Ballastless track winter construction method based on movable thermal insulation shed

Abstract

The invention relates to the technical field of track construction, and discloses a ballastless track winter construction method based on a movable thermal insulation shed, which comprises the following steps: paving a geotechnical cloth isolation layer on the top surface of a ballastless track base, and mounting an elastic cushion layer around a limiting groove; the track panel is assembled on the sub-sleeper platform, the gantry crane hoists the track panel on the bottom-layer steel bars, the steel formworks are installed on the two sides of the bottom-layer steel bars, and the position of the track panel is roughly adjusted and then finely adjusted through the fine adjustment trolley; a heat preservation shed and a warm air gun are adopted for maintenance; after the concrete is initially set, the track panel frame and the formwork are dismantled, and the thermal insulation shed is pulled or pushed by a gantry crane to be maintained to the next cycle; performing heat storage maintenance for 7 days by adopting a plastic film for moisturizing, an electric blanket for heating and a waterproof cotton quilt for heat preservation; and the plastic film and the waterproof cotton quilt continue to be subjected to heat preservation and maintenance for the fourteenth day, it is ensured that the temperature of each procedure of winter construction of the ballastless track bed slab meets the quality control requirement, high-quality ballastless track construction can be completed in winter, and the project progress is greatly accelerated.

Description

Technical Field

[0001] The present invention relates to the technical field of track construction, and particularly relates to a method for winter construction of ballastless tracks based on a mobile heat preservation shed. Background Art

[0002] In the central and northern parts of China and the western plateau regions, the minimum temperature in winter can reach below zero. In areas further north or at higher altitudes, the minimum temperature is easily lower than -10°C. Excessively low temperatures will greatly hinder the setting of cement and easily affect the mechanical properties of the solidified cement. For example, when constructing ballastless tracks, in principle, it is not recommended to construct the ballastless track bed in winter. However, if the construction of ballastless tracks is not carried out throughout the winter, the construction progress will be greatly reduced, resulting in a significant extension of the construction period and inability to deliver on time. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for winter construction of ballastless tracks based on a mobile heat preservation shed to solve the problem that it is difficult to construct ballastless tracks in winter.

[0004] The present invention is achieved through the following technical solutions:

[0005] A method for winter construction of ballastless tracks based on a mobile heat preservation shed divides the construction area into five areas according to the construction sequence: a track panel assembly area L1, a bottom layer steel bar binding area L2 of the track bed slab, a heat preservation track bed pouring area L3, a track bed heat storage and heat preservation maintenance area L4, and a track bed heat preservation maintenance area L5;

[0006] In area L1: ① Stack and store sleepers; ② Divide sleepers on the jig; ③ Assemble the track panel on the jig.

[0007] In area L2: ① Lay the elastic cushion layer and geotextile; ② Bind the steel bars of the limit groove; ③ Bind the bottom layer steel bars.

[0008] In area L3: ① Install the track panel, ② Coarsely adjust the track panel, ③ Finely adjust the track panel, ④ Install the steel bars of the limit groove, ⑤ Bind the top layer steel bar plate, ⑥ Set the resistance, ⑦ Pour the concrete, ⑧ Finish the surface and cure.

[0009] In area L4: ① Cover with plastic film for moisture preservation + use electric blankets to raise the temperature + use waterproof cotton quilts for heat preservation; ② The first day to the seventh day of the maintenance period; ③ Turn off the electric blankets when the temperature is high during the day or exceeds 25°C, and turn on the heating when the temperature in the shed is <5°C; ④ Measure the temperature with a digital display thermometer.

[0010] In area L5: ① Cover with plastic film for moisture preservation + use waterproof cotton quilts for heat preservation; ② The eighth day to the fourteenth day of the maintenance period.

[0011] It includes the following steps:

[0012] S1: Lay a geotextile isolation layer on the top surface of the ballastless track base, install an elastic cushion layer around the limit groove; tie the bottom steel bars and coated insulating steel bars on the geotextile;

[0013] S2: Assemble the rails on the sleeper platform, hoist the rails on the bottom steel bars, install steel templates on both sides of the bottom steel bars, use the fine-tuning trolley to make rough adjustments to the position of the rails and then fine-tune them, collect raw data; install the top steel bars and comprehensive grounding, and measure resistance;

[0014] S3: Concrete is centrally produced in the mixing station, transported by tank trucks, poured by pump trucks, and finished; the data is re-measured by the trolley; the "insulation shed + warm air gun" is used for maintenance; after the initial setting of the concrete, the rail frame and formwork are removed while the gantry crane is used to pull or push the insulation shed for maintenance until the next cycle;

[0015] S4: Adopt "plastic film for moisture retention + electric blanket for heating + waterproof quilt for heat preservation" for 7 days; "plastic film + waterproof quilt" for heat preservation and maintenance until the 14th day;

[0016] S5: Measure the data of the rail support platform and analyze the construction quality based on the test data.

[0017] Preferably, in the first step, the geotextile and elastic cushion layer are cleaned and dried 2 days before pouring the ballast slab, and then laid during the hottest period of the day (ambient temperature ≥ 5°C), and covered to prevent rain and snow. Before installing the elastic cushion layer, a layer of glue needs to be applied on the base surface of the base plate.

[0018] As a preferred method, the rail tooling in the second step is configured according to the double-line 2-hole beam / day work efficiency, L = casting length (4 holes * beam length 32.6m) + lap length (4*4.91m) + casting length * 2 / 3 = 236m≈240m / working surface configuration. The rail and top layer of steel bars must be installed 1 day before concrete pouring and covered with rain and snow.

[0019] As a preferred method, in the second step, the gantry crane crosses the protective wall and moves longitudinally on the running rail at the top of the cable trough, with a span of 10.15m, an effective lifting height of >5m, and can cross the top of the "insulation shed" and the lifting rails on both sides. The gantry crane can be used as a driving force for the forward traction or backward pushing of the insulation shed through a rigid connection.

[0020] Preferably, the fine tuning needs to be performed at night, generally between 0:0 and 5:00, with a single-station measurement length ≤ 70m, and the left and right lines are fine-tuned in parallel. Each station measurement takes 2*2~3h≈5h.

[0021] Preferably, the concrete in the third step is centrally produced by sand, gravel, water reducing agent and water in a mixing plant. The sand and gravel are stored in a silo, the silo is enclosed, and a hot air gun or heating is used to ensure that the temperature of the raw materials is ≥5°C; the water is stored in an indoor pool and heated by an electric heating rod, and the water temperature is ≤60°C. The water reducing agent is stored in barrels indoors, and the indoor air conditioner keeps the temperature ≥5°C. The temperature of the concrete out of the silo should be ≥10°C. The tanker should be preheated with hot water before loading the concrete, and the outside is wrapped with a heat preservation cover to ensure that the temperature of the concrete entering the mold is ≥5°C. The concrete should be poured during the day when the ambient temperature is ≥5°C, generally completed in the time period from 10:00 to 16:00.

[0022] Preferably, the heat preservation shed in the third step includes a color steel tile heat preservation roof, 5 cm square steel longitudinal ribs, 10 cm square steel transverse skeletons, end color steel tile heat preservation gable walls, a thermometer and hygrometer, 5 cm triangular reinforcement square steel, 10 cm rigid connection square steel, D longitudinal traveling rubber wheels, 5 cm square steel guide wheel fixing frames, 10 cm square steel columns, 10 cm square steel longitudinal skeletons, transverse wire rubber wheels, end heat preservation and waterproof cotton quilts, side heat preservation and waterproof cotton quilts and hot air guns, etc.;

[0023] Each section of the heat preservation shed is 11 m long, and the combination is for the heat preservation of a 2-hole box girder and can be moved separately to meet the requirements of removing 2 sections of track slabs, with a length of 6*11m + 1*11m and a span of 9.25 m;

[0024] The traveling wheels are fixed to the 10 cm square steel at the bottom of the heat preservation shed longitudinally. 4 pairs of traveling wheels are set for each section, and 2 main wheels and 2 auxiliary wheels are set for each pair, and they can move longitudinally on the top of the retaining wall. The auxiliary wheels can ensure that the heat preservation shed can smoothly cross the manhole on the retaining wall;

[0025] The guide wheels are attached to the support of the heat preservation shed by square steel and can move longitudinally inside the retaining wall, and ensure that the heat preservation shed does not fall off during longitudinal movement on the retaining wall, and are installed corresponding to the main wheels of the traveling wheels;

[0026] The support of the heat preservation shed is welded by square steel, with a triangular ridge, the cross beam is 1.8 m higher than the beam surface, and the top is 3 m higher than the beam surface, which neither affects the passage of personnel inside the heat preservation shed nor affects the gantry crane to cross the heat preservation shed to hoist the track slab;

[0027] The heat preservation roof is a heat preservation foam color steel tile, and the cotton quilt is a rainproof cotton quilt, which is suspended on both sides of the heat preservation shed, covering 30 cm of the retaining wall, and is suspended at the end to cover the beam surface;

[0028] The hot air guns are installed at both ends of the heat preservation shed, which can ensure that the indoor temperature is 5°C ≤ T ≤ 30°C. A temperature control switch is installed on the power line, which is turned on when the temperature is <5°C and the hot air gun is turned off when it is >30°C;

[0029] The hygrothermograph is suspended on the transverse square steel of the triangular roof ridge, with one installed at each of the two ends and in the middle, and the indoor temperature is not less than 5°C. It is cured for 1 day and sealed for curing before the ambient temperature is <5°C. After subsequent heat storage curing of "plastic film moisture retention + electric blanket heating + waterproof cotton quilt heat insulation", it can be towed forward by a gantry crane for the next process, and the specific cycle time is determined according to the cycle time of the track slab.

[0030] Preferably, for step 8, the insulation shed is towed or pushed by a gantry crane through a 10-cm rigid connecting square steel on the insulation shed. The rigid connecting square steel consists of connecting bolts, connecting steel plates, reinforcing square steel, pins, and a pushing and towing square steel;

[0031] The pushing and towing square steel is welded integrally with the reinforcing square steel and the pin. The other end of the reinforcing square steel is welded to the steel plate. The pushing and towing square steel is inserted into the 10-cm longitudinal square steel at the bottom of the insulation shed through the pin and is bolted to the 10-cm longitudinal square steel through the steel plate to ensure that the force transmission of the gantry crane towing / pushing is on the insulation shed. The rigid connection can be quickly installed and removed to ensure that the gantry crane can pass over the insulation shed.

[0032] Preferably, for step 4, the plastic film is 4 m wide, 100 m long per roll, and has a thickness >0.04 mm (4 mils). The moisture retention not only locks in the moisture of the concrete itself, but also water with a temperature >10°C can be sprayed as needed before covering for water curing to ensure the hydration heat reaction of the concrete.

[0033] Preferably, for step 4, each electric blanket is 4 m wide and 6 m long, is connected in series with the main cable through a socket, and is equipped with a temperature controller;

[0034] The temperature controller includes a probe and a controller. One end of the controller is connected to the probe, and the other end is connected to the input and output terminals of the main power supply. The probe is placed at the bearing platforms of two double-block sleepers of the first track slab for heat storage curing at the power supply input end of the power cord. When the surface temperature of the concrete is 25°C < T, the temperature controller can cut off the main power supply, and when T < 5°C, the power supply is turned on;

[0035] The main power supply is led out from the three-level distribution box in the cable trench, connected to the temperature controller, led out from the other end, and connected in series with multiple plug boards. The main power supply is turned on and off through the temperature controller, and the plug boards can supply power to 4 electric blankets adjacent to the left and right lines.

[0036] Preferably, for step 4, each waterproof cotton quilt is 4 m wide and 6 m long, with the cotton side facing down and the rainproof canvas side facing up for laying.

[0037] Preferably, for step 4, curing for 7 days can ensure that the concrete is not frozen before reaching 60% of the design strength, and continuous curing for 7 days can ensure the later strength growth of the concrete;

[0038] The data of the track support platform is re-measured in a timely manner after the track-laying tooling is removed. During winter construction, the re-measurement is adjusted to be carried out 14 days after curing.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0040] 1. The winter construction heat preservation and curing method for the ballastless track bed slab of high-speed railways provided by the present invention effectively utilizes the gantry crane and power supply used for the ballastless track bed slab, and the protective wall of the box girder's own structure, which meets the requirements of the construction process and the organization and connection of the working procedures for the sectional construction of the track bed slab.

[0041] 2. The tooling adopts a self-made square steel frame heat preservation shed, which is simple to process, has a firm structure, and the sectional assembly can ensure the heat preservation effect of the working procedure. The hot air guns, plastic films, electric blankets, waterproof cotton quilts and temperature control devices used can be purchased in the market and recycled, which can ensure that the work efficiency and quality of 130 m of the track bed per day for a single working face can be achieved during winter, providing a new idea for winter construction of ballastless track construction.

[0042] 3. The present invention combines with the process of the ballastless track bed slab. By controlling the production of the concrete mixing plant, the transportation of the tank truck and the temperature of the concrete entering the mold, after pouring, it is cured for 1 day by "closing the heat preservation shed + heating with hot air guns to raise the temperature", for 7 days by "moisturizing with plastic film + raising the temperature with electric blankets + heat preservation with waterproof cotton quilts", and continuously cured for 7 days by "plastic film + waterproof cotton quilt" and other measures, ensuring that the temperatures of each working procedure during winter construction of the ballastless track bed slab meet the quality control requirements, and high-quality ballastless track construction can be completed during winter, greatly improving the project progress. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, form a part of this application, and do not constitute a limitation to the embodiments of the present invention. In the drawings:

[0044] Figure 1 is the longitudinal sectional view of the winter construction zoning of the straight / curved ballastless track bed slab in the bridge section;

[0045] Figure 2 is the plan view of the winter construction zoning of the straight / curved ballastless track bed slab in the bridge section;

[0046] Figure 3 is the cross-sectional view of the heat preservation shed heat preservation system and the covering curing system;

[0047] Figure 4 is Figure 3 the enlarged view at point A of

[0048] Figure 5 is the cross-section of the track-laying tooling system and the ballastless track bed structure;

[0049] Figure 6 is the plan view of the large sample drawing of the rigid connection;

[0050] Figure 7 It is the large-scale drawing plan of the temperature control switch.

[0051] The reference numerals represent: 1 - gantry crane, 2 - thermal insulation shed, 201 - color steel tile thermal insulation roof, 202 - triangular reinforcing square steel, 203 - square steel column, 204 - side thermal insulation and waterproof cotton quilt, 206 - longitudinal running rubber wheel, 22 - rigid connecting square steel, 2201 - square steel bolt, 2202 - square steel diagonal brace, 2203 - jacking and towing square steel, 2204 - connecting steel plate, 2205 - connecting bolt, 23 - protective wall, 3 - warm air gun, 4 - temperature and humidity meter, 401 - probe, 5 - track panel, 501 - adjustable support leg, 502 - positioning cross beam, 503 - longitudinal rail, 504 - track panel diagonal brace, 505 - fastening fitting, 6 - double-block sleeper, 7 - thermal insulation cotton quilt, 8 - windproof cable, 9 - heating electric blanket, 10 - moisture-proof plastic film, 11 - power cord, 13 - temperature control switch, 14 - steel formwork, 15 - formwork diagonal brace, L1 - track panel assembly area, L2 - bottom layer steel bar binding area of ballast bed, L3 - thermal insulation ballast bed pouring area, L4 - ballast bed heat storage and thermal insulation curing area, L5 - ballast bed thermal insulation curing area. Detailed implementation manners

[0052] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below with reference to the embodiments and the accompanying drawings. The illustrative embodiments and descriptions thereof of the present invention are only used to explain the present invention and shall not be construed as limiting the present invention.

[0053] Embodiment, as Figures 1 to 7 shown, a method for winter construction of ballastless track based on a mobile thermal insulation shed includes the following steps:

[0054] S1: Lay a geotextile isolation layer on the top surface of the ballastless track base, install an elastic cushion layer around the limit groove, and bind the bottom layer steel bars and coating insulation steel bars on the geotextile;

[0055] As Figure 1 and Figure 2 shown, in step S1, the specific steps of the geotextile are as follows:

[0056] S11: Clean the top surface of the base 2 days in advance during the daytime high temperature period (ambient temperature ≥ 5°C), dry it, apply glue with a width of 10 cm horizontally around the perimeter, on the top surface around the limit groove and in the middle of the slab, and apply glue on the bottom of the limit groove, and lay geotextile C6;

[0057] S12. The elastic cushion layer includes an elastic cushion plate and a foam board, which are pre-pasted and combined with tape. The longitudinal A-type cushion plate is 900 mm long, the transverse B-type cushion plate is 600 mm long, 110 mm wide, and 8 mm thick. In winter, in addition to applying a layer of glue on the elastic cushion layer, a layer of glue also needs to be applied to the inner wall of the limit groove. After pasting, use a rubber hammer to tap and paste tightly to avoid the influence of low temperature on the glue pasting effect. Use a binding jig to bind the coated steel bars and install them in the limit groove, and the coating must not be damaged;

[0058] S13. Use insulating clips to bind the bottom steel bars on the geotextile to ensure that the steel bars do not touch each other. The insulation resistance of the insulating binding tape with a tail is > 1 Ω, and immediately cover with a plastic film to prevent rain and snow.

[0059] S2: Complete the work of assembling the track panel 5 on the sleeper separation platform at, and then hoist the track panel 5 to. At, use the gantry crane 1 to hoist the track panel 5 onto the bottom steel bars. Install the steel formwork 14 on both sides of the bottom steel bars. First, roughly adjust the position of the track panel 5 with a fine adjustment trolley and then finely adjust it, collect the original data. Then install the top steel bars and conduct comprehensive grounding, and measure the resistance.

[0060] As Figure 4 shown;

[0061] S21. Install the sleeper separation platform tooling on the base plate, quickly and accurately assemble the track panel 5, and strictly prohibit manual sleeper separation;

[0062] S22. Use the gantry crane 1 to hoist the track panel 5 onto the bottom steel bars, and install the steel formwork 14 around the ballast bed plate;

[0063] S23. Use the fine adjustment trolley to roughly adjust the track panel 5 and complete the fine adjustment at night, collect the original data. The fine adjustment needs to be carried out at night, generally from 0:00 to 5:00. The single-station measurement length ≤ 70 m, and the left and right lines are adjusted in parallel. Each time the station is set up for measurement, it takes 4 - 6 h;

[0064] S24. Install the top steel bars on the track panel 5 and conduct comprehensive grounding;

[0065] S25. Use a megger to measure the resistance. The track panel 5 and the top steel bars need to be installed 1 day before the concrete pouring, and cover to prevent rain and snow to ensure that the concrete is poured during the high-temperature period on the second day.

[0066] Beneficially, the gantry crane 1 moves longitudinally on the running track on the top of the cable trench across the protective wall 23, with a span of 10.15 m and an effective lifting height > 5 m. It can cross the top and both sides of the heat preservation shed 2 to hoist the track panel 5. The gantry crane 1 is connected to the heat preservation shed 2 through a rigid connecting piece. The gantry crane 1 can be used as the power for the forward traction or backward pushing of the heat preservation shed 2, so that it can be driven through the gantry crane 1.

[0067] As Figure 6As shown, the template tooling includes a steel template 14, a template diagonal brace 15 and a positioning steel bar. The template diagonal brace 15 has a ring at one end and a 90° hook at the other end, and the middle is connected by a threaded connection; the diagonal brace hook section is inserted into the back rib hole of the steel template 14, and the ring end is sleeved on the positioning steel bar or horizontally topped on the protective wall 23, and the template position is adjusted by adjusting the threaded connection.

[0068] The positioning steel bars are 20mm diameter threaded steel bars. Use an electric drill to drill a 10cm deep hole on the beam surface and insert the steel bars, leaving 10cm of the steel bars exposed.

[0069] In this embodiment, the rail 5 tooling includes adjustable legs 501, positioning beams 502, longitudinal rails 503, rail braces 504 and buckle accessories 505. The rails are P60kg / m rails, which are consistent with the line rail model, and can ensure that the rail surface elevation after fine adjustment is consistent with the designed rail surface elevation. The longitudinal position of the rail 5 is fixed by the connecting plate. The adjustable legs 501 are connected to the end of the positioning beam 502 by a screw rod, and the height of the rail 5 is adjusted by turning the screw rod; one end of the rail brace 504 is supported on the end of the positioning beam 502, and the other end is supported on the embedded steel bars on the beam surface or the protective wall 23, connected by threads, and the horizontal position of the rail 5 is accurate by adjusting the threads. The track 5 tooling is configured in sections, which can ensure that the spacing between sleepers of different track bed lengths such as 4910mm, 5570, 6200, etc. is 600mm<d<650mm. The track 5 tooling is configured according to the daily work efficiency of double-line 2-hole beams, L=casting length (4 holes*beam length 32.6m)+lap length (4*4.91m)+casting length*2 / 3=236m≈240m / working surface configuration.

[0070] S3. Concrete is centrally produced in the mixing station, transported by tank trucks, poured by pump trucks, and finished; the data is re-measured by the trolley for fine-tuning; the "insulation shed 2 + warm air cannon 3" is used for maintenance. After the concrete has initially set, the rail 5 frame and formwork are removed while the gantry crane 1 is used to pull or push the insulation shed 2 for maintenance to the next cycle.

[0071] In step S3, concrete is centrally produced at the mixing station, sand and gravel are stored in the silo, the silo is closed, and the temperature of the raw materials is ensured to be ≥5°C by using a heater 3 or a heater. The mixing water is stored in an indoor pool and heated by an electric heating rod. The upper limit of the water temperature is 60°C. The water reducer is stored in barrels indoors, and the indoor air conditioning insulation temperature is ≥5°C. The temperature of the concrete out of the silo should be ≥10°C, and the temperature is measured and recorded once in the morning, noon and evening to ensure that the temperature of the raw materials meets the standard.

[0072] Advantageously, the tank truck should be preheated with hot water before loading concrete, and wrapped with an insulation cover on the outside to ensure that the temperature of the concrete entering the mold is ≥5°C. At the same time, the pump truck uses the sidewalk to occupy a position, and the operating radius can cover the concrete pouring of the left and right double-track 4-hole beam roadbed slabs. The height meets the pier height requirements. Concrete pouring should be completed when the ambient temperature is ≥5°C during the day, generally between 10:00 and 16:00.

[0073] In this embodiment, it takes about 3 hours to pour concrete. After 2 hours of initial setting after pouring, the surface is finished, and the original data of the rails are remeasured using a fine-tuning trolley. Before the ambient temperature is less than 0°C, the gantry crane 1 is used to pull the insulation shed 2 to close the track bed slab, and the warm air cannon 3 is turned on for temperature maintenance. About 4 hours after the concrete has finally set, it is moved section by section from back to front, and the insulation shed 2 is removed at a moving distance of 11 m each time. The insulation shed 2 then cleans the surface of the track bed slab, and then covers it with "plastic film + electric blanket + waterproof quilt" for heat storage maintenance. After the rail row 5 and the formwork are completely removed, the initial maintenance of "insulation shed 2 + warm air cannon 3" is transformed into "heat storage maintenance", and the insulation shed 2 can proceed to the next cycle, which is organized as one cycle per day.

[0074] In this embodiment, the insulation shed 2 includes a color steel tile insulation ceiling 201, a triangular reinforced square steel 202, a rigidly connected square steel 22, a longitudinal running rubber wheel 206, a square steel column 203, and a side insulation and waterproof quilt 204. A warm air gun 3 is arranged in the insulation shed 2, and the warm air gun 3 is used to heat the insulation shed 2. The insulation shed 2 moves on the protective wall 23 through the longitudinal running rubber wheels 206.

[0075] Each section of the insulation shed 2 is 11m long. The combined length is 6*11m+1*11m long and the span is 9.25m. The running wheels are fixed under the 10cm square steel at the bottom of the insulation shed 2. Each section is equipped with 4 pairs of running wheels, each pair is equipped with 2 main wheels and 2 auxiliary wheels, and can move longitudinally on the top of the protective wall 23. The auxiliary wheels can ensure that the insulation shed 2 can smoothly cross the manhole on the protective wall 23;

[0076] The guide wheels are attached to the support of the heat preservation shed 2 using 5-cm square steel, capable of longitudinal movement inside the inner side of the protective wall 23, ensuring that the heat preservation shed 2 does not fall during longitudinal movement on the protective wall 23, corresponding to the main wheels of the running wheels. The support of the heat preservation shed 2 is welded by 10-cm and 5-cm square steel, with a triangular ridge roof, the cross beam is 1.8 m higher than the beam surface, and the top is 3 m higher than the beam surface. The heat preservation shed roof is made of heat preservation foam color steel tiles, and the cotton quilt is a rainproof cotton quilt, suspended on both sides of the heat preservation shed 2, covering 30 cm of the protective wall 23, and suspended at the end to cover the beam surface. The warm air guns 3 are installed at both ends of the heat preservation shed 2, capable of ensuring that the indoor temperature is 5℃ ≤ T ≤ 30℃. A temperature control switch 13 is installed on the power line 11, which is turned on when the temperature < 5℃ and the warm air guns 3 are turned off when > 30℃. The thermo-hygrometer 4 is suspended on the transverse square steel of the triangular ridge roof, with one installed at each of the two ends and in the middle. The indoor temperature is not less than 5℃, and the temperature is measured and recorded every 2 hours.

[0077] Cure for 1 day, seal and cure before the ambient temperature < 5℃. After subsequent "plastic film moisture retention + electric blanket temperature increase + waterproof cotton quilt heat preservation" heat storage curing, the gantry crane 1 can be used to tow and move forward for the next process. The specific cycle time is determined according to the cycle time of the track slab.

[0078] As Figure 6 As shown, the rigid connection square steel 22 includes connection bolts 2205, square steel pins 2201, connection steel plates 2204, square steel braces 2202, and push-pull traction square steel 2203, etc. The push-pull traction square steel 2203 is welded into an integral body with the reinforcing square steel and pins. The other end of the reinforcing square steel is welded to the connection steel plate 2204. The push-pull traction square steel 2203 is inserted into the 10-cm longitudinal square steel at the bottom of the heat preservation shed 2 through pins and is bolted to the longitudinal 10-cm square steel through a steel plate, ensuring that the gantry crane 1 transmits the traction or pushing force to the heat preservation shed 2. The rigid connection can be quickly installed and removed to ensure that the gantry crane 1 can pass over the heat preservation shed 2.

[0079] S4. Adopt "plastic film moisture retention + electric blanket temperature increase + waterproof cotton quilt heat preservation" heat storage curing for 7 days, and continue to use "plastic film + waterproof cotton quilt" for heat preservation curing until the 14th day. Measure the data of the rail support table and analyze.

[0080] As Figure 4 As shown, after the track panel 5 tooling and formwork are hoisted and removed, if the surface of the track slab is dry, 10℃ warm water is sprayed for wetting, felt is stuffed into the beam joints, and plastic film is covered. The plastic film is 4 m wide, 100 m long per roll, and the thickness > 0.04 mm (4 mils), covering the track slab comprehensively for moisture retention, locking the moisture of the concrete itself, and ensuring the hydration heat reaction of the concrete;

[0081] As Figure 4As shown, an electric blanket is covered on the plastic film. Each piece of the electric blanket is 4m wide and 6m long, is connected in series with the main power supply through a socket, and a thermostat is set. The thermostat includes a probe 401 and a controller. The controller preferably selects a temperature control switch 13. One end of the temperature control switch 13 is connected to the probe 401, and one end is connected to the input and lead-out end of the main power supply. The probe 401 is placed at the treads of 2 double-block sleepers 6 of the first heat storage curing roadbed slab at the input end of the power cord 11. When the concrete surface temperature 25°C < T, the thermostat can disconnect the main power supply, and when T < 5°C, it connects the power supply for heating.

[0082] The main power supply is led out from the three-level distribution box in the cable trench, connected to the thermostat, led out from the other end, connected in series with multiple plug boards, and the main power supply is turned on and off through the thermostat. The plug boards can supply power to 4 adjacent electric blankets on the left and right lines.

[0083] A waterproof cotton quilt is laid on the electric blanket. Each piece of the cotton quilt is 4m wide and 6m long, with the cotton side facing down and the rainproof canvas side facing up. Windproof cable ropes 8 and sandbags are installed on the cotton quilt to prevent the cotton quilt from being blown up. Digital display thermometer probes 401 are installed at the treads between two sleepers. The thermometer is placed flat on the cotton quilt, and the temperature is measured once every 2 hours and records are made.

[0084] Maintaining for 7 days can ensure that the concrete is not frozen before reaching 60% of the designed strength. The continuous maintenance for 7 days can ensure the later growth strength of the concrete.

[0085] Data of the bearing block are usually re-measured in time after removing the track-laying 5 tooling, and in winter construction, it is adjusted to be re-measured after removing the covering 14 days after maintenance.

[0086] According to the above invention, it can ensure the construction quality and construction efficiency of the ballastless track roadbed slab in winter. The curing effect is confirmed by making 3d, 7d and 14d same-condition test blocks for pressure testing and in-situ rebound.

[0087] The above specific implementation manners further elaborate the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only the specific implementation manners of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A winter construction method for ballastless track based on a mobile insulation shed, characterized in that: The steps include: S1: Lay a geotextile isolation layer on the top surface of the ballastless track base, install an elastic cushion around the limit groove after the geotextile isolation layer is laid, and then tie the bottom steel bars and coated insulating steel bars on the geotextile; S2: Assemble the rail row (5) on the sleeper platform, use the gantry crane (1) to hoist the rail row (5) onto the bottom steel bar, install the steel template (14), use the fine adjustment trolley to perform rough and fine adjustment on the installation position of the rail row (5) to ensure that the rail row (5) is installed in place, collect the original installation data, then install the top steel bar and comprehensive grounding, and measure the resistance; S3: Concrete is centrally produced in the mixing station, transported by tank trucks, poured by pump trucks, and finished after pouring. The installation position data is re-measured by a fine-tuning trolley, and maintained by "insulation shed (2) + warm air gun (3)". After the initial setting of the concrete, the rail (5) frame and formwork are removed, and the gantry crane (1) is used to pull or push the insulation shed (2) for maintenance until the next cycle; S4: Adopt "plastic film for moisture retention + electric blanket for heating + waterproof quilt for heat preservation" for 7 days of heat storage and curing. After 7 days of heat storage and curing, continue heat preservation and curing with "plastic film + waterproof quilt" until the 14th day; S5: Measure the data of the rail support platform and analyze the construction quality based on the test data.

2. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: In step S1: The geotextile and elastic cushion layer are laid during the hottest period of the day after the base surface is cleaned and dried 2 days before pouring the ballast slab, and the ambient temperature during the hottest period is ≥5°C. After laying, they are covered with rain and snow protection facilities for protection. Before installing the elastic cushion layer, a layer of glue needs to be applied on the base surface of the base plate.

3. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: The rail (5) is configured according to the daily work efficiency of a double-line two-hole beam. The rail (5) and the top layer of steel bars need to be installed one day before concrete pouring and covered to prevent rain and snow.

4. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: In step S2, the gantry crane (1) crosses the protective wall (23) and moves longitudinally on the running rail at the top of the cable trough, with a span of 10.15m and an effective lifting height of >5m. It can cross the top and the lifting rails (5) on both sides of the insulation shed (2). The gantry crane (1) is rigidly connected to the insulation shed (2) and can serve as a power for pulling the insulation shed (2) forward or pushing it backward.

5. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: The said fine tuning needs to be done at night, from 0:00 to 5:00 in winter (18:00-23:00 in summer), the measurement length of a single station is ≤70m, the left and right lines are fine tuned in parallel, and each station measurement takes 4-6 hours.

6. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: In step S3, the concrete is centrally produced from sand, crushed stone, water reducing agent and water using a mixing station. The sand and crushed stone are stored in a silo, which is sealed. A warm air gun (3) or a heater is used to ensure that the temperature of the raw materials is ≥5°C. The water is stored in an indoor pool and heated by an electric heating rod. The water temperature is ≤60°C. The water reducing agent is stored in barrels indoors. The indoor air conditioner is kept warm at ≥5°C. The temperature of the concrete out of the silo should be ≥10°C. The tank truck should be preheated with hot water before loading the concrete. The tank truck should be wrapped with a heat preservation cover to ensure that the temperature of the concrete entering the mold is ≥5°C. The pouring of concrete is completed when the ambient temperature during the day is ≥5°C, generally between 10:00 and 16:

00.

7. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: In step S3, each section of the insulation shed (2) is 11m long, and the combined length is combined according to the distance of the two-hole box beam. After the combination, the insulation is carried out and the two sections of rails (5) are removed separately to meet the removal requirements. The span of the insulation shed is 9.25m; The bottom of the heat preservation shed (2) is provided with running wheels, each section is provided with 4 pairs of running wheels, each pair is provided with 2 main wheels and 2 auxiliary wheels, and can move longitudinally on the top of the protective wall (23), and the auxiliary wheels can ensure that the heat preservation shed (2) can smoothly cross the manhole on the protective wall (23); The guide wheel is attached to the bracket of the heat preservation shed (2) by means of square steel, can move longitudinally inside the protective wall (23), and ensures that the heat preservation shed (2) does not fall off when moving longitudinally on the protective wall (23), and is installed at the position of the main wheel of the running wheel; The support of the insulation shed (2) is welded from square steel, with a triangular ridge, a crossbeam 1.8m higher than the beam surface, and a top 3m higher than the beam surface; The insulation ceiling is an insulation foam colored steel tile, and the quilt is a rainproof quilt, which is hung on both sides of the insulation shed (2). The lower end of the rainproof quilt covers the protective wall (23) by 30 cm and is hung at the end to cover the beam surface; The heating gun (3) is placed at both ends of the heat preservation shed (2) to ensure that the temperature in the shed is 5°C ≤ T ≤ 30°C. A temperature control switch (13) is installed on the power line (11) to turn on when the temperature is less than 5°C and turn off when the temperature is greater than 30°C. The thermohygrometer (4) is hung on the horizontal square steel of the triangular roof ridge, with one set at each end and the middle. The indoor temperature is not less than 5°C and maintained for 1 day. It is closed and maintained before the ambient temperature is less than 5°C. After the subsequent "plastic film moisturizing + electric blanket heating + waterproof quilt insulation" heat storage maintenance, the door crane (1) can be used to pull forward to carry out the next process. The specific cycle time is determined according to the cycle time of the track bed plate.

8. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1 is characterized in that: In step S3, the heat preservation shed (2) is pulled or pushed by the door crane (1) and moved by a 10 cm rigid connection square steel (22) on the heat preservation shed (2). The rigid connection square steel (22) comprises a connection bolt (2205), a connection steel plate (2204), a reinforcement square steel, a latch and a push-pull square steel (2203); The pushing and pulling square steel (2203) is welded to the reinforcing square steel and the latch into a whole, and the other end of the reinforcing square steel is welded to the steel plate. The pushing and pulling square steel (2203) is inserted into the longitudinal 10 cm square steel at the bottom of the insulation shed (2) through the latch, and is connected to the longitudinal 10 cm square steel bolts through the steel plate to ensure that the door crane (1) pulls or pushes to transmit force to the insulation shed (2). The rigid connection can be quickly installed and removed to ensure that the door crane (1) can pass through the insulation shed (2).

9. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1, characterized in that: In step S4, the plastic film is 4m wide, 100m long / roll, and >0.04mm thick (4 filaments). The moisturizing film not only locks the moisture of the concrete itself, but also sprays water with a temperature of >10°C for curing before covering to ensure the thermal reaction of concrete hydration.

10. The winter construction method of ballastless track based on a mobile insulation shed according to claim 1, characterized in that: In step S4, each of the electric blankets is 4m wide and 6m long, connected in series with the main cable through a socket, and a thermostat is set; each of the waterproof quilts is 4m wide and 6m long, with one side being a quilt and the other side being a rainproof canvas, and when laying, the rainproof canvas is laid upwards; The temperature controller comprises a probe (401) and a controller, one end of the controller is connected to the probe (401), and the other end is connected to the input and output ends of the main power supply, the probe (401) is placed at the input end of the power line (11) at the rail support platform of two double-block sleepers (6) of the first heat storage maintenance track bed plate, and when the concrete surface temperature T is greater than 25°C, the temperature controller can disconnect the main power supply, and when T is less than 5°C, the power supply can be turned on; The data of the rail support platform is usually re-measured in time after the rail panel (5) tooling is removed, and the winter construction is adjusted to re-measured after 14 days of maintenance; The main power supply is led out from the three-level distribution box of the cable trough, connected to the thermostat, and led out from the other end. Multiple plug boards are connected in series. The main power supply is turned on and off by the thermostat. The plug board can power four electric blankets adjacent to the left and right lines.

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