High-speed railway ballastless track roadbed filler upwarp deformation test system and method

Abstract

The invention relates to a high-speed railway ballastless track subgrade filler upwarp deformation test system and method, and the system comprises a track-subgrade structure system which is copied in a ratio of 1: 1 and comprises a subgrade bed surface layer, a subgrade bed bottom layer, a subgrade body and a track plate; a high-speed train load simulation loading system comprises a traveling frame, a vibration exciter and a balancing weight, wherein the vibration exciter and the balancing weight are carried by the traveling frame. The ventilation system is a ventilation pipe arranged along the width and height directions of the roadbed; the water feeding system comprises a water pipeline located at the bottom layer of the foundation bed and a retention wall located at the top of the roadbed; the roadbed deformation monitoring system comprises a single-point settlement displacement meter, a water content / thermometer, a flange plate, an automatic monitoring system and a wire, and the wire is connected with the single-point settlement displacement meter, the water content / thermometer and the automatic monitoring system. According to the invention, the load, frequency and action time can be accurately controlled, different train operation conditions are simulated, and the actual stress environment of the upper arch section of the iron sulfide filler of the high-speed railway is effectively restored.

Description

Technical Field

[0001] This patent relates to the field of railway subgrade filling tests, and specifically refers to a high-speed railway ballastless track subgrade filling arch deformation test system and method. Background Art

[0002] High-speed railways have extremely high requirements for the smoothness of ballastless tracks. Existing surveys, designs, and construction mainly focus on preventing the subsidence of the roadbed and tracks. However, in recent years, high-speed railway lines in many regions have experienced roadbed arching deformation, which seriously affects the track smoothness and driving safety, and remediation measures need to be taken. Roadbed arching has become one of the difficulties of ballastless track high-speed railway technology, and its occurrence mechanism and remediation methods need to be studied urgently.

[0003] At present, the research on roadbed arching mainly includes two aspects: foundation expansion and filler expansion. The mechanism of foundation expansion is relatively clear, while the research on arching caused by filler expansion started late, involving complex physical and chemical processes. In addition, current research is still mainly focused on cement expansion caused by sulfate erosion, and there is limited understanding of filler expansion caused by chemical erosion of sulfur-containing minerals. On many high-speed railway lines, arching deformation caused by sulfur-containing minerals in the filler has occurred without expansive soil. This deformation has the characteristics of long period, irreversibility, large amount of arching, and difficulty in disease treatment. Studies have shown that the oxidation of sulfide minerals such as pyrite will generate sulfate, which reacts with other minerals to form gypsum, causing the filler volume to expand, thereby causing roadbed arching.

[0004] Existing test technologies mainly focus on frost heave deformation test and dynamic loading test of roadbed. For example, patents (application numbers CN115492174A and CN118309121A) provide test devices, but do not involve experimental research on the arch deformation of roadbed fillers. At present, there is no effective method to reproduce the arching phenomenon of iron sulfide fillers in an experimental environment. Due to the uncontrollability of field tests and the safety requirements of operating lines, existing research is difficult to carry out on actual lines. Summary of the invention

[0005] Aiming at the shortcomings that there is no effective test method for the roadbed arching phenomenon in the prior art, and that it is difficult to carry out field tests based on operating high-speed railways due to the uncontrollable field test conditions and the limitation of not interfering with the normal operation of existing high-speed railway lines, the present invention provides a high-speed railway ballastless track roadbed filling arching deformation test system and test method, which can be used to reveal the occurrence, development and change law of the arching deformation of the high-speed railway ballastless track roadbed filling, and explore the breeding mechanism of the arching deformation of the ballastless track roadbed filling and the threshold conditions for its generation.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] A high-speed railway ballastless track subgrade filler arch deformation test system, comprising:

[0008] Track-subgrade structure system, the track-subgrade structure system is replicated at a 1:1 ratio, including the surface layer of the subgrade bed, the underlying layer of the subgrade bed, the subgrade body and the track slab;

[0009] High-speed train load simulation loading system, including a traveling frame and the exciters and counterweights carried thereon. A force sensor is provided between the frame of the traveling frame and the wheel axle. The wheels of the traveling frame can run along the track and are fixed at a designated position on the track by a rail clamp;

[0010] Ventilation system, which is a ventilation pipe arranged along the width and height directions of the subgrade. A number of ventilation holes are evenly distributed in a plum blossom shape on the ventilation pipe. A layer of breathable net is wrapped outside or inside the ventilation pipe with ventilation holes;

[0011] Water supply system, including a water pipe line located in the underlying layer of the subgrade bed and a water retaining wall located at the top of the subgrade. The water pipe line includes a T-shaped main pipe, a plurality of water supply branch pipes connected side by side to the T-shaped main pipe, and a water tank for supplying water to the water pipes. The water supply branch pipes are arranged along the width direction of the subgrade;

[0012] Subgrade deformation monitoring system, including a single-point settlement displacement meter, a water content / thermometer, a flange, an automatic monitoring system and a wire. The single-point settlement displacement meter and the water content / thermometer are buried in different parts of the subgrade filling. A number of round holes are provided on the flange for burying the single-point settlement displacement meter and the water content / thermometer. The wire connects the single-point settlement displacement meter and the water content / thermometer to the automatic monitoring system.

[0013] Preferably, the subgrade filling is sourced from pyrite-containing filling. The surface layer of the subgrade bed is made of graded crushed stone. The underlying layer of the subgrade bed and the subgrade body are made of Group A / B filling. And the thickness and compaction standard of each layer structure of the subgrade are strictly controlled in accordance with the requirements for high-speed railway subgrade filling.

[0014] Preferably, the exciter is a biaxial exciter, on which a frequency converter is installed.

[0015] Preferably, there are two exciters, with the same frequency and opposite rotation directions.

[0016] Preferably, the counterweight is made of a steel counterweight.

[0017] Preferably, the ventilation pipe is made of a concrete circular pipe with a diameter of 0.3 - 0.5 m. The hole spacing of the ventilation holes is 2 - 3 m, and the diameter is 0.05 - 0.1 m.

[0018] Preferably, a number of water holes are evenly distributed in a plum blossom shape on the water pipes of the water pipe line. A breathable net is wrapped outside or inside the water pipe to prevent subgrade filling from entering the water holes and blocking the water pipes.

[0019] Preferably, the water pipe network located at the bottom layer of the subgrade bed conducts water along the T-shaped main pipe and the water distribution branch pipes through the water tank to the bottom of the subgrade bed, and the water seeps into the bottom subgrade filler through the water holes on the water pipes, so as to simulate the influence of the water seepage state at the subgrade base on the vulcanized railway subgrade filler.

[0020] Preferably, the water retaining wall surrounds the top of the subgrade in a circle, and simulates the working conditions of rainwater infiltration affecting the surface subgrade filler and rainwater infiltration by converging rainfall or pumping and draining water.

[0021] On the other hand, the present invention also discloses a test method for the arching deformation test system of the ballastless track subgrade of high-speed railway based on the above, including the following steps:

[0022] S1, Test preparation: Determine the test purpose and test plan, and prepare the materials and equipment required for the test;

[0023] S2, Construction preparation: Level the test site, and reinforce or excavate and replace the soft foundation according to the requirements of high-speed railway subgrade foundation treatment;

[0024] S3, Subgrade filling: Feed, level and compact the prepared subgrade filler layer by layer, and detect the quality after each layer of filling is completed;

[0025] S4, Burying of ventilation pipes and water pipes: During the subgrade filling process, bury ventilation pipes and water pipes at the designated positions according to the design requirements;

[0026] S5, Installation of monitoring system: After the subgrade filling is completed, at the top position of the subgrade, bury single-point settlement displacement gauges and water content / thermometers through drilling, and backfill and compact the drilling holes after completion;

[0027] S6, Pouring of water retaining wall: Lay the water retaining wall on the top of the subgrade, and trim the slope, and then complete the laying of the track slab, base and support layer;

[0028] S7, Debugging of loading system: Debug the simulated loading system for high-speed train loads to ensure that it can work according to the predetermined loading system;

[0029] S8, Formal loading test: Conduct dynamic loading according to the predetermined loading system to simulate the load action during train operation; During the loading process, monitor and record data in real time, observe the arching deformation of the subgrade filler, and take pictures or videos if necessary;

[0030] S9, Tests under different working conditions: By changing the settings of the water pipes and ventilation pipes, simulate the seepage + ventilation condition, seepage condition, ventilation condition and natural condition, conduct tests under the condition of open water supply without additional load, and record the monitoring data;

[0031] S10, data collection and analysis: after the test, all measurement data are collected, processed and analyzed, and the causes and laws of the arch deformation of the roadbed filler are analyzed;

[0032] S11, test result collation and report: based on the analysis results, write a test report, which includes the test purpose, method, process, results and conclusions, and proposes prevention and control measures for the arch deformation of roadbed filler;

[0033] S12, test site cleaning: After the test, dismantle the test model and clean up the test site.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention adopts a 1:1 scale track-roadbed structure model to ensure that the structure, material and mechanical properties are consistent with the actual high-speed railway ballastless track roadbed, making the test results more engineering applicable. Through the high-speed train load simulation loading system, the load size, frequency and action time can be accurately controlled to simulate different train operating conditions, thereby effectively restoring the actual stress environment of the upper arch section of the high-speed railway iron sulfide filler and ensuring the authenticity and reliability of the test data.

[0036] (2) The test system can effectively control oxygen supply and water infiltration by setting up a retaining wall on the top of the roadbed, a water pipe at the bottom of the roadbed, and a vent pipe inside the roadbed, and accurately simulate the expansion process of iron sulfide filler under the chemical action of water and rock. In addition, by adjusting the settings of the retaining wall, water pipe and vent pipe, a variety of test conditions such as seepage + ventilation conditions, seepage conditions alone, ventilation conditions alone and natural conditions can be established, so as to systematically study the main controlling factors affecting the expansion deformation of the filler and reveal the laws of arch deformation under different environmental conditions.

[0037] (3) The present invention adopts a roadbed deformation monitoring system, which can deploy single-point settlement displacement meters and moisture / temperature meters at different depths to accurately monitor the roadbed deformation, moisture content and temperature at different locations. At the same time, the system is combined with an automated monitoring system to achieve real-time and continuous data collection, ensuring the stability and reliability of the measurement data, and providing accurate experimental data support for the study of filler expansion deformation mechanism and prevention and control technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A high-speed railway ballastless track subgrade filler arching deformation test system according to an embodiment of the present invention;

[0039] Figure 2 A high-speed train load simulation loading system according to an embodiment of the present invention;

[0040] Figure 3A schematic diagram of a ventilation pipe / water pipe opening according to an embodiment of the present invention;

[0041] Figure 4 The flange of the roadbed deformation monitoring system according to an embodiment of the present invention;

[0042] Figure 5 A schematic diagram of the buried monitoring components of the roadbed deformation monitoring system according to an embodiment of the present invention;

[0043] Figure 6 It is a schematic diagram of deformation monitoring working conditions and cross-section arrangement of an embodiment of the present invention.

[0044] Reference numerals: 1-track-roadbed structure system; 1.1-bed surface layer; 1.2-bed bottom layer; 1.3-roadbed body; 1.4-track plate; 2-high-speed train load simulation loading system; 2.1-vibrator; 2.2-frequency converter; 2.3-counterweight; 2.4-force sensor; 2.5-rail clamp; 2.6-travel frame; 3-ventilation system; 3.1-ventilation hole; 3.2-breathable net; 4-water distribution system; 4.1-water pipeline; 4.1.1-water branch pipe; 4.1.2-T-type main pipe; 4.1.3-water tank; 4.2-water retaining wall; 5-roadbed deformation monitoring system; 5.1-single point settlement displacement meter; 5.2-water content / temperature meter; 5.3-flange; 5.3.1-positioning hole; 5.3.2-wiring hole; 5.4-automatic monitoring system; 5.5-conductor. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the present invention.

[0046] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0047] The present embodiment discloses a high-speed railway ballastless track subgrade filler arch deformation test system, including a track-subgrade structure system 1. The track-subgrade structure system 1 is a 1:1 scale replica, that is, the test system is constructed according to the size and structure of the actual high-speed railway subgrade to ensure the accuracy of the test results and engineering applicability.

[0048] like Figure 1 As shown, the track-roadbed structure system 1 includes a subgrade surface layer 1.1, a subgrade bottom layer 1.2, a subgrade body 1.3 and a track plate 1.4. The subgrade filler comes from the iron sulfide filler. The subgrade surface layer adopts graded crushed stone, and the subgrade bottom layer and the subgrade body adopt A / B group fillers. The thickness and compaction standard of each layer of the subgrade structure are strictly controlled in accordance with the requirements for high-speed railway subgrade filling to ensure that the track-roadbed structure system is consistent with the actual situation of the upper arch section of the high-speed railway iron sulfide filler subgrade.

[0049] The roadbed filler is derived from the iron sulfide filler. The main component of this filler is iron sulfide minerals, which can react chemically under the action of oxygen and water to produce volume expansion, thereby causing the roadbed to bulge and deform. Therefore, the selection of this type of filler can simulate the bulging phenomenon caused by the expansion of fillers during the operation of high-speed railways. The surface layer 1.1 of the subgrade uses graded crushed stone. This graded crushed stone has good drainage and stability, can provide the necessary support and stability for the roadbed, and prevent excessive accumulation of water on the surface of the roadbed, and avoid excessive influence of water and soil on the expansion reaction of the filler. The bottom layer 1.2 of the subgrade and the roadbed body 1.3 use A / B group fillers. This filler combination can provide appropriate strength and compaction, ensuring that the roadbed has good stability and uniformity when bearing loads. In order to ensure the long-term stability of the roadbed, the thickness and compaction standards of each layer of the roadbed structure are strictly controlled in accordance with the requirements for high-speed railway roadbed filling. During the test, the thickness, compaction and material selection of the filler must be consistent with the design requirements of the actual high-speed railway roadbed to ensure the reliability of the test results and engineering applicability.

[0050] like Figure 2 As shown, the high-speed train load simulation loading system 2 includes a carriage 2.6 and an exciter 2.1 and a counterweight 2.3 carried thereon. The carriage 2.6 is used to simulate the load effect of a high-speed train and can move along the track to ensure that the loading process conforms to the actual train operation status. A force sensor 2.4 is provided between the frame of the carriage 2.6 and the wheel axle to measure the dynamic load applied by the loading system on the track to ensure that the loading system can accurately simulate the train load size and its changes. The wheels of the carriage 2.6 can move along the track and be fixed to a specified position on the track by a rail clamp 2.5 to ensure the stability and controllability of the load effect during the test.

[0051] Furthermore, the vibrator 2.1 is a biaxial vibrator. The characteristic of a biaxial vibrator is that it generates vibrations through the rotation of two shafts. This kind of vibration can simulate the load effect when a train passes through the track, and is especially suitable for simulating the dynamic load of high-speed railway trains. A frequency converter 2.2 is installed on the vibrator 2.1. The function of the frequency converter is to adjust the vibration frequency of the vibrator, and it can adjust the magnitude and frequency of the vibration according to the test requirements, so as to more accurately simulate the running states of different trains. In this system, there are two vibrators 2.1, and the frequencies of the two vibrators are the same while the rotation directions are opposite. Such a setting can ensure that the vibration direction and frequency generated by the vibrator are closer to the load vibration generated during the actual running of high-speed trains, and the simulation effect is more realistic. The counterweight 2.3 is made of a steel counterweight. The steel counterweight has a large mass and stability, and can provide a stable loading force to ensure that the loading system can accurately simulate the load condition when a train passes through the subgrade. The loading system can accurately control the magnitude, frequency and action time of the load through the mounted vibrator 2.1 and counterweight 2.3 to simulate different train operation conditions.

[0052] As Figure 3 shown, the ventilation system 3 arranges ventilation pipes 3 along the width and height directions of the subgrade. A number of ventilation holes 3.1 are evenly distributed in a plum blossom shape on the ventilation pipes 3. The function of the ventilation holes 3.1 is to enable oxygen to penetrate into the filler to simulate the oxidation process of the filler in an air environment. Since the filler may contain sulfide minerals such as pyrite inside, it will undergo an oxidation reaction under the action of a water-oxygen environment, resulting in volume expansion and causing the subgrade to arch and deform. Therefore, a layer of breathable mesh 3.2 is wrapped outside or inside the ventilation pipe 3 with ventilation holes 3.1. The function of the breathable mesh 3.2 is to prevent the subgrade filler particles from entering the ventilation pipe 3 and causing blockage, ensuring that the ventilation system 3 can operate effectively for a long time.

[0053] Furthermore, the ventilation pipe is a concrete circular pipe with a diameter of 0.3 - 0.5 m. The hole spacing of the ventilation holes 3.1 should be 2 - 3 m. If the diameter of the ventilation hole is too small, it will affect the function of the ventilation hole, and if it is too large, it will affect the overall strength of the ventilation pipe. It should be 0.05 - 0.1 m. In actual experiments, the reasonable hole spacing and hole diameter can be determined through tests. Through this design, the ventilation pipe can achieve effective oxygen supply during the test, promote the oxidation reaction of sulfide minerals (such as pyrite) in the filler, thereby triggering the process of expansion deformation and simulating the real arching phenomenon of the high-speed railway subgrade.

[0054] As Figure 1As shown, the water supply system 4 includes a water pipe 4.1 located at the bottom layer 1.2 of the subgrade and a water retaining wall 4.2 located at the top of the roadbed. The function of the water pipe 4.1 is to provide an environment for simulating groundwater seepage, while the water retaining wall 4.2 is used to control the infiltration of surface water to simulate the influence of different hydrological conditions on the expansion and deformation of the filler. The water pipe 4.1 includes a T-type main pipe 4.1.2 and a plurality of water branch pipes 4.1.1 connected side by side to the T-type main pipe 4.1.2. The water branch pipes 4.1.1 are arranged along the width direction of the roadbed so that water can evenly penetrate into the roadbed filler. In order to ensure that the water pipe can withstand the pressure of the overlying filler, the water pipe should be made of a steel pipe with a certain rigidity. Like the vent pipe, a plurality of water holes are evenly distributed in a plum blossom shape on the water pipe, and a layer of air permeable net is wrapped on the outside or inside of the water pipe with water holes to prevent the roadbed filler from entering through the water holes and blocking the water pipe. The water pipe 4.1 located at the bottom layer 1.2 of the subgrade passes water to the bottom of the subgrade through the water tank 4.1.3 along the T-shaped main pipe 4.1.2 and the water branch pipe 4.1.1. The water tank 4.1.3 is used to provide a stable water source to ensure sufficient water supply during the test. The water pipe 4.1 includes a T-shaped main pipe 4.1.2 and multiple water branch pipes 4.1.1. These branches are arranged along the width of the subgrade to ensure that water can evenly penetrate into the bottom layer of the subgrade filler. Water seeps into the bottom subgrade filler through the water holes on the water pipe, simulating the water seepage state of the subgrade base, which is caused by groundwater or precipitation penetrating into the filler through the bottom of the subgrade, thereby affecting the expansion reaction of the filler. This design can effectively reproduce the expansion process of the high-speed railway subgrade filler under the action of water-rock chemistry, especially the expansion deformation mechanism of iron sulfide filler, and thus simulate its behavior and changes in actual engineering.

[0055] like Figure 5-6As shown, the roadbed deformation monitoring system 5 includes a single-point settlement displacement meter 5.1, a water content / temperature meter 5.2, a flange 5.3, an automatic monitoring system 5.4 and a conductor 5.5. The single-point settlement displacement meter 5.1 and the water content / temperature meter 5.2 are buried in different parts of the roadbed filling material. The single-point settlement displacement meter 5.1 is used to monitor the deformation of the roadbed at different depths, while the water content / temperature meter 5.2 is used to monitor the temperature and water content of the roadbed filling material at different depths. These data are crucial for analyzing the expansion mechanism of the filling material. A plurality of circular holes are provided on the flange 5.3, and the diameter meets the requirements for burying the single-point settlement displacement meter 5.1 and the water content / temperature meter 5.2. A specific depth is drilled from the circular hole position to the roadbed filling material, and the single-point settlement displacement meter 5.1 and the water content / temperature meter 5.2 are placed at a specific depth from the drilled hole and installed, so as to achieve the purpose of installing monitoring components at different positions. The same number of connecting wires 5.5 as the single-point settlement displacement meter 5.1 and the moisture content / temperature meter 5.2 are arranged on the flange 5.3. The wires 5.5 are connected to the automatic monitoring system 5.4 on one side of the track-roadbed structure system 1 in an appropriate manner to realize the introduction of collected data into the automatic monitoring system. The roadbed monitoring system 5 is used to monitor the real-time status of the roadbed under the working state of the high-speed train load simulation loading system. The use of the automatic monitoring system can realize real-time and continuous data collection and ensure the reliability and stability of the data. The flange 5.3 is provided with positioning holes 5.3.1 and wiring holes 5.3.2. The positioning holes 5.3.1 are used to accurately locate and fix the monitoring equipment, and the wiring holes 5.3.2 are used to connect the sensor and the wire 5.5 of the automatic monitoring system to ensure that the signal can be transmitted reliably and the continuity of data collection is realized.

[0056] In addition, another embodiment of the present invention further discloses a test method based on the above-mentioned high-speed railway ballastless track subgrade filler arch deformation test system, comprising the following steps:

[0057] S1, Test preparation: determine the test purpose and test plan, clarify the loading, monitoring and environmental control conditions required for the test, and prepare relevant materials and equipment, including iron sulfide filler for simulating roadbed filler, high-speed train load simulation loading system 2, ventilation system 3, water ventilation system 4, roadbed deformation monitoring system 5, etc., to make full preparations for subsequent construction.

[0058] S2, Construction Preparation: Level the test site to ensure the stability of the test system and the accuracy of the test data, and reinforce or excavate and replace the soft foundation in accordance with the high-speed railway subgrade foundation treatment requirements to ensure that the test environment can truly reproduce the foundation conditions of the high-speed railway subgrade.

[0059] S3, roadbed filling: The prepared roadbed filler is loaded, leveled and rolled in a layered manner. After each layer is completed, quality inspection is required to ensure that the density and uniformity of the filler meet the high-speed railway roadbed filling standards and that the test environment is consistent with the actual project.

[0060] S4, burying of ventilation pipes and water pipes: During the roadbed filling process, ventilation pipes 3 and water pipes 4.1 are buried at designated locations according to design requirements. Ventilation pipes 3 are used to provide oxygen to cause oxidation reaction of sulfide minerals in the filler, while water pipes 4.1 are used to simulate the effects of groundwater infiltration and rainfall infiltration on filler expansion, so as to ensure that the test system can effectively reproduce the entire process of filler expansion and deformation under the action of water and air.

[0061] S5, installation of monitoring system: after the roadbed is completed, a single-point settlement displacement meter 5.1 and a moisture content / temperature meter 5.2 are buried through a borehole at the top of the roadbed to ensure that the deformation, moisture content and temperature changes of the fillers at different depths can be monitored in real time. After the burial is completed, the borehole is backfilled and compacted to ensure the stability of the monitoring instrument and the accuracy of the data.

[0062] S6, retaining wall casting: a retaining wall 4.2 is laid on the top of the roadbed. The function of the retaining wall 4.2 is to control the convergence and infiltration of surface water during the test, to ensure that the hydrological conditions under different working conditions are controllable, and to trim the slopes at the same time to prevent the lateral movement of the filler during the test from affecting the test results. Subsequently, the track plate 1.4, the base and the supporting layer are laid to ensure that the test environment can truly simulate the overall stress state of the high-speed railway ballastless track structure.

[0063] S7, loading system debugging: debug the high-speed train load simulation loading system 2 to ensure that the components such as the vibration exciter 2.1, the counterweight block 2.3, and the force sensor 2.4 can work normally according to the predetermined loading system, and check the running status of the carriage 2.6 on the track to ensure that the load application process is stable and reliable. Through the above test method, the occurrence, development and change law of the arch deformation of the subgrade filler of the high-speed railway ballastless track can be fully simulated, and the key data of the filler deformation under different working conditions can be obtained, providing a scientific basis for studying the filler expansion mechanism and prevention and control measures.

[0064] S8, formal loading test: dynamic loading is performed according to the predetermined loading system to simulate the load effect of the train during operation. During the test, the carriage 2.6 runs along the track, the vibration load generated by the exciter 2.1 acts on the track-roadbed structure system 1, the counterweight 2.3 provides additional load, and the force sensor 2.4 records the loading situation in real time. During the loading process, real-time monitoring and recording of data, observation of the arch deformation of the roadbed filler, and taking photos or videos when necessary to obtain detailed deformation process.

[0065] S9, different working condition test: by changing the settings of water pipes and ventilation pipes, seepage + ventilation conditions, seepage conditions, ventilation conditions and natural conditions are simulated. The water pipe controls the water supply, and the ventilation pipe controls the oxygen supply. Under different working conditions, the degree of water-gas chemical reaction inside the filler is different, resulting in differences in the expansion degree and arch deformation of the filler. In the test, the test was carried out under open water replenishment conditions without additional load, and the monitoring data was recorded to analyze the influence of different environmental factors on the expansion of the filler.

[0066] S10, Data collection and analysis: After the test, all measurement data are collected, including the roadbed deformation data measured by the single-point settlement displacement meter 5.1, the moisture and temperature change data inside the filler measured by the moisture content / thermometer 5.2, and the deformation response under dynamic load recorded by the automatic monitoring system 5.4. During the data analysis process, the arch deformation under different working conditions is compared, the causes and laws of filler expansion are analyzed, and the chemical expansion mechanism of iron sulfide filler in a water-oxygen environment is explored.

[0067] S11, Test results collation and report: Based on the analysis results, write a test report, which includes the test purpose, method, process, results and conclusions. According to the deformation law of filler under different working conditions, put forward prevention and control measures to provide technical support for the control of the deformation of the filler on the ballastless track of high-speed railway.

[0068] S12, test site cleaning: After the test, dismantle the test model, including removing the loading system 2, ventilation system 3 and water supply system 4, and recover all monitoring equipment 5, clean up the test site, and ensure that the test area is restored to a usable state.

[0069] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may also be combined, the steps may be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the above embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the above embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-speed railway ballastless track subgrade filler arch deformation test system, characterized in that: include: A track-roadbed structure system (1), wherein the track-roadbed structure system (1) is a 1:1 scale replica, comprising a subgrade surface layer (1.1), a subgrade bottom layer (1.2), a roadbed body (1.3) and a track slab (1.4); A high-speed train load simulation loading system (2) comprises a carriage (2.6) and a vibration exciter (2.1) and a counterweight (2.3) mounted thereon, wherein a force sensor (2.4) is arranged between the carriage (2.6) and the wheel axle, and the wheels of the carriage (2.6) can travel along a track and be fixed to a designated position of the track by a rail clamp (2.5); The ventilation system (3) is a ventilation pipe arranged along the width and height of the roadbed, a plurality of ventilation holes (3.1) are evenly distributed in a plum blossom shape on the ventilation pipe, and a layer of air permeable net (3.2) is wrapped on the outside or inside of the ventilation pipe with the ventilation holes; The water supply system (4) comprises a water supply pipeline (4.1) located at the bottom of the subgrade and a water retaining wall (4.2) located at the top of the roadbed, wherein the water supply pipeline (4.1) comprises a T-shaped main pipe (4.1.2) and a plurality of water supply branches (4.1.1) connected in parallel to the T-shaped main pipe, and a water tank (4.1.2) for supplying water to the water supply pipeline 4.1.3), the water branch pipe (4.1.1) is arranged along the width direction of the roadbed; A roadbed deformation monitoring system (5) comprises a single-point settlement displacement meter (5.1), a water content / temperature meter (5.2), a flange (5.3), an automatic monitoring system (5.4) and a conductor (5.5); the single-point settlement displacement meter (5.1) and the water content / temperature meter (5.2) are buried in different parts of the roadbed filler; a plurality of circular holes are provided on the flange (5.3) for burying the single-point settlement displacement meter (5.1) and the water content / temperature meter (5.2); and the conductor (5.5) connects the single-point settlement displacement meter (5.1) and the water content / temperature meter (5.2) with the automatic monitoring system (5.4).

2. The high-speed railway ballastless track subgrade filler arch deformation test system according to claim 1 is characterized in that: The roadbed filler is derived from iron sulfide-containing filler, the subgrade surface layer (1.1) is made of graded crushed stone, the subgrade bottom layer (1.2) and the roadbed body (1.3) are made of A / B group fillers, and the thickness and compaction standard of each layer of the roadbed structure are strictly controlled in accordance with the requirements for high-speed railway roadbed filling.

3. The high-speed railway ballastless track subgrade filler arch deformation test system according to claim 2 is characterized in that: The exciter (2.1) is a dual-axis exciter, on which a frequency converter (2.2) is installed.

4. The high-speed railway ballastless track subgrade filler arch deformation test system according to claim 3 is characterized in that: There are two vibrators (2.1) with the same frequency and opposite rotation directions.

5. The high-speed railway ballastless track subgrade filler arch deformation test system according to claim 2 is characterized in that: The counterweight block (2.3) is a steel counterweight block.

6. The high-speed railway ballastless track subgrade filler arch deformation test system according to any one of claims 1 to 5, characterized in that: The ventilation pipe is a concrete circular pipe with a diameter of 0.3-0.5m. The ventilation holes (3.1) have a hole spacing of 2-3m and a diameter of 0.05-0.1m.

7. The high-speed railway ballastless track subgrade filler arch deformation test system according to claim 6 is characterized in that: The water pipe of the water passage pipeline (4.1) is provided with a plurality of water holes evenly distributed in a plum blossom shape, and a breathable net is wrapped on the outside or inside of the water pipe to prevent roadbed fillers from entering through the water holes and clogging the water pipe.

8. The high-speed railway ballastless track subgrade filler camber deformation test system according to claim 7 is characterized in that: The water pipe (4.1) located at the bottom layer (1.2) of the subgrade passes water to the bottom of the subgrade through a water tank (4.1.3) along a T-shaped main pipe (4.1.2) and a water branch pipe (4.1.1), and the water seeps into the bottom subgrade filler through the water holes on the water pipe, thereby simulating the influence of the water seepage state of the subgrade base on the vulcanized railway subgrade filler.

9. The high-speed railway ballastless track subgrade filling material uplift deformation test system according to claim 8, characterized in that: The retaining wall (4.2) is formed in a circle along the top of the roadbed, and simulates rainwater infiltration by collecting rainfall or pumping out drainage to affect the surface roadbed filling material and rainwater infiltration.

10. A test method based on the high-speed railway ballastless track subgrade filler camber deformation test system according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, test preparation: determine the test purpose and test plan, and prepare the materials and equipment required for the test; S2, construction preparation: level the test site and reinforce or excavate and replace the soft foundation according to the requirements for high-speed railway subgrade foundation treatment; S3, roadbed filling: loading, leveling and rolling the prepared roadbed filling material in layers, and testing the quality of each layer after completion; S4, burying of ventilation pipes and water pipes: During the roadbed filling process, bury ventilation pipes and water pipes at designated locations according to design requirements; S5, installation of monitoring system: after the roadbed is completed, a single-point settlement displacement meter (5.1) and a moisture content / temperature meter (5.2) are buried through a drill hole at the top of the roadbed. After the burial is completed, the drill hole is backfilled and compacted; S6, retaining wall pouring: laying the retaining wall (4.2) on the top of the roadbed and trimming the slope, followed by laying the track slab (1.4), base and support layer; S7, loading system debugging: debugging the high-speed train load simulation loading system (2) to ensure that it can work according to the predetermined loading system; S8, formal loading test: dynamic loading is carried out according to the predetermined loading system to simulate the load effect of the train in operation; during the loading process, real-time monitoring and recording of data is carried out to observe the arch deformation of the roadbed filling material, and photographing or recording is carried out when necessary; S9, tests under different working conditions: by changing the settings of water pipes and ventilation pipes, simulating seepage + ventilation conditions, seepage conditions, ventilation conditions and natural conditions, conducting tests under open water replenishment conditions without additional loads, and recording monitoring data; S10, data collection and analysis: after the test, all measurement data are collected, processed and analyzed, and the causes and laws of the arch deformation of the roadbed filler are analyzed; S11, test result collation and report: based on the analysis results, write a test report, which includes the test purpose, method, process, results and conclusions, and proposes prevention and control measures for the arch deformation of roadbed filler; S12, test site cleaning: After the test, dismantle the test model and clean up the test site.

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