A high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions

Abstract

The application belongs to the field of cold region track engineering and subgrade engineering, and specifically discloses a high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions, which comprises a programmable high-low temperature test box for controlling the alternating change of environmental temperature, a rainfall simulation device for adjusting according to different rainfall in cold regions, a solar radiation simulation device for adjusting according to different illumination in cold regions, a ballastless track structure composed of unit block type structure, a subgrade structure composed of three-layer structure, and a data acquisition and monitoring module for monitoring and collecting deformation displacement, temperature, moisture and radiation data in real time. Through the device, real-time monitoring of relevant parameters such as the temperature of the high-speed rail ballastless track, deformation, the temperature of the subgrade, moisture and deformation in cold regions can be realized, the freezing depth of the subgrade and the contribution of each soil layer in frost heaving deformation can be determined, and the influence of the ballastless track on the freezing characteristics of the subgrade can be further analyzed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fault prediction and health management of track engineering and subgrade engineering in cold regions, and particularly relates to a high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions. BACKGROUND

[0002] In recent years, with the vigorous development of China's transportation infrastructure, the operating mileage of high-speed railways in severe cold regions has increased year by year. As the third largest permafrost country in the world, the seasonal frozen soil area in China accounts for about 53.5%, and the perennial frozen soil area accounts for about 21.5%. The average temperature in winter of the seasonal frozen soil area is basically below 0℃, and the minimum temperature in some extreme areas can reach -50℃. In recent years, with the vigorous development of China's transportation infrastructure, the total operating mileage of high-speed railways in severe cold regions has exceeded 8000 km. For China's high-speed railways, ballastless tracks are widely used in lines with a design speed of 350 km / h due to their high smoothness, good stability, and less maintenance. Ballastless tracks are mainly made of concrete pouring, and their structure has a large stiffness, but the deformation adaptability of the underlying foundation is poor. In the seasonal frozen soil area, the roadbed soil undergoes at least one freeze-thaw cycle every year, which changes and redistributes the temperature field, moisture field and deformation field of the roadbed, which will cause the roadbed to frost heave and arch, and the ballastless track will follow the deformation, which will seriously threaten the safety of train operation

[0003] Prognostics Health Management (PHM) is an upgrade development of Condition Based Maintenance (CBM) to meet the requirements of self-support and self-diagnosis. It emphasizes the state perception in asset equipment management, monitors the health condition of equipment, the frequency and cycle of failure, and predicts the occurrence of failure through data monitoring and analysis, thereby greatly improving the operation and maintenance efficiency.

[0004] Among them, the left and right slopes of the high-speed railway subgrade are the key factors causing uneven frost heaving of the subgrade due to different solar radiation amounts. Different strike angles cause changes in the temperature of the upper part of the subgrade and the frost heaving amount of the ground surface, causing differential deformation of the ballastless track. Therefore, deformation control of the subgrade is the core of high-speed railway design and a key factor to realize safe and stable operation of trains.

[0005] For traditional ballastless track-subgrade structure field tests, various uncontrollable factors on site make it difficult to carry out research on the freezing characteristics of ballastless track-subgrade structures under various working conditions. For existing ballastless subgrade frost heaving deformation test methods, the use of full-scale track-subgrade dynamic test models has a long cycle and high cost. SUMMARY

[0006] To solve the problems in the prior art, the application provides a high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions, so that the temperature, deformation of the high-speed rail ballastless track and the temperature, moisture and frost heaving deformation state of the subgrade under different climate conditions can be quickly mastered. The freezing depth of the subgrade and the contribution degree of each soil layer in the frost heaving deformation can be determined through the device, and the influence of the ballastless track on the freezing characteristics of the subgrade is further analyzed, thereby solving the problems mentioned in the background art.

[0007] To achieve the above object, the application provides the following technical scheme: a high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions, the device comprising a programmable high-low temperature test box for controlling the alternating change of the environmental temperature, a rainfall simulation device for adjusting according to different rainfall in cold regions, a solar radiation simulation device for adjusting according to different illumination in cold regions, a ballastless track structure composed of unit block type structure, a subgrade structure composed of three-layer structure, and a data acquisition and monitoring module for monitoring and collecting deformation displacement, temperature, moisture and radiation data in real time.

[0008] The ballastless track structure comprises a track slab layer, a self-compacting concrete layer and a base plate layer; the ballastless track structure adopts a unit block type structure, that is, three track slab layer unit blocks and three self-compacting concrete layer unit blocks are connected above the base plate layer; the track slab layer, the self-compacting concrete layer and the base plate layer are all made of cement.

[0009] The subgrade structure comprises a subgrade surface layer, a subgrade bottom layer and a lower fill embankment; the subgrade surface layer adopts graded gravel, and the subgrade bottom layer and the lower fill embankment both adopt A / B group fillers; only the ballastless track structure is laid on the right side of the upper surface of the subgrade structure, and no ballastless track structure is laid on the left side of the upper surface of the subgrade structure.

[0010] Preferably, the programmable high-low temperature test box comprises a test box body, a core refrigeration unit, a PLC control system, a test box door and an observation window arranged on the front of the test box body, a fan and an electric heating wire arranged at the rear end of the box body; the core refrigeration unit is a plurality of refrigeration compressors; the PLC control system adopts a Delta controller, the temperature control range is-60℃-80℃, the equipment operation power is 55kW, the alternating change of the simulated environmental temperature is used, and the overall error of the temperature control in the box is kept at 1℃-±0.5℃.

[0011] Preferably, the rainfall simulation device comprises a water storage tank, a water pump, a liquid transmission pipeline and a rain shower nozzle arranged outside the test box; the water pump is arranged in the water storage tank and connected with the power supply through an electromagnetic valve, and is used for controlling the rainfall amount, rainfall speed and rainfall time of the rainfall simulation device; the water outlet of the water pump is connected with the rain shower nozzle below the top of the test box body through the liquid transmission pipeline.

[0012] Preferably, the solar radiation simulation device is a plurality of adjustable ultraviolet lamps, which are symmetrically and uniformly arranged below the top of the test box and used for simulating different solar radiation angles and radiation amount changes.

[0013] Preferably, the data acquisition and monitoring module comprises a radiation sensor, a frost heave displacement meter, a temperature sensor, a moisture sensor, a laser displacement sensor and a data acquisition instrument; the data acquisition instrument is connected with the radiation sensor, the frost heave displacement meter, the temperature sensor, the moisture sensor and the laser displacement sensor to monitor and acquire the deformation displacement, temperature, moisture and radiation data of the ballastless track-subgrade in real time.

[0014] Preferably, the temperature sensor is arranged inside the ballastless track structure and the subgrade structure and used for acquiring the temperature change of the ballastless track and the subgrade; the specific arrangement comprises: 1) the temperature sensor is arranged symmetrically at the left side of the center of the cross section of the subgrade structure, the center of the bottom plate layer of the ballastless track and the lower part of the subgrade, and is arranged at a position 0.02 m below the top surface of the subgrade structure; the vertical spacing from top to bottom is 0.1 m, and there are totally 15 temperature sensors, which are used to monitor the horizontal and vertical temperature change rules of the subgrade structure during the freezing process; 2) the temperature sensor is arranged vertically along the center of the ballastless track, and there are totally 3 temperature sensors; two of which are arranged on the upper surface of the track plate layer and the middle part of the track plate layer, and one of which is arranged in the middle part of the bottom plate layer, which are used to monitor the temperature change rules of the ballastless track structure at different vertical positions during the freezing process.

[0015] Preferably, the moisture sensor is arranged inside the subgrade structure and used for acquiring the moisture change of the subgrade; the moisture sensor is arranged symmetrically at the left side of the center of the cross section of the subgrade structure, the center of the bottom plate layer of the ballastless track and the lower part of the subgrade, and is arranged at a position 0.04 m below the top surface of the subgrade structure; the vertical spacing from top to bottom is 0.1 m, and there are totally 15 moisture sensors, which are used to monitor the horizontal and vertical moisture change rules of the subgrade structure during the freezing process.

[0016] Preferably, the frost heave displacement meter is arranged inside the subgrade structure and used for acquiring the frost heave deformation of the subgrade at different depths; the frost heave displacement meter is arranged at the center of the subgrade and the center of the left side of the subgrade, and there are totally 2 frost heave displacement meters, which are used to monitor the frost heave deformation change rules of the soil body at different depths of the subgrade during the freezing process.

[0017] Preferably, the laser displacement sensor is arranged on the laser displacement sensor clamping device on the left and right sides of the test box, and there are totally 3 laser displacement sensors; the angle and height position of the laser displacement sensor are adjusted freely through the laser displacement sensor clamping device, which is convenient for monitoring the frost heave deformation rules of the left and right side slopes of the ballastless track and the subgrade.

[0018] Preferably, the radiation sensors are arranged at the center of the upper surface of the roadbed structure and the left and right side slopes of the roadbed, and the total number of the radiation sensors is three, which are used to monitor the variation of the radiation received by the roadbed surface.

[0019] The application has the advantages that: the application uses the built scale high-speed rail ballastless track-roadbed model to perform tests in the programmable high-low temperature test box which provides stable temperature and humidity working environment, proposes a high-speed rail ballastless track-roadbed freezing characteristic simulation test device based on meteorological conditions in cold regions, reveals the development and variation of the temperature, deformation of the ballastless track structure and the temperature, moisture and frost heaving deformation of the roadbed structure by changing the environmental factors such as temperature, rainfall and radiation, and determines the freezing depth of the roadbed and the contribution degree of the frost heaving deformation of each soil layer, and can further analyze the influence of the ballastless track on the freezing characteristics of the roadbed. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the high-speed rail ballastless track-roadbed freezing characteristic simulation test device based on meteorological conditions in cold regions in the embodiments of the application;

[0021] Figure 2 It is a front view of the simulation test device in the embodiments of the application;

[0022] Figure 3 It is a schematic diagram of the data acquisition and monitoring section position of the ballastless track-roadbed in the embodiments of the application;

[0023] Figure 4 It is a schematic diagram of the setting of each sensor in the ballastless track-roadbed structure in the embodiments of the application;

[0024] Figure 5 It is a schematic diagram of the A part in Figure 4 It is a schematic diagram of the A part in

[0025] Figure 6 It is a schematic diagram of the B part in Figure 4 It is a schematic diagram of the B part in

[0026] In the figure, 1 is a test box body; 2 is an observation window; 3 is a PLC control system; 4 is a test box door; 5 is a rain shower nozzle; 6 is a base bed surface layer; 7 is a base bed bottom layer; 8 is a lower fill embankment; 9 is an adjustable ultraviolet lamp; 10 is a liquid transmission pipeline; 11 is a ballastless track structure; 12 is a refrigeration compressor; 13 is a water storage tank; 14 is a water outlet; 15 is a track plate layer; 16 is a self-compacting concrete layer; 17 is a base plate layer; 18 is a radiation sensor; 19 is a frost heaving displacement meter; 20 is a temperature sensor; 21 is a moisture sensor; 22 is a laser displacement sensor; and 23 is a laser displacement sensor clamping device. DETAILED DESCRIPTION

[0027] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below, obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present application.

[0028] It should be noted that the embodiments and features in the present application can be combined with each other without conflict. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0029] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] The present application uses an indoor small-size model to approximately replace a large-scale test, and the small-size test has the advantages of low cost, saving manpower and material resources, and shortening the test period. Therefore, by indoor processing and assembly, a high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions is proposed to quickly master the temperature, deformation of high-speed rail ballastless track, and the temperature, moisture and frost heaving deformation state of subgrade, and to clearly define the subgrade freezing depth and the contribution degree of frost heaving deformation of each soil layer. The influence of ballastless track on the subgrade freezing characteristics can also be further analyzed.

[0032] Please refer to Figures 1-6The application provides a technical scheme: a high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions, which can simultaneously measure various data related to freezing and thawing of the high-speed rail ballastless track and the subgrade and explore the influence of the ballastless track on the freezing characteristics of the subgrade.

[0033] The ballastless track-subgrade model comprises a ballastless track structure and a subgrade structure which are proportionally reduced according to a theory, as shown in the figure. Figure 3 The ballastless track structure 11 comprises a track slab layer 15, a self-compacting concrete layer 16 and a base slab layer 17, and the track slab layer 15, the self-compacting concrete layer 16 and the base slab layer 17 are sequentially arranged from top to bottom. The ballastless track structure 11 adopts a unit block structure, that is, three track slab layers 15 and three self-compacting concrete layers 16 are connected above the base slab layer 17. The track slab layer 15, the self-compacting concrete layer 16 and the base slab layer 17 are all made of cement. The size of the track slab is 0.56m*0.25m*0.021m (length*width*height), the size of the self-compacting concrete is 0.56m*0.25m*0.01m (length*width*height), and the size of the base slab is 1.70m*0.31m*0.03m (length*width*height). One ballastless track model is arranged on the right side of the upper surface of the subgrade.

[0034] Further, the subgrade structure comprises a subbase surface layer 6, a subbase bottom layer 7 and a lower fill embankment 8, which are sequentially arranged from top to bottom. The length of the subgrade is 2.5m, the width of the upper surface is 1.34m, the height is 0.5m, and the slope toe is 1:1.5. The subgrade material is divided into three layers from top to bottom: the thickness of the subbase surface layer 6 is 0.04m, the thickness of the subbase bottom layer 7 is 0.23m, and the thickness of the lower fill embankment layer 8 is 0.23m.

[0035] The subbase surface layer 6 adopts graded gravel, and the subbase bottom layer 7 and the lower fill embankment 8 both adopt A / B group fillers. Only the ballastless track structure is arranged on the right side of the upper surface of the subgrade structure, and no ballastless track structure is arranged on the left side of the upper surface of the subgrade structure.

[0036] Further, as shown in the figure, Figure 1As shown, the programmable high-low temperature test chamber includes a test chamber body 1, a core refrigeration unit, a PLC control system 3, a test chamber door 4 and an observation window 2 arranged on the front of the test chamber body; the size of the chamber body is 6m x 3m x 3m (length x width x height), the structural design of the test chamber is a whole structure, the chamber body uses 20cm thick polyurethane foam board and superfine fiber glass as thermal insulation materials, and the volume is 37.5m 3 ; a fan and an electric heating wire are arranged at the rear end of the chamber body; the core refrigeration unit is four refrigeration compressors 12; the PLC control system 3 uses a Delta controller, the temperature control range is -60℃-80℃, the equipment running power is 55kW, and the alternating change of the simulated environment temperature is used to keep the overall error of the temperature control in the chamber at 1℃-±0.5℃.

[0037] Further, as shown in Figure 2 , the rainfall simulation device includes a water storage tank 13 outside the test chamber, a water pump, a liquid transmission pipeline 10 and a rain shower head 5; the water pump is located in the water storage tank 13 and is connected with the power source through an electromagnetic valve for controlling the rainfall amount, rainfall speed and rainfall duration of the rainfall simulation device; the water outlet 14 of the water pump is connected with the rain shower head 5 below the top of the test chamber body through the liquid transmission pipeline 10. The rain shower head can be freely telescoped, the angle and height can be adjusted according to the working condition. By adjusting the rainfall amount, rainfall speed and rainfall duration, the actual rainfall conditions in the cold region can be simulated.

[0038] In this embodiment, a 30W water pump is placed in the water storage tank 13, the water outlet 14 of the water pump is connected with the rain shower head 5 through the liquid transmission pipeline 10 with a diameter of 1.5cm to form a rainfall simulation device for controlling the rainfall, and the rainfall amount, rainfall speed and rainfall duration of the simulation device, wherein the rainfall intensity simulated by the device can be controlled at 10-150mm / h, the rainfall uniformity coefficient is kept above 80%, and the rain shower head can be freely telescoped and the position can be adjusted according to the working condition.

[0039] Further, the solar radiation simulation device is a plurality of adjustable ultraviolet lamps 9, which are arranged below the top of the test chamber body in a symmetrical and uniform manner, for simulating different solar radiation angles and radiation amount changes. The angle and height can be freely telescoped and adjusted according to the working condition, for simulating different solar radiation angles and radiation amount changes. By adjusting the solar radiation angle and radiation amount, the simulation of the non-uniform distribution of the internal temperature of the subgrade and the non-uniform frost heaving of the surface can be realized.

[0040] In this embodiment, a steel pipe that can be extended up and down can also be installed on the upper part of the test box, a universal clamp that can be adjusted by 360 degrees is installed at the end of the steel pipe, and the adjustable ultraviolet lamp 9 is fixed through the universal clamp, so that the free adjustment of the solar radiation intensity and the radiation angle can be realized. The radiation intensity simulated by the device can be controlled at 0-1500W / m 2 , and the difference in radiation intensity is less than 50W / m 2 .

[0041] Further, as shown in Figure 4 , the data acquisition and monitoring module includes a radiation sensor 18, a frost heave displacement meter 19, a temperature sensor 20, a moisture sensor 21, a laser displacement sensor 22, and a data acquisition instrument; the data acquisition instrument is connected with the radiation sensor 18, the frost heave displacement meter 19, the temperature sensor 20, the moisture sensor 21, and the laser displacement sensor 22, and real-time monitoring and acquisition of the deformation displacement, temperature, moisture, and radiation data of the ballastless track-subgrade are realized.

[0042] Further, the temperature sensor 20 is arranged inside the ballastless track structure and the subgrade structure, and is used to acquire the temperature change inside the ballastless track and the subgrade, as shown in Figure 4 , Figure 5 , the specific arrangement includes: 1) the temperature sensor 20 is arranged symmetrically along the center of the cross section of the subgrade structure, the center of the bottom plate layer of the ballastless track, the lower part of the subgrade, and the left side, and is arranged starting from 0.02m below the top surface of the subgrade structure, and the vertical spacing from top to bottom is 0.1m, and there are a total of 15, so as to monitor the horizontal and vertical temperature change law of the subgrade structure during freezing; 2) the temperature sensor 20 is arranged vertically along the center of the ballastless track, and there are a total of 3; among them, 2 are placed on the upper surface of the track plate layer and the middle part of the track plate layer, and 1 is placed in the middle part of the bottom plate layer, so as to monitor the temperature change law at different vertical positions of the ballastless track structure during freezing.

[0043] Further, the moisture sensor 21 is arranged inside the subgrade structure, and is used to acquire the moisture change inside the subgrade; as shown in Figure 4 , Figure 6 , the moisture sensor 21 is arranged symmetrically along the center of the cross section of the subgrade structure, the center of the bottom plate layer of the ballastless track, the lower part of the subgrade, and the left side, and is arranged starting from 0.04m below the top surface of the subgrade structure, and the vertical spacing from top to bottom is 0.1m, and there are a total of 15, so as to monitor the horizontal and vertical temperature change law of the subgrade structure during freezing.

[0044] Further, the frost heave displacement meter 19 is arranged inside the subgrade structure, and is used to acquire the frost heave deformation at different depths inside the subgrade; as shown in Figure 4 , Figure 6As shown, the frost heaving displacement meter 19 is arranged at the center of the roadbed and the center of the left side of the roadbed, and a total of 2 are arranged to monitor the frost heaving deformation change law of the soil at different depths of the roadbed during the freezing process.

[0045] The laser displacement sensor 22 is arranged on the laser displacement sensor clamping device 23 on the left and right sides inside the test box body 1, and a total of 3 are arranged, and the angle and height position of the laser displacement sensor 22 are adjusted freely through the laser displacement sensor clamping device 23, so that the frost heaving deformation law of the left and right sides of the slope of the ballastless track and the roadbed can be monitored.

[0046] The radiation sensor 18 is arranged on the surface of the roadbed structure at the center and the left and right sides of the slope of the roadbed, and a total of 3 are arranged, and is used for monitoring the change law of the radiation received by the surface of the roadbed.

[0047] When the high-speed rail ballastless track-roadbed freezing characteristic simulation test device based on the meteorological conditions in the cold region is used for simulation test in the embodiment of the application, the following steps are included:

[0048] After the test preparation work is completed, the core refrigeration unit composed of a plurality of refrigeration compressors 12, the PLC control system 3 and the data acquisition and monitoring module are started, and whether the core refrigeration unit and the data acquisition and monitoring module are in a normal working state is tested, a function is fitted according to the typical air temperature in the severe cold region and is input into the PLC control system 3, so that the temperature in the test box body 1 is consistent with the actual situation on the spot;

[0049] The change of the temperature in the test box body 1 is controlled through the PLC control system 3 to realize the freezing and thawing process of the ballastless track and the roadbed structure under the low-temperature environment, and the temperature, deformation of the ballastless track and the temperature, moisture and frost heaving deformation of the roadbed are monitored in real time through the data acquisition and monitoring module;

[0050] The rainfall simulation device and the solar radiation simulation device are started, a proper amount of tap water is added into the water storage tank 13, the water pump and the rain shower nozzle 5 are opened, the rainfall simulation is carried out according to the required rainfall working condition, the adjustable ultraviolet lamp 9 is opened, the irradiation position of the ultraviolet lamp is adjusted, and whether the radiation angle and the radiation amount meet the requirements are determined through the radiation sensor 18; the test process is observed through the observation window 2 on the test box body 1, and the test process is photographed and recorded.

[0051] Through various data collected by the data acquisition instrument, the freezing depth of the roadbed and the contribution degree of the frost heaving deformation of each soil layer are determined, and the influence of the track structure on the upper part of the roadbed on the temperature and the frost heaving deformation of the roadbed structure is compared and analyzed.

[0052] The test time is determined through the scale theory. Based on the similarity theory, p and m can be used to represent the physical quantities corresponding to the prototype and the model in the similar phenomenon:

[0053] (π1) p= (pi) m = (pi) p = (pi) m

[0054]

[0055] Therefore, the similarity criterion is obtained as follows:

[0056] In the formula, c is a similarity constant, l is a geometric size, a is a thermal diffusivity, lambda is a thermal conductivity, t is a temperature, Q is a latent heat of water per unit volume, and tau is a time.

[0057] Of the six similarity constants of the similarity criterion, four similarity constants can be arbitrarily selected (basic constants), and the remaining two are obtained by similarity theory.

[0058] The soil sample selected in the test is basically consistent with the field, and therefore: c a = c Q = c λ = 1.

[0059] The temperature set in the test is consistent with the field measured temperature, and therefore: c t = 1.

[0060] In order to simulate the field observation field measured results, there are Therefore, the time scale is only related to the geometric scale, that is, the time scale is equal to the square of the geometric scale.

[0061] The geometric scale used in the embodiment is 1:10, and therefore the time scale is 1:100, that is, 87.6 hours in the test represent 365 days in reality. In the embodiment, two freeze-thaw cycle tests are performed. Through the present application, real-time monitoring of temperature, deformation and related parameters of roadbed temperature, moisture and deformation of high-speed rail ballastless track in cold regions can be realized, the frozen depth of the roadbed and the contribution of the deformation of each soil layer are determined, and the influence of the ballastless track on the freezing characteristics of the roadbed structure can also be compared and analyzed.

[0062] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or equivalently replace part of the technical features, as long as the modifications, equivalent replacements, improvements, etc. are within the spirit and principles of the present application, and should be included in the protection scope of the present application.

Claims

1. A high-speed rail ballastless track-subgrade freezing characteristic simulation test device based on meteorological conditions in cold regions, characterized in that, The device comprises a programmable high-low temperature test box for controlling the alternating change of environmental temperature, a rainfall simulation device for adjusting according to different rainfall in cold regions, a solar radiation simulation device for adjusting according to different light in cold regions, a ballastless track structure composed of unit blocks, a subgrade structure composed of three layers, and a data acquisition and monitoring module for monitoring and collecting deformation displacement, temperature, moisture and radiation data in real time. The ballastless track structure (11) comprises a track slab layer (15), a self-compacting concrete layer (16) and a base plate layer (17); the ballastless track structure (11) adopts a unit block structure, that is, three track slab layers (15) and three self-compacting concrete layers (16) are connected above the base plate layer (17); the track slab layer (15), the self-compacting concrete layer (16) and the base plate layer (17) are all made of cement. The subgrade structure comprises a subgrade surface layer (6), a subgrade bottom layer (7) and a lower fill embankment (8); the subgrade surface layer (6) adopts graded gravel, and the subgrade bottom layer (7) and the lower fill embankment (8) both adopt A / B group fillers; only the ballastless track structure is laid on the right side of the upper surface of the subgrade structure, and no ballastless track structure is laid on the left side of the upper surface of the subgrade structure. The programmable high-low temperature test box comprises a test box body (1), a core refrigeration unit, a PLC control system (3), a test box door (4) and an observation window (2) arranged on the front of the test box body, a fan and an electric heating wire arranged at the rear end of the box body; the core refrigeration unit is a plurality of refrigeration compressors (12); the PLC control system (3) adopts a Delta controller, the temperature control range is -60℃-80℃, the equipment operating power is 55kW, and the alternating change of the simulated environmental temperature is controlled, and the overall error of the temperature control in the box is kept at 1℃-±0.5℃; The solar radiation simulation device is a plurality of adjustable ultraviolet lamps (9) arranged symmetrically and uniformly on the top of the test box body, for simulating different solar radiation angles and radiation changes.

2. The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 1, characterized in that: The rainfall simulation device comprises a water storage tank (13) outside the test box, a water pump, a liquid transmission pipeline (10) and a rain shower nozzle (5); the water pump is located in the water storage tank (13) and is connected with the power supply through a solenoid valve, for controlling the rainfall amount, rainfall speed and rainfall duration of the rainfall simulation device; the water outlet (14) of the water pump is connected with the rain shower nozzle (5) below the top of the test box body through the liquid transmission pipeline (10). 3.The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 1, characterized in that: The data acquisition and monitoring module comprises a radiation sensor (18), a frost heaving displacement meter (19), a temperature sensor (20), a moisture sensor (21), a laser displacement sensor (22) and a data acquisition instrument; the data acquisition instrument is connected with the radiation sensor (18), the frost heaving displacement meter (19), the temperature sensor (20), the moisture sensor (21) and the laser displacement sensor (22) to monitor and collect the deformation displacement, temperature, moisture and radiation data of the ballastless track-subgrade in real time.

4. The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 3, characterized in that: The radiation sensor (18) is arranged on the center of the upper surface of the roadbed structure and the left and right side slopes of the roadbed structure, and a total of three radiation sensors are arranged to monitor the variation of the radiation received by the roadbed surface.

5. The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 3, characterized in that: The frost heaving displacement meter (19) is arranged inside the roadbed structure to collect the frost heaving deformation of the soil at different depths inside the roadbed structure; the frost heaving displacement meter (19) is arranged at the center of the roadbed structure and the left center of the roadbed structure, and a total of two frost heaving displacement meters are arranged to monitor the variation of the frost heaving deformation of the soil at different depths in the roadbed structure during the freezing process. 6.The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 3, characterized in that: The temperature sensor (20) is arranged inside the ballastless track structure and the roadbed structure to collect the temperature variation inside the ballastless track structure and the roadbed structure; the temperature sensor (20) is arranged at the center of the cross section of the roadbed structure, the center of the bottom plate layer of the ballastless track structure, the lower part of the roadbed structure and the symmetric position on the left side of the roadbed structure, and a total of 15 temperature sensors are arranged from the top surface of the roadbed structure to the position 0.02 m below the top surface, and the vertical spacing from top to bottom is 0.1 m, so as to monitor the horizontal and vertical temperature variation of the roadbed structure during the freezing process; the temperature sensor (20) is vertically arranged along the center of the ballastless track structure, and a total of three temperature sensors are arranged; two temperature sensors are arranged on the upper surface of the track plate layer and the middle part of the track plate layer, and one temperature sensor is arranged in the middle part of the bottom plate layer, so as to monitor the temperature variation at different positions along the vertical direction of the ballastless track structure during the freezing process.

7. The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 3, characterized in that: The moisture sensor (21) is arranged inside the roadbed structure to collect the moisture variation inside the roadbed structure; the moisture sensor (21) is arranged at the center of the cross section of the roadbed structure, the center of the bottom plate layer of the ballastless track structure, the lower part of the roadbed structure and the symmetric position on the left side of the roadbed structure, and a total of 15 moisture sensors are arranged from the top surface of the roadbed structure to the position 0.04 m below the top surface, and the vertical spacing from top to bottom is 0.1 m, so as to monitor the horizontal and vertical moisture variation of the roadbed structure during the freezing process.

8. The high-speed railway ballastless track-subgrade freezing characteristic simulation test device based on cold weather conditions according to claim 3, characterized in that: The laser displacement sensor (22) is arranged on the laser displacement sensor clamping device (23) on the left and right sides of the test box body (1), and a total of three laser displacement sensors are arranged; the angle and height position of the laser displacement sensor (22) are adjusted freely through the laser displacement sensor clamping device (23), so as to monitor the frost heaving deformation of the left and right side slopes of the ballastless track structure and the roadbed structure.

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