A method for preventing and monitoring the cracking state of high-fill subgrade expressways

Abstract

The present invention provides a method for preventing, controlling and monitoring the cracking state of a high-fill subgrade expressway, which includes a semi-rigid base course, a carbon fiber board, acoustic emission sensors, a power supply and data acquisition system, and a remote processing center; the semi-rigid base course is used for layered paving; the carbon fiber board is configured as a rectangular structure with the same width as the road, and the carbon fiber board is fixed between each layer of the semi-rigid base course for strengthening the road surface base course and is laid in the extending direction of the road surface; the acoustic emission sensors are fixedly installed at one end or both ends of some or all of the carbon fiber boards; the power supply and data acquisition system is connected to each acoustic emission slave sensor for obtaining the data of the acoustic emission sensors; after receiving the data of each acoustic emission sensor, the remote processing center analyzes and judges the cracking state of the road base course at the corresponding position by judging the deformation or cracking state of each carbon fiber board. This method has the advantages of high strengthening strength for the road surface, timely monitoring of the cracking situation of the strengthened road surface and giving early warnings.

Description

Technical Field

[0001] The present invention relates to the technical field of highway monitoring and prevention, and specifically, to a method for preventing and monitoring the cracking state of high-fill subgrade highways. Background Art

[0002] With the rapid development of China's economy, the mileage of mountain highways is getting longer and longer. Due to the characteristics of high fills and deep excavations in the mountain highway subgrades, the problems of their stability and disaster prevention are very prominent. Due to local geological and hydrological conditions and other reasons, high-fill subgrades will be damaged, and in severe cases, it will lead to pavement cracking or even fracture, thus affecting the safe use of the highway.

[0003] Therefore, it is necessary to reinforce the damaged pavement. There are various ways of reinforcement, and among them, placing a reinforcement structure into the subgrade is a common practice.

[0004] However, after the reinforcement treatment, there is no way to monitor and give early warnings for the reinforced subgrade, making it difficult to timely detect whether there are situations such as pavement cracking and damage. It is still necessary to rely on special detection equipment to detect along the pavement one by one, which is highly difficult and cumbersome to operate.

[0005] Acoustic emission technology is a technology that can be used for pavement flaw detection. However, the currently developed application technologies all have defects. On the one hand, they cannot be organically combined with the reinforcement system, and on the other hand, their flaw detection requires a special structure.

[0006] For example, in the patent with the publication number: CN106836170A and the patent name: A method for detecting road base damage using acoustic emission technology, acoustic emission technology is used to detect flaws in the pavement. However, its solution requires drilling holes in the pavement, which is not conducive to pavement maintenance.

[0007] Another example is the patent with the publication number: CN110887453A and the patent name: A distributed deformation monitoring system for highway tunnels. The acoustic emission detector is located inside the tunnel, and its specific installation form is not disclosed, nor is its combined form with the reinforcement system.

[0008] Therefore, based on pavement reinforcement technology, how to use acoustic emission technology to timely detect whether there are dangerous situations such as pavement cracking after reinforcement and conduct timely maintenance is a technical problem that needs to be urgently solved by those skilled in the art.

[0009] To solve the above existing problems, people have been seeking an ideal technical solution. Summary of the Invention

[0010] The object of the present invention is to address the deficiencies of the prior art, and thus provide a method for preventing and monitoring the cracking state of high-fill subgrade expressways, which has high reinforcement strength for the road surface, can timely monitor the cracking condition of the road surface after reinforcement, and give early warnings.

[0011] To achieve the above object, the technical solution adopted by the present invention is: a method for preventing and monitoring the cracking state of high-fill subgrade expressways, including a semi-rigid base course, carbon fiber plates, acoustic emission sensors, a power supply and data acquisition system, and a remote processing center;

[0012] The semi-rigid base course is used for layered laying to form the road base course, and epoxy resin is coated between each layer of the semi-rigid base course;

[0013] The carbon fiber plates are configured as rectangular structures with the same width as the road, and the carbon fiber plates are fixed between each layer of the semi-rigid base course to reinforce the road base course, and the carbon fiber plates are laid at a set spacing along the extension direction of the road surface;

[0014] The acoustic emission sensors are fixedly installed at one end or both ends of some or all of the carbon fiber plates;

[0015] The power supply and data acquisition system is connected to each acoustic emission slave sensor to obtain the data of the acoustic emission sensors and send them to the remote end;

[0016] After receiving the data of each acoustic emission sensor, the remote processing center analyzes it, and judges the cracking state of the road base course at the corresponding position by judging the deformation or cracking state of each carbon fiber plate.

[0017] Based on the above, the basic material of the semi-rigid base course is cement stabilized macadam, and each layer of the semi-rigid base course is made by rolling cement stabilized macadam.

[0018] Based on the above, the acoustic emission sensors are fixed at the ends of the carbon fiber plates through fixators, and the carbon fiber plates where the acoustic emission sensors are fixed are thickened.

[0019] Based on the above, the carbon fiber plates are bonded to each layer of the semi-rigid base course through epoxy resin, and the thickness of the epoxy resin is 1-5 mm.

[0020] Based on the above, the carbon fiber plates are fixed to the semi-rigid base course through steel nails.

[0021] Based on the above, the acoustic emission sensors are acoustic emission sensors in a wireless transmission form.

[0022] Based on the above, the acoustic emission sensors are arranged inside the road surface base course on both sides of the road, and reserved channels are provided on both sides inside the road surface base course, and the channels are detachably filled with carbon fiber rods or steel bars.

[0023] Based on the above, the thickness after superimposing each layer of semi-rigid base is 25 - 35 cm.

[0024] Based on the above, the fixture is a fixture with an acoustic emission sensor installation groove, and the fixture is fixed in the layered area of the semi-rigid base.

[0025] The present invention has prominent substantial features and remarkable progress compared with the prior art. Specifically, the present invention has the following advantages:

[0026] 1. The roadbed structure is transformed into a structure of superimposing multiple layers of semi-rigid base, epoxy resin and carbon fiber plates. The carbon fiber plates themselves have strong structural strength and can support the roadbed structure, significantly improving the reinforcement performance of the roadbed structure.

[0027] 2. Based on the principle that the deformation or cracking of the carbon fiber plate will be caused by the cracking of the roadbed, the acoustic emission sensor is used to only detect the deformation state of the carbon fiber plate, without directly detecting the cracking situation of the roadbed, reducing the application difficulty of the acoustic emission sensor and having relatively high accuracy.

[0028] 3. Since the roadbed is a multi-layer structure and the carbon fiber plates are also laid in multiple layers, the characteristics of deformation and cracking of the roadbed structure will be quickly transmitted to each layer of carbon fiber plates, and the detection sensitivity is relatively high.

[0029] 4. The acoustic emission sensor is buried inside the roadbed and communicates with the outside wirelessly, with good road consistency and detection with the same lifespan as the road, and good timeliness. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the overall structural schematic diagram of the method for preventing and monitoring the cracking state of high-fill roadbed expressways in the present invention.

[0031] Figure 2 is the same-layer distribution diagram of the method for preventing and monitoring the cracking state of high-fill roadbed expressways in the present invention.

[0032] Figure 3 is the installation detail diagram of the acoustic emission sensor of the method for preventing and monitoring the cracking state of high-fill roadbed expressways in the present invention.

[0033] Figure 4 is the positional relationship diagram between the acoustic emission sensor and the carbon fiber plate of the method for preventing and monitoring the cracking state of high-fill roadbed expressways in the present invention.

[0034] Figure 5 is the schematic diagram of the reserved hole structure of the method for preventing and monitoring the cracking state of high-fill roadbed expressways in the present invention.

[0035] In the figure: 1. Semi-rigid base; 2. Carbon fiber plate; 3. Acoustic emission sensor; 4. Power supply and data acquisition system; 5. Fixator; 6. Carbon fiber rod. Specific implementation manner

[0036] The technical solution of the present invention will be further described in detail below through specific implementation manners.

[0037] As Figures 1 - 4 shown, a method for preventing and monitoring the cracking state of high-fill subgrade expressways includes a semi-rigid base 1, a carbon fiber plate 2, an acoustic emission sensor 3, a power supply and data acquisition system 4, and a remote processing center.

[0038] The semi-rigid base 1 is used for layered paving to form the road base. The base material is cement-stabilized macadam. Each layer of the semi-rigid base is made by rolling cement-stabilized macadam. Epoxy resin with a thickness of 1 - 5 mm is coated between each layer of the semi-rigid base 1. The epoxy resin serves as a filler and an adhesive. On the one hand, it fixes the adjacent semi-rigid bases 1, and on the other hand, it fixes the carbon fiber plate 2. The thickness of the superposed layers of the semi-rigid base is 25 - 35 cm.

[0039] The carbon fiber plate 2 is configured as a rectangular structure with the same width as the road. The carbon fiber plate 2 is fixed between each layer of the semi-rigid base 1 for strengthening the road base. The carbon fiber plate 2 is laid at a set spacing along the extension direction of the road surface. The spacing is determined according to the reinforcement requirements of the road surface. The carbon fiber plate and the semi-rigid base are fixed by steel nails.

[0040] The acoustic emission sensor 3 is fixedly installed at one end or both ends of some or all of the carbon fiber plates 2 through a fixator 5. The acoustic emission sensor is an acoustic emission sensor in a wireless transmission form, and the carbon fiber plate for fixing the acoustic emission sensor is thickened. The specific installation quantity and installation position are calculated according to the load on the road to obtain the optimal installation position of the acoustic emission sensor for real-time monitoring of the base state.

[0041] The fixator 5 is a fixator with an acoustic emission sensor installation groove. The fixator 5 is fixed in the layered area of the semi-rigid base 1.

[0042] The power supply and data acquisition system 4 is connected to each acoustic emission slave sensor to obtain the data of the acoustic emission sensor and send it to the remote end, which can be set in a one-to-one connection or a one-to-many connection manner.

[0043] After receiving the data of each acoustic emission sensor, the remote processing center analyzes it, and judges the cracking state of the road base at the corresponding position by judging the deformation or cracking state of each carbon fiber plate.

[0044] As Figure 5As shown, the acoustic emission sensor 3 is embedded inside the roadbed on both sides of the road. Reserved channels are provided on both inner sides of the roadbed, and the channels are detachably filled with carbon fiber rods 6 or steel bars.

[0045] Working principle:

[0046] The carbon fiber plates are laid in one layer or multiple layers according to the load conditions of the road. One of its main functions is to improve the bearing capacity of the roadbed. The separated setting method is adopted instead of the continuous mode to avoid damage to the carbon fiber plates caused by the normal thermal expansion and contraction of the road, which affects their performance.

[0047] In order to monitor the road conditions, while making full use of the advantages of the acoustic emission technology and minimizing the conditional limitations of the acoustic emission technology, instead of directly detecting the roadbed with the acoustic emission sensor, the acoustic emission sensor is installed on the carbon fiber plate. At the same time, according to the positions where the roadbed is prone to cracking, the installation positions and the number of installed acoustic emission sensors are optimized.

[0048] When a load is applied to the road surface, the roadbed will deform. At this time, the carbon fiber plates arranged in the roadbed will deform accordingly. The acoustic emission sensors installed at both ends of the carbon fiber plate can quickly obtain data, and the corresponding deformation data is collected through the power supply and data acquisition system 4 and sent to the remote processing center. After the remote processing center collects the monitoring data of a certain section of the road, by simulating and analyzing these deformation data, a judgment is made on the real-time state of the roadbed, such as whether it is in the micro-crack stage, the macro-crack stage or the fracture and failure stage, etc., so as to be able to timely grasp the current state, carry out further reinforcement and repair work, and avoid the occurrence of latitudes.

[0049] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: still modifications can be made to the specific implementation manners of the present invention or equivalent replacements can be made to some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A method for preventing, controlling and monitoring the cracking state of high-fill subgrade expressways, characterized in that: It includes a semi-rigid base course, a carbon fiber board, acoustic emission sensors, a power supply and data acquisition system, and a remote processing center; The semi-rigid base course is used for layered paving to form the road base course, and epoxy resin is coated between each layer of the semi-rigid base course; The carbon fiber board is configured as a rectangular structure with the same width as the road. The carbon fiber board is fixed between each layer of the semi-rigid base course to reinforce the road base course, and the carbon fiber board is laid at a set spacing along the extension direction of the road surface; The acoustic emission sensors are fixedly installed at one end or both ends of some or all of the carbon fiber boards. The acoustic emission sensors are fixed at the ends of the carbon fiber boards through fixators, and the carbon fiber boards where the acoustic emission sensors are fixed are thickened; The acoustic emission sensors are buried inside the road base course on both sides of the road. Reserved channels are provided on both inner sides of the road base course, and the channels are detachably filled with carbon fiber rods or steel bars; The power supply and data acquisition system is connected to each acoustic emission slave sensor to obtain the data of the acoustic emission sensors and send them to the remote end; After receiving the data of each acoustic emission sensor, the remote processing center analyzes it, and judges the cracking state of the road base course at the corresponding position by judging the deformation or cracking state of each carbon fiber board.

2. The method for preventing and monitoring the cracking state of high-fill subgrade expressways according to claim 1, wherein: The base material of the semi-rigid base course is cement-stabilized macadam, and each layer of the semi-rigid base course is made by rolling cement-stabilized macadam; 3. The method for preventing and monitoring the cracking state of a high-fill subgrade expressway according to claim 2, characterized in that: The carbon fiber board is bonded to each layer of the semi-rigid base course through epoxy resin, and the thickness of the epoxy resin is 1-5 mm; 4. The method for preventing and monitoring the cracking state of a high-fill subgrade expressway according to claim 1 or 2 or 3, characterized in that: The carbon fiber board is fixed to the semi-rigid base course by steel nails; 5. The method for preventing and monitoring the cracking state of high-fill subgrade expressways according to claim 4, characterized in that: The acoustic emission sensors are acoustic emission sensors in a wireless transmission form; 6. The method for preventing and monitoring the cracking state of a high-fill subgrade expressway according to claim 5, characterized in that: The thickness after stacking each layer of the semi-rigid base course is 25-35 cm; 7. The method for preventing and monitoring the cracking state of a high-fill subgrade expressway according to claim 6, characterized in that: The fixator is a fixator with an acoustic emission sensor installation groove, and the fixator is fixed in the layered area of the semi-rigid base course.

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