A tunnel concrete shotcrete rapid hardening agent control method and system, and a computer device

Abstract

The application belongs to the technical field of tunnel construction, and particularly relates to a tunnel concrete spraying rapid hardening agent control method and system and a computer device. The method first acquires a real-time position of a spraying head for spraying in a tunnel, determines a basic proportion of a rapid hardening agent corresponding to the real-time position according to a preset corresponding relationship between different positions of the tunnel considering different gravity component forces and the basic proportion of the rapid hardening agent, simultaneously acquires real-time environmental factors in the tunnel affecting a concrete setting time, determines an adjustment proportion of the rapid hardening agent corresponding to the real-time environmental factors according to a preset corresponding relationship between different environmental factors and the adjustment proportion of the rapid hardening agent, and finally adjusts the determined basic proportion of the rapid hardening agent according to the determined adjustment proportion of the rapid hardening agent, and controls a rapid hardening agent adding device according to the adjusted proportion. The application fully considers the influence of gravity component forces at different positions of the tunnel and environmental factors in the tunnel affecting the concrete setting time on the proportion of the rapid hardening agent, so that the added rapid hardening agent is more scientific and reasonable.

Description

Technical Field

[0001] This invention belongs to the field of tunnel construction technology, specifically relating to a method and system for controlling the quick-setting agent of tunnel concrete spraying, and computer equipment. Background Technology

[0002] With the rapid development of transportation infrastructure construction, the number of tunnel projects is constantly increasing. In the initial support of tunnels, shotcrete is a key construction technique that can quickly provide support to the surrounding rock, prevent further deformation and collapse of the surrounding rock, ensure the safety of tunnel construction, and create favorable conditions for subsequent construction.

[0003] During tunnel excavation, initial support with shotcrete is a crucial step in ensuring tunnel stability. Due to the shape of circular tunnels, the gravitational force varies at different locations, affecting the setting characteristics of the concrete. Simultaneously, varying temperature and humidity levels within the tunnel significantly impact the effectiveness of accelerators. Accelerators, as admixtures capable of significantly altering the setting properties of concrete, are widely used in shotcrete construction for tunnels.

[0004] However, in practical applications of tunnel initial support, there is a lack of precise and systematic guidelines for determining the proportion of accelerators. Accelerators are often added on-site based on experience, a method with numerous drawbacks. Traditional shotcrete construction often uses a fixed proportion of accelerators, which cannot adapt to changes in different tunnel locations and environmental conditions, easily leading to unreasonable concrete setting times and affecting support effectiveness and construction quality. For example, localized excessively rapid concrete setting may result in insufficient strength, while excessively slow setting may hinder construction progress. In tunnel sections with soft surrounding rock and high water permeability, a higher proportion of accelerators may be needed to achieve rapid setting and early strength improvement, but an excessively high proportion may lead to insufficient later-stage concrete strength and reduced durability. In tunnel sections with relatively stable and dry surrounding rock, an excessively high proportion of accelerators is completely unnecessary, only increasing construction costs and potentially negatively impacting concrete performance.

[0005] Chinese invention patent application CN116241279A, published on June 9, 2023, discloses a method for controlling the linkage of accelerator in a wet spraying machine. In this method, the accelerator consumption is the product of cement consumption and the optimal accelerator dosage ratio. The optimal accelerator dosage ratio is obtained by the operator through testing to determine the optimal dosage ratio, and then fine-tuning it based on the actual on-site construction conditions. This method mentions the need to adjust the tested dosage ratio according to on-site conditions, but it does not provide specific methods for this adjustment. Summary of the Invention

[0006] The purpose of this invention is to provide a method and system for controlling the accelerator of shotcrete in tunnel concrete, as well as a computer device, to solve the problem of insufficient concrete strength or slow setting caused by an unsuitable proportion of accelerator determined by existing methods.

[0007] To address the aforementioned technical problems, this invention provides a method for controlling the accelerator in tunnel concrete spraying. The method includes: acquiring the real-time position of the spraying nozzle in the tunnel; determining the accelerator base ratio corresponding to the real-time position based on a preset correspondence between different tunnel positions considering different gravitational components and the accelerator base ratio; acquiring real-time environmental factors affecting the concrete setting time within the tunnel; determining the accelerator adjustment ratio corresponding to the real-time environmental factors based on a preset correspondence between different environmental factors and the accelerator adjustment ratio; adjusting the determined accelerator base ratio according to the determined accelerator adjustment ratio; and controlling the accelerator addition device according to the adjusted ratio.

[0008] Furthermore, the pre-defined correspondence between different locations of the tunnel and the proportion of accelerator base material, considering different gravity components, includes: the tunnel is divided into a tunnel top area and two bottom areas on both sides of the tunnel, excluding the tunnel top area, and the proportion of accelerator base material in the tunnel top area is higher than that in the bottom areas on both sides of the tunnel.

[0009] Furthermore, the environmental factors include temperature and humidity.

[0010] Furthermore, the preset relationship between environmental factors and the accelerator adjustment ratio is that one humidity range and one temperature range correspond to one accelerator adjustment ratio.

[0011] To address the aforementioned technical problems, the present invention also provides a computer device, including a processor, which executes a computer program to implement the steps of the tunnel concrete spraying accelerator control method described above.

[0012] To address the aforementioned technical problems, this invention also provides a tunnel concrete shotcrete accelerator control system, comprising a position detection module, an environmental factor detection module, a storage module, and a control module. The position detection module detects the real-time position of the shotcrete nozzle in the tunnel; the environmental factor detection module detects real-time environmental factors affecting the concrete setting time within the tunnel; the storage module stores the correspondence between different tunnel positions considering different gravity components and the accelerator base ratio, as well as the correspondence between different environmental factors and the accelerator adjustment ratio. The control module, based on the information detected by the position detection module and the environmental factor detection module, retrieves the accelerator base ratio corresponding to the real-time position and the accelerator adjustment ratio corresponding to the real-time environmental factors from the storage module, adjusts the accelerator base ratio according to the adjustment ratio, and controls the accelerator addition device based on the adjusted ratio.

[0013] Furthermore, the pre-defined correspondence between different locations of the tunnel and the proportion of accelerator base material, considering different gravity components, includes: the tunnel is divided into a tunnel top area and two bottom areas on both sides of the tunnel, excluding the tunnel top area, and the proportion of accelerator base material in the tunnel top area is higher than that in the bottom areas on both sides of the tunnel.

[0014] Furthermore, the environmental factors include temperature and humidity.

[0015] Furthermore, the preset relationship between environmental factors and the accelerator adjustment ratio is that one humidity range and one temperature range correspond to one accelerator adjustment ratio.

[0016] Furthermore, the position detection module is an angle sensor installed on the nozzle or a detection module including a rangefinder and a gyroscope, wherein the rangefinder is used to measure the distance between the nozzle and a fixed reference point inside the tunnel.

[0017] This invention is a pioneering invention with the following beneficial effects: It provides a novel method for determining the optimal ratio of accelerators. Specifically, it fully considers the differences in the gravitational force at different locations within the tunnel, which have varying impacts on the setting characteristics of concrete, and the significant influence of environmental factors within the tunnel on the accelerator's effectiveness. Two pre-defined relationships are established: one between different tunnel locations and the basic accelerator ratio, and the other between different environmental factors and the accelerator adjustment ratio. By obtaining the real-time location of the nozzle within the tunnel and the real-time environmental factors, the corresponding basic and adjustment ratios of the accelerator can be calculated based on these two pre-defined relationships. These ratios are then used to determine the precise accelerator control ratio, enabling adaptive adjustment of the accelerator based on the nozzle's location and environmental changes within the tunnel. This ensures a more scientific and rational addition of accelerator, preventing excessive addition that increases costs and negatively impacts concrete durability, and avoiding insufficient addition that hinders construction progress. This effectively improves the quality and effectiveness of shotcrete support. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the shotcrete support of the present invention;

[0019] Figure 2 This is a schematic diagram of the nozzle structure of the present invention;

[0020] Figure 3 This is a structural diagram of the tunnel concrete spraying accelerator control system of the present invention;

[0021] Figure 4 This is a schematic diagram of the tunnel interface of the present invention.

[0022] Among them, 1. Tunnel face to be supported, 2. Nozzle drive assembly, 3. Nozzle, 4. Ring gear track, 5. Forward and backward moving gear track, 31. Fixing plate, 32. Four-way connector, 33. Nozzle, 34. Mixer, 35. Angle sensor. Detailed Implementation

[0023] The main concept of this invention is to fully consider the influence of gravity, temperature, and humidity at different locations in the tunnel on the proportion of accelerator. Two relationships are established: the correspondence between different tunnel locations and the basic accelerator proportion, and the correspondence between different environmental factors and the accelerator adjustment proportion. Based on these two relationships, the basic accelerator proportion corresponding to the real-time position of the nozzle in the tunnel and the accelerator adjustment proportion corresponding to the real-time environmental factors within the tunnel are obtained. The obtained accelerator adjustment proportion is then used to adjust the basic accelerator proportion. The accelerator addition device is controlled according to the adjusted proportion, thereby achieving scientific and rational addition of accelerator and effectively improving the quality and effect of shotcrete support. Based on this concept, a tunnel concrete shotcrete accelerator control method, a computer device, and a tunnel concrete shotcrete accelerator control system can be realized. To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] An embodiment of a tunnel concrete shotcrete quick-setting agent control system:

[0025] like Figure 1 The diagram shows the overall structure of shotcrete support, mainly composed of the tunnel face to be supported 1, a nozzle drive assembly 2, a nozzle 3, a ring gear track 4, and a forward and backward moving gear track 5. The nozzle 3 is bolted to the nozzle drive assembly 2, which can move along the ring gear track 4. Figure 2The diagram shows the structure of the nozzle 3. The nozzle 3 consists of a fixed plate 31, a four-way connector 32, a nozzle 33, a mixer 34, and an angle sensor 35. The three ports on the nozzle 3 (ports A, B, and C) are connected to the delivery pump, the accelerator pump, and the air compressor, respectively. An angle sensor 35 is installed on the fixed plate 31 of the nozzle 3. As the nozzle 3 moves along the ring gear track 4, the tilt angle of the fixed plate 31 is constantly detected. Based on the tilt angle and the known distance from the center of the cross-section, the position of the nozzle 3 on the ring gear track 4 can be calculated in real time, thus determining the nozzle's position in the tunnel. In addition to the angle sensor 35, other types of sensors can be added to the nozzle assembly 3 to detect the nozzle's position on the ring gear track. For example, a combination of a rangefinder (e.g., a laser rangefinder) and a gyroscope can be used. The laser rangefinder measures the distance between the nozzle and a fixed reference point in the tunnel, while the gyroscope measures the nozzle's angle, thereby determining the nozzle's precise position in the tunnel. Furthermore, an environmental factor detection device is installed in the shotcrete operation area. This device is specifically used to detect environmental factors that affect the setting time of concrete in the tunnel. Considering that temperature and humidity have a significant impact on the effect of accelerators, the environmental factors considered in this embodiment are temperature and humidity. The corresponding environmental factor detection device is a temperature and humidity detection device. The temperature and humidity detection device uses multiple sensor nodes evenly distributed in the tunnel, such as setting one node every 2 meters. The sensor nodes collect the temperature and humidity data of the surrounding environment in real time and transmit the data to the control module wirelessly.

[0026] Based on the above description, the tunnel concrete spraying accelerator control system of the present invention includes a position detection module, an environmental factor detection module, a storage module, and a control module, etc., with specific connections as follows: Figure 3 As shown. The position detection module specifically includes an angle sensor, used to collect the nozzle position information in real time and transmit it to the control module. The environmental factor detection module specifically selects a temperature and humidity detection module, which includes multiple temperature and humidity sensor nodes and a wireless transmission unit. The temperature and humidity sensor nodes are distributed inside the tunnel, collecting temperature and humidity data near the shotcrete operation area and transmitting it to the control module via the wireless transmission unit. The storage module is specifically a database storage module, which uses a read-write storage medium for data updates and management, such as a hard disk or solid-state drive. It stores a database of the correspondence between different tunnel locations and the basic ratio of accelerator, as well as an adjustment ratio database for accelerator under different temperature and humidity conditions. The control module, as the core of the entire system, receives information transmitted from the position detection module and the temperature and humidity detection module, retrieves the corresponding data from the database storage module for calculation, obtains the final precise control ratio of accelerator, and sends control commands to the accelerator addition device.

[0027] The process involves dividing the tunnel into two or more circumferential regions. Based on mechanical principles and combined with past engineering experience data, a database is established to map the relationship between the proportion of accelerator-based materials and the actual weight distribution under different gravitational forces in each region. For example, the tunnel can be divided into two regions: the tunnel top region and the bottom regions on both sides of the tunnel (excluding the top region). The tunnel top region, with its higher gravitational force, has a relatively higher proportion of accelerator-based materials, while the bottom regions on both sides have a lower proportion due to the lower gravitational force. More detailed regional divisions can also be implemented, such as adding a layer between the tunnel top and bottom regions to create a tunnel top region, a tunnel middle region, and a tunnel bottom region. Correspondingly, the tunnel top region would have the highest proportion of accelerator-based materials, the middle region a moderate proportion, and the bottom region a relatively low proportion.

[0028] Simultaneously, numerous concrete spraying experiments were conducted in the laboratory under varying temperature and humidity conditions to record the optimal adjustment ratio of the accelerator under different conditions, establishing a database of adjustment ratios for temperature, humidity, and accelerator. The final database can be structured as follows: one humidity range corresponds to one accelerator adjustment ratio, which integrates temperature and humidity factors; or one temperature range corresponds to one accelerator adjustment ratio, and one humidity range corresponds to one accelerator adjustment ratio. The final accelerator adjustment ratios corresponding to temperature and humidity are obtained by combining the temperature-corresponding and humidity-corresponding ratios (e.g., by direct addition), which decouples the consideration of temperature and humidity factors. The relationship between the accelerator adjustment ratio and temperature and humidity is as follows: With other factors remaining constant, as temperature increases, the hydration reaction rate of concrete accelerates, and the accelerator adjustment ratio decreases. However, after a certain temperature increase, the accelerator adjustment ratio no longer changes. In low-humidity environments, the moisture in concrete evaporates quickly, affecting cement hydration. That is, with other factors remaining constant, as humidity increases, the accelerator adjustment ratio decreases. Once the humidity exceeds a certain value, humidity no longer affects the accelerator adjustment ratio.

[0029] Furthermore, throughout the construction process, the corresponding relationship database and the adjustment ratio database can be updated and optimized in real time based on new engineering practice data and experimental results. For example, if it is found in a certain project that the original accelerator ratio setting is not effective under certain special geological conditions, the corresponding data in the database can be corrected by analyzing the actual monitoring data and concrete performance test results of the area, so that the accelerator ratio can be controlled more accurately in subsequent similar projects.

[0030] Based on the above system, a method for controlling the quick-setting agent of tunnel concrete spraying grout according to the present invention can be implemented, the specific process of which is as follows:

[0031] 1) During the shotcrete operation, the position detection module and the temperature and humidity detection module work continuously, transmitting the real-time position information of the nozzle and the real-time environmental factor information (specifically including real-time temperature information and real-time humidity information) to the control module without interruption.

[0032] 2) After receiving the information, the control module first looks up the basic ratio of the accelerator corresponding to the area of ​​the real-time location in the corresponding relational database according to the nozzle position; then, based on the temperature and humidity information, it obtains the accelerator adjustment ratio corresponding to the real-time temperature and humidity from the adjustment ratio database; finally, it adjusts the basic ratio of the accelerator according to the accelerator adjustment ratio to obtain the final accelerator control ratio, and sends the feedback signal of the final accelerator ratio to the frequency converter, so that the frequency converter controls the speed of the accelerator pump, thereby realizing precise control of the accelerator ratio.

[0033] For example, if the current nozzle is located at the top of the tunnel, and the basic proportion of the accelerator obtained from the relational data is 9%, and the temperature inside the tunnel is 20℃ and the humidity is 70%, the adjustment proportion corresponding to the temperature and humidity is found to be -0.5% from the adjustment proportion database (indicating that the proportion of accelerator needs to be reduced); the control module calculates based on the basic proportion of the accelerator and the adjustment proportion of the accelerator, i.e., 9% + (-0.5%) = 9%, and obtains the final control proportion of the accelerator as 9%. Based on this proportion, the control module sends a control command to the accelerator adding device, and the accelerator adding device accurately adds the accelerator to the concrete according to the command.

[0034] The following is combined with Figure 4 The present invention is described below. When the nozzle 3 is at position A at the top of the tunnel, and the ambient temperature, humidity, and concrete ratio are determined, the proportion of quick-setting agent added is related to the position of the nozzle 3 on the ring gear track 4. As the nozzle 3 moves from position A to position B1, the proportion of quick-setting agent gradually decreases and then remains constant after reaching a certain value. As the nozzle 3 returns from position B1 to position A, the proportion of quick-setting agent remains constant at first, then gradually increases after reaching a certain position. When it reaches position A, the proportion of quick-setting agent reaches its maximum. The process of the nozzle 3 moving from position A to position B2 and from position B2 to position A corresponds to the proportion of quick-setting agent moving from A to B1 and from B1 to A.

[0035] An embodiment of a computer device:

[0036] An embodiment of a computer device according to the present invention includes a memory, a processor, an internal bus, and a computer program stored in the memory. The processor and the memory communicate and interact with each other via the internal bus. The processor executes the computer program to implement the steps of the tunnel concrete spraying accelerator control method described in an embodiment of the present invention. The processor can be a microprocessor (MCU), a programmable logic device (FPGA), or other processing devices; the memory can be various types of memory that store information using electrical energy, such as RAM or ROM, or other types of memory.

[0037] An example of a method for controlling the setting of quick-setting agents in tunnel concrete spraying:

[0038] An embodiment of the method for controlling the quick-setting agent of tunnel concrete shotcrete according to the present invention, which can be based on Figure 3 The control system is implemented by determining the basic ratio of the accelerator based on the real-time position of the nozzle in the tunnel, and then determining the adjustment ratio of the accelerator based on real-time environmental factors within the tunnel. The basic ratio of the accelerator is then adjusted according to this adjustment ratio, and the accelerator addition device is controlled based on the adjusted ratio. This achieves adaptive adjustment of the accelerator according to different nozzle positions and environmental changes within the tunnel. The specific principles and implementation process of this method have been detailed in an embodiment of a tunnel concrete spraying accelerator control system, and will not be repeated here.

[0039] In summary, this invention has the following characteristics: By installing position detection devices and temperature and humidity detection devices inside the tunnel, this invention can acquire real-time information on the nozzle position and the tunnel environment, providing a data foundation for precise control of the accelerator ratio; the established correspondence database and adjustment ratio database fully consider the influence of gravity components and environmental factors (temperature and humidity) on the accelerator ratio at different locations in the tunnel, adaptively adjusting the accelerator ratio to make the addition of accelerator more scientific and reasonable, effectively improving the quality and effect of concrete shotcrete support; moreover, the entire system can continuously update and optimize the database according to actual engineering conditions, has strong adaptability, and can be widely applied to tunnel construction under different geological conditions and environments.

[0040] Specific implementation methods have been given above, but the present invention is not limited to the described implementation methods. The basic idea of ​​the present invention lies in the above basic scheme. For those skilled in the art, designing various modified models, formulas, and parameters based on the teachings of the present invention does not require creative effort. Changes, modifications, substitutions, and variations made to the implementation methods without departing from the principles and spirit of the present invention still fall within the protection scope of the present invention.

Claims

1. A method for controlling the setting of quick-setting agent in tunnel concrete spraying, characterized in that, The method includes: The real-time position of the shotcrete nozzle in the tunnel is obtained. Based on the preset correspondence between different positions in the tunnel with different gravity components and the proportion of accelerator base, the proportion of accelerator base corresponding to the real-time position is determined. The tunnel is divided into two or more areas according to the position. The proportion of accelerator base in the area with a large gravity component is greater than that in the area with a small gravity component. Real-time environmental factors, including temperature and humidity, that affect the setting time of concrete inside the tunnel are obtained. Based on the preset relationship between different environmental factors and the adjustment ratio of accelerator, the adjustment ratio of accelerator corresponding to the real-time environmental factors is determined. The preset relationship between environmental factors and the adjustment ratio of accelerator is that one humidity range and one temperature range correspond to one adjustment ratio of accelerator. The determined base ratio of the accelerator is adjusted according to the determined adjustment ratio, and the accelerator addition device is controlled according to the adjusted ratio.

2. The method for controlling the quick-setting agent of tunnel concrete shotcrete according to claim 1, characterized in that, The tunnel is divided into two areas based on its location: the tunnel top area and the bottom areas on both sides of the tunnel excluding the tunnel top area. The proportion of accelerator base in the tunnel top area is higher than that in the bottom areas on both sides of the tunnel.

3. The method for controlling the quick-setting agent of tunnel concrete shotcrete according to claim 1, characterized in that, The real-time position of the shotcrete nozzle in the tunnel is obtained by an angle sensor installed on the nozzle or a detection module including a rangefinder and a gyroscope. The rangefinder is used to measure the distance between the nozzle and a fixed reference point in the tunnel.

4. The method for controlling the quick-setting agent of tunnel concrete shotcrete according to claim 1, characterized in that, The relationship between different environmental factors and the adjustment ratio of accelerators was obtained by conducting concrete spraying experiments under different temperature and humidity conditions.

5. A computer device, comprising a processor, characterized in that, The processor is used to execute a computer program to implement the steps of the method according to any one of claims 1 to 4.

6. A control system for a tunnel concrete spraying accelerator, characterized in that, It includes a location detection module, an environmental factor detection module, a storage module, and a control module; The location detection module is used to detect the real-time position of the shotcrete nozzle in the tunnel. The environmental factor detection module is used to detect real-time environmental factors, including temperature and humidity, that affect the concrete setting time in the tunnel. The storage module stores the correspondence between different locations in the tunnel with different gravity components and the proportion of accelerator base, as well as the correspondence between different environmental factors and the adjustment ratio of accelerator. The tunnel is divided into two or more areas according to its location. The proportion of accelerator base in the area with a larger gravity component is greater than that in the area with a smaller gravity component. The preset correspondence between environmental factors and the adjustment ratio of accelerator is one humidity range and one temperature range corresponding to one adjustment ratio of accelerator. The control module is used to retrieve the basic ratio of accelerator corresponding to the real-time location and the adjustment ratio of accelerator corresponding to the real-time environmental factors from the storage module based on the information detected by the location detection module and the environmental factor detection module. It then adjusts the basic ratio of accelerator according to the adjustment ratio and controls the accelerator addition device according to the adjusted ratio.

7. The tunnel concrete spraying accelerator control system according to claim 6, characterized in that, The tunnel is divided into two areas based on its location: the tunnel top area and the bottom areas on both sides of the tunnel excluding the tunnel top area. The proportion of accelerator base in the tunnel top area is higher than that in the bottom areas on both sides of the tunnel.

8. The tunnel concrete spraying accelerator control system according to claim 6, characterized in that, The relationship between different environmental factors and the adjustment ratio of accelerators was obtained by conducting concrete spraying experiments under different temperature and humidity conditions.

9. The tunnel concrete spraying accelerator control system according to claim 6, characterized in that, The storage module includes a database for storing the correspondence between different locations of the tunnel considering different gravity components and the base ratio of the accelerator, and an adjustment ratio database for storing the correspondence between different environmental factors and the adjustment ratio of the accelerator.

10. The tunnel concrete spraying accelerator control system according to any one of claims 6 to 9, characterized in that, The position detection module is an angle sensor installed on the nozzle or a detection module including a rangefinder and a gyroscope. The rangefinder is used to measure the distance between the nozzle and a fixed reference point inside the tunnel.

Images