A subway assembled prefabricated track plate type embedded track construction method

Abstract

The application relates to the field of rail transit, in particular to a subway assembled prefabricated track plate embedded track construction method, which comprises the following steps: S1, construction preparation and basement treatment: a technician investigates the site in advance, confirms the position of the civil air defense door, and inspects the quality of the prefabricated track plate and the prefabricated track support platform, ensures that the prefabricated track plate is free of cracks and damage, the strength grade of the basement concrete is C35, a 20mm-wide expansion joint is arranged every 10m, and the center line of the expansion joint is aligned with the center line of the plate joint. Compared with the traditional construction method, the prefabricated track plate construction needs to be carried out first, the temporary fastener is laid after the track plate construction is completed, and the prefabricated concrete track support platform is transported to the site for manual track support platform construction. According to the method, the prefabricated track plate and the prefabricated track support platform are assembled in the track plate field first, and are transported to the construction site for installation, so that the construction period of the track support platform in the later stage is saved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rail transit, in particular to a subway prefabricated track slab embedded track construction method. BACKGROUND

[0002] Rail transit refers to a type of transportation tool or system in which vehicles operate on a specific track. Urban rail transit is defined as a rapid mass transit system that typically uses electric power and operates on wheel-rail tracks.

[0003] In the traditional rail transit construction process, the construction period is long, the land occupation area is large, the dust and noise are serious, and it has a great impact on urban traffic and residents' life. The line construction site is in the urban area, and the construction requires a variety of equipment, large excavation volume, and loud noise. Due to the influence of site and urban rail transit type, there is currently a lack of a mature and systematic construction method for the prefabricated track slab embedded track construction method, resulting in low efficiency and quality problems during construction.

[0004] Therefore, we improve it and propose a subway prefabricated track slab embedded track construction method. SUMMARY

[0005] The present application aims to solve the problems of long construction period, large land occupation area, serious dust and noise, and lack of a mature and systematic construction method in the traditional rail transit construction process, resulting in low efficiency and quality problems during construction.

[0006] To achieve the above-mentioned application purpose, the present application provides a subway prefabricated track slab embedded track construction method to improve the above-mentioned problems.

[0007] The present application is as follows:

[0008] A subway prefabricated track slab embedded track construction method, comprising the following steps:

[0009] S1, construction preparation and base treatment: the technical personnel investigate the site in advance, confirm the position of the civil air defense door, and check the quality of the incoming prefabricated track slab and prefabricated track slab, ensure that the appearance of the prefabricated slab is free of cracks and damage, the base concrete strength grade is C35, every 10m sets a 20mm wide expansion joint, the expansion joint center line is aligned with the slab joint center line, the expansion joint is filled with 20mm thick closed-cell polyethylene plastic foam board, the top surface is sealed with 30mm thick polyurethane sealant, and expansion joints are also set at the track bed structure changes. The upper and lower expansion joints are aligned;

[0010] S2, prefabricated track slab and prefabricated rail support platform factory assembly: using gantry crane and flat car to hoist and transport prefabricated track slab to laying point, using tunnel gantry crane to initially lay track slab, the center line and elevation deviation of prefabricated flat plate is controlled within ± 5mm during initial laying, anti-floating pressure bar is installed, track support system is installed and reinforced, and one set is set every 2.5m;

[0011] S3, CPⅢ control network surveying and setting: track slab hoisting hole installation and plate adjusting tool, through CPⅢ control point, using total station to adjust track slab, semi-vector adjustment principle is used for prefabricated flat plate fine adjustment in curve section, adjusting in horizontal first and then elevation way;

[0012] S4, base formwork installation and concrete construction;

[0013] S5, laying self-compacting concrete steel mesh, laying track slab, fine adjusting track slab, and fixing track slab;

[0014] S6, self-compacting concrete pouring;

[0015] S7, rail laying and welding;

[0016] S8, rail grinding and adhesive brushing;

[0017] S9, laying groove pad;

[0018] S10, installing and adjusting track assembly;

[0019] S11, track fine adjustment;

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

[0021] S13, pouring high polymer damping material;

[0022] S14, line cleaning and re-measuring.

[0023] As a preferred technical scheme of the present application, self-compacting concrete pouring: 4mm thick polypropylene non-woven geotextile isolation layer is arranged between the self-compacting concrete layer and the track slab bottom, the geotextile is pasted on the track slab bottom before the track slab leaves the factory, the self-compacting concrete strength is C40, the thickness is 90mm, the track slab self-compacting concrete is filled full, measures are taken to prevent the track slab from floating up during pouring, and the pouring is ensured to be without slurry leakage and to prevent the track slab from being contaminated, and exhaust holes are arranged on the formwork during pouring, the formwork and support can be removed only when the self-compacting concrete strength reaches 10MPa, and vehicles and loads can be driven only when the strength reaches 70% of the design strength.

[0024] As the preferred technical solution of the present application, the steel rail laying: after the whole track bed construction is completed, the steel rail laying is carried out, the temporary locking can be carried out as needed, the requirements of welding rail and temporary traffic are met, the iron pad plate and the elastic pad plate under the rail are installed and arranged with two embedded sleeves, the temporary locking fastener is released and recycled when welding the rail.

[0025] As the preferred technical solution of the present application, the steel rail welding: the track laying adopts 60kg / m steel rail, the mobile contact rail welding vehicle is used to carry out the steel rail flash welding construction on site, the welding mode is the same as the fastener track structure, and the steel rail rust removal and polishing are carried out after the steel rail welding is completed.

[0026] As the preferred technical solution of the present application, the groove pad laying: the steel groove pad and the steel groove bottom plate are installed in the designed position of the flat slab bearing platform in sequence, the elastic pad plate is pasted in the middle of the steel groove bottom plate, the hole position is aligned with the bearing platform hole position, the noise reduction block is pasted and installed on both sides of the bearing platform position of the steel rail, cannot intrude into the concrete bearing rail groove, the welding steel groove is placed on the left and right sides of the steel rail on the steel groove bottom plate, the side wall of the welding steel groove is aligned with the side wall of the bearing rail platform, the short pad piece with the thickness of 2mm+4mm+2mm is placed and combined at the designed position, and the long pad piece is placed on the side of the steel groove, and the short pad piece end is clamped by the long pad piece after being bent.

[0027] As the preferred technical solution of the present application, the steel rail and groove area cleaning: after the elastic strip is removed, the steel rail is jacked up at the plate joint, and is polished after being raised by the wooden board, the steel rail and the track plate surface are cleaned in time after polishing and rust removal, the oil stain on the surface of the steel rail is cleaned until the hand touch has no greasy feeling, the rust at the lower jaw of the rail head and the rail waist part is polished to present a clean and smooth surface, and attention is paid to avoiding and preventing dust, oil and water from adhering and polluting during the whole polishing and sequence conversion process, and the groove area dust and excess garbage are cleaned to ensure that there is no water and oil pollution.

[0028] As the preferred technical solution of the present application, the installation and rail adjustment assembly: the total station and the rail inspection trolley are used to finely adjust the steel rail, the fine adjustment sequence of the steel rail is elevation adjustment first and then gauge adjustment, the elevation adjustment is realized by combining the height adjustment pad plates with different thicknesses, and the horizontal position adjustment of the steel rail is realized by the wedge depth of the wedge-shaped block, the rail adjustment assembly is composed of one pair of retaining frames and wedge-shaped blocks, is arranged at equal intervals along the groove area, and a group of rail adjustment assemblies are placed at the end position of the track plate, and the rail adjustment assembly is not placed at the plate joint steel groove.

[0029] As the preferred technical scheme of the present application, the track fine adjustment: height adjustment: use the total station instrument to cooperate with the track detection trolley to collect the height data of the rail top surface of each height adjusting pad plate layout position, calculate the configuration thickness of each point position track height adjusting pad plate and track bottom slope pad plate according to the track bottom design elevation, mark the deviation thickness value on the rail top, and correspondingly increase and decrease the height adjusting pad plate according to the marked value, after the height adjusting pad plate is laid in place, the track detection trolley is used to collect the height data again for comparison, the above steps are repeated until each point position meets the design requirement value, the horizontal adjustment: first, take one rail as the reference rail to adjust the plane position, adjust the plane position through the tight wedge-shaped block, and after adjusting each point in place, the wedge-shaped block is tightly inserted to complete the reference rail adjustment, after the reference adjustment is completed, the plane position adjustment of another rail is carried out, and after adjusting each point in place, the wedge-shaped block is tightly inserted to complete the fine adjustment of the other rail.

[0030] As the preferred technical scheme of the present application, the track plate protection and end sealing: adhesive supplementary brushing: re-paint the adhesive of the damaged bonding interface in the previous process, groove area end sealing: seal the end of the groove area with foam board and foam adhesive, rail top surface protection: paste the protective tape on the rail top surface, paste the protective tape on the rail head side not less than the rail head lower jaw on both sides of the rail, and use the oilcloth to lay and protect the upper surface of the roadbed, and the protective tape and the oilcloth shall not enter the steel groove side plate.

[0031] As the preferred technical scheme of the present application, pouring high polymer damping material: the high polymer damping material is A and B two components, all the B components are shaken before use to avoid the un-mixed sediment, one bucket of B component is poured into the A component bucket during pouring, and the automatic stirring device is used to fully stir for 2 minutes to fully mix and uniform, pouring starts from one side of the rail, and after the high polymer material overflows from the other side of the rail bottom, the other side pouring is carried out to prevent the rail bottom from being aerated, avoid the material overflow from the rail groove during pouring, after pouring is completed, the surface bubbles of the high polymer material are continuously scraped to ensure that the surface is free of large and dense bubbles, the pouring height is controlled between-5mm and 0mm relative to the top surface of the rail groove, the operation is completed every shift, the operation surface is cleaned to prevent the protective tape and the oilcloth from being left, the stirrer stirring head needs to be cleaned, waterproof and sunscreen during the curing process, the rail is prohibited from being disturbed by external force, after the material is cured, the torque wrench is used to review the torque, and the re-tightening reaches the design torque value of 250N.m-300N.m.

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

[0033] In the scheme of the present application:

[0034] 1. In order to solve the problems of long construction period, large occupation area, serious dust and noise, lack of a mature and systematic construction method in the process of rail transit construction in the prior art, which leads to low efficiency and difficult to guarantee the quality in the construction process, the application needs to carry out prefabricated track slab construction compared with the traditional construction method, after the track slab construction is completed, the temporary fastener is laid, and then the prefabricated concrete rail bearing platform is transported to the site for manual rail bearing platform construction. The method firstly assembles the prefabricated track slab and the prefabricated rail bearing platform in the track slab yard, and then transports them to the construction site for installation, which saves the installation period of the later stage, requires small equipment occupation area, reduces the noise and dust generated in the construction process, and improves the construction efficiency.

[0035] 2. The application saves the temporary fastener cost of the traditional construction method, saves the engineering construction cost, the track structure is a unit plate type, adopts a design concept of plate and groove separation, connects the prefabricated plate and the prefabricated rail bearing platform through high-strength bolts, forms a continuous supporting groove-shaped structure, assembles in the yard, continuously optimizes, solves the problems of narrow construction space, dense cross operation, and limited use of large mechanical equipment, so that the embedded track construction has the characteristics of high mechanization degree and installation quality, short period, convenient operation, and good comprehensive benefit.

[0036] 3. The application adopts continuous support and elastic locking to embed the steel rail into the integral track bed, improves the wheel-rail contact relationship, effectively controls the vibration and noise of the track and vehicle from the source and transmission path, provides a more quiet living environment for residents along the urban rail transit, reduces the noise pollution to the surrounding environment, has excellent anti-stray current effect, helps to ensure the electrical safety of the rail transit system, reduces the equipment failure and safety hazards caused by stray current, and improves the operation reliability of the rail transit system.

[0037] 4. The application adopts the assembled prefabricated plate embedded track construction method, clearly defines the construction steps and requirements, makes the construction process more orderly and efficient, reduces the uncertainty and rework phenomenon in the construction process, shortens the construction period, speeds up the construction progress of the rail transit project, and details the construction steps, such as the quality inspection of the prefabricated track slab and the prefabricated rail bearing platform, the setting of expansion joints, and the fine adjustment requirements in the track slab laying process, to ensure that the construction quality meets the design requirements and improve the overall performance and service life of the rail system.

[0038] 5. According to the line characteristics and environmental requirements, the application adopts a new type of assembled prefabricated plate embedded track bed structure in the high-damping section, and continuously practices and innovates the construction method, so that it can adapt to rail transit projects with different geological conditions, line environment and operation requirements, and has wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 Process flow diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0040] Figure 2 Groove construction principle diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0041] Figure 3 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0042] Figure 4 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0043] Figure 5 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0044] Figure 6 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0045] Figure 7 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0046] Figure 8 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0047] Figure 9 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0048] Figure 10 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0049] Figure 11 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0050] Figure 12 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0051] Figure 13 Prefabricated embedded track slab cross section diagram of the subway prefabricated track slab embedded track construction method provided in the present application;

[0052] Figure 14 The steel rail fine adjustment slot diagram provided by the subway prefabricated track slab embedded track construction method of the application is shown in the figure;

[0053] Figure 15 The steel rail and track bed protection area diagram provided by the subway prefabricated track slab embedded track construction method of the application is shown in the figure. DETAILED DESCRIPTION

[0054] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0055] As described in the background, in the traditional rail transit construction process, the construction period is long, the land occupation area 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 in the construction process.

[0056] In order to solve this technical problem, the present application provides a subway prefabricated track slab embedded track construction method, which is applied to the field of rail transit.

[0057] Specifically, please refer to Figures 1-15 A subway prefabricated track slab embedded track construction method, comprising the following steps:

[0058] S1, construction preparation and basement treatment: the technical personnel investigate the site in advance, confirm the position of the civil air defense door, and check the quality of the incoming prefabricated track slab and prefabricated track slab, ensure that the appearance of the prefabricated slab is free of cracks and damage, the strength grade of the basement concrete is C35, a 20mm wide expansion joint is set every 10m, the expansion joint center line is aligned with the slab joint center line, 20mm thick closed-cell polyethylene plastic foam board is filled in the expansion joint, the top surface is sealed with 30mm thick polyurethane sealant, and expansion joints are also set at the track bed structure change, and the upper and lower expansion joints are aligned;

[0059] S2, prefabricated track slab and prefabricated track slab factory assembly: the prefabricated track slab is hoisted and transported to the laying point by using a gantry crane and a flat car, a tunnel gantry crane is used to initially lay the track slab, the center line and elevation deviation of the prefabricated flat plate during initial laying is controlled within ±5mm, an anti-floating pressure bar is installed, the track support system is installed and reinforced, and the interval is 1 set every 2.5m;

[0060] S3, CP III control network surveying and setting: track plate hoisting hole installation and plate adjusting tooling, through CP III control point, using total station to precisely adjust track plate, using half vector adjustment principle to precisely adjust prefabricated flat plate in curve section, adjusting in horizontal first and then in elevation;

[0061] S4, base template installation and concrete construction;

[0062] S5, laying self-compacting concrete steel mesh, laying track plate, precisely adjusting track plate, and fixing track plate;

[0063] S6, self-compacting concrete pouring;

[0064] S7, steel rail laying and welding;

[0065] S8, steel rail grinding and adhesive brushing;

[0066] S9, laying groove pad;

[0067] S10, installing and adjusting track assembly;

[0068] S11, track precise adjustment;

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

[0070] S13, pouring high polymer damping material;

[0071] S14, line cleaning and re-measuring.

[0072] Compared with the traditional construction method, the present application needs to first carry out prefabricated track plate construction, and after the track plate construction is completed, temporary fasteners are laid, and then prefabricated concrete rail supporting platform is transported to the site for manual rail supporting platform construction. The present application first assembles prefabricated track plate and prefabricated rail supporting platform in the track plate field, and then transports them to the construction site for installation, thereby saving the construction period of the later installed rail supporting platform, reducing the construction period, requiring small equipment area, reducing the noise and dust generated during construction, and improving the construction efficiency.

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

[0074] Embodiment 1, please refer to Figures 1-15 A subway assembled prefabricated track plate embedded track construction method, comprising the following steps:

[0075] S1, construction preparation and base treatment: the technical personnel investigate the site in advance, confirm the position of the civil air defense door, and check the quality of the prefabricated track plate and the prefabricated track support platform, ensure that the appearance of the prefabricated plate is free of cracks and damage, the base concrete strength grade is C35, every 10m sets a 20mm wide expansion joint, the expansion joint center line is aligned with the plate joint center line, the expansion joint is filled with 20mm thick closed-cell polyethylene plastic foam board, the top surface is sealed with 30mm thick polyurethane sealant, and expansion joints are also set at the track bed structure change position, and the upper and lower expansion joints are aligned;

[0076] S2, prefabricated plate track plate and prefabricated track support platform factory assembly: the prefabricated track plate is hoisted and transported to the laying point by using a gantry crane and a flat car, a tunnel gantry crane is used to initially lay the track plate, the center line and elevation deviation of the prefabricated flat plate is controlled within ±5mm during initial laying, anti-floating pressure bars are installed, track support systems are installed and reinforced, and the interval is 1 set per 2.5m;

[0077] The geometric size and stability of the track are controlled by adjusting various screw members of the track support system.

[0078] S3, CPⅢ control network surveying and setting: track plate hoisting hole installation and plate adjustment tooling, track plate is adjusted by using a total station through CPⅢ control points, and the semi-vector adjustment principle is adopted for the prefabricated flat plate in the curved section, and the adjustment is in the horizontal first and then the elevation manner;

[0079] Horizontal adjustment: the prefabricated flat plate center line cross mark point (control point 1 and control point 2) is used as the prefabricated flat plate reference control point, the cross mark point of each prefabricated flat plate is located on the line center line by using the prefabricated flat plate four corner fine adjustment tooling, elevation adjustment: the control points (control points 3-6) on the four corners of the prefabricated flat plate are adjusted to adjust the prefabricated flat plate to the right position, and the center line interval between the track plates is 200+10mm.

[0080] S4, base formwork installation and concrete construction;

[0081] S5, laying self-compacting concrete reinforcement mesh, laying track plate, fine adjusting track plate, and fixing track plate;

[0082] S6, self-compacting concrete pouring;

[0083] S7, steel rail laying and welding;

[0084] S8, steel rail grinding and brushing adhesive;

[0085] S9, laying of groove pad;

[0086] S10, installation of rail adjustment assembly;

[0087] S11, track fine adjustment;

[0088] S12, track plate protection and end capping;

[0089] S13, pouring polymer damping material;

[0090] S14, line cleaning and retesting.

[0091] Self-compacting concrete pouring: a 4mm thick polypropylene non-woven geotextile isolation layer is provided between the self-compacting concrete layer and the track plate bottom, the geotextile is pasted on the track plate bottom before the track plate leaves the factory, the self-compacting concrete has a strength of C40 and a thickness of 90mm, the track plate is filled with self-compacting concrete and has no obvious bubbles, measures are taken to prevent the track plate from floating during pouring, and the pouring is ensured to be without slurry leakage and to prevent contamination of the track plate, and an exhaust hole is provided on the formwork during pouring, the formwork and the support can be removed when the self-compacting concrete reaches a strength of 10MPa, and vehicles and loads can be used when the strength reaches 70% of the design strength.

[0092] Rail laying: after the construction of the monolithic track bed is completed, the rail laying is carried out, temporary locking can be carried out as needed to meet the requirements of rail welding and temporary traffic, the iron pads and elastic pads under the rail are installed and arranged with two embedded sleeves in between, and the temporary locking fasteners are removed and recycled during rail welding.

[0093] Rail welding: 60kg / m steel rails are used for track laying, and a mobile contact rail welding vehicle is used for on-site flash welding of the steel rails, the welding method is the same as that of the fastener track structure, and the steel rails are rusted and polished after welding.

[0094] Requirements for rail welding:

[0095] 1. Check the end face of the rail (vertical and horizontal directions), end bending, and rail body flatness, and the end face slope of the rail shall not be greater than 0.8mm;

[0096] 2. Rust and polish the surface of the rail end face and the rail waist within 500mm from the end face;

[0097] 3. After polishing the rail face and the jaw position, align the welding machine, align the center position of the welding seam with the jaw of the rail welding machine, and check that the left and right and high and low misalignment of the two rails shall not exceed 0.5mm with a knife edge ruler;

[0098] 4. After confirming the centering of the rail, start the hydraulic system to clamp the rail, then activate the data acquisition system, enter the welding program, and then perform the top pressing and tumor pushing operations after passing through each flash stage, while detecting the flatness of the welding seam to prevent low joints;

[0099] 5. Use a grinder to polish the welding seam, the top surface, the side surface and the rail bottom of the rail head;

[0100] 6. After the weld seam is ground, use a medium-frequency normalizing equipment for normalizing. After the weld head cools to room temperature, use a profile rail grinding machine for fine grinding. After grinding, use a 1-meter straightedge to measure: the straightness of the top surface of the rail weld head is 0mm to 0.3mm, the straightness of the inner working surface of the rail head is no more than 0.3mm, the protrusion of the rail bottom is no more than 1mm, and the grinding depth is no more than 0.5mm.

[0101] Example 2 further optimizes the subway prefabricated track slab embedded track construction method provided in Example 1. Specifically, as follows: Figures 1-15 As shown, the trough pads are laid as follows: the steel trough pads and the steel trough bottom plate are installed successively at the designed positions on the flat plate foundation. An elastic pad is pasted in the middle of the steel trough bottom plate, with the hole position aligned with the foundation hole position. The noise reduction blocks are pasted and installed on both sides of the steel rail at the foundation position, without encroaching into the concrete rail trough. On the steel trough bottom plate, welded steel troughs are placed on the left and right sides of the steel rail, with the side wall of the welded steel trough aligned with the side wall of the rail foundation. Short shims with a thickness of 2mm+4mm+2mm are placed in combination at the designed position, and long shims (150mm×10mm×2mm) are placed on the side of the steel trough. The long shims are bent and the ends of the short shims are clamped.

[0102] According to the position of the welded steel channel, place the pressure plate, heavy spring washer, and flat washer, and press the steel channel to both sides (ensure that the washer is in close contact with the steel channel). Screw the bolts into the bearing sleeve and tighten them.

[0103] Adhesive application: The adhesive is a two-component mixture of A and B (which turns red after mixing). Component B must be stirred evenly before use. Manually stir quickly for at least 3 minutes. Apply the adhesive evenly with a short-bristled thumb roller brush (with replaceable brush head) to avoid missed spots or drips. The coating should be thin rather than thick. No coating is required on the rail bottom. 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 steel channel in the plate joint need to be coated with adhesive.

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

[0105] Elastic pad installation: The elastic pad is laid continuously in the center with no overlap or gap at the ends. When bonding, the pad is closely attached to the bottom of the groove to ensure that the surface of the pad is flat.

[0106] Installation of height adjustment pads: Place 13mm thick height adjustment pads in the groove beforehand. 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 end of the pads can be increased or decreased. No height adjustment pads are placed at the steel groove of the plate seam.

[0107] Rail base slope pad installation: Lay the rail base slope pad on top of the height adjustment pad. When laying, make sure that the thinner side of the pad faces the inside of the track slab. Do not install height adjustment pads at the steel groove of the slab joint.

[0108] Rail and groove area cleaning: after the removal of the elastic strip, the rail is jacked up at the joint of the plate, and after being raised with a wooden block, the rail is polished. After the rust is removed, the rail and the track plate surface are cleaned in time, the oil on the surface of the rail is cleaned until the hand feels no greasy feeling, the rust at the lower jaw of the rail head is cleaned, the rail waist part is polished to show a clean and smooth surface, and attention is paid to avoiding and preventing dust, oil and water from adhering and polluting during the entire polishing and sequence conversion process. At the same time, the dust and excess garbage in the groove area are cleaned to ensure that there is no water and oil pollution.

[0109] Rail installation and adjustment assembly: full station instrument and rail inspection trolley are used for fine adjustment of the rail. The rail fine adjustment sequence is first elevation adjustment and then gauge adjustment. Different thickness of height adjustment pad combination is used to realize elevation adjustment, and the wedge depth of wedge block is used to realize rail horizontal position adjustment. The rail adjustment assembly is composed of one pair of retaining frames and wedge blocks, which are arranged at equal intervals (550 mm ± 10 mm) along the groove area. It is necessary to ensure that a set of rail adjustment assembly is placed at the end of the track plate. No rail adjustment assembly is placed in the plate joint steel groove.

[0110] Track fine adjustment: elevation adjustment: the full station instrument is used to cooperate with the rail inspection trolley to collect elevation data of the rail top surface at each height adjustment pad layout position. The configuration thickness of the height adjustment pad and the rail bottom slope pad at each point is calculated according to the design elevation of the rail bottom. The deviation thickness value (height adjustment amount) is marked on the rail top. The height adjustment pad is increased and decreased according to the marked value. After the height adjustment pad is laid in place, the rail inspection trolley is used to collect elevation data again for comparison. The above steps are repeated until each point meets the design requirement value. Horizontal adjustment: first, take one rail as the reference rail to adjust the plane position. The plane position is adjusted by the loose wedge block. After adjusting each point in place, the wedge block is tightly inserted to complete the adjustment of the reference rail. After the reference adjustment is completed, the plane position of another rail is adjusted. After adjusting each point in place, the wedge block is tightly inserted to complete the fine adjustment of the other rail.

[0111] Track plate protection and end sealing: adhesive rebrushing: the damaged bonding interface in the previous process is rebrushed with adhesive. Groove area end sealing: the end of the groove area is sealed with foam board and foam adhesive. Rail top surface protection: the rail top surface is protected with adhesive tape, and the rail head side is pasted not less than the rail head lower jaw on both sides of the rail. The upper surface of the track bed (both sides of the rail groove) is protected with an oilcloth. The protective adhesive tape and oilcloth shall not be deep into the steel groove side plate.

[0112] In embodiment 3, the subway assembled prefabricated track plate embedded track construction method provided in embodiment 1 or 2 is further optimized, specifically as follows. Figures 1-15As shown, the pouring of the polymer damping material: the polymer damping material is A, B two components, all B components are shaken before use, avoid the deposition of not mixed, pouring a bucket of B component into the A component barrel (B component pour clean), and use automatic stirring equipment fully stirred 2min fully mixed evenly, pouring from the side of the rail pouring, after the other side of the rail bottom overflow polymer material after the other side pouring, prevent the rail bottom air, pouring to avoid material overflow rail groove, pouring after continuous scraping polymer material surface bubble, ensure that the surface without larger more intensive bubble, pouring height relative to the rail groove top control in-5mm ~ 0mm, each operation after cleaning operation surface protection and left over, mixer stirring head need to be cleaned, curing process (after pouring within 72h) waterproof, sunscreen, prohibit external disturbance rail, material curing after using torque wrench review torque, re tightening to design torque value 250N·m ~ 300N·m.

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

[0114] S1, screening: obtaining polyurethane prepolymer sample, determining its chemical structure by infrared spectrum analysis, determining its molecular weight distribution by gel permeation chromatography, and selecting polyurethane prepolymer with molecular weight distribution of 1000-5000;

[0115] S2, pretreatment: placing the selected polyurethane prepolymer in a vacuum drying oven and drying at 60-80℃ for 2-4 hours to remove the trace amount of water contained therein and avoid air bubble defects in the subsequent reaction;

[0116] S3, preparation of A component: adding polyurethane prepolymer into a reaction kettle with stirring device, starting stirring, controlling stirring speed at 50-150 revolutions per minute, stirring for 10-30 minutes to uniformly disperse the polyurethane prepolymer, then adding plasticizer, continuing stirring for 15-30 minutes to make the plasticizer fully mix with the polymer, so as to improve the flexibility and processing performance of the material, then adding filler calcium carbonate which has been pretreated by drying, increasing the stirring speed to 100-200 revolutions per minute after adding, and stirring for 30-60 minutes to ensure that the filler is uniformly dispersed in the polymer system to form a stable A component raw material system;

[0117] Drying of filler: placing calcium carbonate filler into an oven and drying at 105-120℃ for 2-4 hours to remove the water therein, and immediately placing the dried filler into a sealed container to prevent rehydration;

[0118] Sieve screening of filler: sieving the dried calcium carbonate filler using a 200-300 mesh sieve to remove large particle impurities and ensure uniform particle size of the filler;

[0119] S4, preparation of B component: the isocyanate curing agent is added to a clean container, and needs to be heated and melted first, the heating temperature is controlled at 40-80 DEG C, after complete melting, the organotin catalyst is added, and stirred uniformly, the stirring time is 5-15 minutes, so that the catalyst is uniformly dispersed in the curing agent to form the B component raw material;

[0120] Curing agent selection: select the isocyanate curing agent, and detect the purity and isocyanate group content of the curing agent;

[0121] S5, quality detection: the prepared A and B components are detected in quality respectively, for the A component, the viscosity, density and solid content indexes are detected, the viscosity detection uses a rotational viscometer, the density detection uses a density meter, and the solid content detection is calculated by drying the sample to a constant weight; for the B component, the active hydrogen content and viscosity index are detected, the active hydrogen content detection uses a chemical analysis method, and the viscosity detection also uses a rotational viscometer;

[0122] S6, packaging and storage: the qualified A and B components are packaged respectively, the A component can be packaged in a plastic bucket, the B component needs to be packaged in a container with good sealing property due to high activity, so as to prevent reaction with moisture in the air, and the packaged A and B components should be stored in a dry, cool and ventilated warehouse, and direct sunlight and high temperature environment are avoided, the storage temperature is controlled between 5-30 DEG C, and during storage, the stored materials are regularly inspected to ensure stable quality.

[0123] Track slab position allowable deviation chart

[0124]

[0125] Prefabricated flat plate fine adjustment positioning allowable deviation table

[0126] No. Name Allowable deviation (mm) 1 Elevation ±3 2 Centerline 5 3 Relative gauge difference at the joint between adjacent track panels at the bottom of the track support groove 3 4 Relative flatness at the joint between adjacent track panels at the bottom of the track support groove 3

[0127] Track fine adjustment laying precision requirement chart

[0128]

[0129] Construction material table

[0130]

[0131] The process principle of the process provided by the application is as follows:

[0132] The prefabricated track plate and the prefabricated track support are prefabricated in a factory, the prefabricated track plate and the prefabricated track support are assembled into a whole in the factory, are transported to a track laying base by a vehicle, and are stored, the prefabricated track plate base concrete is constructed before the prefabricated track plate is laid, the prefabricated track plate and the track support are hoisted to a track flat car by a gantry crane and a vehicle crane, the track flat car is transported to a construction site, the prefabricated track plate is hoisted and laid by a track laying machine on an interval construction site, the prefabricated track plate is adjusted in position by a track CP III control network and a matching measurement system and a tooling device, after fine adjustment, a self-compacting concrete sealing edge template and an anti-floating device are installed, self-compacting concrete is poured, a line rail is laid, an elastic pad and a height adjustment pad are installed, a mobile flash butt welding machine is used for seamless line construction, the track is fine-adjusted by a track inspection vehicle after welding, and finally, high polymer damping material is poured, the line is opened after quality inspection, and the embedded track construction is completed.

[0133] The prefabricated track plate embedded track construction realizes accurate and rapid adjustment of the embedded track, solves the problems of narrow construction space, multiple cross construction and high safety risk of the track support on-site installation, can be directly applied to the prefabricated track embedded track construction in various cities, can greatly improve the construction quality and efficiency, is convenient for the coordination and management of the owner unit in construction, greatly reduces the confusion in construction control and management and the waste of resources without affecting the realization of the prefabricated track embedded track structure design target and the construction period requirement, and has remarkable social and economic benefits.

[0134] Obviously, the above-described embodiments are only some embodiments of the present application, but not all the embodiments, the preferred embodiments of the present application are given in the drawings, but do not limit the patent scope of the present application. The present application can be realized in many different forms, and conversely, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or equivalently replace some technical features. Any equivalent structure made by using the content of the present application specification and drawings, directly or indirectly used in other related technical fields, is also within the patent protection scope of the present application.

Claims

1. A method for constructing prefabricated track slabs embedded in subway systems, characterized in that: Includes the following steps: S1. Construction preparation and foundation treatment: Technical personnel will conduct a site survey in advance to confirm the location of the air-raid shelter door and inspect the quality of the precast track slabs and precast track support platforms. They will ensure that the precast slabs are free of cracks and damage. The foundation concrete strength grade is C35. A 20mm wide expansion joint will be set every 10m. The center line of the expansion joint will be aligned with the center line of the slab joint. The expansion joint will be filled with 20mm thick closed-cell polyethylene foam board. The top surface will be sealed with 30mm thick polyurethane sealant. Expansion joints will also be set at the changes in the track bed structure. The expansion and contraction of the upper and lower layers will be aligned. S2. Factory assembly of precast track slabs and precast rail support platforms: The precast track slabs are hoisted and transported to the laying point using gantry cranes and flatbed trucks. The track slabs are initially laid using a tunnel gantry crane. During the initial laying, the center line and elevation deviation of the precast slabs are controlled within ±5mm. Anti-floating pressure bars are installed, and the track support system is installed and reinforced with one set every 2.5m. S3 and CPⅢ control network surveying: Install the track slab hoisting hole adjustment tool, and use a total station to fine-tune the track slab through the CPⅢ control points. For the fine-tuning of the precast slab in curved sections, the principle of half-spur adjustment is adopted, and the horizontal adjustment is adjusted first and then the elevation adjustment. S4. Base formwork installation and concrete construction; S5. Lay self-compacting concrete steel mesh, lay track slabs, fine-tune track slabs, and fix track slabs; S6. Self-compacting concrete pouring; S7, Rail laying and welding; S8. Rail grinding and adhesive application; S9. Laying of padding plates inside the trench; S10. Install the rail adjustment assembly; S11, Track fine-tuning; S12, Track slab protection and end sealing; S13, Casting polymer damping material; S14. Line cleaning and retesting.

2. The construction method for prefabricated track slab embedded track for subway assembly according to claim 1, characterized in that, 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 self-compacting concrete strength is C40 and the thickness is 90mm. The self-compacting concrete of the track slab is fully filled. Measures are taken to prevent the track slab from floating during pouring, and to ensure that the pouring is leak-proof and prevents contamination of the track slab. Vent holes are set on the formwork during pouring. The formwork and support can only be removed when the self-compacting concrete strength reaches 10MPa. Vehicles can only run and bear loads when the strength reaches 70% of the design strength.

3. The construction method for prefabricated track slab embedded track for subway assembly according to claim 2, characterized in that, Rail laying: After the overall track bed construction is completed, the rails are laid. Temporary locking can be carried out as needed to meet the requirements of rail welding and temporary traffic. The iron pads and elastic pads under the rails are installed with two pre-embedded sleeves at intervals. The temporary locking fasteners are released and recycled when welding the rails.

4. The construction method for a prefabricated track slab embedded track for subway assembly according to claim 3, characterized in that, Rail welding: 60kg / m rails are used for track laying. A mobile contact rail welding vehicle is used for on-site flash welding of the rails. The welding method is the same as that for fastener-type rail structures. After the rail welding is completed, the rails are derusted and ground.

5. The construction method for a prefabricated track slab embedded track for subway assembly according to claim 4, characterized in that, In-slot pad installation: The steel channel pad and the steel channel bottom plate are installed successively at the designed position of the flat plate bearing platform. An elastic pad is pasted in the middle of the steel channel bottom plate, with the hole position aligned with the bearing platform hole position. The noise reduction block is pasted and installed on both sides of the steel rail at the bearing platform position, without encroaching into the concrete rail bearing channel. On the steel channel bottom plate, welded steel channels are placed on the left and right sides of the steel rail, with the side wall of the welded steel channel aligned with the side wall of the bearing platform. Short shims with a thickness of 2mm+4mm+2mm are placed in combination at the designed position, and long shims are placed on the side of the steel channel. After bending the long shims, the ends of the short shims are clamped.

6. The construction method for a prefabricated track slab embedded track for subway assembly according to claim 5, characterized in that, Rail and track cleaning: After removing the spring clips, lift the rails at the joints and raise them with wooden blocks before grinding. After grinding and removing rust, clean the rails and track slabs promptly, removing all oil stains from the rail surface until it is no longer greasy to the touch. Ensure that the rust on the rail head and the web area are clean and smooth after grinding. During the entire grinding and transfer process, take care to avoid and prevent dust, oil, and water from adhering and causing contamination. At the same time, clean the track area of ​​dust and excess garbage to ensure that there are no water or oil contaminants.

7. A construction method for prefabricated track slab embedded track for subway assembly according to claim 6, characterized in that, Installation of rail adjustment components: The total station and rail inspection trolley are used to fine-tune the rails. The fine-tuning sequence of the rails is to adjust the elevation first and then the gauge. Elevation adjustment is achieved by using a combination of height adjustment pads of different thicknesses, and the horizontal position of the rails is adjusted by the wedge depth of the wedge blocks. The rail adjustment components consist of a pair of retainers and a pair of wedge blocks, which are arranged at equal intervals along the groove area. It is necessary to ensure that a set of rail adjustment components is placed at the end of the track slab, and no rail adjustment components are placed in the steel groove of the slab joint.

8. A method for constructing a prefabricated track slab embedded track for subway assembly according to claim 7, characterized in that, Track fine-tuning: Elevation adjustment: Using a total station and a track inspection trolley, elevation data is collected on the top surface of the rail at each location where the height adjustment pads are laid. Based on the design elevation of the rail base, the thickness of the height adjustment pads and the rail base slope pads at each point is calculated. The deviation thickness value is marked on the top of the rail. The height adjustment pads are added or removed accordingly according to the marked values. After the height adjustment pads are laid in place, the elevation data is collected and compared again using the track inspection trolley. The above steps are repeated until each point meets the design requirements. Horizontal adjustment: First, one rail is used as the reference rail for horizontal position adjustment. The horizontal position is adjusted by tightening and loosening wedge blocks. After each point is adjusted to the correct position, the wedge blocks are tightened to complete the reference rail adjustment. After the reference adjustment is completed, the horizontal position of the other rail is adjusted. After each point is adjusted to the correct position, the wedge blocks are tightened to complete the fine-tuning of the other rail.

9. A construction method for a prefabricated, modular, embedded track slab for subway construction according to claim 8, characterized in that, Track slab protection and end sealing: Adhesive touch-up: Reapply adhesive to the damaged bonding interface in the previous process; Groove end face sealing: Seal the end of the groove area with foam board and foam adhesive; Rail top surface protection: Protect the top surface of the rail with tape, and attach the tape to the sides of the rail head at a depth not lower than the lower jaw of the rail head on both sides; The upper surface of the track bed is protected with tarpaulin, and the protective tape and tarpaulin must not penetrate into the side steel plate of the groove.

10. A method for constructing a prefabricated, modular, embedded track slab for subway construction according to claim 9, characterized in that, Pouring the polymer damping material: The polymer damping material is a two-component system, A and B. All B components must be shaken well before use to avoid uneven mixing of sediment. During pouring, pour one bucket of B component into the A component bucket and mix thoroughly for 2 minutes using an automatic mixing device. Pouring should begin from one side of the rail. After the polymer material overflows from the bottom of the other rail, pour the other side to prevent air pockets at the bottom of the rail. Avoid the material overflowing from the rail bearing groove during pouring. After pouring, continuously scrape off any air bubbles on the surface of the polymer material to ensure that there are no large or dense air bubbles on the surface. The pouring height should be controlled between -5mm and 0mm relative to the top surface of the rail bearing groove. After each shift, clean the work surface and remove any residual adhesive. The mixing head of the mixer must be cleaned thoroughly. During the curing process, protect the surface from water and sunlight. Do not disturb the rail with external force. After the material has cured, use a torque wrench to check the torque and tighten it to the design torque value of 250 N·m to 300 N·m.

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