A device for preventing and treating asphalt pavement diseases

Abstract

This invention relates to a dehumidification device for preventing asphalt pavement defects, comprising a dehumidification pipe, an insulation pipe, and a heat collection mechanism and a chimney pipe installed on both sides of the pavement, all buried in the soil beneath the asphalt pavement. The heat collection mechanism includes a solar collector box, the air outlet of which is connected to one end of the dehumidification pipe. The bottom of the chimney pipe is connected to the other end of the dehumidification pipe via an air inlet pipe, and the dehumidification pipe has multiple through holes. The insulation pipe is located vertically below the dehumidification pipe within the soil structure, with both ends pointing vertically upwards and connected to the air inlet pipe and the end of the dehumidification pipe facing the heat collection mechanism, respectively. This invention utilizes the "chimney" effect to create a non-uniform moisture field around the dehumidification pipe, enhancing the capillary action that migrates moisture. This allows moisture, along with air, to enter the dehumidification pipe, rapidly reducing the moisture content in the subbase and roadbed, thus ensuring stable bearing capacity and resistance to deformation in the subbase and roadbed.

Description

Technical Field

[0001] This invention relates to the field of road engineering technology, and in particular to a dehumidification device for preventing and treating asphalt pavement defects. Background Technology

[0002] Asphalt concrete pavements are characterized by poor air permeability and difficulty in moisture evaporation. Furthermore, with prolonged use, the strength of the asphalt concrete subgrade decreases, making it prone to frost heaving. Meanwhile, urban roads, especially intersections, are subjected to greater stress due to factors such as pavement structural defects, high traffic volume, high road surface temperatures, summer rainwater soaking, winter freeze-thaw cycles, and vehicle braking. This makes urban intersections highly susceptible to cracks, rutting, and subsidence, with rutting being particularly prominent. Moreover, intersections bear a heavy traffic load, and their maintenance significantly impacts traffic flow and can easily lead to traffic accidents. Therefore, preventing road intersection defects has always been a key focus in the field of road engineering.

[0003] The primary cause of structural rutting is that the stress induced by traffic loads exceeds the strength of any layer of the pavement, leading to significant cracking and deformation. Rutting formation involves an initial compaction process, an asphalt mixture flow process, and a process controlling aggregate rearrangement and failure.

[0004] The initial compaction process involves both vehicle loads compacting the asphalt mixture and the subbase and base course. Based on the actual vehicle load conditions, the load under the wheel track is relatively large. According to Hooke's Law, the wheel track experiences greater deformation compared to other areas.

[0005] The flow process of asphalt mixture is the process by which asphalt pavement undergoes flow deformation under the influence of external forces such as vehicle load and ambient temperature. With the continuous action and accumulation of external loads and temperature stress, the asphalt surface layer under the wheel track undergoes compression and deformation, eventually leading to plastic strain and causing rutting phenomena with raised deformation on both sides of the wheel track;

[0006] Controlling the rearrangement and destruction of aggregates is crucial because asphalt mixtures exist in a semi-solid form at high temperatures. Under external traffic loads, the asphalt and asphalt mastic undergo flow deformation, causing the asphalt and asphalt mastic contained in the asphalt mixture to flow towards the enrichment area. This results in the asphalt in the asphalt mixture losing its load-bearing function and causing larger cracks to occur.

[0007] Therefore, the damage to asphalt pavements is directly related to factors such as load, temperature, subgrade deformation and settlement, and cracking of the asphalt surface layer. It is also indirectly related to factors such as subbase cracking, rainwater infiltration, and capillary rise. This is because the subgrade soil generally contains a large amount of silt, which has a dense and very fine capillary structure. Groundwater rises through capillary action and affects the moisture content of the entire subgrade soil, thus significantly impacting the initial moisture field of the subgrade. Simultaneously, rainwater infiltration and capillary rise increase the moisture content of the subbase and subgrade, leading to a decrease in mechanical properties. Under repeated vehicle loads, liquefaction occurs, resulting in frost heave.

[0008] In particular, rainwater seeps into the roadbed through slopes. Due to pore water pressure, the uneven distribution of moisture content within the roadbed leads to an uneven distribution of the moisture field. Under the coupling effect of the moisture field and the stress field, stress redistribution occurs within the roadbed, causing a sharp decrease in roadbed strength, weakening its stability, and resulting in a series of roadbed and pavement defects. Besides rainwater infiltration, water in the soil migrates upwards through capillary action, temperature, and evaporation. Furthermore, the asphalt surface layer is an impermeable covering layer, hindering moisture evaporation. This causes moisture to accumulate beneath the asphalt surface layer in summer and condense beneath it in winter, leading to freeze-thaw damage and accelerating asphalt layer deterioration. Therefore, the damage to the road asphalt layer is also related to the stability of the subbase and roadbed itself.

[0009] However, existing methods for preventing and controlling road intersection defects mostly focus on asphalt pavement, using methods such as modified asphalt and admixtures to improve the high-temperature stability and fatigue resistance of the asphalt pavement, as seen in patent documents with publication numbers CN111879637A and CN206503047U. There are also research directions that improve the deformation capacity of the roadbed by designing semi-flexible asphalt pavement base structures, as seen in patent documents with publication numbers CN106587842A, CN208415027U, CN205134128U, and CN111118999A. Additionally, there are patent documents that involve installing blind drains at rutted areas or along roadsides to drain water from the roadbed, aiming to solve the problem of roadbed subsidence, as seen in patent documents with publication numbers CN202787009U and CN107217608A. However, these methods mainly focus on cracking and rutting of asphalt pavement, and take the disease phenomenon as the research point. They do not study the influence between the pavement, subbase, and roadbed. They take intuitive thinking as the starting point for solving problems, lack the theoretical foundation of mechanics and other systematic approaches, and thus produce the phenomenon that solving one disease problem leads to another disease problem. Summary of the Invention

[0010] To address the shortcomings of existing technologies, the present invention aims to provide a dehumidification device for preventing and controlling asphalt pavement diseases. Based on the "chimney" effect, the present invention creates a non-uniform moisture field around the dehumidification pipe to enhance the effect of capillary force in migrating moisture. This allows moisture to enter the dehumidification pipe along with air, thereby rapidly reducing the moisture content in the subbase and roadbed. This ensures that the subbase and roadbed have stable bearing capacity and resistance to deformation, thereby controlling pavement settlement and reducing cracking of the asphalt surface layer.

[0011] To achieve the above objectives, the present invention provides the following technical solution:

[0012] A dehumidification device for preventing asphalt pavement defects includes a dehumidification pipe, an insulation pipe, and a heat collection mechanism and a chimney pipe installed on both sides of the pavement, all buried in the soil beneath the asphalt pavement. The heat collection mechanism includes a solar collector box, the air outlet of which is connected to one end of the dehumidification pipe. The bottom of the chimney pipe is connected to the other end of the dehumidification pipe via an air inlet pipe. The dehumidification pipe has multiple through holes. The insulation pipe is located in the soil structure directly below the dehumidification pipe, with both ends pointing vertically upwards and connected to the air inlet pipe and the end of the dehumidification pipe facing the heat collection mechanism, respectively.

[0013] Preferably, the inflation tube is further provided with a blower, the air inlet of the blower is connected to the space inside the inflation tube, and the air outlet of the blower is connected to the insulation tube.

[0014] Preferably, the air outlet connection of the solar collector box is also provided with a solenoid valve, the input end of the solenoid valve and the input end of the blower are respectively connected to the output end of the humidity sensor, and the humidity sensor and the exhaust pipe are set at the same horizontal height.

[0015] Preferably, the blower and solenoid valve are powered by a battery, which is powered by a ground-mounted solar panel. The solar panel generates energy using monocrystalline silicon solar cells, which have the highest photoelectric conversion efficiency, approximately 18-24%. Based on the area of ​​the solar cells, a typical solar panel provides about 160W per square meter. Assuming 6 hours of effective sunlight per day, and deducting losses during charging, the solar panel's output power should be around 200W. This power, after charging the battery, provides power to the blower, solenoid valve, and humidity sensor.

[0016] Preferably, the chimney pipe is vertically arranged and has an overall hollow conical structure. The top of the chimney pipe is bent and positioned at a height higher than that of the solar collector. The outer wall of the top of the chimney pipe, especially the section extending above the solar collector box, is coated with a solar heat-absorbing layer. This layer absorbs heat, raising the temperature of the air inside the top of the chimney pipe. As the hot air rises and exits the chimney, this increases the chimney's suction efficiency. The bend at the top of the chimney pipe prevents rainwater from seeping into the chimney.

[0017] Preferably, the solar collector box includes a transparent outer shell and a heat-absorbing plate disposed inside the transparent outer shell. The heat-absorbing plate is integrated with heat-absorbing tubes arranged in a serpentine pattern. One end of the heat-absorbing tubes extends out of the outer shell and communicates with the outside, and the other end is connected to a dehumidification pipe. The heat-absorbing tubes and the heat-absorbing plate are coated with a light-absorbing layer, and a heat-insulating material layer is provided at the bottom of the heat-absorbing plate.

[0018] Preferably, the transparent outer shell is made of a material that allows visible light to pass through but not far-infrared rays. The transparent outer shell allows visible light to pass through but not far-infrared rays because solar collectors primarily rely on absorbing visible light to gather heat, while far-infrared rays cause energy loss. Therefore, preventing far-infrared rays from entering ensures that the energy entering the transparent outer shell from solar radiation is greater than the energy lost, thereby increasing the temperature of the heat-absorbing plate.

[0019] Preferably, the exhaust pipe is connected to the air outlet of the solar collector box via a connecting pipe, and the connecting pipe is covered with an insulation material layer. The insulation material layer is a high-density rubber and plastic pipe insulation cotton sleeve, which effectively reduces heat loss and dissipation into the surrounding environment.

[0020] Preferably, the exhaust pipes are arranged in a serpentine pattern within a horizontal plane. The pipe walls are porous, composed of fibers approximately 2mm in diameter, fused together at their joints to form a three-dimensional mesh. This mesh exhibits high surface porosity, excellent water collection, high porosity, good drainage, strong compressive strength, good pressure resistance, good flexibility, and adaptability to soil deformation. The exhaust pipes, arranged in an "S" shape within the roadbed, effectively increase the contact area with the soil beneath the roadbed, allowing for better airflow and circulation between hot air and the surrounding soil. Under atmospheric pressure, the air inside the pipes heats up, accelerating the migration of moisture in the soil. This promotes gas flow and temperature exchange, thereby reducing the soil moisture content and ensuring the roadbed's moisture content.

[0021] This invention involves burying a moisture-draining pipe beneath the roadbed. The moisture-draining pipe is connected to the outside world through an air-filled pipe and a chimney pipe, thus creating a channel for water to drain out and establishing an evaporation path for capillary water and accumulated rainwater beneath the roadbed, solving the problem of asphalt pavement obstructing evaporation.

[0022] Meanwhile, after the sunlight enters the solar collector box, its heat is absorbed by the heat absorption plate and heat absorption tube, which in turn heats the air inside the heat absorption tube. In addition, the heat absorption layer on the outer wall of the top of the chimney tube heats the air inside and rises, creating a negative pressure that generates the "chimney effect". As a result, the airflow direction in the pipes of this device is as follows: air → heat absorption tube → connecting pipe → dehumidification pipe → air filling pipe → chimney tube → outside.

[0023] During this process, the entry of hot air into the exhaust pipe raises the internal temperature of the pipe and simultaneously increases the temperature of the soil outside the pipe, accelerating moisture migration and thus speeding up the exchange of moisture between the pipe's sidewall pores and the soil. Under atmospheric pressure, a non-uniform moisture field forms within the exhaust pipe. The lower external temperature allows moisture from the surrounding soil to continuously enter the pipe and be expelled through airflow, reducing the soil moisture content outside the pipe. This also creates a chain reaction in the nearby soil: the moisture content of the soil around the exhaust pipe is lower than that of the distant soil. Under atmospheric pressure and capillary action due to soil particle adsorption, the moist soil further away continuously supplies water to the vicinity of the exhaust pipe, gradually reducing the overall soil moisture content.

[0024] When the moisture content of the subgrade soil is lower than the set standard value, the humidity sensor controls the solenoid valve to block the connection between the connecting pipe and the heat absorption pipe. At the same time, the blower is started, and the blower forms a circulating airflow: outside air → inflation pipe → insulation pipe → dehumidification pipe → inflation pipe → insulation pipe. When the gas passes through the insulation pipe, it exchanges heat with the soil deep in the subgrade: for example, in summer, the temperature of the soil deep in the subgrade is lower than that of the road surface, the air in the insulation pipe will cool down and circulate to the dehumidification pipe, cooling the road surface above the dehumidification pipe, thus preventing cracking of the asphalt surface layer and improving the durability of the asphalt surface layer; for example, in winter, the temperature of the soil deep in the subgrade is higher than that of the road surface, the air in the insulation pipe will warm up and circulate to the dehumidification pipe, warming the road surface above the dehumidification pipe, thus preventing freeze-thaw damage to the asphalt surface layer.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] 1) Based on the "chimney" effect, this invention forms an uneven moisture field around the exhaust pipe to improve the effect of capillary force in migrating moisture. This allows moisture to enter the exhaust pipe along with air, thereby rapidly reducing the moisture content in the subbase and roadbed. This ensures that the subbase and roadbed have stable bearing capacity and resistance to deformation, thereby controlling road surface settlement and reducing cracking of the asphalt surface layer.

[0027] 2) This invention can cool down the asphalt surface layer in summer and heat up the asphalt surface layer in winter, thereby preventing the asphalt surface layer from cracking due to excessive heat in summer and preventing the water under the asphalt surface layer from freezing and forming freeze-thaw damage in winter.

[0028] 3) The invention has low construction and setup costs and is easy to implement and operate. It relies on solar energy to provide a heat source and solar panels to convert light energy into electrical energy, saving a lot of energy consumption of mechanical ventilation equipment and effectively reducing pollution. It has sustainable application value. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the dehumidification device described in a specific embodiment;

[0030] Figure 2 This is a schematic diagram of the structure of the solar collector box described in a specific embodiment;

[0031] Figure 3 This is a graph showing the change in soil moisture data over a week, measured by temperature and humidity sensors B and C in a specific implementation method. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0033] like Figure 1-3 As shown, a dehumidification device for preventing asphalt pavement defects includes a dehumidification pipe 2, an insulation pipe 3, and heat collection mechanisms and chimney pipes 1 installed on both sides of the asphalt pavement.

[0034] The chimney pipe 1 is vertically arranged and has a hollow conical structure. The top of the chimney pipe 1 is bent and is set at a horizontal height higher than that of the solar collector. The top of the chimney pipe 1, especially the outer wall of the pipe body that is higher than the solar collector box, is coated with a light-absorbing layer 11.

[0035] The solar collector includes a solar collector box 4, which comprises a transparent outer shell 41 and a heat-absorbing plate 42 disposed inside the transparent outer shell 41. The transparent outer shell 41 is made of a material that allows visible light to pass through but not far-infrared rays. The heat-absorbing plate 42 has serpentine heat-absorbing tubes 43 integrated on it. The heat-absorbing tubes 43 and the heat-absorbing plate 42 are coated with a light-absorbing layer 11, and the bottom of the heat-absorbing plate 42 is provided with a heat-insulating material layer 46. One end of the heat-absorbing tube 43 extends out of the outer shell and communicates with the outside; the other end is connected to one end of a connecting pipe 45 via a solenoid valve 44. The other end of the connecting pipe 45 is connected to a dehumidification pipe 2, and the connecting pipe 45 is covered with a heat-insulating material layer 46.

[0036] The bottom of the chimney pipe 1 is connected to the other end of the exhaust pipe 2 through the air inlet pipe 12. The exhaust pipe 2 has multiple through holes 21 and is arranged in a serpentine pattern in a horizontal plane. A blower 5 is also provided inside the air inlet pipe 12.

[0037] The insulation pipe 3 is located in the soil structure below the vertical direction of the dehumidification pipe 2, and both ends of the insulation pipe 3 are vertically upward and connected to the air inlet pipe 12 and the end of the dehumidification pipe 2 facing the heat collection mechanism, respectively. The air inlet of the blower 5 is connected to the space inside the air inlet pipe 12, and the air outlet of the blower 5 is connected to the insulation pipe 3.

[0038] The input terminals of the solenoid valve 44 and the blower 5 are respectively connected to the output terminal of the humidity sensor. The humidity sensor 7 and the exhaust pipe 2 are set at the same horizontal height. The blower 5 and the solenoid valve 44 are powered by the storage battery 6, which is powered by a solar panel 61 installed on the ground.

[0039] This invention involves burying a moisture-draining pipe beneath the roadbed. The moisture-draining pipe is connected to the outside world through an air-filled pipe and a chimney pipe, thus creating a channel for water to drain out and establishing an evaporation path for capillary water and accumulated rainwater beneath the roadbed, solving the problem of asphalt pavement obstructing evaporation.

[0040] Meanwhile, after the sunlight enters the solar collector box, its heat is absorbed by the heat absorption plate and heat absorption tube, which in turn heats the air inside the heat absorption tube. In addition, the "chimney effect" generated by the heat absorption and exhaust of hot air outside the chimney tube makes the airflow direction formed in the pipe of this device as follows: air → heat absorption tube → connecting pipe → dehumidification pipe → air filling pipe → chimney tube → outside.

[0041] During this process, the entry of hot air into the exhaust pipe raises the internal temperature of the pipe and simultaneously increases the temperature of the soil outside the pipe, accelerating moisture migration and thus speeding up the exchange of moisture between the pipe's sidewall pores and the soil. Under atmospheric pressure, a non-uniform moisture field forms within the exhaust pipe. The lower external temperature allows moisture from the surrounding soil to continuously enter the pipe and be expelled through airflow, reducing the soil moisture content outside the pipe. This also creates a chain reaction in the nearby soil: the moisture content of the soil around the exhaust pipe is lower than that of the distant soil. Under atmospheric pressure and capillary action due to soil particle adsorption, the moist soil further away continuously supplies water to the vicinity of the exhaust pipe, gradually reducing the overall soil moisture content.

[0042] When the moisture content of the subgrade soil is lower than the set standard value, the humidity sensor controls the solenoid valve to block the connection between the connecting pipe and the heat absorption pipe. At the same time, the blower is started, and the blower forms a circulating airflow: outside air → inflation pipe → insulation pipe → dehumidification pipe → inflation pipe → insulation pipe. When the gas passes through the insulation pipe, it exchanges heat with the soil deep in the subgrade: for example, in summer, the temperature of the soil deep in the subgrade is lower than that of the road surface, the air in the insulation pipe will cool down and circulate to the dehumidification pipe, cooling the road surface above the dehumidification pipe, thus preventing cracking of the asphalt surface layer and improving the durability of the asphalt surface layer; for example, in winter, the temperature of the soil deep in the subgrade is higher than that of the road surface, the air in the insulation pipe will warm up and circulate to the dehumidification pipe, warming the road surface above the dehumidification pipe, thus preventing freeze-thaw damage to the asphalt surface layer.

[0043] This embodiment is specifically applied to a road intersection in a city in Henan Province, where the road surface is asphalt:

[0044] 1) The moisture content of the existing roadbed soil was measured. The original roadbed soil temperature was determined to be 39℃ and humidity to be 40%. The moisture content of the roadbed soil was determined by weighing method (the experimental instruments required for measuring the moisture content of roadbed soil are: a 105-110℃ energy drying oven and a balance with a sensitivity accurate to 0.01g. A 500g soil sample was selected and kept in the 105℃ oven for 8 hours. After drying, the soil sample was weighed, and the moisture content result was obtained using the moisture content calculation formula). The temperature was determined by a temperature measuring instrument.

[0045] 2) Install the dehumidification device described in the embodiment, and the horizontal plane where the dehumidification pipe is located is 50cm deep into the roadbed.

[0046] 3) Install a dehumidification pipe 50cm deep into the roadbed surface. Place two temperature and humidity sensors, B and C, on the same horizontal plane, with a horizontal distance of 40cm between points B and C. Point B is set to continuously record the temperature and humidity values ​​at the location of the dehumidification pipe in the roadbed, and observe the temperature and humidity changes of the dehumidification pipe and the surrounding soil. After the two temperature and humidity sensors are installed, pour water until the roadbed soil is saturated.

[0047] Sensor C is located close to the exhaust pipe, while point B is located away from the exhaust pipe. Analysis is performed using data from one week of observations (with similar weather conditions over 7 days). The analysis data is as follows: Figure 3As shown, the rate of change in soil moisture is greatest within 24 hours, and then gradually stabilizes over the next 6 days with smaller fluctuations. Observations indicate that the soil moisture content at sensor C after 7 days is significantly lower than that at sensor B. This suggests that the heat generated by the solar collector flows through the pipes and acts as a heat conductor in the roadbed soil, increasing the internal temperature and decreasing the air pressure. Simultaneously, utilizing the chimney principle, it dissipates heat from the soil, promoting the migration and evaporation of moisture in the soil surrounding the exhaust pipe. Moisture continuously flows from the surrounding soil towards areas with lower moisture content, creating a continuous cycle that reduces soil moisture.

Claims

1. A dehumidification device for preventing and controlling asphalt pavement defects, characterized in that, The wet exhaust device comprises a wet exhaust pipe, a heat preservation pipe, a heat collecting mechanism and a chimney pipe, the wet exhaust pipe is embedded in the soil under the asphalt pavement, the chimney pipe is vertically arranged and has a hollow cone structure, the top of the chimney pipe is bent and arranged at a horizontal height higher than that of the heat collecting mechanism, and the outer wall of the top of the chimney pipe is coated with a light heat absorption layer; The heat collecting mechanism comprises a solar heat collecting box, and the air outlet of the solar heat collecting box is communicated with one end of the wet exhaust pipe; The bottom of the chimney pipe is communicated with the other end of the wet exhaust pipe through an air charging pipe, a plurality of through holes are formed in the wet exhaust pipe, and a blower is further arranged in the air charging pipe, the air inlet of the blower is communicated with the space in the air charging pipe, and the air outlet of the blower is communicated with the heat preservation pipe; An electromagnetic valve is further arranged at the air outlet of the solar heat collecting box, the input end of the electromagnetic valve and the input end of the blower are respectively connected with the output end signal of a humidity sensor, and the humidity sensor is arranged at the same horizontal height as the wet exhaust pipe; The solar heat collecting box comprises a transparent shell and a heat absorption plate arranged in the transparent shell, the heat absorption plate is integrated with heat absorption pipes arranged in a serpentine shape, one end of the heat absorption pipe penetrates out of the shell and is communicated with the outside, the other end of the heat absorption pipe is connected with the wet exhaust pipe, the heat absorption pipes and the heat absorption plate are coated with a light heat absorption layer, and a heat preservation material layer is arranged at the bottom of the heat absorption plate; The heat preservation pipe is arranged in the soil structure below the wet exhaust pipe in the vertical direction, and the two ends of the heat preservation pipe are vertically upward and respectively communicated with the air charging pipe and the end of the wet exhaust pipe facing the heat collecting mechanism.

2. The moisture draining device for preventing and treating asphalt pavement diseases according to claim 1, wherein The blower and the electromagnetic valve are powered by a storage battery, and the storage battery is powered by a solar panel arranged on the ground.

3. The moisture draining device for preventing and treating asphalt pavement diseases according to claim 1, wherein The transparent shell is made of a material that can transmit visible light but cannot transmit far infrared rays.

4. The moisture draining device for preventing and treating asphalt pavement diseases according to claim 1, wherein The wet exhaust pipe is communicated with the air outlet of the solar heat collecting box through a connecting pipe, and the connecting pipe is externally wrapped with a heat preservation material layer.

5. The moisture draining device for preventing and treating asphalt pavement diseases according to claim 1, wherein The wet exhaust pipe is arranged in a serpentine shape in a horizontal plane.

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