Underground engineering construction safety risk real-time early warning method based on Internet of Things

Abstract

The invention relates to the technical field of data processing, and provides an underground engineering construction safety risk real-time early warning method based on the Internet of Things, which comprises the following steps: obtaining initial setting fluctuation difference according to a fluctuation difference relationship of strain values, and obtaining a stable trend according to a fluctuation stable trend of the strain values; obtaining the strain accuracy degree according to the initial setting fluctuation difference and the stability tendency; obtaining a formation starting moment according to the change of the strain accuracy degree; obtaining a solidification corresponding moment according to the difference of the formation starting moments; obtaining a risk index according to the increase duration of the strain value at the solidification corresponding moment; and obtaining an underground engineering construction safety risk real-time early warning result according to the risk index. According to the invention, the underground engineering construction safety risk is early warned in real time through the risk index, the accuracy of the real-time early warning result is improved, and the risk of underground engineering construction is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and particularly to a real-time early warning method for the construction safety risks of underground projects based on the Internet of Things. Background Art

[0002] Underground projects refer to various construction projects carried out below the ground surface, usually including tunnels, underground transportation systems, underground shopping malls, subways, underground pipelines, underground storage facilities, etc. Underground projects require excavation, support, construction, and management underground, involving complex geological conditions, hydrological environments, and spatial layouts. The construction of underground projects not only has to deal with technical problems such as geotechnical mechanics and groundwater control, but also needs to consider various factors such as safety, environmental protection, ventilation, and drainage, with relatively high technical requirements and construction difficulties.

[0003] During the construction of underground projects, due to factors such as geological conditions, improper construction, and failure of the support structure, there is a risk of ground collapse or wall collapse in the underground space. The collapse may cause serious consequences such as large-scale casualties, equipment damage, and project suspension. The risks mainly come from unstable soil layers, groundwater seepage, insufficient support systems or design defects, especially in special working environments such as deep foundation pits, tunnels, and mines, so it is necessary to conduct real-time early warning of the construction safety risks of underground projects.

[0004] During the construction of underground projects, in order to ensure the stability of the excavated structure, it is necessary to install a cast-in-place concrete structure at the excavation edge or around to form a retaining structure to support the soil. In order to monitor the pressure borne by the concrete structure, currently, a method of installing a concrete strain gauge at the top of the concrete support during concrete pouring is adopted, and the concrete strain gauge is used for real-time monitoring and early warning of the concrete pressure. After the concrete is poured and formed, the support structure successfully bears the collapse force, and after the concrete strength is fully developed, the reading of the concrete strain gauge will gradually converge and finally stabilize within the design allowable range, and the concrete strain gauge is used for real-time monitoring and early warning of the pressure borne by the concrete. However, when the concrete has not yet formed strength after pouring, the collapse force at the top of the tunnel is directly transmitted to the unhardened concrete structure, and the reading of the concrete strain gauge cannot directly show the strain degree of the tunnel within the monitored range, reducing the accuracy of the real-time early warning result. And because the newly excavated tunnel is the most likely to have a collapse risk, the risk of underground project construction is increased. Summary of the Invention

[0005] The present invention provides a real-time early warning method for the construction safety risks of underground projects based on the Internet of Things to solve the problems of relatively low accuracy of the existing real-time early warning results and relatively high risk of underground project construction. The specific technical solutions adopted are as follows: The present invention provides a real-time early warning method for the safety risks of underground engineering construction based on the Internet of Things. The method includes the following steps: Obtain the strain monitoring sequence of each concrete strain gauge; the strain monitoring sequence contains a number of strain values; Denote any one concrete strain gauge as the target concrete strain gauge, and denote any one strain value in the strain monitoring sequence of the target concrete strain gauge as the target strain value; according to the fluctuation difference relationship between the target strain value and the strain values in the strain monitoring sequence of the target concrete strain gauge, obtain the initial setting fluctuation difference of the target strain value; according to the fluctuation stability trend of the strain values in the strain monitoring sequence of the target concrete strain gauge, obtain the stability trend of the target strain value; according to the initial setting fluctuation difference and the stability trend of the target strain value, obtain the strain accuracy of the target strain value; According to the change of the strain accuracy of the strain values in the strain monitoring sequence of the target concrete strain gauge, obtain the starting moment of the formation of the target concrete strain gauge; according to the difference relationship between the starting moment of the formation of the target concrete strain gauge and that of other concrete strain gauges, obtain the solidification corresponding moment of the target strain value in the strain monitoring sequence of each concrete strain gauge; According to the increasing duration of the strain values at the solidification corresponding moments of the target strain value in the strain monitoring sequences of all concrete strain gauges, obtain the risk index of the target strain value; Obtain the real-time early warning result of the safety risks of underground engineering construction according to the risk index of the target strain value.

[0006] Further, the method for obtaining the initial setting fluctuation difference of the target strain value according to the fluctuation difference relationship between the target strain value and the strain values in the strain monitoring sequence of the target concrete strain gauge includes the following specific method: Construct a window with a length of centered on the target strain value, denoted as the adjacent window of the target strain value; denote the variance of all strain values within the adjacent window of the target strain value as the adjacent fluctuation index of the target strain value; where, is the preset window length; Obtain the initial setting fluctuation difference of the target strain value according to the difference of the adjacent fluctuation indices of the strain values within the adjacent window of the target strain value.

[0007] Further, the method for obtaining the initial setting fluctuation difference of the target strain value according to the difference of the adjacent fluctuation indices of the strain values in the strain monitoring sequence of the target concrete strain gauge includes the following specific method: Obtain the mean value of the adjacent fluctuation indices of all strain values within the adjacent window of the target strain value, and denote the difference obtained by subtracting the mean value from the maximum value of the adjacent fluctuation indices of all the monitored strain values of the target concrete strain gauge as the initial setting fluctuation difference of the target strain value.

[0008] Further, obtaining the stability trend of the target strain value according to the fluctuation stability trend of the strain values in the strain monitoring sequence of the target concrete strain gauge, the specific obtaining method is as follows: In the formula, is the stability trend of the target strain value; is the adjacent fluctuation index of the th strain value in the strain monitoring sequence of the target concrete strain gauge; is the adjacent fluctuation index of the th strain value in the strain monitoring sequence of the target concrete strain gauge; is the ordinal number of the target strain value in the strain monitoring sequence of the target concrete strain gauge; is the absolute value function.

[0009] Further, obtaining the strain accuracy of the target strain value according to the initial setting fluctuation difference and stability trend of the target strain value, the specific method included is as follows: Taking the product of the initial setting fluctuation difference and stability trend of the target strain value as the strain accuracy of the target strain value.

[0010] Further, obtaining the formation start time of the target concrete strain gauge according to the change situation of the strain accuracy of the strain values in the strain monitoring sequence of the target concrete strain gauge, the specific method included is as follows: Denoting the difference obtained by subtracting the strain accuracy of the previous strain value from the strain accuracy of the target strain value as the stage change degree of the target strain value; Denoting the time when the strain value with the largest stage change degree in the strain monitoring sequence of the target concrete strain gauge as the formation start time of the target concrete strain gauge.

[0011] Further, obtaining the solidification corresponding time of the target strain value in the strain monitoring sequence of each concrete strain gauge according to the difference relationship of the formation start times between the target concrete strain gauge and other concrete strain gauges, the specific method included is as follows: In the formula, is the solidification corresponding time of the target strain value in the strain monitoring sequence of the th concrete strain gauge; is the formation start time of the th concrete strain gauge; is the formation start time of the target concrete strain gauge; is the ordinal number of the target strain value in the strain monitoring sequence of the target concrete strain gauge; is the floor function.

[0012] Furthermore, the method for obtaining the risk index of the target strain value according to the increase and continuation of the strain value at the solidification corresponding moment in the strain monitoring sequences of all concrete strain gauges specifically includes: The difference obtained by subtracting the strain value at the solidification corresponding moment of the previous concrete strain gauge of the target concrete strain gauge from the target strain value is denoted as the change amount of the target strain value; The calculation method of the change increase index of the target strain value is: In the formula, is the change increase index of the target strain value; is the change amount of the target strain value; is the change amount of the strain value at the solidification corresponding moment of the previous concrete strain gauge of the target concrete strain gauge of the target strain value; is the absolute value function; According to the increase and continuation of the strain value at the solidification corresponding moment in the strain monitoring sequences of all concrete strain gauges, the risk index of the target strain value is obtained.

[0013] Furthermore, the method for obtaining the risk index of the target strain value according to the increase and continuation of the strain value at the solidification corresponding moment in the strain monitoring sequences of all concrete strain gauges specifically includes: In the formula, is the risk index of the target strain value; is the th concrete strain gauge to all concrete strain gauges of the target concrete strain gauge, and is the minimum value of the change increase index of the strain value at the solidification corresponding moment of the target strain value in all the concrete strain gauges; is the change increase index of the strain value at the solidification corresponding moment of the target strain value in the th concrete strain gauge; is the total number of the laid concrete strain gauges.

[0014] Furthermore, the method for specifically obtaining the real-time early warning result of the construction safety risk of the underground project according to the risk index of the target strain value is: If the risk index of the target strain value is greater than the preset risk threshold, there is a collapse risk.

[0015] The beneficial effects of the present invention are as follows: During the construction of underground projects, since the newly excavated passage is the one most likely to have a collapse risk, it is necessary to monitor the strain values of the newly excavated passage. Since the concrete strain gauges on the concrete poured in the newly excavated passage cannot accurately display the actual strain values during the initial setting stage of concrete solidification, the present invention obtains the accuracy of the target strain value based on the initial setting fluctuation difference and stable trend of the target strain value, and determines the concrete solidification stage at which each strain value is located; During the process of passage excavation, due to changes in geological conditions, there are differences in the solidification times of the concrete at the locations of different concrete strain gauges. Therefore, when comparing the strain values of different concrete strain gauges, it is impossible to use the strain values at the same solidification moment in the strain monitoring sequence for comparison. The present invention obtains the corresponding solidification moment of the target strain value in the strain monitoring sequence of each concrete strain gauge through the difference relationship between the start time of the target concrete strain gauge and other concrete strain gauges, and obtains the comparison correspondence relationship between different concrete strain gauges; Since, in the direction of excavation, the change in strain values between concrete strain gauges is gradual, if the gradual trend is that as the excavation depth increases, the strain values of the concrete strain gauges become larger and the change speed becomes faster, then a collapse accident is more likely to occur. The present invention obtains the risk index of the target strain value through the continuous increase of the strain values at the corresponding solidification moments of the target strain value in the strain monitoring sequences of all concrete strain gauges. Thus, the present invention obtains the real-time warning result of the construction safety risk of the underground project through the risk index of the target strain value, improves the accuracy of the real-time warning result, and reduces the risk of underground project construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a schematic flowchart of a real-time warning method for construction safety risks of underground projects based on the Internet of Things provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0019] Please refer to Figure 1 , which shows a flowchart of a real-time early warning method for the safety risks of underground engineering construction based on the Internet of Things provided by an embodiment of the present invention. The method includes the following steps: Step S001: Obtain the strain monitoring sequence of each concrete strain gauge.

[0020] It should be noted that the purpose of the present invention is to perform real-time early warning on the safety risks of the excavation of underground channels during underground engineering construction. The latest excavated channel is the one most likely to have a collapse risk. Therefore, it is necessary to collect and analyze the construction data during the excavation process of the underground channel in real time.

[0021] Specifically, during the construction of underground engineering, for the excavated underground channel, starting from the entrance of the channel, concrete is poured for the newly excavated channel section to support the soil. When pouring concrete, a concrete strain gauge is installed every meters at the top of the concrete support, where is the preset installation interval, and this embodiment takes as an example for description; During the construction of underground engineering, the strain values of all installed concrete strain gauges are collected in real time at a frequency of once every minutes. For any concrete strain gauge, the time series sequence composed of all the strain values collected by the concrete strain gauge is recorded as the strain monitoring sequence of the concrete strain gauge; where is the preset collection frequency, and this embodiment takes as an example for description.

[0022] Step S002: Denote any concrete strain gauge as the target concrete strain gauge, and denote any strain value in the strain monitoring sequence of the target concrete strain gauge as the target strain value; obtain the initial setting fluctuation difference of the target strain value according to the fluctuation difference relationship between the target strain value and the strain values in the strain monitoring sequence of the target concrete strain gauge; obtain the stability trend of the target strain value according to the fluctuation stability trend of the strain values in the strain monitoring sequence of the target concrete strain gauge; and obtain the strain accuracy of the target strain value according to the initial setting fluctuation difference and the stability trend of the target strain value.

[0023] It should be noted that after the concrete is poured, the solidification stage of the concrete is mainly divided into the initial setting stage, the strength formation stage, and the long-term stability stage. Among them, the duration of the initial setting stage of the concrete is relatively short, often several hours, which is specifically determined by the concrete mix ratio, ambient temperature, humidity, and cement type, etc., and the duration is uncertain. During the initial setting stage of the concrete, due to the influence of material plasticity, temperature, and construction disturbance on the concrete strain gauge, it is impossible to directly and accurately reflect the load strain. Compared with the initial setting stage of the concrete, the strength formation stage is more suitable for using the concrete strain gauge for monitoring. Because during the strength formation stage, the concrete has begun to harden and gradually has a certain strength, the plastic deformation decreases, the concrete enters the elastic stage, and the strain gauge can more stably reflect the true strain change of the concrete, the data is more reliable and has higher accuracy, and it can effectively monitor the strain and stress state of the concrete under the action of the load. In order to improve the accuracy of concrete strain monitoring, it is necessary to distinguish the data in the initial setting stage of the concrete from the data in the strength formation stage and the long-term stability stage.

[0024] It should be further noted that during the initial setting stage of the concrete, the concrete is still in the transition state from liquid to semi-liquid, the cement hydration reaction has just started, and there is relatively large plastic deformation, resulting in large fluctuations and instability in the data recorded by the strain gauge. The reference of the strain values collected in this stage is not strong; while in the strength formation stage, the concrete hardens and gradually has a certain strength, the deformation tends to be elastic, and the data changes smoothly. The reference of the strain values collected in this stage is relatively strong. Therefore, for any concrete strain gauge, judge the strain reference of each strain value collected by it.

[0025] Specifically, denote any concrete strain gauge as the target concrete strain gauge, and denote any strain value in the strain monitoring sequence of the target concrete strain gauge as the target strain value. Construct a window with a length of centered on the target strain value, and denote it as the adjacent window of the target strain value; denote the variance of all strain values within the adjacent window of the target strain value as the adjacent fluctuation index of the target strain value; among them, is the preset window length, and this embodiment takes as an example for description; it should be noted that if some strain values do not exist in the window with a length of centered on the target strain value, only the existing strain values are retained within the adjacent window of the target strain value.

[0026] It should be noted that since the strain values in the initial setting stage of concrete fluctuate greatly and irregularly, the adjacent fluctuation index of the strain values in the initial setting stage of concrete is much larger than that in the strength formation stage. That is, the adjacent fluctuation index of the strain values is the largest in the initial setting stage of concrete. The greater the difference between the adjacent fluctuation index of the strain value and the maximum adjacent fluctuation index, the farther it is from the initial setting stage of concrete, that is, the more likely it belongs to the strength formation stage.

[0027] Specifically, the mean value of the adjacent fluctuation indices of all strain values within the adjacent window of the target strain value is obtained, and the difference obtained by subtracting the mean value from the maximum value of the adjacent fluctuation indices of all the monitored strain values of the target concrete strain gauge is denoted as the initial setting fluctuation difference of the target strain value.

[0028] It should be noted that the strain values in the strength formation stage fluctuate less and show a gradually stable trend. Therefore, from the initial setting stage of concrete to the strength formation stage, the adjacent fluctuation index of the strain values has an obvious trend of steadily decreasing. Therefore, the stable trend of the target strain value is calculated based on this.

[0029] Specifically, the calculation method of the stable trend of the target strain value is as follows: In the formula, is the stable trend of the target strain value; is the adjacent fluctuation index of the th strain value in the strain monitoring sequence of the target concrete strain gauge; is the adjacent fluctuation index of the th strain value in the strain monitoring sequence of the target concrete strain gauge; is the ordinal number of the target strain value in the strain monitoring sequence of the target concrete strain gauge; is the absolute value function.

[0030] It should be noted that The closer the value of , that is, is closer to 1, it indicates that in the process from the initial strain value in the strain monitoring sequence of the target concrete strain gauge to the target strain value, the change of the strain value has changed towards a stable trend, and the target strain value already has a stable trend.

[0031] It should be noted that when the initial setting fluctuation difference of the strain value is greater, it indicates that the strain value is farther from the initial setting stage of concrete. At the same time, if the stable trend of the strain value is greater, it indicates that the moment when the strain value is located is more likely to have entered the strength formation stage. When entering the strength formation stage, the strain value will more stably reflect the true strain change of concrete, and the data is more reliable and has higher accuracy. Then, the strain accuracy of each strain value is calculated based on this.

[0032] Specifically, the product of the initial setting fluctuation difference and the stable trend of the target strain value is used as the strain accuracy of the target strain value.

[0033] It should be noted that the larger the strain accuracy of the strain value, the less it belongs to the initial setting stage of concrete, and the higher the credibility in strain analysis.

[0034] Step S003: Obtain the starting moment of the formation of the target concrete strain gauge according to the change of the strain accuracy of the strain values in the strain monitoring sequence of the target concrete strain gauge; according to the difference relationship between the starting moment of the formation of the target concrete strain gauge and that of other concrete strain gauges, obtain the corresponding solidification moment of the target strain value in the strain monitoring sequence of each concrete strain gauge.

[0035] It should be noted that during the construction of underground projects, the concrete mix used for the concrete pouring of the excavation passage is the same. In theory, the strain values of different concrete strain gauges should be similar at the same stage moment. Therefore, it is necessary to compare the strain values of different concrete strain gauges at the same stage moment. However, as the excavation depth increases, environmental factors such as underground temperature and humidity will change, which may affect the speed of the cement hydration reaction, resulting in the need to adjust the comparison moment when comparing every two concrete strain gauges.

[0036] It should be further noted that when comparing any two concrete strain gauges, since the location environments of the two concrete strain gauges are different, when comparing the strain values, it is necessary to judge the influence of different environments on the solidification duration of the concrete at the location of the concrete strain gauge. During the concrete solidification process, the moment with the most obvious change characteristics is the moment when the concrete changes from the initial setting stage to the strength formation stage. The change in the strain accuracy at this moment is the largest. Therefore, based on this, obtain the starting moment when the concrete at the location of the concrete strain gauge changes from the initial setting stage to the strength formation stage, and then obtain the corresponding solidification moment for comparing the strain values of the two concrete strain gauges according to the difference between the starting moments of the formation of the concrete strain gauges.

[0037] Specifically, the difference obtained by subtracting the strain accuracy of the previous strain value from the strain accuracy of the target strain value is denoted as the stage change degree of the target strain value; it should be noted that the stage change degree of the first strain value in the strain monitoring sequence of the target concrete strain gauge is 0; The moment corresponding to the strain value with the largest stage change degree in the strain monitoring sequence of the target concrete strain gauge is recorded as the starting moment of the formation of the target concrete strain gauge; The target strain value is at the The calculation method for the corresponding solidification moment in the strain monitoring sequence of a concrete strain gauge is as follows: In the formula, is the corresponding solidification moment of the target strain value in the strain monitoring sequence of the th concrete strain gauge; is the start moment of the formation of the th concrete strain gauge; is the start moment of the formation of the target concrete strain gauge; is the ordinal number of the target strain value in the strain monitoring sequence of the target concrete strain gauge; is the floor function.

[0038] It should be noted that is the proportional relationship between the target concrete strain gauge and the th concrete strain gauge for the duration from the pouring of concrete to the transition to the strength formation stage. This proportional relationship indicates that due to the different environmental positions of the target concrete strain gauge and the th concrete strain gauge, the required solidification duration of the concrete at their positions changes. Thus, by adjusting , the corresponding solidification moment of the target strain value in the strain monitoring sequence of the th concrete strain gauge is obtained.

[0039] Step S004: Obtain the risk index of the target strain value based on the increasing and continuous situation of the strain values at the corresponding solidification moments in the strain monitoring sequences of all concrete strain gauges.

[0040] It should be noted that during the construction of underground projects, different geological conditions may lead to the risk of collapse during excavation. That is, in actual situations, the changes in the strain values monitored by different concrete strain gauges are different. During the solidification of concrete, the strain values in the normal strain monitoring data are relatively small in the initial setting stage of concrete, gradually increase in the strength formation stage, and increase slowly and gradually converge in the long-term stable stage.

[0041] It should be further noted that, theoretically, the strain values of different concrete strain gauges should be similar at the same stage, but due to the different geological environments, the change processes of the strain values of different concrete strain gauges during the solidification process also vary, and there are differences between the strain value of each concrete strain gauge and the strain value at the corresponding solidification moment of other concrete strain gauges. However, since the geological environment changes gradually with the excavation depth, the change of the strain values between the concrete strain gauges is also gradual in the excavation direction. But if the trend of the gradual change is that as the excavation depth increases, the strain values of the concrete strain gauges become larger and larger, and the change speed becomes faster and faster, then the risk of collapse is more likely. Therefore, first, the change amount of the strain values of the concrete strain gauges is measured.

[0042] Specifically, the difference obtained by subtracting the strain value at the corresponding solidification moment of the previous concrete strain gauge of the target concrete strain gauge from the target strain value is denoted as the change amount of the target strain value. It should be noted that the concrete strain gauges are laid at equal intervals in sequence as the excavation depth increases, and the order of the concrete strain gauges is arranged according to the laying order.

[0043] It should be noted that when a collapse accident may occur, as the excavation depth increases, in the excavation direction, the strain values between adjacent concrete strain gauges will gradually increase and the change amount will become larger and larger. For a certain concrete strain gauge, if the change amount of the reading compared with the previous adjacent concrete strain gauge increases, it means that from the perspective of this concrete strain gauge alone, it conforms to the local change trend of the strain values of the strain gauges before collapse. Based on this, the change increase index of each strain value is calculated.

[0044] Specifically, the calculation method of the change increase index of the target strain value is as follows: In the formula, is the change increase index of the target strain value; is the change amount of the target strain value; is the change amount of the strain value at the corresponding solidification moment of the previous concrete strain gauge of the target concrete strain gauge; is the absolute value function.

[0045] It should be noted that When it is 1, it means that the change amount of the target strain value has increased compared with the change amount of the strain value at the corresponding solidification moment of the previous concrete strain gauge of the target concrete strain gauge, which conforms to the local change trend of the concrete strain gauges before collapse. When it is 0, it indicates that the change amount of the target strain value has decreased compared to the change amount of the strain value at the corresponding solidification moment of the previous concrete strain gauge of the target concrete strain gauge, which does not conform to the local change trend of the concrete strain gauge before collapse.

[0046] It should be noted that before the impending collapse, in the direction of excavation, the strain value will gradually increase, and the increasing speed will become faster and faster, that is, this phenomenon shows continuity, that is, the change increase index of the strain value remains 1 continuously. If the duration of the change increase index being 1 is relatively long, it conforms to the trend change of collapse. Therefore, according to the persistence of the change increase index of the strain value being 1, the risk index of each strain value is judged.

[0047] Specifically, the calculation method of the risk index of the target strain value is as follows: In the formula, is the risk index of the target strain value; is the minimum value of the change increase index of the strain value at the corresponding solidification moment of the target strain value among all the concrete strain gauges from the th concrete strain gauge to the target concrete strain gauge; is the change increase index of the strain value at the corresponding solidification moment of the target strain value in the th concrete strain gauge; is the total number of the laid concrete strain gauges.

[0048] It should be noted that The larger the , the longer the duration of the change increase index of the target strain value being 1, that is, as the underground engineering construction excavation progresses, the increasing trend of the strain value becomes more and more obvious, and the risk of collapse is more likely to occur.

[0049] Step S005, obtain the real-time warning result of the construction safety risk of the underground project according to the risk index of the target strain value.

[0050] It should be noted that the larger the risk index of the strain value of the concrete strain gauge, the greater the collapse risk shown by the strain value and the greater the risk degree during excavation.

[0051] Specifically, if the risk index of the target strain value is greater than the preset risk threshold, it indicates that there may be a collapse risk. The relevant construction activities should be suspended or stopped, and the on-site management personnel, technical personnel and safety responsible persons should be notified to conduct on-site investigation and evaluate the stability of the soil support structure; if it is confirmed that there is a collapse risk, the support measures should be strengthened, such as adding supports, strengthening the concrete structure or adjusting the excavation plan to ensure the safety of the construction personnel; among them, the preset risk threshold is 15, and this embodiment is described by taking this as an example. Judge each strain value of each concrete strain gauge according to the above method, and take corresponding risk response measures when necessary.

[0052] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A real-time early warning method for underground engineering construction safety risks based on the Internet of Things, characterized in that: The method comprises the following steps: Obtaining a strain monitoring sequence of each concrete strain gauge; the strain monitoring sequence includes a plurality of strain values; Any concrete strain gauge is recorded as a target concrete strain gauge, and any strain value in the strain monitoring sequence of the target concrete strain gauge is recorded as a target strain value; the initial setting fluctuation difference of the target strain value is obtained according to the fluctuation difference relationship between the target strain value and the strain value in the strain monitoring sequence of the target concrete strain gauge; the stability trend of the target strain value is obtained according to the fluctuation stability trend of the strain value in the strain monitoring sequence of the target concrete strain gauge; the strain accuracy of the target strain value is obtained according to the initial setting fluctuation difference and stability trend of the target strain value; According to the change of the strain accuracy of the strain value in the strain monitoring sequence of the target concrete strain gauge, the formation start time of the target concrete strain gauge is obtained; according to the difference relationship between the formation start time of the target concrete strain gauge and other concrete strain gauges, the solidification corresponding time of the target strain value in the strain monitoring sequence of each concrete strain gauge is obtained; According to the continuous increase of the strain value of the target strain value at the corresponding moment of solidification in the strain monitoring sequence of all concrete strain gauges, the risk index of the target strain value is obtained; According to the risk index of the target strain value, the real-time early warning results of underground engineering construction safety risks are obtained.

2. According to the method of claim 1, the method is characterized in that: The initial setting fluctuation difference of the target strain value is obtained according to the fluctuation difference relationship between the target strain value and the strain value in the strain monitoring sequence of the target concrete strain gauge, and the specific method includes: The length of the target strain value is constructed as The window is recorded as the adjacent window of the target strain value; The variance of all strain values ​​within the window adjacent to the target strain value is recorded as the adjacent fluctuation index of the target strain value; where is the preset window length; According to the difference of the adjacent fluctuation index of the strain value in the strain monitoring sequence of the target concrete strain gauge, the initial setting fluctuation difference of the target strain value is obtained.

3. According to claim 2, a real-time early warning method for underground engineering construction safety risks based on the Internet of Things is characterized in that: The specific method of obtaining the initial setting fluctuation difference of the target strain value according to the difference of the adjacent fluctuation index of the strain value in the strain monitoring sequence of the target concrete strain gauge includes: The average value of the proximity fluctuation index of all strain values ​​within the proximity window of the target strain value is obtained, and the difference obtained by subtracting the average value from the maximum value of the proximity fluctuation index of all strain values ​​monitored by the target concrete strain gauge is recorded as the initial setting fluctuation difference of the target strain value.

4. According to claim 2, a real-time early warning method for underground engineering construction safety risks based on the Internet of Things is characterized in that: According to the fluctuation stability trend of the strain value in the strain monitoring sequence of the target concrete strain gauge, the stability trend of the target strain value is obtained. The specific acquisition method is: In the formula, is the stable trend of the target strain value; The first in the strain monitoring sequence of the target concrete strain gauge The adjacent fluctuation index of the strain value; The first in the strain monitoring sequence of the target concrete strain gauge The adjacent fluctuation index of the strain value; is the ordinal number of the target strain value in the strain monitoring sequence of the target concrete strain gauge; is the absolute value function.

5. The method for real-time early warning of underground engineering construction safety risks based on the Internet of Things according to claim 1 is characterized in that: The method of obtaining the strain accuracy of the target strain value according to the initial setting fluctuation difference and the stability trend of the target strain value includes the following specific methods: The product of the initial setting fluctuation difference and the stability trend of the target strain value is taken as the strain accuracy of the target strain value.

6. The method for real-time early warning of underground engineering construction safety risks based on the Internet of Things according to claim 1 is characterized in that: The specific method of obtaining the formation start time of the target concrete strain gauge according to the change of the strain accuracy of the strain value in the strain monitoring sequence of the target concrete strain gauge includes: The difference between the strain accuracy of the target strain value and the strain accuracy of the previous strain value is recorded as the stage change degree of the target strain value; The time at which the strain value with the largest stage change degree in the strain monitoring sequence of the target concrete strain gauge is located is recorded as the formation start time of the target concrete strain gauge.

7. The method for real-time early warning of underground engineering construction safety risks based on the Internet of Things according to claim 1 is characterized in that: The specific method of obtaining the solidification corresponding time of the target strain value in the strain monitoring sequence of each concrete strain gauge according to the difference relationship between the formation start time of the target concrete strain gauge and other concrete strain gauges is as follows: In the formula, The target strain value is The solidification corresponding moment in the strain monitoring sequence of the concrete strain gauge; For the The formation start time of each concrete strain gauge; is the formation start time of the target concrete strain gauge; is the ordinal number of the target strain value in the strain monitoring sequence of the target concrete strain gauge; is the floor function.

8. The method for real-time early warning of underground engineering construction safety risks based on the Internet of Things according to claim 1 is characterized in that: The risk index of the target strain value is obtained according to the continuous increase of the strain value of the target strain value at the corresponding time of solidification in the strain monitoring sequence of all concrete strain gauges, including the specific method of: The difference obtained by subtracting the strain value of the target strain value at the corresponding solidification time of the previous concrete strain gauge of the target concrete strain gauge from the target strain value is recorded as the change of the target strain value; The calculation method of the change increase index of the target strain value is: In the formula, Increase the exponent for the change in target strain value; is the change in target strain value; is the change in the strain value of the target strain value at the corresponding moment of solidification of the previous concrete strain gauge of the target concrete strain gauge; is the absolute value function; According to the continuous increase of the strain value of the target strain value at the solidification corresponding moment in the strain monitoring sequence of all concrete strain gauges, the risk index of the target strain value is obtained.

9. The method for real-time early warning of underground engineering construction safety risks based on the Internet of Things according to claim 8 is characterized in that: The risk index of the target strain value is obtained according to the continuous increase of the strain value of the target strain value at the corresponding time of solidification in the strain monitoring sequence of all concrete strain gauges, including the specific method of: In the formula, is the risk index of the target strain value; For the The minimum value of the increase index of the change of the strain value of the target strain value at the corresponding moment of solidification among all the concrete strain gauges from the concrete strain gauge to the target concrete strain gauge; The target strain value is The change increase index of the strain value corresponding to the solidification moment in the concrete strain gauge; is the total number of concrete strain gauges installed.

10. The method for real-time early warning of underground engineering construction safety risks based on the Internet of Things according to claim 1, characterized in that: The real-time early warning result of underground engineering construction safety risk is obtained according to the risk index of the target strain value. The specific acquisition method is: If the risk index of the target strain value is greater than the preset risk threshold, there is a risk of collapse.

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