonding interface damaged in the previous process, groove area end face sealing: the groove area end is sealed with foam board and foam glue, rail top surface protection: the rail top surface is protected by tape, and the side of the rail head is pasted not lower than the lower jaw of the rail head on both sides of the rail, and the upper surface of the roadbed is protected by tarpaulin. The protective tape and tarpaulin must not penetrate into the steel plate on the side of the steel trough.

[0031] As the preferred technical solution of this application, casting polymer damping material: polymer damping material is a two-component A and B. All B components are shaken before use to avoid unmixed sediment. When pouring, pour a bucket of B component into the A component bucket and use automatic stirring equipment to fully stir for 2 minutes to fully mix. Pouring starts from one side of the rail. After the polymer material overflows from the bottom of the rail on the other side, pouring is carried out on the other side to prevent air pockets at the bottom of the rail. When pouring, avoid overflowing of the material from the rail groove. After pouring, continue to scrape the surface bubbles of the polymer material to ensure that there are no large and dense bubbles on the surface. The pouring height is controlled between -5mm and 0mm relative to the top surface of the rail groove. After each shift, clean the working surface protection and residual glue, the stirring head of the stirrer needs to be cleaned, waterproof and sun-proof during the curing process, and external force disturbance of the rail is prohibited. After the material is matured, use a torque wrench to check the torque and re-tighten to the design torque value of 250N·m~300N·m.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] In the scheme of this application:

[0034] 1. In order to solve the problems of long construction period, large floor area, serious dust and noise, and lack of a mature and systematic construction method in the existing rail transit construction process, which leads to low efficiency and difficult to ensure quality during the construction process, compared with the traditional construction method, this application requires the construction of prefabricated track plates first, and after the construction of the track plates is completed, temporary fasteners are laid, and then the prefabricated concrete rail supports are transported to the site for manual construction of the rail supports. This method first assembles the prefabricated track plates and prefabricated rail supports in the track plate yard, and transports them together to the construction site for installation, which saves the construction time of the later installation of the rail supports, the required equipment occupies a small area, reduces the noise and dust generated during the construction process, and improves construction efficiency.

[0035] 2. This application saves the cost of temporary fasteners in traditional construction methods and saves construction costs. The track structure is a unit plate type, adopts the design concept of plate and groove separation, and connects the prefabricated plates and prefabricated rail platforms through high-strength bolts to form a continuously supported groove structure. It is assembled on site and continuously optimized to solve the problems of narrow construction space, intensive cross-operations, and limited use of large-scale machinery and equipment, so that the embedded track construction has the characteristics of high mechanization and installation quality, short cycle, easy operation, and good comprehensive benefits.

[0036] 3. This application adopts continuous support and elastic locking to embed the rails into the integral roadbed, improves the wheel-rail contact relationship, effectively controls the vibration noise of the track and vehicle from the source and transmission path, provides a quieter living environment for residents along the urban rail transit line, reduces noise pollution to the surrounding environment, has excellent anti-stray current function, helps to ensure the electrical safety of the rail transit system, reduces equipment failures and safety hazards caused by stray currents, and improves the operational reliability of the rail transit system.

[0037] 4. This application clarifies the construction steps and requirements through the assembled prefabricated panel embedded track construction method, making the construction process more orderly and efficient, reducing uncertainty and rework during the construction process, shortening the construction period, and accelerating the construction progress of the rail transit project. It also makes detailed provisions for each construction link, such as the quality acceptance of prefabricated track panels and prefabricated rail platforms during construction preparation and base treatment, the setting of expansion joints, and the fine-tuning requirements during the track panel laying process, ensuring that the construction quality meets the design requirements and improving the overall performance and service life of the track system.

[0038] 5. Based on the characteristics of the line and environmental impact assessment requirements, this application adopts a new type of assembled prefabricated panel embedded track bed structure in high-vibration reduction areas, and through continuous practice and innovative construction methods, it can adapt to rail transit projects with different geological conditions, line environments and operational requirements, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A flowchart of the process flow for the construction method of the subway assembled prefabricated track slab embedded track provided in this application;

[0040] Figure 2 A block diagram of the in-groove construction principle of the subway assembled prefabricated track slab embedded track construction method provided in this application;

[0041] Figure 3 A schematic diagram of a cross-section of a prefabricated embedded track slab roadbed for the subway assembled prefabricated track slab embedded track construction method provided in this application;

[0042] Figure 4 Schematic diagram of the structure inside the elastic groove of the assembled prefabricated plate segment of the subway assembled prefabricated track plate embedded track construction method provided in this application;

[0043] Figure 5 Schematic diagram of the installation of the prefabricated rail support platform for the subway assembled prefabricated track plate embedded track construction method provided in this application;

[0044] Figure 6 Schematic diagram of the control points for adjusting the flat curve of the prefabricated slab in the construction method of the subway assembled prefabricated track slab embedded track provided in this application;

[0045] Figure 7 A schematic diagram of the positions of temporary locking fasteners for the subway assembled prefabricated track slab embedded track construction method provided in this application;

[0046] Figure 8 Schematic diagram of the grinding parts of the construction method of the subway assembled prefabricated track plate embedded track provided in this application;

[0047] Figure 9 Schematic diagram of the installation of the plate seam steel channel for the construction method of the subway assembled prefabricated track plate embedded track provided in this application;

[0048] Figure 10 Schematic diagram of gasket installation for the subway assembled prefabricated track slab embedded track construction method provided in this application;

[0049] Figure 11 Schematic diagram of rail painting for the construction method of subway assembled prefabricated track slab embedded track provided in this application;

[0050] Figure 12 Schematic diagram of the installation of the rail adjustment component in the slot of the subway prefabricated track plate embedded track construction method provided in this application;

[0051] Figure 13 Schematic diagram of the arrangement of track adjustment components for the subway assembled prefabricated track plate embedded track construction method provided in this application;

[0052] Figure 14 Schematic diagram of rail fine-tuning in the groove for the construction method of subway assembled prefabricated track slab embedded track provided in this application;

[0053] Figure 15 Schematic diagram of the rail and roadbed protection area for the subway assembled prefabricated track plate embedded track construction method provided in this application. DETAILED DESCRIPTION

[0054] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0055] As described in the background art, in the traditional rail transit construction process, the construction period is long, the area occupied is large, the dust and noise are serious, and there is a lack of a mature and systematic construction method, which leads to low efficiency and difficulty in ensuring quality during the construction process.

[0056] In order to solve this technical problem, the present invention provides a subway assembled prefabricated track plate type embedded track construction method, which is applied to the field of rail transportation.

[0057] Specifically, please refer to Figures 1-15 A method for constructing a subway assembled prefabricated track plate embedded track comprises the following steps:

[0058] S1. Construction Preparation and Substrate Treatment: Technical personnel will conduct a site survey in advance to confirm the location of the civil air defense door and inspect the quality of the prefabricated track slabs and prefabricated rail supports. They will ensure that the prefabricated slabs are free of cracks and damage. The substrate concrete strength grade is C35. A 20mm wide expansion joint will be set every 10m, with the centerline of the expansion joint aligned with the centerline of the slab joint. The expansion joint will be filled with a 20mm thick closed-cell polyethylene plastic foam board, and the top surface will be sealed with a 30mm thick polyurethane sealant. Expansion joints will also be set at the locations where the track bed structure changes, and the upper and lower layers will be aligned.

[0059] S2. Factory assembly of prefabricated track slabs and prefabricated rail supports: Use gantry cranes and flatbed trucks to hoist and transport the prefabricated track slabs to the laying site. Use a tunnel gantry crane for initial track slab laying. During initial laying, the centerline and elevation deviation of the prefabricated slabs must be controlled within ±5mm. Install anti-floating pressure bars, and install and reinforce the track support system, with one set installed every 2.5m.

[0060] S3. CPⅢ control network survey and design: Install the track slab adjustment tooling at the track slab hoisting holes, and use a total station to fine-tune the track slab through the CPⅢ control points. Fine-tune the prefabricated slab in curved sections using the half-sag adjustment principle, first horizontally and then vertically.

[0061] S4. Installation of base formwork and concrete construction;

[0062] S5. Lay self-compacting concrete steel mesh, lay track slabs, fine-tune the track slabs, and fix the track slabs;

[0063] S6, self-compacting concrete pouring;

[0064] S7, rail laying and welding;

[0065] S8, rail grinding and adhesive application;

[0066] S9, laying of pads in the trough;

[0067] S10, installing the track adjustment assembly;

[0068] S11, track fine-tuning;

[0069] S12, track slab protection and end sealing;

[0070] S13, pouring polymer damping material;

[0071] S14. Clean and retest the lines.

[0072] Compared with the traditional construction method, this application requires the construction of prefabricated track plates first, laying temporary fasteners after the construction of the track plates is completed, and then the prefabricated concrete track supports are transported to the site for manual construction of the track supports. This method first assembles the prefabricated track plates and prefabricated track supports in the track plate yard, and then transports them together to the construction site for installation, which saves the time for the later installation of the track supports, shortens the construction period, requires less equipment space, reduces the noise and dust generated during the construction process, and improves construction efficiency.

[0073] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0074] Example 1, please refer to Figures 1-15 A method for constructing a subway assembled prefabricated track plate embedded track comprises the following steps:

[0075] S1. Construction Preparation and Substrate Treatment: Technical personnel will conduct a site survey in advance to confirm the location of the civil air defense door and inspect the quality of the prefabricated track slabs and prefabricated rail supports. They will ensure that the prefabricated slabs are free of cracks and damage. The substrate concrete strength grade is C35. A 20mm wide expansion joint will be set every 10m, with the centerline of the expansion joint aligned with the centerline of the slab joint. The expansion joint will be filled with a 20mm thick closed-cell polyethylene plastic foam board, and the top surface will be sealed with a 30mm thick polyurethane sealant. Expansion joints will also be set at the locations where the track bed structure changes, and the upper and lower layers will be aligned.

[0076] S2. Factory assembly of prefabricated track slabs and prefabricated rail supports: Use gantry cranes and flatbed trucks to hoist and transport the prefabricated track slabs to the laying site. Use a tunnel gantry crane for initial track slab laying. During initial laying, the centerline and elevation deviation of the prefabricated slabs must be controlled within ±5mm. Install anti-floating pressure bars, and install and reinforce the track support system, with one set installed every 2.5m.

[0077] The geometric size and stability of the track can be controlled by adjusting the various screw components of the track support system.

[0078] S3. CPⅢ control network survey and design: Install the track slab adjustment tooling at the track slab hoisting holes, and use a total station to fine-tune the track slab through the CPⅢ control points. Fine-tune the prefabricated slab in curved sections using the half-sag adjustment principle, first horizontally and then vertically.

[0079] Horizontal adjustment: first use the cross mark points (control point 1 and control point 2) on the center line of the precast slab as the reference control points of the precast slab, and use the fine-tuning tooling on the four corners of the precast slab to adjust the cross mark points of each precast slab to the center line of the line. Elevation adjustment: adjust the control points on the four corners of the precast slab (control point 3 to control point 6) to adjust the elevation of the precast slab to the correct position. The spacing between the center lines of the track plates is 200+10mm.

[0080] S4. Installation of base formwork and concrete construction;

[0081] S5. Lay self-compacting concrete steel mesh, lay track slabs, fine-tune the track slabs, and fix the track slabs;

[0082] S6, self-compacting concrete pouring;

[0083] S7, rail laying and welding;

[0084] S8, rail grinding and adhesive application;

[0085] S9, laying of pads in the trough;

[0086] S10, installing the track adjustment assembly;

[0087] S11, track fine-tuning;

[0088] S12, track slab protection and end sealing;

[0089] S13, pouring polymer damping material;

[0090] S14. Clean and retest the lines.

[0091] Self-compacting concrete pouring: A 4mm thick polypropylene non-woven geotextile isolation layer is set between the self-compacting concrete layer and the bottom of the track slab. The geotextile is pasted to the bottom of the track slab before the track slab leaves the factory. The strength of the self-compacting concrete is C40 and the thickness is 90mm. The self-compacting concrete of the track slab is fully filled without obvious bubbles. Measures are taken to prevent the track slab from floating during pouring, and it is ensured that there is no leakage during pouring to prevent contamination of the track slab. Exhaust holes are set on the formwork during pouring. The formwork and support can only be removed when the strength of the self-compacting concrete reaches 10MPa. Vehicles can only be driven and load-bearing can only be carried when the strength reaches 70% of the design strength.

[0092] Rail laying: After the overall trackbed construction is completed, rails are laid. Temporary locking can be performed as needed to meet the requirements of rail welding and temporary traffic. The iron pads and elastic pads under the rails are installed and arranged with two embedded sleeves between them. The temporary locking fasteners are released and recovered during rail welding.

[0093] Rail welding: 60kg / m rails are used for track laying, and mobile contact welding rail vehicles are used for on-site rail flash welding. The welding method is the same as that of the fastener-type rail structure. After the rail welding is completed, the rails are rust-removed and polished.

[0094] Rail welding requirements:

[0095] 1. Check the rail end face (vertical and horizontal direction), end bend, and rail body straightness. The end face slope of the rail should not exceed 0.8mm;

[0096] 2. Rust removal and grinding of the rail end face and both sides of the rail waist within 500mm from the end face;

[0097] 3. After the rail surface and jaws are polished, the welding machine should be aligned. The weld should be aligned with the center of the rail welding machine jaws. Use a knife edge ruler to check that the left and right and height misalignment of the two rails should not exceed 0.5mm.

[0098] 4. After confirming that the rail is aligned, start the hydraulic system to clamp the rail, then activate the data acquisition system and enter the welding process. After going through each flash stage, perform top forging and complete the nodule removal operation. At the same time, perform a straightness test on the weld to prevent low joints.

[0099] 5. Use a grinding wheel machine to grind the welds and the top, side and bottom of the rail head;

[0100] 6. After the weld position is polished, use medium frequency normalizing equipment for normalizing. After the welding head cools to room temperature, use a contour rail grinder for fine polishing. After polishing, use a 1-meter ruler to measure: the straightness of the top surface of the rail welding head is 0mm~0.3mm, the straightness of the inner working surface of the rail head is not more than 0.3mm, and the protrusion of the rail bottom does not exceed 1mm; the grinding depth is not more than 0.5mm.

[0101] Example 2 further optimizes the subway assembled prefabricated track plate embedded track construction method provided in Example 1. Specifically, Figures 1-15 As shown, the trough pad is laid: the steel trough pad and the steel trough bottom plate are successively installed at the designed position of the flat pedestal, and the elastic pad is pasted in the middle of the steel trough bottom plate, and the hole position is aligned with the pedestal hole position, and the noise reduction block is pasted and installed on both sides of the rail at the pedestal position, and it cannot invade the concrete rail bearing trough. On the steel trough bottom plate, welded steel troughs are placed on the left and right sides of the rail, and the side walls of the welded steel trough are aligned with the side walls of the rail bearing platform. Short gaskets with a thickness of 2mm+4mm+2mm are placed in combination at the designed position, and long gaskets (150mm×10mm×2mm) are placed on the side of the steel trough. After the long gasket is bent, the end of the short gasket is clamped.

[0102] According to the position of the welding steel channel, place the pressure plate, heavy spring washers and flat washers, press the steel channel to both sides (make sure the gasket is in close contact with the steel channel), screw the bolts into the base sleeve and tighten them.

[0103] Adhesive application: The adhesive is a two-component adhesive, A and B (red after mixing). Component B needs to be stirred evenly before use. Manually stir and mix quickly for more than 3 minutes. Use a short-bristled thumb roller brush (replaceable brush head) to apply the adhesive evenly without any missing or sagging. The application should be thin rather than thick. The rail bottom does not need to be applied by brushing. The lower jaw of the rail head, the upper surface of the noise reduction block and the upper part of the inner wall of the plate seam steel groove need to be applied by brushing.

[0104] Pad installation: Before installation, ensure that the track surface is free of moisture, dust, and debris, and that the pad is free of oil and damage.

[0105] Installation of elastic pads: The elastic pads are laid continuously in the center with no overlap or gaps at the ends. The pads are tightly attached to the bottom of the groove during bonding to ensure that the pad surface is flat.

[0106] Installation of height adjustment pads: Place height adjustment pads with a combined thickness of 13mm in the groove in advance. The actual thickness is adjusted according to the subsequent fine-tuning measurement results. The spacing between the height adjustment pads is 1m. The spacing at the plate ends can be increased or widened. No height adjustment pads are installed at the plate seam steel groove.

[0107] Installation of rail bottom slope pad: Lay the rail bottom slope pad above the height adjustment pad. When laying, be sure to place the thinner side of the pad toward the inside of the track plate. No height adjustment pad is installed at the steel groove of the plate seam.

[0108] Cleaning of rails and groove areas: After removing the spring bars, lift the rails at the plate seams and use wooden blocks to raise them before grinding. Clean the rails and track plate surfaces in time after grinding and rust removal. Clean the oil stains on the rail surface until it is not greasy to the touch. Remove the rust on the lower jaw of the rail head and the rail waist. After grinding, pay attention to avoid and prevent pollution from floating dust, oil, and water during the entire grinding and transfer process. At the same time, clean the floating dust and excess garbage in the groove area to ensure that there are no water or oil pollutants.

[0109] Install the track adjustment assembly: Use a total station and a track inspection trolley to fine-tune the rails. The order of rail fine-tuning is elevation adjustment first and then gauge adjustment. Use a combination of height adjustment pads of different thicknesses to achieve elevation adjustment, and use the wedging depth of the wedge block to achieve horizontal position adjustment of the rails. The track adjustment assembly consists of a pair of retainers and wedge blocks, which are arranged at equal intervals (550mm±10mm) along the groove area. Make sure to place a set of track adjustment assemblies at the end of the track plate, and do not place track adjustment assemblies in the plate seam steel groove.

[0110] Track fine-tuning: Elevation adjustment: Use a total station in conjunction with a track inspection trolley to collect elevation data on the top surface of the rail for each height adjustment pad layout position, calculate the configuration thickness of the height adjustment pad and the rail bottom slope pad at each point according to the design elevation of the rail bottom, mark the deviation thickness value (height adjustment amount) on the rail top, increase or decrease the height adjustment pad according to the marked value, and after the height adjustment pad is laid in place, use the track inspection trolley to collect and compare the elevation data again, repeat the above steps until each point meets the design requirement value, horizontal adjustment: first use one rail as the reference rail to adjust the plane position, and adjust the plane position by loosening and tightening the wedge block. After adjusting point by point, tighten the wedge block to complete the reference rail adjustment. After the reference adjustment is completed, adjust the plane position of another rail. After adjusting point by point, tighten the wedge block to complete the fine-tuning of the other rail.

[0111] Track plate protection and end sealing: Adhesive re-brushing: Re-apply adhesive to the bonding interface damaged in the previous process, groove end face sealing: Use foam board and foam glue to seal the end of the groove area, rail top surface protection: The top surface of the rail is protected by tape, and the side of the rail head is pasted not lower than the lower jaw of the rail head on both sides of the rail, and the upper surface of the roadbed (on both sides of the rail groove) is protected by tarpaulin. The protective tape and tarpaulin must not penetrate into the steel plate on the side of the steel groove.

[0112] Example 3 further optimizes the subway assembled prefabricated track plate embedded track construction method provided in Example 1 or 2. Specifically, Figures 1-15As shown, pour the polymer damping material: the polymer damping material consists of two components, A and B. Shake all B components before use to avoid unmixed sediment. When pouring, pour one bucket of B component into the A component bucket (pour out B component completely) and stir thoroughly for 2 minutes using automatic stirring equipment to mix thoroughly. Start pouring from one side of the rail and wait until the polymer material overflows from the bottom of the rail on the other side before pouring on the other side to prevent air pockets at the bottom of the rail. Avoid overflowing the rail groove during pouring. After pouring, continuously scrape the surface of the polymer material to ensure that there are no large and dense bubbles on the surface. The pouring height relative to the top surface of the rail groove should be controlled between -5mm and 0mm. After each shift, clean the work surface protection and residual glue. The stirring head of the stirrer should be cleaned. During the curing process (within 72 hours after pouring), waterproof and sun-proof measures should be taken. External force disturbance of the rail is prohibited. After curing, use a torque wrench to check the torque and re-tighten to the designed torque value of 250N·m to 300N·m.

[0113] The preparation method of the polymer damping material comprises the following steps:

[0114] S1. Screening: Obtain a polyurethane prepolymer sample, determine its chemical structure by infrared spectroscopy, determine its molecular weight distribution by gel permeation chromatography, and select a polyurethane prepolymer with a molecular weight distribution within 1000-5000;

[0115] S2. Pretreatment: Place the selected polyurethane prepolymer in a vacuum drying oven and dry it at 60-80°C for 2-4 hours to remove trace moisture contained therein and avoid bubble defects in subsequent reactions;

[0116] S3. Preparation of Component A: Add the polyurethane prepolymer to a reactor equipped with a stirring device, start stirring at a speed of 50-150 rpm, and stir for 10-30 minutes to uniformly disperse the polyurethane prepolymer. Then add the plasticizer and continue stirring for 15-30 minutes to allow the plasticizer to fully mix with the polymer to improve the flexibility and processing properties of the material. Then add the filler calcium carbonate. The filler must be dried in advance. After adding, increase the stirring speed to 100-200 rpm and stir for 30-60 minutes to ensure that the filler is evenly dispersed in the polymer system to form a stable Component A raw material system.

[0117] Filler drying: Place the calcium carbonate filler in an oven and dry it at 105-120℃ for 2-4 hours to remove the moisture. The dried filler should be immediately placed in a sealed container to prevent it from absorbing moisture again.

[0118] Filler screening: Use a 200-300 mesh sieve to screen the dried calcium carbonate filler to remove large particles of impurities and ensure uniform filler particle size;

[0119] S4. Preparation of Component B: Add the isocyanate curing agent to a clean container and heat it to melt. The heating temperature should be controlled at 40-80°C. After it is completely melted, add the organotin catalyst and stir evenly for 5-15 minutes to evenly disperse the catalyst in the curing agent to form the raw material of Component B.

[0120] Curing agent selection: Choose an isocyanate curing agent and test the purity and isocyanate content of the curing agent;

[0121] S5. Quality testing: The prepared components A and B are tested for quality respectively. For component A, its viscosity, density, and solid content are tested. The viscosity is tested using a rotational viscometer, and the density is tested using a densitometer. The solid content is tested by drying the sample to a constant weight and calculating the solid content. For component B, its active hydrogen content and viscosity index are tested. The active hydrogen content is tested using a chemical analysis method, and the viscosity is also tested using a rotational viscometer.

[0122] S6. Packaging and storage: Components A and B that have passed the inspection shall be packaged separately. Component A can be packaged in plastic barrels. Component B, due to its high activity, needs to be packaged in well-sealed containers to prevent it from reacting with moisture in the air. Packaged components A and B should be stored in a dry, cool, well-ventilated warehouse, avoiding direct sunlight and high temperature environment. The storage temperature should be controlled between 5-30℃. During storage, inventory materials should be inspected regularly to ensure their stable quality.

[0123] Track plate position tolerance chart

[0124]

[0125] Table of allowable deviations for fine adjustment of positioning of precast slabs

[0126] Serial number name Allowable deviation (mm) 1 elevation ±3 2 midline 5 3 Relative difference in the bottom of the rail groove at the joints of adjacent track plates 3 4 Relative plane position of the bottom of the rail groove at the joint of adjacent track plates 3

[0127] Track fine-tuning and laying accuracy requirements chart

[0128]

[0129] Construction material list

[0130]

[0131] The process principle of the present invention is as follows:

[0132] The prefabricated embedded track adopts prefabricated track plates and prefabricated rail supports. The prefabricated track plates and prefabricated rail supports are prefabricated in the factory. The finished prefabricated track plates and prefabricated rail supports are assembled into one piece in the factory in advance, transported to the track-laying base by car and stored. The concrete pouring construction of the prefabricated plate base is completed by concrete transport vehicles before the prefabricated plate is laid. The gantry crane and the truck crane are used to lift the assembled prefabricated track plates and rail supports onto the track flat car in the track-laying base. The track car is transported to the construction site. A track laying machine is used on the working surface to lift and lay precast panels. The track CPⅢ control network and supporting measurement systems and tooling equipment are used to adjust the geometric positions of the precast panels. After fine-tuning, the self-compacting concrete edge sealing formwork and anti-floating device are installed, and self-compacting concrete pouring, line rails, laying elastic pads and height adjustment pad installation are carried out. A mobile flash contact welding machine is used for seamless line construction. After the rail welding is completed, a track inspection vehicle is used for fine-tuning. Finally, the polymer damping material is poured. After passing the quality inspection, the line is opened and the embedded track construction is completed.

[0133] The construction of assembled prefabricated plate embedded track can realize accurate and rapid adjustment of embedded track by completing the advance assembly of prefabricated plates and prefabricated rail supports in the factory, laying and fine-tuning of prefabricated plates, self-compacting concrete, rail laying and welding, rail fine-tuning, and polymer material construction in the groove. It solves the problems of small on-site installation and construction space of rail supports, multiple cross-constructions, and high safety risks. This method can be directly promoted and applied in the construction of prefabricated plate embedded track in subways of major cities, which can greatly improve construction quality and efficiency, and facilitate the coordination and management of the owner unit during construction. Without affecting the realization of the design goals and construction period requirements of the prefabricated plate embedded track structure, it greatly reduces the confusion in construction control management and the waste of resources, and produces significant social and economic benefits.

[0134] Obviously, the embodiments described above are only some embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are given in the accompanying drawings, but they do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned specific embodiments, or to make equivalent replacements for some of the technical features therein. Any equivalent structure made using the contents of the present invention specification and drawings, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present invention.

Claims

1. A method for constructing a subway assembled prefabricated track plate embedded track, characterized in that: The following steps are involved: S1. Construction Preparation and Substrate Treatment: Technical personnel will conduct a site survey in advance to confirm the location of the civil air defense door and inspect the quality of the prefabricated track slabs and prefabricated rail supports. They will ensure that the prefabricated slabs are free of cracks and damage. The substrate concrete strength grade is C35. A 20mm wide expansion joint will be set every 10m, with the centerline of the expansion joint aligned with the centerline of the slab joint. The expansion joint will be filled with a 20mm thick closed-cell polyethylene plastic foam board, and the top surface will be sealed with a 30mm thick polyurethane sealant. Expansion joints will also be set at the locations where the track bed structure changes, and the upper and lower layers will be aligned. S2. Factory assembly of prefabricated track slabs and prefabricated rail supports: Use gantry cranes and flatbed trucks to hoist and transport the prefabricated track slabs to the laying site. Use a tunnel gantry crane for initial track slab laying. During initial laying, the centerline and elevation deviation of the prefabricated slabs must be controlled within ±5mm. Install anti-floating pressure bars, and install and reinforce the track support system, with one set installed every 2.5m. S3. CPⅢ control network survey and design: Install the track slab adjustment tooling at the track slab hoisting holes, and use a total station to fine-tune the track slab through the CPⅢ control points. Fine-tune the prefabricated slab in curved sections using the half-sag adjustment principle, first horizontally and then vertically. S4. Installation of base formwork and concrete construction; S5. Lay self-compacting concrete steel mesh, lay track slabs, fine-tune the track slabs, and fix the track slabs; S6, self-compacting concrete pouring; S7, rail laying and welding; S8, rail grinding and adhesive application; S9, laying of pads in the trough; S10, installing the track adjustment assembly; S11, track fine-tuning; S12, track slab protection and end sealing; S13, pouring polymer damping material; S14. Clean and retest the lines.

2. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 1, characterized in that: Pouring of self-compacting concrete: A 4mm thick polypropylene non-woven geotextile isolation layer is set between the self-compacting concrete layer and the bottom of the track slab. The geotextile is pasted to the bottom of the track slab before the track slab leaves the factory. The strength of the self-compacting concrete is C40 and the thickness is 90mm. The track slab is fully filled with self-compacting concrete. Measures are taken to prevent the track slab from floating during pouring, and it is ensured that there is no leakage during pouring to prevent contamination of the track slab. Exhaust holes are set on the formwork during pouring. The formwork and support can only be removed when the strength of the self-compacting concrete reaches 10MPa. Vehicles can only be driven and load-bearing can only be carried when the strength reaches 70% of the design strength.

3. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 2, characterized in that: Rail laying: After the overall trackbed construction is completed, rails are laid. Temporary locking can be performed as needed to meet the requirements of rail welding and temporary traffic. The iron pads and elastic pads under the rails are installed and arranged with two embedded sleeves between them. The temporary locking fasteners are released and recovered during rail welding.

4. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 3, characterized in that: Rail welding: 60kg / m rails are used for track laying, and mobile contact welding rail vehicles are used for on-site rail flash welding. The welding method is the same as that of the fastener-type rail structure. After the rail welding is completed, the rails are rust-removed and polished.

5. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 4, characterized in that: Laying of pads in the trough: The steel trough pad and the steel trough bottom plate are successively installed at the designed position of the flat pedestal. The elastic pad is pasted in the middle of the steel trough bottom plate, and the hole position is aligned with the pedestal hole position. The noise reduction block is pasted and installed on both sides of the rail at the pedestal position. It cannot invade the concrete rail bearing trough. On the steel trough bottom plate, welded steel troughs are placed on the left and right sides of the rails. The side walls of the welded steel trough are aligned with the side walls of the rail bearing platform. Short gaskets with a thickness of 2mm+4mm+2mm are placed in combination at the designed position, and long gaskets are placed on the side of the steel trough. After the long gaskets are bent, the ends of the short gaskets are clamped.

6. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 5, characterized in that: Cleaning of rails and groove areas: After removing the spring bars, lift the rails at the plate seams and use wooden blocks to raise them before grinding. Clean the rails and track plate surfaces in time after grinding and rust removal. Clean the oil stains on the rail surface until it is not greasy to the touch. Remove the rust on the lower jaw of the rail head and the rail waist. After grinding, pay attention to avoid and prevent pollution from floating dust, oil, and water during the entire grinding and transfer process. At the same time, clean the floating dust and excess garbage in the groove area to ensure that there are no water or oil pollutants.

7. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 6, characterized in that: Install the track adjustment assembly: Use a total station and a track inspection trolley to fine-tune the rails. The order of rail fine-tuning is elevation adjustment first and then gauge adjustment. Use a combination of height adjustment pads of different thicknesses to achieve elevation adjustment, and use the wedging depth of the wedge block to achieve horizontal position adjustment of the rails. The track adjustment assembly consists of a pair of retainers and wedge blocks, which are arranged at equal intervals along the groove area. Make sure to place a set of track adjustment assemblies at the end of the track plate, and do not place track adjustment assemblies in the plate seam steel groove.

8. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 7, characterized in that: Track fine-tuning: Elevation adjustment: Use a total station in conjunction with a track inspection trolley to collect elevation data on the top surface of the rail for each height adjustment pad layout position, calculate the configuration thickness of the height adjustment pad and the rail bottom slope pad at each point according to the design elevation of the rail bottom, mark the deviation thickness value on the rail top, increase or decrease the height adjustment pad according to the marked value, and after the height adjustment pad is laid in place, use the track inspection trolley to collect and compare the elevation data again, repeat the above steps until each point meets the design requirement value, horizontal adjustment: first use one rail as the reference rail to adjust the plane position, and adjust the plane position by loosening and tightening the wedge block. After adjusting point by point, tighten the wedge block to complete the reference rail adjustment. After the reference adjustment is completed, adjust the plane position of another rail. After adjusting point by point, tighten the wedge block to complete the fine-tuning of the other rail.

9. The method for constructing a subway assembled prefabricated track plate embedded track according to claim 8, characterized in that: Track plate protection and end sealing: Adhesive re-brushing: Re-apply adhesive to the bonding interface damaged in the previous process; Groove end face sealing: Use foam board and foam glue to seal the end of the groove area; Rail top surface protection: The top surface of the rail is protected by tape, and the side of the rail head is pasted not lower than the lower jaw of the rail head on both sides of the rail; The upper surface of the roadbed is protected by tarpaulin, and the protective tape and tarpaulin must not penetrate into the steel plate on the side of the steel groove.

10. A subway assembled prefabricated track plate embedded track construction method according to claim 9, characterized in that: Pouring polymer damping material: The polymer damping material is a two-component A and B. All B components should be shaken before use to avoid unmixed sediment. When pouring, pour a bucket of B component into the A component bucket and stir it thoroughly for 2 minutes with automatic stirring equipment to mix it thoroughly. Start pouring from one side of the rail and wait until the polymer material overflows from the bottom of the rail on the other side before pouring on the other side to prevent air pockets at the bottom of the rail. Avoid overflowing the material from the rail groove during pouring. After pouring, continue to scrape the surface of the polymer material to prevent bubbles from forming on the surface to ensure that there are no large and dense bubbles on the surface. The pouring height should be controlled between -5mm and 0mm relative to the top surface of the rail groove. After each shift, clean the work surface protection and residual glue. The stirring head of the stirrer needs to be cleaned. Waterproof and sun-proof the material during the curing process. External force disturbance of the rail is prohibited. After the material is cured, use a torque wrench to check the torque and re-tighten it to the designed torque value of 250N·m~300N·m.

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