Multifunctional experimental system for road engineering in extreme environment

Abstract

The invention provides an extreme environment road engineering multifunctional experiment system. The extreme environment road engineering multifunctional experiment system comprises a model box, a loading assembly, a first temperature control system, a second temperature control system, a water supplementing system, a to-be-tested road assembly, a bottom heat preservation plate, a rainfall system, a lighting system, an air control system and an ultraviolet system. According to the invention, the experiment system is mainly used for testing the service performance of a road structure in extreme environments (including a plateau frozen soil environment and a coastal humid and hot environment); through the joint effect of each structure, the experimental system can realize precise control of environmental factors such as temperature, humidity, wind, rain, ultraviolet and the like, can accurately simulate extreme environments such as real plateau frozen soil and coastal damp and hot environments and various traffic loads, and can obtain road structure service state data in real time; and a solid foundation is provided for related researches on a deterioration damage disaster-causing mechanism, service life prediction and service toughness improvement of a road structure in an extreme environment.

Description

Technical Field

[0001] The invention belongs to the technical field of extreme environment road engineering, and in particular relates to a multifunctional experimental system for extreme environment road engineering. Background Art

[0002] The permafrost area of ​​the Qinghai-Tibet Plateau has a harsh environment, with high temperature, high ice content and extremely unstable permafrost accounting for a large proportion, reaching more than 50%. In addition, the climate in the region is changeable, freeze-thaw is frequent, radiation is strong, and the temperature difference between day and night is large, making the permafrost in the region extremely sensitive to road engineering disturbances, and thaw settlement and other diseases occur frequently; the high temperature and humidity, heavy rain and strong wind, strong corrosion environment in the coastal area, plus heavy loads, fatigue, and extreme disasters, make coastal road engineering diseases frequent, and collapse accidents occur frequently. The coupling effect of these extremely harsh environments and fatigue and heavy loads has reduced the service toughness of road structures, shortened their service life, and caused frequent disasters, which seriously threatened driving safety. Therefore, it is necessary to carry out research on road performance under the coupling of extreme environments and loads to improve the engineering construction and maintenance, safety toughness, service life, intelligence and greening of road structures.

[0003] The Chinese patent with application number 202310386318.7 discloses a visualization model box for roadbed filling compaction performance and load transfer experiment, which relates to the technical field of road engineering roadbed similarity test, and solves the problem that the existing conventional physical and mechanical tests have great limitations and cannot accurately show the performance of the actual filled roadbed, and the paving experiment will consume a lot of manpower and material costs. The model box includes a base, a horizontal electric slide rail, an electric slider 1, a vertical plate, a vertical electric slide rail, an electric slider 2, a model box, a servo motor, a frame, a micro motor, a screw rod, a collar, a guide rod, a rotating rod, a pressure device, an arc frame, a limit slot, a limit sleeve, a block, a limit block, a vertical frame, a slide plate, a horizontal plate, a first limit rod, a first spring, and a rotating plate; it has the characteristics of convenient and flexible experimental verification of the compaction performance and load transfer of the roadbed filling, and flexible adjustment and monitoring, and convenient and flexible installation and use;

[0004] However, in the prior art, the experimental system cannot simulate a variety of extreme environments, making it inconvenient to conduct experiments on roads in a variety of extreme environments, thereby reducing the functionality and experimental effect of the experimental system.

[0005] Therefore, it is very necessary to invent a multifunctional experimental system for road engineering in extreme environments. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a multifunctional experimental system for extreme environment road engineering to solve the problem in the prior art that the experimental system cannot simulate a variety of extreme environments, is not convenient for conducting experiments on roads in a variety of extreme environments, and reduces the functionality and experimental effect of the experimental system.

[0007] To this end, the present invention provides a multifunctional experimental system for road engineering in extreme environments, including a model box, a loading component, a first temperature control system, a second temperature control system, a water replenishment system, a road component to be tested, a bottom insulation board, a precipitation system, a lighting system, a wind control system and an ultraviolet system, wherein the bottom insulation board is installed on the lower side of the interior of the model box, and an installation groove is provided on the upper side of the bottom insulation board; the second temperature control system is installed on the lower side of the interior of the installation groove; the water replenishment system is installed above the second temperature control system; the road component to be tested is placed above the water replenishment system; the precipitation system is installed at the middle position of the upper side of the interior of the model box; the first temperature control system is installed at both ends of the upper side of the interior of the model box; the lighting system is installed on the upper side of the interior of the model box, and the lighting system is located between the first temperature control system and the precipitation system; the ultraviolet system is installed on the upper side of the interior of the model box, and the ultraviolet system is located between the precipitation system and the lighting system; the wind control system is installed on both sides of the interior of the model box; the loading component is installed on the outer side of the model box, and the end of the loading component is located above the road component to be tested;

[0008] The loading assembly includes a mounting support, a power system, a fixed plate, a transmission assembly and a loading trolley. The mounting support is mounted on the outside of the model box; the power system is mounted on the end of the mounting support facing away from the model box; the fixed plate is mounted on the end of the mounting support close to the model box; the loading trolley is arranged above the road assembly to be tested; one end of the transmission assembly is mounted on the output end of the power system, and the other end of the transmission assembly is mounted on the loading trolley, and the middle position of the transmission assembly is slidably matched with the fixed plate.

[0009] Furthermore, the multifunctional experimental system for road engineering in extreme environments includes a Fomax wheel, an electric control cabinet and a PLC controller. There are multiple Fomax wheels, and the Fomax wheels are installed at the four corners below the bottom insulation board. After moving to the position, the Fomax wheels are rotated to fix the experimental system on the ground; the electric control cabinet is connected to the mains for power supply; and the PLC controller is powered on to control the system.

[0010] Furthermore, the road component to be tested includes foundation soil, road base layer, pavement base layer and pavement asphalt layer, and the foundation soil is placed above the water replenishment system; the road base layer, pavement base layer and pavement asphalt layer are arranged above the foundation soil, and the foundation soil, road base layer, pavement base layer and pavement asphalt layer are arranged in sequence from bottom to top; the model box is made of stainless steel plates and plexiglass plates, with an observation window, an inner lining of an insulation board, and the four sides and the top plate of the model box are detachable and fixed with bolts.

[0011] Furthermore, the power system includes an external motor, a reducer, a frequency converter and a controller; a displacement sensor is installed on the loading trolley, and the displacement sensor collects the motion data of the loading trolley and transmits it to the motion controller in real time, thereby controlling the speed of the external motor to control the speed of the loading trolley. The loading trolley simulates different axle weights by adding weights, and the weights are fixed to the loading trolley with screws. The axle weight is adjusted in the range of 10 to 100 kg according to experimental requirements; the first temperature control system uses a fin tube heat exchanger, a high and low temperature integrated machine and an air cooler to control the ambient temperature. The temperature control range is -30°C to 60°C, and the temperature control accuracy is ±0.1°C. The fin tube heat exchanger is installed on the side wall of the model box and is connected to the high and low temperature integrated machine outside the model box. A temperature sensor is installed inside the model box. The temperature controller controls the temperature inside the model box in a closed loop by controlling the heat generated by the heating tube of the high and low temperature integrated machine through PID. An air cooler is installed behind the fin tube heat exchanger to accelerate heat exchange and make the temperature inside the model box more uniform.

[0012] Furthermore, the second temperature control system controls the bottom plate temperature by circulating the cold bath liquid, the temperature control range is -20℃~40℃, and the temperature control accuracy is ±0.1℃; the water replenishment system uses a water replenishment temperature control bearing plate to simulate the groundwater replenishment of the road structure. The water replenishment temperature control bearing plate is made of three layers of aluminum alloy, which can transfer the temperature to the road component to be tested faster. A groove is engraved between the bottom layer and the middle layer for the circulation of the cold bath liquid of the cold bath circulator to control the bottom plate temperature. A groove is engraved between the middle layer and the upper layer for uniform water replenishment, which is connected to a constant pressure head controller to provide It provides constant pressure water replenishment. Most of the three layers are solid structures and can withstand relatively large stress. There are sealing rings between each layer to ensure the sealing of antifreeze and water replenishment. The precipitation system sets a precipitation device in the area where the road components are to be tested. The rainfall intensity ranges from 100 to 1500 mm / h, simulating the damage of heavy rain in the coastal environment to the road components to be tested. The wind control system has a wind speed of 5 to 25 m / s, simulating the damage of typhoons in the coastal environment to the road components to be tested. The ultraviolet intensity of the ultraviolet system is 3 to 5 levels, simulating the damage of strong radiation in the plateau environment to the road structure.

[0013] Furthermore, a monitoring and acquisition system is also provided inside the model box, and the monitoring and acquisition system includes a heat flux sensor, a temperature sensor, an ice content sensor, a water content sensor, a distributed optical fiber, a high-resolution linear array camera, and a wireless transmission system to achieve real-time monitoring and acquisition of temperature, humidity, force, and deformation; and is equipped with a remote monitoring system to observe the road status in real time.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The experimental system of the present invention is mainly used to test the service performance of road structures under extreme environments (including plateau frozen soil environments and coastal hot and humid environments), including bearing capacity and durability. The experimental system consists of a loading component, a first temperature control system, a second temperature control system, a water replenishment system, a road component to be tested, a precipitation system, a lighting system, a wind control system and an ultraviolet system. Through the combined action of each structure, the experimental system can achieve precise control of environmental factors such as temperature, humidity, wind, rain, and ultraviolet rays, and can accurately simulate real plateau frozen soil, coastal hot and humid environments and various traffic loads, and obtain road structure service status data in real time, providing a solid foundation for related research on the degradation damage disaster mechanism, service life prediction, and service toughness improvement of road structures in extreme environments.

[0016] 2. The present invention adopts a loading assembly for loading, and simulates different axle weights by adding weights. The weights are fixed in the loading trolley with screws, and the axle weight is adjusted in the range of 10 to 100 kg according to the experimental requirements; the loading trolley is driven to move by the movement of an external motor, a reducer and a frequency converter, and can complete up to 3 back and forth movements on the road component to be tested within 1 second; the motion data is collected by a displacement sensor and transmitted to the motion controller in real time, so as to control the speed of the external motor to control the speed of the loading trolley; the loading assembly can simulate vehicles with different axle weights and different speeds rolling over the road structure, and can record the motion data in real time;

[0017] 3. The experimental system of the present invention has two sets of independently operated temperature control devices. The first temperature control system uses a finned tube heat exchanger, a high and low temperature integrated machine and an air cooler to control the ambient temperature. The temperature control range is -30℃~60℃, and the temperature control accuracy is ±0.1℃. The second temperature control system uses a cold bath circulation machine to control the bottom plate temperature. The temperature control range is -20℃~40℃, and the temperature control accuracy is ±0.1℃. The finned tube heat exchanger is installed on the side wall of the model box and connected to the high and low temperature integrated machine outside the model box. A temperature sensor is installed inside the model box. The temperature control The device controls the temperature in the model box in a closed loop by controlling the heat generated by the heating tube of the high and low temperature integrated machine through PID. An air cooler is installed behind the finned tube heat exchanger to accelerate heat exchange and make the temperature in the model box more uniform. The cold bath circulation machine is connected to the groove of the bottom plate, and the bottom plate temperature is controlled by circulating the cold bath liquid. The first temperature control system and the second temperature control system can simulate the temperature changes of the extreme environment outside the road structure (plateau frozen soil environment, coastal humid and hot environment), and can also simulate the temperature changes of the foundation under the road structure, which is more accurate and in line with reality.

[0018] 4. In the present invention, the water replenishment system adopts a water replenishment temperature control bearing plate to simulate the replenishment of groundwater to the road structure; the water replenishment temperature control bearing plate is made of three layers of aluminum alloy, which can transfer the temperature to the structure to be tested more quickly; a groove is engraved between the bottom layer and the middle layer for the circulation of the cold bath liquid of the cold bath circulator to control the temperature of the bottom plate; a groove is engraved between the middle layer and the upper layer for uniform water replenishment, connecting a constant pressure head controller to provide constant pressure water replenishment; most of the three layers are solid structures that can withstand relatively large stress, and there are sealing rings between each layer to ensure the sealing of the antifreeze and water replenishment; the water replenishment temperature control bearing plate has the functions of water replenishment, temperature control, and load bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention.

[0020] Figure 2 It is a schematic diagram of the structure inside the model box of the present invention.

[0021] Figure 3 It is a structural schematic diagram of the loading component of the present invention.

[0022] Figure 4 It is a schematic structural diagram of the fixing assembly of the present invention.

[0023] In the figure:

[0024] 1. Model box; 2. Loading assembly; 21. Mounting support; 22. Power system; 23. Fixed plate; 24. Transmission assembly; 25. Loading trolley; 3. First temperature control system; 4. Second temperature control assembly; 5. Water supply system; 6. Road assembly to be tested; 61. Foundation soil; 62. Road base layer; 63. Pavement base layer; 64. Pavement asphalt layer; 7. Bottom insulation board; 8. Precipitation system; 9. Lighting system; 10. Fomar wheel; 11. Wind control system; 12. UV system. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings:

[0026] Example:

[0027] As attached Figure 1 To Attachment Figure 4 Shown

[0028] The present invention provides a multifunctional experimental system for road engineering in extreme environments, comprising a model box 1, a loading component 2, a first temperature control system 3, a second temperature control system 4, a water replenishment system 5, a road component to be tested 6, a bottom insulation board 7, a precipitation system 8, a lighting system 9, a wind control system 11 and an ultraviolet system 12, wherein the bottom insulation board 7 is installed at the lower side of the interior of the model box 1, and an installation groove is provided at the upper side of the bottom insulation board 7; the second temperature control system 4 is installed at the lower side of the interior of the installation groove; the water replenishment system 5 is installed above the temperature control system 4; the road component to be tested 6 is placed at the bottom of the water replenishment system 5 The precipitation system 8 is installed at the middle position of the upper side of the model box 1; the first temperature control system 3 is installed at both ends of the upper side of the model box 1; the lighting system 9 is installed at the upper side of the model box 1, and the lighting system 9 is located between the first temperature control system 3 and the precipitation system 8; the ultraviolet system 12 is installed at the upper side of the model box 1, and the ultraviolet system 12 is located between the precipitation system 8 and the lighting system 9; the wind control system 11 is installed on both sides of the model box 1; the loading component 2 is installed on the outside of the model box 1, and the end of the loading component 2 is located above the road component 6 to be tested;

[0029] In this embodiment, the loading component 2 includes a mounting support 21, a power system 22, a fixed plate 23, a transmission component 24 and a loading cart 25. The mounting support 21 is installed on the outside of the model box 1; the power system 22 is installed on the end of the mounting support 21 away from the model box 1; the fixed plate 23 is installed on the end of the mounting support 21 close to the model box 1; the loading cart 25 is arranged above the road component 6 to be tested; one end of the transmission component 24 is installed at the output end of the power system 22, and the other end of the transmission component 24 is installed on the loading cart 25, and the middle position of the transmission component 24 is slidably matched with the fixed plate 23.

[0030] In this embodiment, the multifunctional experimental system for road engineering in extreme environments also includes a Fomag wheel 10, an electric control cabinet and a PLC controller. A plurality of Fomag wheels 10 are used, and the Fomag wheels 10 are installed at the four corners below the bottom insulation plate 7. After moving to the position, the Fomag wheel 10 is rotated to fix the experimental system on the ground; the electric control cabinet is connected to the mains for power supply; and the PLC controller is powered on to control the system.

[0031] In this embodiment, the road component 6 to be tested includes a foundation soil 61, a road base layer 62, a pavement base layer 63 and a pavement asphalt layer 64. The foundation soil 61 is placed above the water replenishment system 5; the road base layer 62, the pavement base layer 63 and the pavement asphalt layer 64 are arranged above the foundation soil 61, and the foundation soil 61, the road base layer 62, the pavement base layer 63 and the pavement asphalt layer 64 are arranged in sequence from bottom to top.

[0032] In this embodiment, the model box 1 is made of stainless steel plate and organic glass plate, with an observation window, and the inner lining is an insulation board. The four sides and the top plate of the model box 1 are detachable and fixed with bolts. The power system 22 includes an external motor, a reducer, a frequency converter and a controller. A displacement sensor is installed on the loading trolley 25, and the displacement sensor collects the motion data of the loading trolley 25 and transmits it to the motion controller in real time, so as to control the speed of the external motor to control the speed of the loading trolley 25. The loading trolley 25 simulates different axle weights by adding weights, and the weights are fixed to the loading trolley 25 with screws. The axle weight is adjusted in the range of 10 to 100 kg according to the experimental requirements; the first temperature control system 3 uses a finned tube heat exchanger, a high and low temperature integrated machine and an air cooler to control the ambient temperature. The temperature control range is -30°C to 60°C, and the temperature control accuracy is ±0.1°C. The finned tube heat exchanger is installed on the side wall of the model box 1 and is connected to the high and low temperature integrated machine outside the model box 1. A temperature sensor is installed inside the model box 1. The temperature controller controls the heating tube heat generation of the high and low temperature integrated machine through PID to close the loop and control the temperature inside the model box. An air cooler is installed behind the finned tube heat exchanger to accelerate heat exchange and make the temperature inside the model box 1 more uniform.

[0033] In this embodiment, the second temperature control system 4 controls the bottom plate temperature by circulating the cold bath liquid, the temperature control range is -20℃~40℃, and the temperature control accuracy is ±0.1℃; the water replenishment system 5 uses a water replenishment temperature control bearing plate to simulate the replenishment of groundwater to the road structure. The water replenishment temperature control bearing plate is made of three layers of aluminum alloy, which can transfer the temperature to the road component 6 to be tested faster. A groove is engraved between the bottom layer and the middle layer for the circulation of the cold bath liquid of the cold bath circulator to control the bottom plate temperature. A groove is engraved between the middle layer and the upper layer for uniform water replenishment, which is connected to a constant pressure head controller to provide Constant pressure water replenishment, most of the three layers are solid structures, which can withstand relatively large stress, and there are sealing rings between each layer to ensure the sealing of antifreeze and water replenishment; the precipitation system 8 is set with a precipitation device in the area of ​​the road component 6 to be tested, and the rainfall intensity range is 100-1500mm / h, simulating the damage of the coastal environment rainstorm to the road component 6 to be tested; the wind control system 11 has a wind speed of 5-25m / s, simulating the damage of the coastal environment typhoon to the road component 6 to be tested; the ultraviolet intensity of the ultraviolet system 12 is 3-5 levels, simulating the damage of the road structure to the strong radiation of the plateau environment;

[0034] In this embodiment, a monitoring and acquisition system is also provided inside the model box 1, and the monitoring and acquisition system includes a heat flux sensor, a temperature sensor, an ice content sensor, a water content sensor, a distributed optical fiber, a high-resolution linear array camera, and a wireless transmission system to achieve real-time monitoring and acquisition of temperature, humidity, force, and deformation; and is equipped with a remote monitoring system to observe the road status in real time.

[0035] How it works

[0036] In the present invention, the experimental system is mainly used to test the service performance of road structures under extreme environments (including plateau frozen soil environments and coastal hot and humid environments), including bearing capacity and durability. The experimental system consists of a model box 1, a loading component 2, a first temperature control system 3, a second temperature control system 4, a water replenishment system 5, a road component to be tested 6, a precipitation system 8, a lighting system 9, a wind control system 11 and an ultraviolet system 12. Through the combined action of each structure, the experimental system can achieve precise control of environmental factors such as temperature, humidity, wind, rain, and ultraviolet rays, and can accurately simulate real plateau frozen soil, coastal hot and humid environments and various traffic loads, and obtain road structure service status data in real time, providing a solid foundation for related research on the degradation damage disaster mechanism, service life prediction, and service toughness improvement of road structures in extreme environments.

[0037] The loading component 2 is used for loading. Different axle weights are simulated by adding weights. The weights are fixed to the loading trolley 25 with screws. The axle weight can be adjusted in the range of 10 to 100 kg according to the experimental requirements. The loading trolley 25 is driven by the external motor, reducer and inverter. It can complete up to 3 round trips on the road component 6 to be tested within 1 second. The displacement sensor is used to collect motion data and transmit it to the motion controller in real time, so as to control the speed of the external motor and the speed of the loading trolley 25. The loading component 2 can simulate vehicles with different axle weights and different speeds rolling over the road structure, and can record the motion data in real time.

[0038] The experimental system has two sets of independently operated temperature control devices. The first temperature control system 3 uses a finned tube heat exchanger, a high and low temperature integrated machine and an air cooler to control the ambient temperature. The temperature control range is -30℃~60℃, and the temperature control accuracy is ±0.1℃. The second temperature control system 4 uses a cold bath circulation machine to control the bottom plate temperature. The temperature control range is -20℃~40℃, and the temperature control accuracy is ±0.1℃. The finned tube heat exchanger is installed on the side wall of the model box and connected to the high and low temperature integrated machine outside the model box. A temperature sensor is installed inside the model box. The temperature controller is controlled by The PID controls the heating tube heat of the high and low temperature integrated machine to control the temperature in the model box in a closed loop. An air cooler is installed behind the finned tube heat exchanger to accelerate heat exchange and make the temperature in the model box more uniform. The cold bath circulation machine is connected to the bottom plate groove to control the bottom plate temperature through the circulation of cold bath liquid. The first temperature control system 3 and the second temperature control system 4 can simulate the temperature changes of the extreme environment outside the road structure (plateau frozen soil environment, coastal humid and hot environment) and the temperature changes of the foundation under the road structure, which is more accurate and in line with reality.

[0039] The water replenishment system 5 uses a water replenishment temperature control bearing plate to simulate the replenishment of groundwater to the road structure; the water replenishment temperature control bearing plate is made of three layers of aluminum alloy, which can transfer the temperature to the structure to be tested more quickly; grooves are engraved between the bottom layer and the middle layer for the circulation of the cold bath liquid of the cold bath circulator to control the temperature of the bottom plate; grooves are engraved between the middle layer and the upper layer for uniform water replenishment, connecting the constant pressure head controller to provide constant pressure water replenishment; most of the three layers are solid structures that can withstand relatively large stress, and there are sealing rings between each layer to ensure the sealing of the antifreeze and water replenishment; the water replenishment temperature control bearing plate has the functions of water replenishment, temperature control, and load bearing.

[0040] Utilizing the technical solution of the present invention, or those skilled in the art designing similar technical solutions inspired by the technical solution of the present invention to achieve the above-mentioned technical effects, all fall within the protection scope of the present invention.

Claims

1. A multifunctional experimental system for road engineering in extreme environments, characterized by: The invention comprises a model box (1), a loading component (2), a first temperature control system (3), a second temperature control system (4), a water replenishment system (5), a road component to be tested (6), a bottom insulation board (7), a precipitation system (8), a lighting system (9), a wind control system (11) and an ultraviolet system (12), wherein the bottom insulation board (7) is installed on the lower side of the interior of the model box (1), and an installation groove is provided on the upper side of the bottom insulation board (7); the second temperature control system (4) is installed on the lower side of the interior of the installation groove; the water replenishment system (5) is installed above the second temperature control system (4); the road component to be tested (6) is placed above the water replenishment system (5); the precipitation system (8) is installed The first temperature control system (3) is installed at both ends of the upper side of the model box (1); the lighting system (9) is installed at the upper side of the model box (1), and the lighting system (9) is located between the first temperature control system (3) and the precipitation system (8); the ultraviolet system (12) is installed at the upper side of the model box (1), and the ultraviolet system (12) is located between the precipitation system (8) and the lighting system (9); the wind control system (11) is installed on both sides of the model box (1); the loading component (2) is installed on the outside of the model box (1), and the end of the loading component (2) is located above the road component (6) to be tested; The loading assembly (2) comprises a mounting support (21), a power system (22), a fixing plate (23), a transmission assembly (24) and a loading trolley (25), wherein the mounting support (21) is mounted on the outside of the model box (1); the power system (22) is mounted on an end above the mounting support (21) away from the model box (1); the fixing plate (23) is mounted on an end above the mounting support (21) close to the model box (1); the loading trolley (25) is arranged above the road assembly (6) to be tested; one end of the transmission assembly (24) is mounted on the output end of the power system (22), and the other end of the transmission assembly (24) is mounted on the loading trolley (25), and the middle position of the transmission assembly (24) is slidably matched with the fixing plate (23).

2. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: It also includes a Fomag wheel (10), an electric control cabinet and a PLC controller. The Fomag wheels (10) are used in plurality and are installed at the four corners below the bottom insulation board (7). After the Fomag wheels (10) are moved to a position, they are rotated to fix the experimental system on the ground. The electric control cabinet is connected to the mains for power supply. The PLC controller is powered on for system control.

3. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: The road component (6) to be tested comprises a foundation soil (61), a road base layer (62), a pavement base layer (63) and a pavement asphalt layer (64); the foundation soil (61) is placed above the water replenishment system (5); the road base layer (62), the pavement base layer (63) and the pavement asphalt layer (64) are arranged above the foundation soil (61), and the foundation soil (61), the road base layer (62), the pavement base layer (63) and the pavement asphalt layer (64) are arranged in sequence from bottom to top.

4. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: The model box (1) is made of stainless steel plates and organic glass plates, has an observation window, and is lined with a heat-insulating plate. The four sides and the top plate of the model box (1) are detachable and fixed with bolts.

5. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: The power system (22) includes an external motor, a speed reducer, a frequency converter and a controller; a displacement sensor is installed on the loading trolley (25), and the displacement sensor collects motion data of the loading trolley (25) and transmits it to the motion controller in real time, thereby controlling the rotation speed of the external motor to control the speed of the loading trolley (25). The loading trolley (25) simulates different axle weights by adding weights, and the weights are fixed in the loading trolley (25) with screws. The axle weight is adjusted in the range of 10 to 100 kg according to experimental requirements.

6. The multifunctional experimental system for extreme environment road engineering according to claim 1, characterized in that: The first temperature control system (3) uses a finned tube heat exchanger, a high and low temperature integrated machine and an air cooler to control the ambient temperature, with a temperature control range of -30°C to 60°C and a temperature control accuracy of ±0.1°C; the finned tube heat exchanger is installed on the side wall of the model box (1) and is connected to the high and low temperature integrated machine outside the model box (1); a temperature sensor is installed inside the model box (1); the temperature controller controls the temperature inside the model box in a closed loop by controlling the heating value of the heating tube of the high and low temperature integrated machine through PID; an air cooler is installed behind the finned tube heat exchanger to accelerate heat exchange and make the temperature inside the model box (1) more uniform.

7. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: The second temperature control system (4) controls the temperature of the bottom plate by circulating the cold bath liquid, and the temperature control range is -20°C to 40°C, and the temperature control accuracy is ±0.1°C; the water replenishment system (5) uses a water replenishment temperature control bearing plate to simulate the replenishment of groundwater to the road structure. The water replenishment temperature control bearing plate is made of three layers of aluminum alloy, which can transfer the temperature to the road component to be tested (6) more quickly. A groove is engraved between the bottom layer and the middle layer for the circulation of the cold bath liquid of the cold bath circulator to control the temperature of the bottom plate. A groove is engraved between the middle layer and the upper layer for uniform water replenishment, which is connected to a constant pressure head controller to provide constant pressure water replenishment. Most of the three layers are solid structures and can withstand relatively large stress. There are sealing rings between each layer to ensure the sealing of the antifreeze and water replenishment.

8. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: The precipitation system (8) is provided with a precipitation device in the area of ​​the road component (6) to be tested, and the rainfall intensity ranges from 100 to 1500 mm / h, simulating the damage of a coastal rainstorm to the road component (6) to be tested; the wind speed of the wind control system (11) is 5 to 25 m / s, simulating the damage of a coastal typhoon to the road component (6) to be tested; the ultraviolet intensity of the ultraviolet system (12) is 3 to 5 levels, simulating the damage of the road structure to the strong radiation in the plateau environment.

9. The multifunctional experimental system for road engineering in extreme environments as claimed in claim 1, characterized in that: The model box (1) is also provided with a monitoring and acquisition system inside, and the monitoring and acquisition system includes a heat flux sensor, a temperature sensor, an ice content sensor, a water content sensor, a distributed optical fiber, a high-resolution linear array camera, and a wireless transmission system, so as to achieve real-time monitoring and acquisition of temperature, humidity, force, and deformation; and is equipped with a remote monitoring system to observe the road status in real time.

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