Construction method of guard rail type ballastless track bed

Abstract

The invention relates to the technical field of railway ballastless track bed construction, in particular to a guard rail type ballastless track bed construction method. Comprising the steps of construction preparation, survey lofting and foundation mark survey setting, beam surface chiseling cleaning, sleeve connecting steel bar installation, base steel bar binding, bridge expansion joint embedded part installation, base and groove formwork installation, base concrete pouring and maintenance, isolation layer geotechnical cloth and elastic base plate laying, groove insulation steel bar framework installation and ballast bed bottom layer steel bar binding. The method comprises the following steps of: distributing double-block type sleepers, transporting tool rails, assembling double-block type track panels, roughly adjusting track lifting of the double-block type track panels, binding steel bars on the upper layer of a track bed, distributing guard wheel sleepers, assembling guard wheel track panels, roughly adjusting the sizes of the guard wheel track panels, mounting and adjusting track bed templates, finely adjusting the double-block type track panels for the first time, adjusting the sizes of the guard wheel track panels, and finely adjusting the double-block type track panels for the second time. The method comprises the steps of guard rail row size rechecking, ballast bed concrete pouring, stress relief, concrete curing and data acquisition.

Description

Technical Field

[0001] The invention relates to the technical field of railway ballastless track ballast bed construction, in particular to a wheel guard rail type ballastless track bed construction method. Background Art

[0002] With the gradual construction and improvement of the high-speed railway network, the railway networks are intertwined, and new railway lines cross over existing or operating railways. Generally, the track type of the railway under construction adopts a ballastless track bed structure. When the ballasted railway crosses the operating line, the ballastless track bed structure is adopted to avoid safety impact on the operating line during construction. In particular, when crossing over the busy line of an existing high-speed railway, wheel guard rails are installed in the ballastless track structure to ensure that the operating line below can operate normally after the crossing railway line derails.

[0003] At present, there are three ways to set up the wheel guard rail for ballastless track at home and abroad:

[0004] The first type of cast-in-place rail bearing platform is to cast the rail bearing platform by roughening, planting reinforcement, and casting concrete in place between the railbed slabs after the ballastless slab is cast and formed, and then install wheel guard rails. It is mainly used in the transition section between ballasted and ballastless.

[0005] The second type is the concrete long sleeper type, which is mainly a ballasted and ballastless transition section sleeper. The bonding surface between the sleeper and the cast-in-place concrete is large, and defects such as separation are prone to occur.

[0006] The third derivative type is the double-block sleeper, which is used on German high-speed railways crossing highways. The clearance between the guard rail and the basic rail is small, and the contact area between the double-block sleeper and the concrete is reduced;

[0007] This scheme combines the advantages and disadvantages of ballastless track wheel guard rails at home and abroad, overcomes the existing technical difficulties, and adopts a prefabricated wheel guard rail sleeper without affecting the structural form of the ballastless track bed. The installation operation is carried out simultaneously with the ballastless track bed construction, forming a whole with the ballastless track bed, providing a new ballastless track wheel guard rail construction method, and providing an important reference for the future construction of ballastless track beds across existing railways. Summary of the invention

[0008] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for constructing a wheel guard rail type ballastless track bed.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] In a first aspect, the present invention provides a method for constructing a wheel guard rail type ballastless track bed, comprising: construction preparation steps, surveying and setting out and benchmarking steps, beam surface chiseling and cleaning steps, sleeve connection steel bar installation steps, base steel bar tying steps, bridge expansion joint embedded parts installation steps, base and groove template installation steps, base concrete pouring and curing steps, isolation layer geotextile and elastic pad laying steps, groove insulation steel bar skeleton installation steps, track bed bottom steel bar tying steps, double block sleeper scattering steps, tool rail transportation and double block rail row assembly steps, double block rail row track lifting rough adjustment steps, track bed upper steel bar tying steps, wheel guard sleeper scattering steps, wheel guard rail row assembly steps, wheel guard rail row size rough adjustment steps, track bed template installation and adjustment steps, double block rail row fine adjustment first time step, wheel guard rail row size adjustment step, double block rail row fine adjustment second time step, wheel guard rail row size verification step, track bed concrete pouring step, stress release and concrete curing steps, data collection steps;

[0011] Among them, the steps of spreading wheel guard sleepers are:

[0012] After the rough adjustment of the double-block rail and the tying of the upper steel bars of the ballast are completed, the wheel guard sleepers are transported by a small flat car and spread to the center line of the line between the double-block sleepers. Pay attention to whether there is a position conflict between the steel bars at the bottom of the wheel guard sleepers and the steel bars at the upper layer of the ballast. Otherwise, the position of the steel bars at the upper layer of the ballast should be adjusted to avoid damage to the insulating steel bars of the wheel guard sleepers.

[0013] Assembly steps of wheel guard rail:

[0014] Place the wheel guard rail sleeper bottom pad, use a manual gantry crane to place the rails placed on the double-block rail sleeper platform onto the wheel guard rail sleeper, install bolts, washers and other fasteners and tighten them preliminarily with a T-wrench, connect adjacent rails with fishplates, and install screw adjusters at both ends of each unit plate;

[0015] Steps for rough adjustment of guard rail:

[0016] The geometrical dimension control accuracy of the wheel guard rail is lower than that of the double-block rail. The wheel guard rail is roughly adjusted based on the reference stock of the double-block rail. The adjustment sequence is direction first and then elevation.

[0017] Elevation: Use the screw adjusters at both ends of the unit plate to adjust the direction and elevation of the rail. Use a tape measure and a square ruler to check the direction and elevation of the guard rail. The adjustment error should be controlled within ±10mm.

[0018] Steps for adjusting the size of the guard rail:

[0019] After the first fine adjustment of the double-block rail is completed, the wheel guard rail size is adjusted immediately. The adjustment steps are also based on the double-block rail reference stock, first the direction and then the elevation, and the adjustment error is controlled within ±5mm. After the adjustment is completed, a 530mm square timber is used between the wheel guard rail and the mainline rail, and a 400mm square timber is used between the two wheel guard rails. The square timber is placed at the waist of the rail. After the placement is completed, the double-block rail and the wheel guard rail form an integral structure.

[0020] Steps for checking the size of the guard rail:

[0021] After the second fine-tuning of the double-block track is completed, the geometric dimensions of the wheel guard rail are promptly reviewed and checked. The inspection is completed quickly using a self-made inspection tool, and the positions that do not meet the requirements are adjusted in time. The wheel guard rail dimension review should not disturb the track, and the dimension inspection and review requirements must be completed quickly to leave sufficient time for the pouring of the ballast bed concrete.

[0022] Preferably, it includes the construction preparation steps:

[0023] The construction preparation of wheel guard rail ballastless track is also a complex project. It requires comprehensive consideration of the construction environment, the selection of construction schemes, the logistics and transportation issues of the entire construction process, the bridge elevation review, the construction sequence of each process and the pouring method, and preparations must be made in advance.

[0024] Selection of construction scheme:

[0025] The project is located above an existing busy high-speed railway, and the line is a single-track railway. The operation management unit requires that large equipment be avoided as much as possible to avoid safety impacts on the operating line;

[0026] At present, the construction of double-block ballastless track mainly adopts the frame method and the tool rail method. The frame method occupies the space between the double-block sleepers, which makes it impossible to assemble the wheel guard rail. Therefore, the tool rail method is selected as its construction method.

[0027] Logistics transportation method:

[0028] Ballastless track logistics transportation is divided into internal logistics transportation and external logistics transportation;

[0029] Internal logistics transportation refers to the transportation of materials, equipment and tools within the construction section. The order of transfer of materials and tools should be organized and planned according to the needs of the construction section ahead;

[0030] External logistics transportation refers to the transportation from the outside of the construction section to the construction section. All materials, equipment and tools should be carefully planned and organized according to the overall construction process, especially the construction organization of the first section. Because it is a single-line construction, materials, equipment and tools cannot be piled up too much on site, and can only be carried out step by step according to the construction process requirements. Excessive stacking and premature transportation will directly affect the construction progress on site;

[0031] The entire logistics and transportation guarantee is the key to the progress control of ballastless track construction. The early construction preparation work is arduous, and careful planning and preparation are required to ensure the flow of construction technology and progress requirements;

[0032] Choice of concrete pouring method:

[0033] To be precise, it is also a link in logistics transportation. According to the site conditions, this project adopts a sky pump outside the influence range of the existing line to pump it to the vehicle-mounted pump above the bridge, and then transports it to the construction site by the vehicle-mounted pump. The pouring method is to dismantle the pipe from the far end to the near end.

[0034] Before the construction of the ballastless track bed project, the bridge elevation shall be reviewed according to the CPⅢ result control points, and the cutting size of the base steel bars shall be based on the actual bridge elevation; the template selection shall be based on the actual elevation.

[0035] Preferably, it includes the steps of surveying and setting out and benchmarking:

[0036] After the work surface is handed over, the positions of each base plate and the center line of the line are marked according to the CPⅢ measurement control network, and the base point is measured on the outside of the base plate, and a base mark is set every 5m and buried firmly;

[0037] Including the steps of chiseling and cleaning the beam surface:

[0038] Pop up the base edge line according to the position of the released base plate, and chisel and clean the beam surface within the range of the base plate. The chiseling depth should be ≥2mm, and the newly exposed concrete area should not be less than 75%. When chiseling, check the number of reserved sleeves on the beam surface and mark the missing or damaged ones on site;

[0039] It includes the installation steps of sleeve connection steel bar:

[0040] Remove the sleeve cap on the beam surface, clean up the debris in the sleeve, screw the processed L-shaped connecting steel bar into the sleeve, and tighten it with a torque wrench according to the designed torque value. For damaged or missing embedded sleeves, drill holes on both sides of the sleeve setting position, and implant the L-shaped steel bars for embedding, with the implantation depth meeting the requirements.

[0041] Preferably, it includes the steps of tying the base reinforcement:

[0042] According to the design drawings, use ink lines to pop out all the longitudinal and transverse steel bar position lines and the base groove position lines. The steel bars are placed and tied according to the popped-out steel bar line positions. After the lower steel bars are tied, the concrete pads are placed at ≮㎡ / 4. After completion, the upper steel bars are tied.

[0043] It includes the installation steps of embedded parts of bridge expansion joints:

[0044] After the base reinforcement is tied, straighten the embedded gate-shaped reinforcement at the beam end, install and tie the expansion joint reinforcement at the beam end, and install the expansion joint steel at the beam end simultaneously. After the expansion joint steel on both sides of the beam end is installed, check whether the beam joint width meets the design requirements and whether the steel is firmly fixed;

[0045] It includes the steps for installing the base and groove template:

[0046] Install the base template according to the base edge line. Each plate should be equipped with a corresponding template. The templates are firmly connected with bolts. The installation order is longitudinal template first and then transverse template. The concrete elevation control points are affixed on the template according to the measurement data of each plate.

[0047] The groove template is assembled first. The groove template is mainly composed of a cross stretcher and a groove template. The cross stretcher and the groove template are connected as a whole by 4 16mm diameter screw rods. When assembling, pay attention to the matching use of the longitudinal and transverse groove templates and cross stretchers. Lift the assembled groove template to the groove installation position, align it according to the groove position line marked on the beam surface, determine the horizontal position of the groove template, use a U-shaped card to fix the cross stretcher on the base template, and use the concrete elevation control point on the base template to adjust it into place by pulling the wire with the screw rod on the groove template;

[0048] It includes the steps of pouring and curing the concrete base:

[0049] The concrete is transported to the construction site and poured by a combination of a sky pump and a vehicle-mounted pump. During the pouring process, the two should cooperate well with each other and be directed by the same person. The concrete pouring should be done from the bottom to the top longitudinally and from the inside to the outside of the curve horizontally. Do not collide with the groove template during the pouring process. The concrete elevation is based on the control point on the template. It is done manually or with a finishing machine. After the finishing is completed, the elevation dimensions should be installed to check and confirm the base elevation. The elevations of the two adjacent base plates should be checked one by one to ensure that the base elevation is controlled within ±10mm and the flatness is 3mm / m.

[0050] After the concrete has finally set, apply concrete curing agent. The curing agent should be applied evenly and water should be sprinkled in time to ensure that the concrete is fully cured. The curing days should be no less than 7 days.

[0051] Preferably, it includes the steps of laying the isolation layer geotextile and the elastic pad:

[0052] Clean the base and groove, check the flatness and size, and lay the isolation layer geotextile after meeting the requirements. The geotextile should be laid flat, without wrinkles or damage. It is strictly forbidden to overlap the geotextile on the same board. Use tape to fix the geotextile on the base around the base; draw the groove edge line according to the groove position, cut it, put the geotextile at the groove position into the groove, lay elastic pads around the groove, and seal and fix it with the geotextile with tape;

[0053] It includes the steps of installing the grooved insulated steel reinforcement frame:

[0054] Tie the processed grooved insulated steel bars to the grooved steel bars to form a steel bar skeleton, place the tied grooved insulated steel bar skeleton in the groove, and place concrete pads at the bottom of the skeleton. The number of pads is ≮㎡ / 4;

[0055] It includes the following steps for tying the reinforcement bars of the ballast bottom layer:

[0056] Mark the positions of the longitudinal and transverse ballast steel bars on the geotextile, place the processed semi-finished ballast steel bars neatly according to the marked positions, and use insulating cards or insulating ties to tie and fix the longitudinal and transverse steel bar nodes. During the tying process, it is strictly forbidden for the steel bars to damage or move the geotextile.

[0057] Preferably, it comprises the steps of spreading the twin-block sleepers:

[0058] The double-block sleepers are hoisted onto the bridge and are manually lifted to the installation position on the bottom steel bar of the ballast bed. The double-block sleepers are preliminarily squared according to the centerline of the ballast bed. After completion, the elastic pads, half-point posts, blocks, spikes and springs of the double-block sleepers are installed. The springs should be placed at the block position and should not occupy the rail installation position.

[0059] Including tool rail transportation and double-block rail assembly steps:

[0060] The tool rail is transported to the installation location by two self-made simple transport gantries. After the steel rail is transported to the location, the double-block sleeper is squared, and two steel rails are placed in the grooves on the double-block sleeper. A steel rail is placed at each step position of the double-block sleeper to assemble the rails as the wheel guard rail row. The number of steel rails in the wheel guard rail row is the same as that of the double-block rail row.

[0061] Draw the sleeper spacing line on the rail, square the sleepers accurately, install spring bars, tighten spike bolts to connect the rails to the sleepers; install screw adjusters between the first and second sleepers at the rail end and every 4 to 5 sleepers for the remaining sleepers, use fish plates to connect adjacent tool rails firmly, and control the rail gap to about 20mm;

[0062] It includes the steps of rough adjustment of double-block track arrangement:

[0063] The track is roughly adjusted according to the measurement data of the base mark points. The L ruler and the track gauge are used to raise the track to about 5mm below the elevation value, and the direction of the track is adjusted. After the direction is adjusted in place, the elevation is adjusted, the track gauge is verified, and the gauge support rods and lateral support rods are installed. After the track adjustment is completed, the track error is controlled within: direction ±2mm, elevation 0~-2mm, gauge ±1mm, and the change rate is 1 / 1000.

[0064] Preferably, it includes the step of tying the upper reinforcement bars of the ballast:

[0065] Transfer the upper steel bars of the track bed to the construction location, arrange the upper steel bars of the track bed according to the design requirements, and use insulating cards or insulating straps to firmly tie the steel bars at the intersection of the longitudinal and transverse steel bars. The roughly adjusted double-block rails must not be disturbed during the steel bar tying process. After the steel bars are tied, weld the grounding steel bars and grounding terminals. Take protective measures during welding to avoid burns and damage to the geotextile; after the upper steel bars are tied, promptly place the reinforced concrete pads of the track bed bottom layer, and the number of pads is ≮㎡ / 4;

[0066] It includes the steps of trackbed formwork installation and adjustment:

[0067] Select matching ballast plate templates according to different ballast plate lengths. The installation order is longitudinal template first and then transverse template. The bottom of the template is firmly supported by square wood to prevent the template from hanging in the air. Check the plate size and verticality and make timely adjustments. The spacing between adjacent ballast plates and the ballast plates on both sides of the expansion joints must meet the requirements.

[0068] Preferably, it includes a first pass step of double-block track arrangement fine-tuning:

[0069] The double-block track is fine-tuned through the CPⅢ track control network using a total station and a track fine-tuning trolley. The direction, superelevation and elevation are adjusted by adjusting the screw adjuster and the lateral support rod. After the fine-tuning is completed, the adjustment error is controlled within: direction ±1mm, elevation 0~-0.5mm, track gauge ±0.5mm, and the change rate is 1 / 1000.

[0070] It includes the second pass of double-block track adjustment:

[0071] The second fine-tuning of the double-block track is carried out after the size adjustment of the guard rail is completed to ensure that the geometric state of the track meets the requirements. The fine-tuning method is the same as the first fine-tuning. After the fine-tuning is completed, the adjustment error is controlled within: direction ±1mm, elevation 0~-0.5mm, track gauge ±0.5mm, and the change rate is 1 / 1000; after the fine-tuning is completed, the ballast bed concrete pouring should be completed within 12 hours.

[0072] Preferably, it comprises the steps of pouring ballast concrete:

[0073] Before pouring the ballast bed, the surfaces of the double-block sleepers, wheel guard sleepers and geotextiles should be fully moistened and free of water accumulation. When the concrete is transported to the site, it should be pumped into the vehicle-mounted pump by a sky pump and then transported to the pouring point by the vehicle-mounted pump. The pouring method should be from far to near, and the pouring should be done while removing the pipes. During the pouring process, attention should be paid to the vibration of the concrete under the double-block sleepers and wheel guard sleepers to ensure that the concrete under the sleepers is dense. The finishing of the concrete should focus on the control of the concrete elevation of the bottom of the rail, around the sleepers and adjacent slabs to ensure the finishing quality.

[0074] It includes stress relief and concrete curing steps:

[0075] After the initial setting of the ballast concrete, the fishplate and bolts shall be removed in time to avoid the stress transfer of the rails; according to the test determination method, after the concrete reaches the specified strength, the fasteners shall be loosened in time, and the loosening of the fasteners shall be carried out by jump release to release the stress of the rails in time; before the final setting of the concrete, the screw adjuster shall be loosened by 1 / 2 turn;

[0076] The final finishing should be completed before the final setting of the concrete. After completion, the concrete curing agent should be applied in time and watering should be carried out in time. The curing time of the roadbed concrete should not be less than 14 days.

[0077] Preferably, it comprises the data collection steps:

[0078] On the second day after the concrete pouring is completed, the track geometry data should be collected in time using a fine-tuning trolley in conjunction with a total station. This can timely analyze the track geometry and provide a basis for subsequent process improvements and line fine-tuning. It is strictly forbidden to remove the tool rail before data collection.

[0079] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0080] The invention can be used to master the wheel guard rail type ballastless track bed construction technology, which has high construction efficiency, controllable quality, low safety risk, low cost, strong operability, and can be widely promoted and applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Figure 1 It is a flow chart of a wheel guard rail type ballastless track bed construction method of the present invention; DETAILED DESCRIPTION

[0082] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0083] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all based on the expression of the orientation or position relationship shown in the drawings, or are the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0084] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0085] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0086] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0087] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0088] Example 1

[0089] like Figure 1 As shown, a wheel guard rail type ballastless track bed construction method adopted in this embodiment comprises the following steps:

[0090] a. Construction preparation:

[0091] The construction preparation of the wheel guard rail type ballastless track is also a systematic and complex project. It is necessary to comprehensively consider the construction environment, the selection of construction schemes (in accordance with the requirements of the railway bureau), the logistics and transportation issues of the entire construction process (internal and external logistics and transportation), the bridge elevation review, the construction sequence of each process and the pouring method, and make preparations in advance.

[0092] Selection of construction scheme:

[0093] The project is located above an existing busy high-speed railway, and the line is a single-track railway. The operation management unit requires that large equipment be avoided as much as possible to avoid safety impacts on the operating line.

[0094] At present, the construction of double-block ballastless track mainly adopts the frame method and tool rail method. In the frame method, the frame occupies the space between the double-block sleepers, which makes it impossible to assemble the wheel guard rail. Therefore, the tool rail method is selected as its construction method.

[0095] Logistics transportation method:

[0096] Ballastless track logistics transportation is divided into internal logistics transportation and external logistics transportation.

[0097] Internal logistics transportation refers to the transportation of materials, equipment and tools within the construction section. The order of material and tool transfer should be organized and planned according to the needs of the construction section ahead.

[0098] External logistics transportation refers to the transportation from the outside of the construction section to the construction section. All materials, equipment and tools should be carefully planned and organized according to the overall construction process, especially the construction organization of the first section. Because it is a single-line construction, materials, equipment and tools cannot be piled up too much on site, and can only be carried out step by step according to the construction process requirements. Excessive stacking and premature transportation will directly affect the construction progress on site.

[0099] The entire logistics and transportation guarantee is the key to the progress control of ballastless track construction. The early construction preparation work is arduous. Careful planning and preparation in advance are necessary to ensure the flow of construction technology and progress requirements.

[0100] Choice of concrete pouring method:

[0101] To be precise, it is also a link in logistics transportation. According to the site conditions, this project adopts the sky pump outside the influence range of the existing line to pump to the vehicle-mounted pump above the bridge, and then transports it to the construction site by the vehicle-mounted pump. The pouring method is to pour from the far end to the near end by dismantling the pipe.

[0102] Before the construction of ballastless track bed, the bridge elevation shall be reviewed according to the control points of CPⅢ results. The size of the base steel bar cutting shall be based on the actual bridge elevation. The template selection shall be based on the actual elevation.

[0103] b. Surveying, setting out and benchmarking:

[0104] After the work surface is handed over, the positions of each base plate and the center line of the line are marked according to the CPⅢ measurement control network, and the base point is measured on the outside of the base plate, and a base mark is set every 5m and buried firmly;

[0105] c. Chiseling and cleaning of beam surface:

[0106] Pop up the base edge line according to the position of the released base plate, and chisel and clean the beam surface within the range of the base plate. The chiseling depth should be ≥2mm, and the newly exposed concrete area should not be less than 75%. When chiseling, check the number of reserved sleeves on the beam surface and mark the missing or damaged ones on site;

[0107] d. Installation of sleeve connection steel bars:

[0108] Remove the sleeve cap on the beam surface, clean the sleeve debris, screw the processed L-shaped connecting steel bar into the sleeve, and tighten it with a torque wrench according to the designed torque value after screwing in; for damaged or missing embedded sleeves, drill holes on both sides of the sleeve setting position, and implant the L-shaped steel bars for embedding, and the implantation depth meets the requirements;

[0109] e. Base reinforcement binding:

[0110] According to the design drawings, use ink lines to pop out all the longitudinal and transverse steel bar position lines and the base groove position lines. The steel bars are placed and tied according to the popped-out steel bar line positions. After the lower steel bars are tied, the concrete pads are placed according to ≮㎡ / 4 (≮ means "≥"), and then the upper steel bars are tied after completion;

[0111] f. Installation of embedded parts for bridge expansion joints:

[0112] After the base reinforcement is tied, straighten the embedded gate-shaped reinforcement at the beam end, install and tie the expansion joint reinforcement at the beam end, and install the expansion joint steel at the beam end simultaneously. After the expansion joint steel on both sides of the beam end is installed, check whether the beam joint width meets the design requirements and whether the steel is firmly fixed;

[0113] g. Installation of base and groove template:

[0114] Install the base template according to the base edge line. Each plate should be equipped with a corresponding template. The templates are firmly connected with bolts. The installation order is longitudinal template first and then transverse template. The concrete elevation control points are affixed on the template according to the measurement data of each plate.

[0115] The groove template is assembled first. The groove template is mainly composed of a cross stretcher and a groove template. The cross stretcher and the groove template are connected as a whole by 4 16mm diameter screw rods. When assembling, pay attention to the matching use of the longitudinal and transverse groove templates and cross stretchers. Lift the assembled groove template to the groove installation position, align it according to the groove position line marked on the beam surface, determine the horizontal position of the groove template, use a U-shaped card to fix the cross stretcher on the base template, and use the concrete elevation control point on the base template to adjust it into place by pulling the wire with the screw rod on the groove template;

[0116] h. Pouring and curing of base concrete:

[0117] The concrete is transported to the construction site and poured using a combination of a sky pump and a vehicle-mounted pump. During the pouring process, the two must cooperate well with each other and be directed by the same person. The concrete pouring should be done from the bottom to the top longitudinally and from the inside to the outside of the curve horizontally. Do not collide with the groove formwork during the pouring process. The concrete elevation is based on the control points on the formwork. It is done manually or with a finishing machine. After the finishing is completed, the elevation dimensions should be installed to check and confirm the base elevation. The elevations of the two adjacent base plates should be checked one by one to ensure that the base elevation is controlled within ±10mm and the flatness is 3mm / m.

[0118] After the concrete has finally set, apply concrete curing agent. The curing agent should be applied evenly and water should be sprinkled in time to ensure that the concrete is fully cured. The curing days should be no less than 7 days.

[0119] i. Laying isolation layer geotextile and elastic pad:

[0120] Clean the base and groove, check the flatness and size, and lay the isolation layer geotextile after meeting the requirements. The geotextile should be laid flat, without wrinkles or damage. It is strictly forbidden to overlap the geotextile on the same board. Use tape to fix the geotextile on the base around the base; draw the groove edge line according to the groove position, cut it, put the geotextile at the groove position into the groove, lay elastic pads around the groove, and seal and fix it with the geotextile with tape;

[0121] j. Install the grooved insulating steel frame:

[0122] Tie the processed grooved insulated steel bars to the grooved steel bars to form a steel bar skeleton, place the tied grooved insulated steel bar skeleton in the groove, and place concrete pads at the bottom of the skeleton. The number of pads is ≮㎡ / 4 (≮ means "≥");

[0123] k. Tie-up of reinforcement for the bottom layer of the ballast:

[0124] Mark the longitudinal and transverse ballast steel bar positions on the geotextile, place the processed ballast steel bar semi-finished products neatly according to the marked positions, and use insulating cards or insulating tie bands to tie and fix the longitudinal and transverse steel bar nodes. During the tying process, it is strictly forbidden for the steel bar to damage or move the geotextile;

[0125] 1. Distributed double-block sleepers:

[0126] The double-block sleepers are hoisted onto the bridge and are manually lifted to the installation position on the bottom steel bar of the ballast bed. The double-block sleepers are preliminarily squared according to the centerline of the ballast bed. After completion, the elastic pads, half-point posts, blocks, spikes and springs of the double-block sleepers are installed. The springs should be placed at the block position and should not occupy the rail installation position.

[0127] m. Tool rail transportation and double-block rail assembly:

[0128] The tool rails are transported to the installation location using two self-made simple transport gantries. After the rails are transported to the location, the double-block sleepers are squared, and the two rails are slotted onto the double-block sleepers. A rail is placed at each step position of the double-block sleepers to assemble the rails as wheel guard rails. The number of rails in the wheel guard rails is the same as that of the double-block rails.

[0129] Draw the sleeper spacing line on the rail, square the sleepers accurately, install spring bars, tighten spike bolts to connect the rails to the sleepers; install screw adjusters between the first and second sleepers at the rail end and every 4 to 5 sleepers for the remaining sleepers, use fish plates to connect adjacent tool rails firmly, and control the rail gap to about 20mm;

[0130] n. Rough adjustment of double-block track arrangement:

[0131] According to the measurement data of the base mark point, the track is roughly adjusted. The L ruler and the track gauge ruler are used to raise the track to about 5mm below the elevation value, and the direction of the track is adjusted. After the direction is adjusted in place, the elevation is adjusted, the track gauge is checked, and the track gauge support rod and lateral support rod are installed. After the track adjustment is completed, the track error is controlled within: direction ±2mm, elevation 0~-2mm, track gauge ±1mm, and the change rate is 1 / 1000;

[0132] o. Tie up the upper reinforcement of the track bed:

[0133] Transfer the upper steel bars of the roadbed to the construction location, arrange the upper steel bars of the roadbed slab according to the design requirements, and use insulating cards or insulating straps to firmly tie the steel bars at the intersection of the longitudinal and transverse steel bars. The roughly adjusted double-block rails must not be disturbed during the steel bar tying process. After the steel bars are tied, weld the grounding steel bars and grounding terminals. Take protective measures during welding to avoid burns and damage to the geotextile; after the upper steel bars are tied, promptly place the reinforced concrete pads of the bottom of the roadbed. The number of pads is ≮㎡ / 4 (≮ means "≥");

[0134] p. Spreading wheel guard sleepers:

[0135] After the rough adjustment of the double-block rail and the tying of the upper steel bars of the ballast are completed, the wheel guard sleepers are transported by a small flat car and spread to the center line of the line between the double-block sleepers. Pay attention to whether there is a position conflict between the steel bars at the bottom of the wheel guard sleepers and the steel bars at the upper layer of the ballast. Otherwise, the position of the steel bars at the upper layer of the ballast should be adjusted to avoid damage to the insulating steel bars of the wheel guard sleepers.

[0136] q. Assembly of wheel guard rails:

[0137] Place the wheel guard rail sleeper bottom pad, use a manual gantry crane to place the rails placed on the double-block rail sleeper platform onto the wheel guard rail sleeper, install bolts, washers and other fasteners and tighten them preliminarily with a T-wrench, connect adjacent rails with fishplates, and install screw adjusters at both ends of each unit plate;

[0138] r. Rough adjustment of guard rail:

[0139] The geometrical dimension control accuracy of the wheel guard rail is lower than that of the double-block rail. The wheel guard rail is roughly adjusted based on the reference stock of the double-block rail. The adjustment sequence is direction first and then elevation.

[0140] Elevation: Use the screw adjusters at both ends of the unit plate to adjust the direction and elevation of the rail. Use a tape measure and a square ruler to check the direction and elevation of the guard rail. The adjustment error should be controlled within ±10mm.

[0141] s. Installation and adjustment of track bed template:

[0142] Select matching ballast plate templates according to different ballast plate lengths. The installation order is longitudinal template first and then transverse template. The bottom of the template is firmly supported by square wood to prevent the template from hanging in the air. Check the plate size and verticality and make timely adjustments. The spacing between adjacent ballast plates and the ballast plates on both sides of the expansion joints must meet the requirements.

[0143] t. Double-block track arrangement fine-tuning for the first time:

[0144] The double-block track is fine-tuned through the CPⅢ track control network using a total station and a track fine-tuning trolley. The direction, superelevation and elevation are adjusted by adjusting the screw adjuster and the lateral support rod. After the fine-tuning is completed, the adjustment error is controlled within: direction ±1mm, elevation 0~-0.5mm, track gauge ±0.5mm, and the change rate is 1 / 1000.

[0145] u. Steps for adjusting the size of the guard rail:

[0146] After the first fine adjustment of the double-block rail is completed, the wheel guard rail size is adjusted immediately. The adjustment steps are also based on the double-block rail reference stock, first the direction and then the elevation, and the adjustment error is controlled within ±5mm. After the adjustment is completed, a 530mm square timber is used between the wheel guard rail and the mainline rail, and a 400mm square timber is used between the two wheel guard rails. The square timber is placed at the waist of the rail. After the placement is completed, the double-block rail and the wheel guard rail form an integral structure.

[0147] v. Double-block track arrangement fine-tuning for the second time:

[0148] The second fine adjustment of the double-block track is carried out after the wheel guard track size adjustment is completed to ensure that the track geometry meets the requirements. The fine adjustment method is the same as the first fine adjustment. After the fine adjustment is completed, the adjustment error is controlled within: direction ±1mm, elevation 0~-0.5mm, track gauge ±0.5mm, and the change rate is 1 / 1000; the track bed concrete pouring should be completed within 12 hours after the fine adjustment is completed;

[0149] w. Check the size of the wheel guard rail:

[0150] After the second fine adjustment of the double-block rail is completed, the geometric dimensions of the guard rail are promptly reviewed and checked. The inspection is completed quickly using a self-made inspection tool, and the positions that do not meet the requirements are adjusted in time. The dimension review of the guard rail should not disturb the rail, and the dimension inspection and review requirements should be completed quickly to leave sufficient time for the concrete pouring of the ballast bed;

[0151] x. Roadbed concrete pouring:

[0152] Before pouring the ballast bed, the surfaces of the double-block sleepers, wheel guard sleepers and geotextiles should be fully moistened and free of water accumulation. When the concrete is transported to the site, it should be pumped into the vehicle-mounted pump by a sky pump and then transported to the pouring point by the vehicle-mounted pump. The pouring method should be from far to near, and the pouring should be done while removing the pipes. During the pouring process, attention should be paid to the vibration of the concrete under the double-block sleepers and wheel guard sleepers to ensure that the concrete under the sleepers is dense. The finishing of the concrete should focus on the control of the concrete elevation of the bottom of the rail, around the sleepers and adjacent slabs to ensure the finishing quality.

[0153] y. Stress relief and concrete curing:

[0154] After the initial setting of the ballast concrete, the fishplate and bolts shall be removed in time to avoid the stress transfer of the rails; according to the test determination method, after the concrete reaches the specified strength, the fasteners shall be loosened in time, and the loosening of the fasteners shall be carried out by jump release to release the stress of the rails in time; before the final setting of the concrete, the screw adjuster shall be loosened by 1 / 2 turn;

[0155] The final finishing should be completed before the final setting of the concrete. After completion, the concrete curing agent should be applied in time and watering should be carried out in time. The curing time of the roadbed concrete should not be less than 14 days.

[0156] z. Data collection:

[0157] On the second day after the concrete pouring is completed, the track geometry data should be collected in time using a fine-tuning trolley in conjunction with a total station. This can timely analyze the track geometry and provide a basis for subsequent process improvements and line fine-tuning. It is strictly forbidden to remove the tool rail before data collection.

[0158] The beneficial effects of the present invention are:

[0159] The invention can be used to master the wheel guard rail type ballastless track bed construction technology, which has high construction efficiency, controllable quality, low safety risk, low cost, strong operability, and can be widely promoted and applied.

[0160] In short, if Figure 1 As shown, the overall process of the present invention is as follows: construction preparation → measurement and setting out and benchmark survey and setting → beam surface roughening and cleaning → sleeve connection steel bar installation → base steel bar binding → bridge expansion joint embedded parts installation → base and groove template installation → base concrete pouring and maintenance → laying isolation layer geotextile and elastic pad → installation of groove insulation steel bar skeleton → roadbed bottom steel bar binding → scattering double-block sleepers → tool rail transportation and double-block track assembly → double-block track rough adjustment → roadbed upper steel bar binding → scattering wheel guard sleepers → wheel guard rail assembly → wheel guard rail size rough adjustment → roadbed template installation and adjustment → double-block rail fine adjustment first time → wheel guard rail size adjustment → double-block rail fine adjustment second time → wheel guard rail size verification → roadbed concrete pouring → stress release and concrete maintenance → data collection. The wheel guard rail type ballastless roadbed construction technology of the present invention has high construction efficiency, controllable quality, low safety risk, low cost, strong operability, and can be widely promoted and applied.

[0161] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for constructing a wheel guard rail type ballastless track bed, characterized in that: include: Construction preparation steps, surveying and setting out steps, beam surface chiseling and cleaning steps, sleeve connection steel bar installation steps, base steel bar tying steps, bridge expansion joint embedded parts installation steps, base and groove template installation steps, base concrete pouring and maintenance steps, laying isolation layer geotextile and elastic pad steps, installing groove insulation steel bar skeleton steps, ballast bottom steel bar tying steps, spreading double-block sleepers steps, tool rail transportation and double-block track assembly steps, double-block track lifting rough adjustment steps, ballast upper steel bar tying steps, spreading wheel guard sleepers steps, wheel guard track assembly steps, wheel guard track size rough adjustment steps, ballast template installation and adjustment steps, double-block track first fine adjustment steps, wheel guard track size adjustment steps, double-block track second fine adjustment steps, wheel guard track size verification steps, ballast concrete pouring steps, stress relief and concrete maintenance steps, data collection steps; Among them, the steps of spreading wheel guard sleepers are: After the rough adjustment of the double-block rail and the tying of the upper steel bars of the ballast are completed, the wheel guard sleepers are transported by a small flat car and spread to the center line of the line between the double-block sleepers. Pay attention to whether there is a position conflict between the steel bars at the bottom of the wheel guard sleepers and the steel bars at the upper layer of the ballast. Otherwise, the position of the steel bars at the upper layer of the ballast should be adjusted to avoid damage to the insulating steel bars of the wheel guard sleepers. Assembly steps of wheel guard rail: Place the wheel guard rail sleeper bottom pad, use a manual gantry crane to place the rails placed on the double-block rail sleeper platform onto the wheel guard rail sleeper, install bolts, washers and other fasteners and tighten them preliminarily with a T-wrench, connect adjacent rails with fishplates, and install screw adjusters at both ends of each unit plate; Steps for rough adjustment of guard rail: The geometrical dimension control accuracy of the wheel guard rail is lower than that of the double-block rail. The wheel guard rail is roughly adjusted based on the reference stock of the double-block rail. The adjustment sequence is direction first and then elevation. Elevation: Use the screw adjusters at both ends of the unit plate to adjust the direction and elevation of the rail. Use a tape measure and a square ruler to check the direction and elevation of the guard rail. The adjustment error should be controlled within ±10mm. Steps for adjusting the size of the guard rail: After the first fine adjustment of the double-block rail is completed, the wheel guard rail size is adjusted immediately. The adjustment steps are also based on the double-block rail reference stock, first the direction and then the elevation, and the adjustment error is controlled within ±5mm. After the adjustment is completed, a 530mm square timber is used between the wheel guard rail and the mainline rail, and a 400mm square timber is used between the two wheel guard rails. The square timber is placed at the waist of the rail. After the placement is completed, the double-block rail and the wheel guard rail form an integral structure. Steps for checking the size of the guard rail: After the second fine-tuning of the double-block track is completed, the geometric dimensions of the wheel guard rail are promptly reviewed and checked. The inspection is completed quickly using a self-made inspection tool, and the positions that do not meet the requirements are adjusted in time. The wheel guard rail dimension review should not disturb the track, and the dimension inspection and review requirements must be completed quickly to leave sufficient time for the pouring of the ballast bed concrete.

2. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the construction preparation steps: The construction preparation of the wheel guard rail type ballastless track is also a systematic and complex project, which requires comprehensive consideration of the construction environment, the selection of construction schemes, the logistics and transportation issues of the entire construction process, the bridge elevation review, the construction sequence of each process and the pouring method, and preparations must be made in advance; Selection of construction scheme: The project is located above an existing busy high-speed railway, and the line is a single-track railway. The operation management unit requires that large equipment be avoided as much as possible to avoid safety impacts on the operating line; At present, the construction of double-block ballastless track mainly adopts the frame method and the tool rail method. The frame method occupies the space between the double-block sleepers, which makes it impossible to assemble the wheel guard rail. Therefore, the tool rail method is selected as its construction method. Logistics transportation method: Ballastless track logistics transportation is divided into internal logistics transportation and external logistics transportation; Internal logistics transportation refers to the transportation of materials, equipment and tools within the construction section. The order of transfer of materials and tools should be organized and planned according to the needs of the construction section ahead; External logistics transportation refers to the transportation from the outside of the construction section to the construction section. All materials, equipment and tools should be carefully planned and organized according to the overall construction process, especially the construction organization of the first section. Because it is a single-line construction, materials, equipment and tools cannot be piled up too much on site, and can only be carried out step by step according to the construction process requirements. Excessive stacking and premature transportation will directly affect the construction progress on site; The entire logistics and transportation guarantee is the key to the progress control of ballastless track construction. The early construction preparation work is arduous, and careful planning and preparation are required to ensure the flow of construction technology and progress requirements; Choice of concrete pouring method: To be precise, it is also a link in logistics transportation. According to the site conditions, this project adopts a sky pump outside the influence range of the existing line to pump it to the vehicle-mounted pump above the bridge, and then transports it to the construction site by the vehicle-mounted pump. The pouring method is to dismantle the pipe from the far end to the near end. Before the construction of the ballastless track bed project, the bridge elevation shall be reviewed according to the CPⅢ result control points, and the cutting size of the base steel bars shall be based on the actual bridge elevation; the template selection shall be based on the actual elevation.

3. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the steps of surveying, setting out and benchmarking: After the work surface is handed over, the positions of each base plate and the center line of the line are marked according to the CPⅢ measurement control network, and the base point is measured on the outside of the base plate, and a base mark is set every 5m and buried firmly; The invention is characterized in that it comprises the steps of roughening and cleaning the beam surface: Pop up the base edge line according to the position of the released base plate, and chisel and clean the beam surface within the range of the base plate. The chiseling depth should be ≥2mm, and the newly exposed concrete area should not be less than 75%. When chiseling, check the number of reserved sleeves on the beam surface and mark the missing or damaged ones on site; The invention is characterized in that it comprises the following steps of installing the sleeve-connected steel bars: Remove the sleeve cap on the beam surface, clean up the debris in the sleeve, screw the processed L-shaped connecting steel bar into the sleeve, and tighten it with a torque wrench according to the designed torque value. For damaged or missing embedded sleeves, drill holes on both sides of the sleeve setting position, and implant the L-shaped steel bars for embedding, with the implantation depth meeting the requirements.

4. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the steps of base reinforcement tying: According to the design drawings, use ink lines to pop out all the longitudinal and transverse steel bar position lines and the base groove position lines. The steel bars are placed and tied according to the popped-out steel bar line positions. After the lower steel bars are tied, the concrete pads are placed at ≮㎡ / 4. After completion, the upper steel bars are tied. It includes the installation steps of embedded parts of bridge expansion joints: After the base reinforcement is tied, straighten the embedded gate-shaped reinforcement at the beam end, install and tie the expansion joint reinforcement at the beam end, and install the expansion joint steel at the beam end simultaneously. After the expansion joint steel on both sides of the beam end is installed, check whether the beam joint width meets the design requirements and whether the steel is firmly fixed; It includes the steps for installing the base and groove template: Install the base template according to the base edge line. Each plate should be equipped with a corresponding template. The templates are firmly connected with bolts. The installation order is longitudinal template first and then transverse template. The concrete elevation control points are affixed on the template according to the measurement data of each plate. The groove template is assembled first. The groove template is mainly composed of a cross stretcher and a groove template. The cross stretcher and the groove template are connected as a whole by 4 16mm diameter screw rods. When assembling, pay attention to the matching use of the longitudinal and transverse groove templates and cross stretchers. Lift the assembled groove template to the groove installation position, align it according to the groove position line marked on the beam surface, determine the horizontal position of the groove template, use a U-shaped card to fix the cross stretcher on the base template, and use the concrete elevation control point on the base template to adjust it into place by pulling the wire with the screw rod on the groove template; It includes the steps of pouring and curing the concrete base: The concrete is transported to the construction site and poured by a combination of a sky pump and a vehicle-mounted pump. During the pouring process, the two should cooperate well with each other and be directed by the same person. The concrete pouring should be done from the bottom to the top longitudinally and from the inside to the outside of the curve horizontally. Do not collide with the groove template during the pouring process. The concrete elevation is based on the control point on the template. It is done manually or with a finishing machine. After the finishing is completed, the elevation dimensions should be installed to check and confirm the base elevation. The elevations of the two adjacent base plates should be checked one by one to ensure that the base elevation is controlled within ±10mm and the flatness is 3mm / m. After the concrete has finally set, apply concrete curing agent. The curing agent should be applied evenly and water should be sprinkled in time to ensure that the concrete is fully cured. The curing days should be no less than 7 days.

5. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the steps of laying isolation layer geotextile and elastic pad: Clean the base and groove, check the flatness and size, and lay the isolation layer geotextile after meeting the requirements. The geotextile should be laid flat, without wrinkles or damage. It is strictly forbidden to overlap the geotextile on the same board. Use tape to fix the geotextile on the base around the base; draw the groove edge line according to the groove position, cut it, and put the geotextile at the groove position into the groove. Elastic pads are laid around the grooves and sealed and fixed with tape and geotextile; It includes the steps of installing the grooved insulated steel reinforcement frame: Tie the processed grooved insulated steel bars to the grooved steel bars to form a steel bar skeleton, place the tied grooved insulated steel bar skeleton in the groove, and place concrete pads at the bottom of the skeleton. The number of pads is ≮㎡ / 4; It includes the following steps for tying the reinforcement bars of the ballast bottom layer: Mark the positions of the longitudinal and transverse ballast steel bars on the geotextile, place the processed semi-finished ballast steel bars neatly according to the marked positions, and use insulating cards or insulating ties to tie and fix the longitudinal and transverse steel bar nodes. During the tying process, it is strictly forbidden for the steel bars to damage or move the geotextile.

6. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the following steps to spread the double block sleepers: The double-block sleepers are hoisted onto the bridge and are manually lifted to the installation position on the bottom steel bar of the ballast bed. The double-block sleepers are preliminarily squared according to the centerline of the ballast bed. After completion, the elastic pads, half-point posts, blocks, spikes and springs of the double-block sleepers are installed. The springs should be placed at the block position and should not occupy the rail installation position. Including tool rail transportation and double-block rail assembly steps: The tool rail is transported to the installation location by two self-made simple transport gantries. After the steel rail is transported to the location, the double-block sleeper is squared, and two steel rails are placed in the grooves on the double-block sleeper. A steel rail is placed at each step position of the double-block sleeper to assemble the rails as the wheel guard rail row. The number of steel rails in the wheel guard rail row is the same as that of the double-block rail row. Draw the sleeper spacing line on the rail, square the sleepers accurately, install spring bars, tighten spike bolts to connect the rails to the sleepers; install screw adjusters between the first and second sleepers at the rail end and every 4 to 5 sleepers for the remaining sleepers, use fish plates to connect adjacent tool rails firmly, and control the rail gap to about 20mm; It includes the steps of rough adjustment of double-block track arrangement: The track is roughly adjusted according to the measurement data of the base mark points. The L ruler and the track gauge are used to raise the track to about 5mm below the elevation value, and the direction of the track is adjusted. After the direction is adjusted in place, the elevation is adjusted, the track gauge is verified, and the gauge support rods and lateral support rods are installed. After the track adjustment is completed, the track error is controlled within: direction ±2mm, elevation 0~-2mm, gauge ±1mm, and the change rate is 1 / 1000.

7. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the following steps for tying the upper reinforcement bars of the ballast: Transfer the upper steel bars of the track bed to the construction location, arrange the upper steel bars of the track bed according to the design requirements, and use insulating cards or insulating straps to firmly tie the steel bars at the intersection of the longitudinal and transverse steel bars. The roughly adjusted double-block rails must not be disturbed during the steel bar tying process. After the steel bars are tied, weld the grounding steel bars and grounding terminals. Take protective measures during welding to avoid burns and damage to the geotextile; after the upper steel bars are tied, promptly place the reinforced concrete pads of the track bed bottom layer, and the number of pads is ≮㎡ / 4; It includes the steps of trackbed formwork installation and adjustment: Select matching ballast plate templates according to different ballast plate lengths. The installation order is longitudinal template first and then transverse template. The bottom of the template is firmly supported by square wood to prevent the template from hanging in the air. Check the plate size and verticality and make timely adjustments. The spacing between adjacent ballast plates and the ballast plates on both sides of the expansion joints must meet the requirements.

8. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the first pass of double-block track adjustment: The double-block track is fine-tuned through the CPⅢ track control network using a total station and a track fine-tuning trolley. The direction, superelevation and elevation are adjusted by adjusting the screw adjuster and the lateral support rod. After the fine-tuning is completed, the adjustment error is controlled within: direction ±1mm, elevation 0~-0.5mm, track gauge ±0.5mm, and the change rate is 1 / 1000. It includes the second pass of double-block track adjustment: The second fine-tuning of the double-block track is carried out after the size adjustment of the guard rail is completed to ensure that the geometric state of the track meets the requirements. The fine-tuning method is the same as the first fine-tuning. After the fine-tuning is completed, the adjustment error is controlled within: direction ±1mm, elevation 0~-0.5mm, track gauge ±0.5mm, and the change rate is 1 / 1000; after the fine-tuning is completed, the ballast bed concrete pouring should be completed within 12 hours.

9. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the following steps of track bed concrete pouring: Before pouring the ballast bed, the surfaces of the double-block sleepers, wheel guard sleepers and geotextiles should be fully moistened and free of water accumulation. When the concrete is transported to the site, it should be pumped into the vehicle-mounted pump by a sky pump and then transported to the pouring point by the vehicle-mounted pump. The pouring method should be from far to near, and the pouring should be done while removing the pipes. During the pouring process, attention should be paid to the vibration of the concrete under the double-block sleepers and wheel guard sleepers to ensure that the concrete under the sleepers is dense. The finishing of the concrete should focus on the control of the concrete elevation of the bottom of the rail, around the sleepers and adjacent slabs to ensure the finishing quality. It includes stress relief and concrete curing steps: After the initial setting of the ballast concrete, the fishplate and bolts shall be removed in time to avoid the stress transfer of the rails; according to the test determination method, after the concrete reaches the specified strength, the fasteners shall be loosened in time, and the loosening of the fasteners shall be carried out by jump release to release the stress of the rails in time; before the final setting of the concrete, the screw adjuster shall be loosened by 1 / 2 turn; The final finishing should be completed before the final setting of the concrete. After completion, the concrete curing agent should be applied in time and watering should be carried out in time. The curing time of the roadbed concrete should not be less than 14 days.

10. The method for constructing a wheel guard rail type ballastless track bed according to claim 1, characterized in that: It includes the steps of data collection: on the second day after the concrete pouring is completed, the track geometry data should be collected in time for the poured roadbed using a fine-tuning trolley in conjunction with a total station. This can timely analyze the track geometry and provide a basis for subsequent process improvements and line fine-tuning. It is strictly forbidden to remove the tool rail before data collection.

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