A method for repairing and constructing a prefabricated elastic solidified track bed

Abstract

An assembled elastic curing track bed replacement method comprises a preparation stage, a replacement stage and a recovery stage: the preparation stage. Construction datum is established through data measurement, a special gantry crane temporary track is laid, crack resistance of a support pier is strengthened, a rail cut joint is used to release temperature stress, and high-precision and high-stability operation conditions are provided for subsequent construction; the replacement stage: a transverse rail shifting is used in cooperation with a low-resistance slide, an indirect fine adjustment technology between new sleepers and a dynamic mortar pouring process are used, efficient replacement of sleepers and non-destructive repair of track bed structure are realized; the recovery stage: high-frequency tamping is used to optimize ballast compactness, narrow-gap welding is used to reduce a heat affected zone, and line fine adjustment based on BIM is used to recover track smoothness and structural integrity. The assembled elastic curing track bed replacement method realizes efficient replacement of the assembled elastic curing track bed, maximally improves construction efficiency and reduces damage to the rail, has high creativity and practicality, and is suitable for maintenance and replacement work of various railway tracks.

Description

TECHNICAL FIELD

[0001] The application relates to a construction method, in particular to a prefabricated elastic solidified track bed maintenance construction method. BACKGROUND

[0002] The traditional method adopts fixed-length rail cutting, which leads to a long construction window period and is prone to rail thermal expansion and cold contraction problems due to the lack of temperature stress calculation; the temporary track pier of the gantry crane is mostly made of ordinary concrete, which has a long solidification time and poor crack resistance, thereby affecting the construction progress. The rail sleeper fine adjustment relies on manual experience and lacks coordinated control with the solidified track ballast and mortar bag, which is prone to track linear deviation. SUMMARY

[0003] In order to solve the defects in the prior art, the application discloses a prefabricated elastic solidified track bed maintenance construction method, and the technical scheme is as follows:

[0004] A prefabricated elastic solidified track bed replacement method, characterized by comprising a preparation stage, a replacement stage and a recovery stage:

[0005] The preparation stage: through data measurement, a construction reference is established, a gantry crane temporary track is laid, the crack resistance of the pier is strengthened, the temperature stress of the rail cutting joint is released, and high-precision and high-stability operation conditions are provided for subsequent construction;

[0006] The replacement stage: the transverse rail shifting is cooperated with the low-resistance design of the slide, the indirect fine adjustment technology of the new rail sleeper and the dynamic mortar pouring process, so that the efficient replacement of the rail sleeper and the non-destructive repair of the track bed structure are realized;

[0007] The recovery stage: through the high-frequency tamping optimization of the track ballast compactness, the narrow-gap welding reduction of the heat-affected zone and the line fine adjustment based on BIM, the track smoothness and structural integrity are recovered.

[0008] Preferably, the preparation stage comprises data measurement, laying of a gantry crane temporary track, removal of track ballast on both sides and between sleepers, and rail cutting joint, wherein:

[0009] Data measurement: three-dimensional modeling of the track line is performed by combining a total station and a laser scanner;

[0010] Laying of the gantry crane temporary track: a stable support platform is provided for the gantry crane to ensure track smoothness and prevent local settlement, including (1) pier design: the longitudinal distance between the piers, i.e. the distance of the non-removed section and the distance of the removed section, is determined; the bending bearing capacity of the pier size is verified by finite element simulation;

[0011] (2) material and structure: fast-hardening polymer concrete; glass fiber cloth is laid at intervals, and the tensile strength is greater than or equal to 100 MPa, thereby improving the crack resistance of the pier;

[0012] (3) Installation process: non-woven fabric isolation layer is laid on the inner side of the template; channel steel is fixed with the support pier through expansion screws, and the lap joint is seamless.

[0013] The two sides and the inter-pillar ballast are removed: the working surface is cleaned to the invert backfill layer to provide an unobstructed construction space for the replacement of the sleeper, including (1) layered removal of unhardened ballast to the depth of the invert surface; (2) removal of ballast protection temporary storage: evenly spread on the adjacent track or stored in bags in the comprehensive cavern.

[0014] The rail cut joint: releases the rail temperature stress, avoids track deformation due to thermal expansion and contraction during construction, including: (1) limiting the cut joint length, which is determined according to the calculation of the rail temperature stress formula; (2) when ΔT≤20℃, the expansion amount ΔL, the gap between the clamps is designed to completely absorb the expansion amount; (3) using clamps to connect the cut joint rails, disassembling the clamps daily to cooperate with the rail shifting operation, and restoring seamless after construction.

[0015] Preferably, the replacement stage includes the following steps:

[0016] 1) Remove the fasteners

[0017] Remove the fasteners in the rail shifting section. For seamless rails, the length of the removed fasteners should be determined according to the difference between the working temperature and the locked rail temperature;

[0018] 2) Transverse rail shifting

[0019] Install the transverse rail shifting equipment, including the rail shifting tool, the rail slide, and the anti-slip device. The rail shifting tool is used for large super-elevation sections of seamless and jointed rails; the rail slide is used for all rail shifting sections; the anti-slip device is used for jointed rail sections with large longitudinal slopes;

[0020] 3) Assemble the gantry crane

[0021] Remove the fasteners, assemble and debug the gantry crane, and unload the new sleepers from the rail car simultaneously;

[0022] 4) Unload the new sleepers

[0023] After the gantry crane is assembled and debugged, use the gantry crane to unload the new sleepers from the rail car and transport them longitudinally to the replacement sleeper position for temporary storage;

[0024] 5) Remove the old sleepers

[0025] Use the gantry crane to lift, transport, and load the old sleepers onto the rail car; after the old sleepers are loaded, remove the gantry crane and load it onto the car;

[0026] 6) Return the rail and install the fasteners

[0027] Use the rail shifting tool or manpower to return and reset the rail, and install the fasteners, including the fasteners for the newly replaced sleepers.

[0028] 7) Fine-tuning of new sleepers

[0029] After the new sleeper is hung on the rail using fasteners, the position of the new sleeper is indirectly adjusted by adjusting the position of the rail using a screw rod.

[0030] 8) Mortar bag injection

[0031] A mortar injection bag is laid under the solidified ballast of the sleepers, and a new filling layer of mortar is injected.

[0032] Preferred option: 1) Restoration of ballast on both sides and between the pillows

[0033] Using subsequent skylights, the ballast on both sides of the line and between the sleepers will be backfilled and tamped.

[0034] 2) Dismantle the temporary track of the gantry.

[0035] Remove the temporary tracks and temporary supports of the gantry crane and restore the appearance of the ballast.

[0036] 3) Rail welding

[0037] For rails that have already been cut in sections requiring concentrated replacement, rail welding should be carried out, and longer rails should be replaced as needed.

[0038] 4) Line fine-tuning

[0039] After all sleepers have been replaced, the track in the construction section will be fine-tuned or the track will be moved to restore the smoothness of the line, and the speed will be gradually increased in the construction area.

[0040] Preferably, the transverse guide rail includes: a guide rail distance of 800~850mm, and a hydraulic jacking device (thrust ≥10T) is used to move the rail; the surface of the rail slide is coated with polytetrafluoroethylene coating, with a friction coefficient ≤0.1, reducing the guide rail resistance by 30%.

[0041] Preferably, the new sleeper fine-tuning adopts a two-way screw to indirectly adjust the rail position with a screw pitch accuracy of ±0.02mm, and monitors the gap value between adjacent mortar bags with a laser displacement sensor to ensure that the sleeper positioning accuracy is ±0.5mm.

[0042] Preferably, the mortar bag filling is dynamically selected according to the sleeper spacing, using a single sleeper or two sleepers, and employing fluid mortar with a slump of 180±20mm and a filling density of ≥95%.

[0043] Preferably, the rail welding adopts narrow gap flash welding: for 50m short rails after cutting, the welding heat-affected zone is ≤20mm.

[0044] Preferably, the line fine adjustment is a dynamic adjustment based on BIM: importing the track alignment data before and after construction into the BIM model to generate a fine adjustment vector diagram to guide the 0.1mm-level precision adjustment of the track breaker, and finally the track smoothness (TQI index) is less than or equal to 2.0.

[0045] The application also discloses a railway track maintenance method, which is realized by using the above-mentioned assembly type elastic solidified ballast bed replacement method when the old sleepers and solidified ballast are replaced by new sleepers and solidified ballast after the track is broken. Beneficial effects

[0046] The assembly type elastic solidified ballast bed replacement is realized, the construction efficiency is maximally improved, and the damage to the steel rail is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The application also discloses a railway track maintenance method, which is realized by using the above-mentioned assembly type elastic solidified ballast bed replacement method when the old sleepers and solidified ballast are replaced by new sleepers and solidified ballast after the track is broken. DETAILED DESCRIPTION

[0048] An assembly type elastic solidified ballast bed replacement method, characterized in that the method comprises a preparation stage, a replacement stage and a recovery stage.

[0049] The preparation stage: the construction datum is established through data measurement, the gantry crane temporary track is laid, the anti-cracking property of the support pier is strengthened, the temperature stress of the steel rail cut joint is released, and high-precision and high-stability operation conditions are provided for subsequent construction.

[0050] The preparation stage comprises data measurement, laying of the gantry crane temporary track, removal of the ballast on both sides and between sleepers, and steel rail cut joint.

[0051] Data measurement: a total station and a laser scanner are combined to perform three-dimensional modeling on the track alignment, digital construction datum is generated by combining the fastener adjustment amount (monitored dynamically by a torque sensor) and the ballast thickness (ultrasonic thickness gauge) data. The traditional method relies on manual measurement, and has large error and long time consumption. The application improves the precision to ±0.5mm through digital modeling, and provides a high-precision datum for subsequent fine adjustment.

[0052] Laying of the gantry crane temporary track: a stable support platform is provided for the gantry crane, the track smoothness is ensured, and local settlement is prevented. The temporary support pier design: the longitudinal spacing of the temporary support pier is 6m (non-removal area) and 3m (removal area): based on the track load distribution and support pier bearing capacity calculation, the support pier spacing is encrypted to 3m when the local load in the removal section is increased, and the track settlement is prevented.

[0053] The support pier size is 400mm*500mm*≥100mm: the bending moment bearing demand of the gantry crane walking channel steel (channel steel specification is 18#) is verified through finite element simulation;

[0054] (2) Material and structure: fast-hardening polymer concrete: add early strength agent (such as sulphoaluminate cement) and polymer fiber, so that the strength of the pier reaches 20 MPa within 12 hours, and the construction period is shortened; glass fiber cloth is laid at intervals: one layer of glass fiber cloth (tensile strength ≥ 100 MPa) is laid every 100 mm of height, which significantly improves the anti-cracking performance of the pier and avoids the expansion of cracks in traditional concrete piers due to vibration. The traditional pier needs to be cured for more than 24 hours and is prone to cracking. Through material and structure optimization, the construction time of the pier is shortened by 50%, and the anti-cracking performance is improved by 3 times.

[0055] (3) Installation process: lay a non-woven fabric isolation layer on the inside of the formwork; the channel steel is fixed to the pier by expansion screws, and the lap joint is seamless.

[0056] The two sides and the sleeper interval ballast are removed: the working surface is cleaned to the invert backfill layer, providing an obstacle-free construction space for sleeper replacement, including (1) layered removal of unhardened ballast, depth to the surface of the invert; (2) removal of ballast for temporary storage: evenly spread on adjacent tracks or stored in a comprehensive cavern.

[0057] The steel rail cut joint: releases the thermal stress of the steel rail, avoiding deformation of the track due to thermal expansion and contraction during construction, including: (1) limiting the length of the cut joint, determined according to the steel rail thermal stress formula; (2) when ΔT ≤ 20℃, the expansion amount ΔL, matching the gap design of the clamping plate, completely absorbing the expansion amount; (3) using a clamping plate to connect the cut joint steel rail, daily disassembly and assembly of the clamping plate to cooperate with the rail shifting operation, and restoring seamless after construction. The traditional cut joint length is arbitrary, which easily leads to rail stress exceeding the limit. The present invention limits the length of the cut joint through theoretical calculation, combined with dynamic adjustment of the clamping plate gap, to eliminate the influence of thermal stress on track smoothness.

[0058] Replacement stage: using transverse rail shifting, slide low resistance design, new rail sleeper interval indirect fine adjustment technology and dynamic mortar pouring process, realizing efficient replacement of sleepers and non-destructive repair of track bed structure;

[0059] The replacement stage includes the following steps:

[0060] 1) Remove the fasteners

[0061] Remove the fasteners in the rail shifting section. For seamless steel rails, the length of the fasteners to be removed should be determined according to the difference between the operating temperature and the locking rail temperature;

[0062] 2) Transverse rail shifting

[0063] Install transverse rail shifting equipment, including rail shifting tooling, steel rail slide and anti-slip device. The rail shifting tooling is used for large super-high sections of seamless steel rails and jointed steel rails; the steel rail slide is used for all rail shifting sections; the anti-slip device is used for jointed steel rail sections with large longitudinal slopes;

[0064] The rail pushing distance is 800-850 mm: according to the sleeper width (the standard sleeper width is 300 mm) and the operation space requirement, through simulation verification, 800 mm is the minimum safety distance (to avoid colliding with the edge of the sleeper), and 850 mm is the maximum economic distance (to reduce the length of the rail slide).

[0065] The rail pushing tool is cooperatively designed with the slide:

[0066] The rail pushing tool adopts a hydraulic pushing device (the pushing force is greater than or equal to 10 T), and is suitable for pushing the seamless rail in a large super-high section (the curve radius is less than or equal to 800 m).

[0067] The surface of the rail slide is coated with a polytetrafluoroethylene coating (the friction coefficient is less than or equal to 0.1), and the rail pushing resistance is reduced by 30%.

[0068] The traditional rail pushing relies on manpower or a single machine, and the efficiency is low and the fasteners are easily damaged. Through cooperative design of the equipment and parameter optimization, the rail pushing efficiency is improved by 2 times, and the rail resetting accuracy is ±1 mm.

[0069] 3) Assemble the gantry crane

[0070] The fasteners are removed, the rail is pushed, the gantry crane is assembled and debugged, and the new sleeper is unloaded at the same time;

[0071] 4) Unload the new sleeper

[0072] After the gantry crane is assembled and debugged, the new sleeper is unloaded from the rail flat car by the gantry crane and longitudinally transported to the replacement sleeper position for temporary storage;

[0073] 5) Remove the old sleeper

[0074] The old sleeper is lifted, transported and loaded onto the rail flat car by the gantry crane; after the old sleeper is loaded, the gantry crane is removed and loaded;

[0075] 6) Push the rail back and install the fasteners

[0076] The rail is pushed back by the rail pushing tool or manpower, and the fasteners are installed, including the fasteners of the new replacement sleeper.

[0077] 7) Fine adjustment of the new sleeper

[0078] After the new sleeper is hung on the rail by the fasteners, the position of the new sleeper is indirectly adjusted by adjusting the position of the rail through the screw rod; the bidirectional screw rod (the pitch is 5 mm, and the accuracy is ±0.02 mm) is used to adjust the transverse position of the rail, and the displacement of the sleeper is indirectly controlled through the rigid connection between the rail and the sleeper fastener. During the adjustment, the gap value of the adjacent mortar bag is monitored in real time (monitored by a laser displacement sensor, and the threshold value is less than or equal to 0.3 mm), so that the existing solidified layer is not damaged during the fine adjustment process.

[0079] Traditional fine adjustment directly moves the rail sleeper, which easily disturbs the ballast layer. The application indirectly adjusts through the rail, the precision is improved to ±0.5mm, and the mortar bag is avoided from being separated from the joint.

[0080] 8) Mortar bag filling

[0081] The mortar filling bag is laid under the sleeper solidified ballast, and the filling layer mortar is refilled.

[0082] Flexible adjustment of longitudinal length: According to the sleeper spacing (standard 600mm), the single sleeper (600mm) or double sleeper (1200mm) filling is dynamically selected to replace the original design of 3m fixed length. Through the matching of fluidity mortar (slump 180±20mm) and tensile strength of the bag body (≥5kN / m), the filling density is ensured to be ≥95%.

[0083] Traditional fixed length filling is easy to cause material waste or filling not dense. The application dynamically adjusts, the material utilization rate is improved by 20%, and the dense rate is improved to 98%.

[0084] Restoration stage: Through high-frequency tamping to optimize the ballast density, narrow gap welding to reduce the heat affected zone, and BIM-based line fine adjustment, the track smoothness and structural integrity are restored.

[0085] Ballast tamping: high-frequency pneumatic tamping machine: adopt tamping head with vibration frequency 40Hz and exciting force 5kN, combined with ballast grading optimization (particle size 10~30mm accounts for ≥70%), so that the transverse resistance of the ballast bed is improved to 12kN / sleeper (traditional method is 8kN / sleeper).

[0086] Rail welding: narrow gap flash welding: for the 50m short rail after cutting, narrow gap welding (gap 8~10mm) is adopted, the welding heat affected zone is ≤20mm (traditional arc welding is 50mm), which significantly reduces the welding residual stress.

[0087] Line fine adjustment: dynamic adjustment based on BIM: import the track alignment data before and after construction into the BIM model, generate fine adjustment vector diagram, guide the tamping machine to adjust with the accuracy of 0.1mm, and finally the track smoothness (TQI index) is ≤2.0 (traditional method is 3.5).

[0088] The application proposes a prefabricated elastic solidified ballast replacement scheme, including process flow and detailed construction scheme. The overall scheme is to replace the old sleeper and solidified ballast with new sleeper and solidified ballast after tamping. For concentrated replacement, the tamping method after cutting is adopted to maximize the construction efficiency; for scattered replacement, the tamping method after cutting is adopted to minimize the damage to the rail.

[0089] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only the principles of the present application. Various changes and improvements can be made without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method of assembling a modular resilient solidified track bed, characterized in that, The method comprises a preparation stage, a replacement stage and a recovery stage. The preparation stage comprises data measurement, temporary gantry crane track laying, both sides and sleeper ballast removal, and rail cutting, wherein: The data measurement is performed by combining a total station and a laser scanner to perform three-dimensional modeling on the track alignment; The temporary gantry crane track laying provides a stable support platform for the gantry crane, ensures the track smoothness and prevents local settlement, and comprises (1) support pier design: determining the longitudinal distance between the support piers, i.e., the distance of the non-removal section and the distance of the removal section; the support pier size is verified by finite element simulation for bending bearing capacity; (2) materials and structures: fast-hardening polymer concrete; glass fiber cloth is laid at intervals, and the tensile strength is greater than or equal to 100 MPa, so as to improve the crack resistance of the support pier; (3) installation process: laying a non-woven fabric isolation layer on the inner side of the formwork; the channel steel is fixed to the support pier by expansion screws, and the lap joint is seamlessly treated; The both sides and sleeper ballast removal: cleaning the working surface to the invert backfill layer to provide an unobstructed construction space for the sleeper replacement, comprising (1) removing the unhardened ballast in layers to the depth of the invert surface; (2) removing the ballast for temporary storage: evenly spreading on the adjacent track or storing in the comprehensive cavern; The rail cutting: releasing the temperature stress of the rail to avoid track deformation caused by thermal expansion and cold contraction during construction, comprising (1) limiting the cutting length, which is determined according to the calculation formula of the rail temperature stress; (2) when ΔT≤20℃, the expansion amount ΔL is matched with the gap design of the clamp plate to completely absorb the expansion amount; (3) the clamp plate is used to connect the cutting rail, and the clamp plate is disassembled daily to cooperate with the rail shifting operation, and the seamless connection is restored after construction; The replacement stage comprises the following steps: 1) removing the fasteners The fasteners in the rail shifting section are removed, and for seamless rails, the length of the removed fasteners is determined according to the difference between the operation temperature and the locked rail temperature; 2) horizontal rail shifting The horizontal rail shifting equipment is installed, including the rail shifting tool, the rail slide and the anti-slip device; the rail shifting tool is used for large super-elevation sections of seamless rails and jointed rails; the rail slide is used for all rail shifting sections; the anti-slip device is used for jointed rail sections with large longitudinal slope; 3) assembling the gantry crane The fasteners are removed, the rail shifting is performed, and the gantry crane is assembled, debugged and new sleepers are unloaded at the same time; 4) unloading new sleepers After the gantry crane is assembled and debugged, the new sleepers are unloaded from the rail flat car by the gantry crane and transported longitudinally to the temporary storage position for replacement sleepers; 5) removing old sleepers The old sleepers are lifted, transported and loaded onto the rail flat car by the gantry crane; after the old sleepers are loaded, the gantry crane is removed and loaded; 6) returning the rail and installing the fasteners ​ ​ ​ Using the rail pushing device or manpower to push back the steel rail, install the fastener, including the fastener of the newly replaced sleeper; 7) New sleeper fine adjustment After the new sleeper is hung on the steel rail by the fastener, the position of the new sleeper is indirectly adjusted by adjusting the position of the steel rail through the lead screw; 8) Mortar bag pouring Pouring the mortar bag at the lower part of the sleeper solidified ballast to re-pour the filling layer mortar; The recovery stage comprises the following steps: 1) Both sides and sleeper ballast recovery Using the subsequent window, re-filling and tamping the ballast on both sides of the line and between sleepers; 3) Steel rail welding For the steel rail with cut joints in the concentrated replacement section, the steel rail welding is performed, and the long rail is replaced according to the situation; 4) Line fine adjustment After all the sleepers are replaced, the track fine adjustment or the lifting and pushing of the track is performed on the construction section to restore the smoothness of the line, and the speed of the construction range is gradually increased. The lateral rail pushing distance is 800-850 mm, the hydraulic pushing device is used, the pushing force is greater than or equal to 10T, and the steel rail is pushed; the surface of the steel rail slide is coated with a polytetrafluoroethylene coating, the friction coefficient is less than or equal to 0.1, and the pushing resistance is reduced by 30%. The new sleeper fine adjustment indirectly adjusts the position of the steel rail by using the bidirectional lead screw, the pitch accuracy is ±0.02 mm, the laser displacement sensor is used to monitor the gap value between adjacent mortar bags, which is less than or equal to 0.3 mm, and the sleeper positioning accuracy is ±0.5 mm.

2. The method of claim 1, wherein, The mortar bag pouring dynamically selects a single sleeper or a double sleeper according to the sleeper spacing, uses the fluidity mortar with a slump of 180±20 mm, and the filling density is greater than or equal to 95%.

3. The method of claim 1, wherein, The steel rail welding uses narrow gap flash welding: for the 50 m short rail after cutting, the welding heat affected zone is less than or equal to 20 mm.

4. The method of claim 1, wherein, The line fine adjustment is a dynamic adjustment based on BIM: the track alignment data before and after construction is imported into the BIM model to generate a fine adjustment vector diagram to guide the lifting and pushing machine to adjust the accuracy to 0.1 mm, and the final line smoothness TQI index is less than or equal to 2.

0.

5. The method of claim 1, wherein, 7. A railway track maintenance method, which is realized by using the prefabricated elastic solidified ballast replacement method of claim 1 when the old sleepers and solidified ballast are replaced by new sleepers and solidified ballast after pushing the rail.

6. The method of claim 1, wherein, ​ ​

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