Road slope grading monitoring system and early warning method

Abstract

The invention belongs to the technical field of slope engineering, and relates to a road slope grading monitoring system and early warning method.The method comprises the following steps that a slope detection grade is established, and the slope detection grade is determined according to monitoring precision, monitoring factors and a coverage surface; determining a monitoring item and a monitoring technical means based on the slope detection grade; and obtaining monitoring data according to the monitoring items and the monitoring technical means, and obtaining a road slope early warning grade according to the monitoring data and a slope grading early warning standard. According to the method and the system, when slope monitoring and early warning are carried out, proper slope monitoring means and influence factors are selected according to the characteristics of the slope to obtain slope displacement, the slope monitoring requirement is met, meanwhile, the economic cost of slope monitoring is reduced, and the overall economic benefit of slope monitoring is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of slope engineering, and relates to a highway slope classification monitoring system and an early warning method. Background Art

[0002] The mechanism of slope instability is complex and there are many influencing factors. When designing a slope monitoring system, comprehensive and in-depth considerations should be made, focusing on the key points in slope monitoring and taking into account various factors that affect slope stability. The development of technical means has provided a wealth of options for slope monitoring. The organic combination of different slope monitoring technical means can form a slope monitoring system with different characteristics, and achieve good monitoring effects based on the characteristics of various slopes. The impact range of slope disasters is closely related to the location of the slope, the conditions of the slope itself, and the surrounding social conditions. Therefore, when designing a graded slope monitoring and early warning system, there are differences in the slope monitoring and control requirements. The use of a differentiated design of slope monitoring and early warning grades can improve the purposefulness, applicability, and economy of the monitoring system design. Summary of the invention

[0003] Slope displacement is the most important indicator for slope stability evaluation and analysis, is the main part of the current common slope monitoring system, and is also the research frontier of current slope monitoring technical means. The present invention comprehensively considers slope displacement and slope displacement monitoring technical means, provides reliable data for slope monitoring and early warning classification, and proposes a highway slope classification monitoring system and early warning method.

[0004] In order to achieve the above objectives, the following technical solutions are proposed: The highway slope classification early warning method includes the following steps: A slope detection level is established, wherein the slope detection level is determined according to monitoring accuracy, monitoring factors and coverage; monitoring items and monitoring technical means are determined based on the slope detection level; monitoring data is acquired according to the monitoring items and monitoring technical means, and a highway slope warning level is obtained according to the monitoring data and the slope classification warning standard.

[0005] As a preferred solution, the slope detection levels include low-level monitoring, medium-level monitoring and high-level monitoring; The low-level slope monitoring method refers to the use of a single monitoring method to monitor the apparent displacement of the slope, taking into account the external key factors of actual slope instability; The medium-level slope monitoring method refers to a slope monitoring system that takes into account multiple main external factors of slope instability and uses multiple means to monitor the three-dimensional displacement of the slope; The high-level slope monitoring method refers to a high-coverage slope monitoring method that takes into account the full set of internal and external factors that affect the actual slope instability and uses a variety of means to monitor the distributed three-dimensional displacement of the slope.

[0006] As a preferred solution, the single monitoring means includes GNSS, three-dimensional laser scanning technology, synthetic aperture radar technology, and slope surface displacement sensor.

[0007] As a preferred solution, the technical indicator requirements for the data obtained by the single monitoring method include: monitoring indicators: slope displacement; monitoring accuracy: horizontal ±2-3mm, vertical ±5mm; coverage range: point monitoring, spacing 50-100m; robustness: small environmental impact, life cycle 3-5 years.

[0008] As a preferred solution, the multiple means are used to monitor the three-dimensional displacement of the slope, and the monitoring means include a borehole inclinometer, a multi-layer settlement meter and a TDR.

[0009] As a preferred solution, the technical indicator requirements for the data obtained by monitoring the three-dimensional displacement of the slope by the multiple means include: monitoring indicators: apparent displacement of the slope, deep displacement; monitoring accuracy: surface displacement: horizontal ±2-3mm, vertical ±5mm; deep displacement: ±0.005-0.01°; coverage range: three-dimensional monitoring, surface point spacing 30-50m, deep point spacing 50-100m; robustness: small environmental impact, life cycle 3-5 years.

[0010] As the preferred solution, the monitoring methods used for high-level slope monitoring include inclinometers, groundwater level meters, distributed optical fibers, rain gauges, three-dimensional aurora scanners, GNSS, and InSAR.

[0011] As a preferred solution, the technical indicator requirements for the data obtained by the high-level slope monitoring include: monitoring indicators: slope displacement, rainfall, pore water pressure; monitoring accuracy: surface displacement: ≤2mm, deep displacement: ±0.005-0.01°; deep displacement: ±0.005-0.01°; coverage: distributed three-dimensional monitoring, key parts are focused on monitoring; robustness: small environmental impact, life cycle 3-5 years.

[0012] Based on the same concept, a highway slope classification monitoring system is also proposed, comprising at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any of the highway slope classification early warning methods described above.

[0013] Compared with the prior art, the present invention has the following beneficial effects: when the method and system of the present invention are used, suitable slope monitoring means and influencing factors are selected to obtain slope displacement according to the characteristics of the slope itself during slope monitoring and early warning. While meeting the needs of slope monitoring, the economic cost of slope monitoring is reduced to improve the overall economic benefits of slope monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a flow chart of the highway slope classification early warning method in Example 1; Figure 2 This is a schematic diagram of low-level monitoring in Example 1; Figure 3 This is a schematic diagram of the intermediate level monitoring in Example 1; Figure 4 This is a schematic diagram of high-level monitoring in Example 1. DETAILED DESCRIPTION

[0015] The present invention is further described in detail below in conjunction with test examples and specific implementation methods. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0016] Example 1 Highway slope classification early warning method, the flow chart is as follows Figure 1 As shown, the following steps are included: A slope detection level is established, wherein the slope detection level is determined according to monitoring accuracy, monitoring factors and coverage; monitoring items and monitoring technical means are determined based on the slope detection level; monitoring data is acquired according to the monitoring items and monitoring technical means, and a highway slope warning level is obtained according to the monitoring data and the slope classification warning standard.

[0017] Based on the investigation of slope instability mechanism and slope monitoring methods and the process of proposing typical slope monitoring and early warning classification, this paper focuses on the importance of slope displacement monitoring and the applicability of various slope displacement monitoring technical means. Therefore, the corresponding slope monitoring classification also has different characteristics and applicability. In the process of constructing slope monitoring and early warning classification, the actual conditions of the slope should be comprehensively considered and appropriate technical means should be selected.

[0018] 1. Low-level monitoring—“apparent displacement index + key factors” The low-level slope monitoring method refers to a slope monitoring system that takes into account the external key factors of actual slope instability and uses various single slope apparent displacements for monitoring, such as Figure 2 As shown. Low-level monitoring cannot obtain the intrinsic physical state of the slope and it is difficult to fully explain the mechanism of slope collapse. However, since the apparent displacement of the slope is intuitively visible, its monitoring implementation is relatively easy and its application is relatively wide. Combined with the acquisition and analysis of key influencing factor data, monitoring and early warning are carried out through the analysis of the displacement development law to achieve the monitoring purpose and benefits under the corresponding slope demand index. This level of monitoring system is usually used for slopes with low monitoring requirements and in addition to the key factors of slope instability, other factors affecting slope instability are not obvious.

[0019] Apparent displacement monitoring is mainly for understanding the changes in slope status, which is passive monitoring; while key influencing factor monitoring is usually based on the actual state of the slope, making a reasonable assessment of the slope stability status and the impact of various factors, and selecting key influencing factor indicators for reasonable monitoring and analysis. This process belongs to active monitoring. Monitoring of key influencing factors of slope stability can provide certain support for the analysis and early warning of slope stability.

[0020] Single means monitoring, all kinds of slope monitoring systems that use a single slope displacement monitoring method belong to the concept of this type of monitoring system. However, in actual applications, due to the contradictions of various technical indicators of the slope monitoring method itself, a single slope apparent displacement monitoring method is usually difficult to meet the higher actual slope monitoring needs. In actual applications, common single means used in slope monitoring systems include GNSS, three-dimensional laser scanning technology, synthetic aperture radar technology, slope surface displacement sensor, etc. There are certain differences in the monitoring content and monitoring indicators considered by different technical means. In the design process of the slope monitoring system, reasonable comparison and selection should also be made according to the actual situation.

[0021] The monitoring system for low-level monitoring has the following technical indicators: ① Single indicator coverage: for slope displacement, single technical means (GNSS, etc.); ② Medium precision guarantee: horizontal ±2-3mm, vertical ±5mm; ③ Low temporal and spatial coverage: point monitoring, spacing 50-100m; ④ Medium robustness: small environmental impact, life cycle 3-5 years; ⑤ Low cost: taking a 100×50m slope as an example, 3 receivers (unit price 20,000) and 1 base station (unit price 20,000) are deployed, with a total price starting from 92,000.

[0022] 2. Intermediate-level monitoring—“three-dimensional displacement index + multiple factors” The medium-level slope monitoring method refers to a slope monitoring system that takes into account multiple main external factors of slope instability and uses multiple means to monitor the three-dimensional displacement of the slope, such as Figure 3 As shown. Intermediate-level monitoring monitors the apparent displacement and deep displacement with low coverage, and combined with the monitoring data of the main influencing factors of the actual slope, it can achieve a higher degree of perception of the actual state of the slope and interpretation of the instability process mechanism, so as to achieve the monitoring purpose and benefits under the corresponding slope demand index. This level of monitoring system is suitable for slopes with high monitoring requirements and multiple obvious influencing factors of slope instability.

[0023] Stereoscopic displacement monitoring can be divided into surface displacement monitoring and deep displacement monitoring according to the difference in monitoring content. Compared with deep displacement monitoring, surface displacement is intuitively visible, the monitoring implementation is relatively easy, and it is also widely used; deep displacement monitoring means are relatively complex, and usually point monitoring. However, the results of deep displacement monitoring can better reveal the position of the sliding surface of the landslide and the displacement trend of the sliding surface, and compared with the surface displacement monitoring of the slope, the error of deep displacement monitoring is relatively small. Combining the surface displacement monitoring of the slope with the deep displacement monitoring can construct the three-dimensional spatial form of the slope displacement monitoring, and then realize the three-dimensional spatial analysis of the overall movement situation of the slope. At present, the monitoring of deep displacement usually requires the sensor to be buried inside the slope. Therefore, deep displacement monitoring of slopes is currently commonly used in soil slopes, but is less used in rock slopes.

[0024] At present, common methods for monitoring deep displacement of slopes mainly include borehole inclinometers, multi-layer settlement meters, and TDR. Deep displacement is usually combined with large-scale surface displacement monitoring methods to achieve coordinated analysis of surface displacement and deep displacement. When using point surface displacement monitoring, it is often difficult to achieve coordinated analysis of three-dimensional spatial displacement due to the large difference between the two types of monitoring locations.

[0025] The monitoring system of medium-level monitoring has the following technical indicators: ① Multi-indicator coverage: multi-technical means are used to jointly monitor the apparent displacement and deep displacement of the slope; ② High-precision guarantee: surface displacement: horizontal ±2-3mm, vertical ±5mm; deep displacement: ±0.005-0.01°; ③ Medium temporal and spatial coverage: three-dimensional monitoring, surface point spacing of 30-50m, deep point spacing of 50-100m; ④ High robustness: small environmental impact, life cycle of 3-5 years; ⑤ High cost: taking a 100×50m slope as an example, 5 receivers (unit price of 20,000), 1 base station (unit price of 20,000), 3 inclinometer holes (35,000), 1 rain gauge (12,000), and 9 pore water pressure gauges (5,000) are deployed, with a total price starting from 282,000.

[0026] 3. High-level monitoring—"distributed three-dimensional displacement + all factors" The high-level slope monitoring method refers to a high-coverage slope monitoring system that takes into account the full set of internal and external factors that cause actual slope instability and uses a variety of means to monitor the distributed three-dimensional displacement of the slope, such as Figure 4 As shown. High-level monitoring uses high-coverage distributed monitoring methods for apparent displacement and deep displacement, combined with monitoring data of actual internal and external influencing factors of the slope, to establish an analysis chain of "all factors - internal state of the slope - apparent state of the slope", which can achieve a high degree of perception of the actual state of the slope and interpretation of the mechanism of the instability process, so as to achieve the monitoring purpose and benefits under the corresponding slope demand index. This level of monitoring system is suitable for slopes with high monitoring requirements and both internal and external influencing factors.

[0027] Distributed stereo displacement monitoring refers to the use of advanced distributed optical fiber technology to achieve high coverage monitoring of stereo displacement. Distributed optical fiber technology can obtain strain data of all objects to be measured along the laid optical fiber, and conduct high-density slope displacement and deep displacement monitoring through different laying densities, thereby establishing a refined evolution process analysis of the slope stereo displacement, capturing the precise position of the sliding surface, and providing strong support for the slope instability process and mechanism analysis.

[0028] All-factor joint monitoring is the most widely used method in the current design of slope monitoring systems. Different from simple displacement monitoring, multi-factor joint monitoring monitors internal and external related factors that may affect slope stability while performing displacement monitoring. In the process of designing a full-factor joint monitoring system, the climate environment, geological conditions and human activities around the slope should be fully investigated, and the main factors affecting slope stability should be analyzed and determined based on the investigation. In addition, the stress and strain monitoring of the slope and its ancillary structures can also provide an effective reference for the overall stability analysis of the slope, and thus select relevant monitoring methods to achieve targeted design of the slope monitoring system. Among the current analysis of factors affecting the stability of various slopes, rainfall, soil humidity, and groundwater level changes are the most important factors, but these two factors usually have a greater impact on the stability of soil slopes or rock-soil mixed slopes. In the design of slope monitoring systems, technical means such as rain gauges, hygrometers, and groundwater level collectors are usually used to achieve effective monitoring of the above-mentioned factors affecting slope stability. As for the stress state of the slope and the stress and strain changes of the attached structures, the commonly used monitoring methods mainly include earth pressure gauges, stress gauges and strain gauges.

[0029] The monitoring system of high-level monitoring has the following technical indicators: ① Multi-indicator coverage: multi-technical means are used to jointly monitor slope displacement, rainfall, pore water pressure, etc.; ② High-precision guarantee: surface displacement: ≤2mm, deep displacement: ±0.005-0.01°; ③ High temporal and spatial coverage: distributed three-dimensional monitoring, key parts are monitored; ④ High robustness: small environmental impact, life cycle of 4-5 years; ⑤ High cost: taking a 100×50m slope as an example, 2km of distributed optical fiber is laid (unit price of 10,000), 1 distributed optical fiber demodulator (unit price of 600,000), 3 incline holes (8,000), 3 fiber grating crack meters (unit price of 2,000), 3 fiber grating earth pressure meters (unit price of 2,000), 1 fiber grating demodulator (unit price of 150,000), 1 rain gauge (12,000), 9 pore water pressure meters (5,000), with a total price starting from 900,000.

[0030] 4. Manually assisted key monitoring Artificially assisted key monitoring is to further verify and improve the effectiveness of the slope monitoring system by using the method of regular expert inspections based on the slope monitoring system. The current research on slope instability and slope monitoring theory still has certain limitations. Therefore, its reliability still needs more verification when applied to actual slope monitoring. There is a certain similarity in the geological conditions of slopes in the same area. When analyzing the stability of slopes, surrounding slopes with similar geological conditions can usually provide an effective reference for the analysis of the target slope. In this process, engineering professionals in the area can usually play an important role.

[0031] Therefore, the use of regular inspections by experts can make up for the uncertainty of the slope monitoring system itself and provide strong support for slope stability analysis and early warning from other channels. However, the manual inspection method is greatly affected by the environmental conditions around the slope. When the slope is steep or the surrounding environment is harsh, it is usually difficult to survey such slopes. Therefore, this method is usually applied to slopes where the surrounding environment can carry out related work or slopes that need to be monitored and analyzed.

[0032] On the basis of comprehensive analysis, this study proposed different levels of slope monitoring content setting methods based on the needs of different design levels of slope monitoring systems, as shown in Table 1. At the same time, according to the basic requirements of advanced monitoring methods and the connotations of different levels of monitoring systems, the combination method with cutting-edge slope monitoring methods was given, as shown in Table 2.

[0033] Table 1 Setting methods for monitoring contents of different levels of slopes Table 2 Slope monitoring and early warning classification design and combination of advanced monitoring methods In general, with the improvement of the slope monitoring warning level, the monitoring accuracy of the entire slope monitoring system is improved, the types of monitoring factors are more complete, and the coverage capacity of the slope monitoring system in time and space is gradually enhanced. Among the frontier slope monitoring methods designed in this special report, distributed optical fiber has good time and space coverage, but the construction cost and operation and maintenance cost of the monitoring system based on distributed optical fiber are relatively high. Therefore, the slope monitoring system based on distributed optical fiber is more suitable for high-level slope monitoring projects, but not recommended for low-level slope monitoring projects. Digital close-range photogrammetry technology has low cost and wide coverage, but the monitoring accuracy is relatively low, and it is greatly affected by environmental factors. Therefore, this technology is mostly recommended for low-level monitoring, but not for high-level monitoring. Global navigation satellite (GNSS) monitoring accuracy is high, but the monitoring coverage is small. Therefore, global navigation satellite technology can be applied in slope monitoring projects of different levels as an important part of overall slope displacement monitoring. Three-dimensional laser scanning technology is similar to digital close-range photogrammetry technology. It has the characteristics of wide coverage, but the monitoring accuracy and monitoring cost are relatively high. Therefore, it is also recommended for higher-level slope monitoring systems. The measurement accuracy of 3D laser scanning technology is also closely related to the surface state of the slope, and may face problems such as insufficient accuracy in high-level variable slope monitoring. Space-based synthetic aperture radar technology has the characteristics of extremely wide coverage and can be used for large-scale low-level slope monitoring, but the monitoring accuracy is difficult to meet the needs of high-level slope monitoring. Ground-based synthetic aperture radar technology has the characteristics of high monitoring accuracy and can be recommended for use in high-level slope monitoring, but due to the relatively high technical cost, it is not recommended for use in low-level slope monitoring.

[0034] Finally, it should be noted that the embodiments described in detail above are only the best practices of the invention and cannot be used to limit the scope of rights of the invention. Equivalent replacement of the technical solutions recorded in the aforementioned embodiments does not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the invention, and they should all be included in the scope of the claims and description of the invention.

Claims

1. A highway slope classification early warning method, characterized in that: The following steps are involved: A slope detection level is established, wherein the slope detection level is determined according to monitoring accuracy, monitoring factors and coverage; monitoring items and monitoring technical means are determined based on the slope detection level; monitoring data is acquired according to the monitoring items and monitoring technical means, and a highway slope warning level is obtained according to the monitoring data and the slope classification warning standard.

2. The highway slope classification early warning method according to claim 1, characterized in that: The slope detection levels include low-level monitoring, medium-level monitoring and high-level monitoring; The low-level slope monitoring method refers to the use of a single monitoring method to monitor the apparent displacement of the slope, taking into account the external key factors of actual slope instability; The medium-level slope monitoring method refers to a slope monitoring system that takes into account multiple main external factors of slope instability and uses multiple means to monitor the three-dimensional displacement of the slope; The high-level slope monitoring method refers to a high-coverage slope monitoring method that takes into account the full set of internal and external factors that affect the actual slope instability and uses a variety of means to monitor the distributed three-dimensional displacement of the slope.

3. The highway slope classification early warning method according to claim 2, characterized in that: The single monitoring means include GNSS, three-dimensional laser scanning technology, synthetic aperture radar technology, and slope surface displacement sensor.

4. The highway slope classification early warning method according to claim 3, characterized in that: The technical indicator requirements for the data obtained by using the single monitoring method include: monitoring indicators: slope displacement; monitoring accuracy: horizontal ±2-3mm, vertical ±5mm; coverage range: point monitoring, spacing 50-100m; robustness: small environmental impact, life cycle 3-5 years.

5. The highway slope classification early warning method according to claim 2, characterized in that: The multiple means are used to monitor the three-dimensional displacement of the slope, and the monitoring means include a borehole inclinometer, a multi-layer settlement meter and a TDR.

6. The highway slope classification early warning method according to claim 5, characterized in that: The technical indicator requirements for the data obtained by monitoring the three-dimensional displacement of the slope by the various means include: monitoring indicators: apparent displacement and deep displacement of the slope; monitoring accuracy: surface displacement: horizontal ±2-3mm, vertical ±5mm; deep displacement: ±0.005-0.01°; coverage range: three-dimensional monitoring, surface point spacing 30-50m, deep point spacing 50-100m; robustness: small environmental impact, life cycle 3-5 years.

7. The highway slope classification early warning method according to claim 2, characterized in that: The monitoring methods used for high-level slope monitoring include inclinometers, groundwater level meters, distributed optical fibers, rain gauges, three-dimensional aurora scanners, GNSS, and InSAR.

8. The highway slope classification early warning method according to claim 7, characterized in that: The technical indicator requirements for the data obtained from the high-level slope monitoring include: monitoring indicators: slope displacement, rainfall, pore water pressure; monitoring accuracy: surface displacement: ≤2mm, deep displacement: ±0.005-0.01°; deep displacement: ±0.005-0.01°; coverage: distributed three-dimensional monitoring, key areas focused on monitoring; robustness: small environmental impact, life cycle 3-5 years.

9. A highway slope classification monitoring system, characterized in that: The method comprises at least one processor and a memory in communication with the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the highway slope classification warning method according to any one of claims 1 to 8.

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