An intelligent monitoring and repairing system for self-repairing concrete cracks and a construction method thereof
By combining intelligent aggregates, sensor monitoring networks, and electrode units, an intelligent monitoring and repair system has been developed to solve the problem of real-time monitoring and efficient repair of concrete cracks, achieving efficient automatic repair and improved durability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- FOSHAN UNIVERSITY
- Filing Date
- 2026-03-10
- Publication Date
- 2026-06-05
AI Technical Summary
Existing technologies struggle to detect concrete cracks in real time and achieve efficient automatic repair. Traditional repair methods are inefficient and lack durability, resulting in a disconnect between monitoring and repair functions.
By combining intelligent aggregate unit, sensor monitoring network unit, electrode unit and control unit, strain is monitored by fiber optic grating sensor, damaged area is located and shape memory alloy fiber is activated to release repair agent to achieve automatic repair.
It enables real-time monitoring and efficient repair of cracks, with a repair rate of over 90%, improved durability, reduced maintenance costs, and fewer major repairs.
Smart Images
Figure CN122148087A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of concrete crack repair technology, specifically to an intelligent monitoring and repair system and construction method for self-healing concrete cracks. Background Technology
[0002] Concrete, due to its high compressive strength, good durability, and wide availability of raw materials, has become the most widely used building material in the world. However, due to its inherently low tensile strength, concrete structures are highly susceptible to cracking under load, temperature changes, shrinkage, and creep. Cracks are the starting point of structural aging, not only affecting aesthetics but also providing pathways for the intrusion of harmful substances such as moisture and chloride ions, accelerating the corrosion of internal steel reinforcement and the deterioration of concrete, severely impairing the structure's load-bearing capacity and durability, and ultimately threatening overall safety.
[0003] The maintenance of concrete cracks has long relied on the traditional model of "passive discovery and manual intervention." This model has inherent drawbacks: First, the initiation and development of cracks are difficult to detect in real time, relying on periodic inspections, and by the time they are discovered, the structure may have already accumulated irreversible damage; traditional repair methods such as grouting and surface sealing are inefficient and costly, and have limited effectiveness in repairing internal or micro-cracks. Self-healing concrete uses microcapsules containing repair agents pre-embedded in the concrete, which rupture and release the repair agent when the crack expands to achieve automatic repair. However, its repair capacity is limited, usually only able to repair micro-cracks less than 0.3 mm wide; microcapsules are disposable consumables and cannot cope with repeated cracking in the same location, resulting in insufficient durability.
[0004] Currently, common advanced monitoring technologies such as fiber optic sensing have been tried in concrete health monitoring, which can detect cracks. However, manual repair is still required after the fiber optic sensor has detected the cracks, resulting in a disconnect between monitoring and repair functions. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this invention provides an intelligent monitoring and repair system and construction method for self-healing concrete cracks, solving the problems mentioned in the background.
[0006] This invention provides the following technical solution: an intelligent monitoring and repair system for self-healing concrete cracks, comprising: The intelligent aggregate unit is embedded in the concrete structure. The intelligent aggregate unit includes basalt aggregate and embedded microcapsules and shape memory alloy fibers encapsulated inside it. A sensing and monitoring network unit is embedded in the concrete structure to monitor the strain signal of the concrete structure in real time. The sensing and monitoring network is a fiber optic grating sensor matrix. Electrode units are placed on the surface or inside a designated area of a concrete structure to generate heat when energized. A control unit, electrically connected to the sensing and monitoring network and the electrode unit, is configured to: receive and analyze strain signals transmitted from the sensing and monitoring network, and when the strain signal exceeds a preset threshold, control the supply of power to the electrode unit in the damaged area, so as to activate the shape memory alloy fiber in the area to shrink through electrothermal effect and cause the embedded microcapsule to rupture and release the repair agent.
[0007] Preferably, in the intelligent aggregate unit, the basalt aggregate has a particle size of 15-25 mm; the embedded microcapsules have a particle size of 100-300 mm. m; The shape memory alloy fiber is a NiTiNol alloy fiber with a diameter of 0.2 mm.
[0008] Preferably, the fiber Bragg grating sensors in the sensing and monitoring network are arranged in a grid pattern with a longitudinal and transverse spacing of 200 mm, and the monitoring accuracy range is ± .
[0009] Preferably, the electrode system is a carbon nanotube coating or a conductive concrete coating applied to the concrete surface, wherein the resistivity of the carbon nanotube coating or the conductive concrete coating is less than [value missing]. The coating thickness of the carbon nanotube coating or conductive concrete coating is 1 mm.
[0010] Preferably, the control system is configured to establish a strain-temperature mapping model: ; in The activation threshold is set when the detected strain value continuously exceeds [a certain threshold]. Continue for 5 minutes.
[0011] Preferably, the control unit is further configured to: analyze and locate the coordinates of the area where the concrete structure is damaged based on the signals transmitted from the sensor monitoring network; Repair process initiated: Crack occurs → Fiber optic grating sensor monitors strain mutation → Control center analyzes and locates → Electrode in damaged area is activated → Electrothermal stimulation of shape memory alloy fiber shrinkage → Embedded microcapsule ruptures and releases repair agent → Dual repair completed.
[0012] Preferably, the location of the damaged region is based on the wavelength shift of the fiber grating. The wavelength shift is calculated according to the formula: ; in It is the strain coefficient. It is the temperature coefficient. It is about adapting to change. It's a temperature change.
[0013] A construction method for self-healing concrete cracks includes the following steps: Step S1, Pre-fabrication of intelligent aggregates: After mixing the embedded microcapsules with shape memory alloy fibers, the mixture was injected into the pores of basalt aggregate and sealed with epoxy resin, and then cured at 80°C for 2 hours. Step S2, concrete pouring: The prefabricated intelligent aggregate unit is mixed into the concrete at a dosage of 3-5% of the concrete volume and then poured. During the pouring process, fiber optic grating sensor matrix is embedded in layers, with the fiber optic grating sensors arranged in a grid pattern with a longitudinal and transverse spacing of 200mm. A carbon nanotube coating or a conductive concrete coating is applied to the surface of a concrete structure as an electrode system, with the coating thickness controlled to be 1 mm. Step S3, Control System Deployment: The sensing network and the electrode system are connected to the control system, and a strain-temperature mapping model is established within the control system. ,in The activation threshold is set when the detected strain value continuously exceeds [a certain threshold]. Continue for 5 minutes.
[0014] Preferably, the intelligent aggregate unit is added to the concrete structure at a dosage of 3-5% of the concrete volume.
[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention utilizes the cooperation of an intelligent aggregate unit, a sensing and monitoring network unit, an electrode unit, and a control unit. After a crack occurs, a fiber optic grating sensor monitors the sudden change in strain. The control center analyzes and locates the crack, activates the electrode in the damaged area, and electrothermally excites the shape memory alloy fiber to shrink. At the same time, the embedded microcapsules rupture and release a repair agent, forming a complete intelligent response closed loop. This solves the problem of the disconnect between monitoring and repair. Furthermore, the shape memory alloy fiber and the embedded microcapsules work together to perform dual repair, improving the repair rate. Attached Figure Description
[0016] Figure 1 This is a diagram illustrating the architecture of the intelligent monitoring and repair system for self-healing concrete cracks according to the present invention. Figure 2 This is a flowchart illustrating the repair process of the present invention; Figure 3 This is a flowchart of the construction method for the self-healing concrete cracks of the present invention; Figure 4This is a schematic diagram of the intelligent aggregate structure of the present invention. Detailed Implementation
[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0018] Please see Figure 1-3 A smart monitoring and repair system for self-healing concrete cracks, comprising: The intelligent aggregate unit is embedded in the concrete structure. The intelligent aggregate unit includes basalt aggregate and embedded microcapsules and shape memory alloy fibers encapsulated inside it. A sensing and monitoring network unit is embedded in the concrete structure to monitor the strain signal of the concrete structure in real time. The sensing and monitoring network is a fiber optic grating sensor matrix. Electrode units are placed on the surface or inside a designated area of a concrete structure to generate heat when energized. A control unit, electrically connected to the sensing and monitoring network and the electrode unit, is configured to: receive and analyze strain signals transmitted from the sensing and monitoring network, and when the strain signal exceeds a preset threshold, control the supply of power to the electrode unit in the damaged area, so as to activate the shape memory alloy fiber in the area to shrink through electrothermal effect and cause the embedded microcapsule to rupture and release the repair agent.
[0019] In the intelligent aggregate unit, the basalt aggregate has a particle size of 15-25 mm; the embedded microcapsules have a particle size of 100-300 mm. m; The shape memory alloy fiber is a NiTiNol alloy fiber with a diameter of 0.2mm. The instantaneous electrothermal shrinkage force of the shape memory alloy fiber enables rapid closure of macroscopic cracks. Combined with the long-term sealing of the microcapsule repair agent, the width of a single repair is increased from the traditional <0.3mm to more than 0.8mm. The shape memory alloy fiber can be repeatedly activated to cope with repeated cracking at the same location. It has been verified that the number of repeated cracking resistances is increased by 3 times, which greatly improves the durability of the structure. The shape memory alloy fiber and the embedded microcapsule work together for dual repair, resulting in an overall repair rate of more than 90%, with significant and reliable repair effects.
[0020] The fiber Bragg grating sensors in the sensing and monitoring network are arranged in a grid pattern with a longitudinal and transverse spacing of 200 mm, and the monitoring accuracy range is ± .
[0021] The electrode system is a carbon nanotube coating or a conductive concrete coating applied to the concrete surface, wherein the resistivity of the carbon nanotube coating or the conductive concrete coating is less than [value missing]. The coating thickness of the carbon nanotube coating or conductive concrete coating is 1 mm.
[0022] The control system is configured to establish a strain-temperature mapping model: ; in The activation threshold is set when the detected strain value continuously exceeds [a certain threshold]. Continue for 5 minutes.
[0023] Please see Figure 2 The control unit is also configured to: analyze and locate the coordinates of the area where the concrete structure is damaged based on the signals transmitted from the sensor monitoring network; Repair process initiated: Crack occurs → Fiber optic grating sensor monitors strain mutation → Control center analyzes and locates → Electrode in damaged area is activated → Electrothermal stimulation of shape memory alloy fiber shrinkage → Embedded microcapsule ruptures and releases repair agent → Dual repair completed; A fiber optic grating sensor matrix embedded in a concrete structure monitors strain in real time. When the monitored strain exceeds a preset threshold and continues for a preset time, the strain data is analyzed by the control center, and the damaged area is located based on the wavelength drift of the fiber optic grating. The electrode system, which includes a conductive coating, is activated in the located damaged area and heated by applying an electric current. The heat generated induces the shape memory alloy fibers to shrink, which are embedded in the smart aggregate; The shrinkage of the shape memory alloy fibers causes the microcapsules in the smart aggregate to rupture, releasing a repair agent that repairs the cracks.
[0024] The location of the damage region is based on the wavelength shift of the fiber grating. The wavelength shift is calculated according to the formula: ; in It is the strain coefficient. It is the temperature coefficient. It is about adapting to change. It is a temperature change; By utilizing an FBG sensor matrix, or fiber optic grating sensor matrix, millimeter-level damage localization can be achieved with an error of <±15mm. The control system activates the electrodes in the damaged area, avoiding overall heating and reducing energy consumption.
[0025] Fast response and low maintenance costs: The system can automatically identify and initiate a repair response within 10 minutes of crack initiation, containing damage in its early stages. This proactive intelligent maintenance strategy can reduce the number of major repairs and is expected to reduce the total life-cycle maintenance cost of the structure by up to 60%, making it particularly suitable for major infrastructure such as bridges and tunnels that are difficult to maintain manually infrequently.
[0026] Please see Figure 4 A construction method for self-healing concrete cracks includes the following steps: Step S1, Pre-fabrication of intelligent aggregates: After mixing the embedded microcapsules with shape memory alloy fibers, the mixture was injected into the pores of basalt aggregate and sealed with epoxy resin, and then cured at 80°C for 2 hours. Step S2, concrete pouring: The prefabricated intelligent aggregate unit is mixed into the concrete at a dosage of 3-5% of the concrete volume and then poured. During the pouring process, fiber optic grating sensor matrix is embedded in layers, with the fiber optic grating sensors arranged in a grid pattern with a longitudinal and transverse spacing of 200mm. A carbon nanotube coating or a conductive concrete coating is applied to the surface of a concrete structure as an electrode system, with the coating thickness controlled to be 1 mm. Step S3, Control System Deployment: The sensing network and the electrode system are connected to the control system, and a strain-temperature mapping model is established within the control system. ,in The activation threshold is set when the detected strain value continuously exceeds [a certain threshold]. Continue for 5 minutes.
[0027] The intelligent aggregate unit is incorporated into the concrete structure at a dosage of 3-5% of the concrete volume.
[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. An intelligent monitoring and repair system for self-healing concrete cracks, characterized in that, include: The intelligent aggregate unit is embedded in the concrete structure. The intelligent aggregate unit includes basalt aggregate and embedded microcapsules and shape memory alloy fibers encapsulated inside it. A sensing and monitoring network unit is embedded in the concrete structure to monitor the strain signal of the concrete structure in real time. The sensing and monitoring network is a fiber optic grating sensor matrix. Electrode units are placed on the surface or inside a designated area of a concrete structure to generate heat when energized. A control unit, electrically connected to the sensing and monitoring network and the electrode unit, is configured to: receive and analyze strain signals transmitted from the sensing and monitoring network, and when the strain signal exceeds a preset threshold, control the supply of power to the electrode unit in the damaged area, so as to activate the shape memory alloy fiber in the area to shrink through electrothermal effect and cause the embedded microcapsule to rupture and release the repair agent.
2. The intelligent monitoring and repair system for self-healing concrete cracks according to claim 1, characterized in that, In the intelligent aggregate unit, the basalt aggregate has a particle size of 15-25 mm; the embedded microcapsules have a particle size of 100-300 mm. m; The shape memory alloy fiber is a NiTiNol alloy fiber with a diameter of 0.2 mm.
3. The intelligent monitoring and repair system for self-healing concrete cracks according to claim 2, characterized in that, The fiber Bragg grating sensors in the sensing and monitoring network are arranged in a grid pattern with a longitudinal and transverse spacing of 200 mm, and the monitoring accuracy range is ± .
4. The intelligent monitoring and repair system for self-healing concrete cracks according to claim 3, characterized in that, The electrode system is a carbon nanotube coating or a conductive concrete coating applied to the concrete surface, wherein the resistivity of the carbon nanotube coating or the conductive concrete coating is less than [value missing]. The coating thickness of the carbon nanotube coating or conductive concrete coating is 1 mm.
5. The intelligent monitoring and repair system for self-healing concrete cracks according to claim 4, characterized in that, The control system is configured to establish a strain-temperature mapping model: ； in The activation threshold is set when the detected strain value continuously exceeds [a certain threshold]. Continue for 5 minutes.
6. The intelligent monitoring and repair system for self-healing concrete cracks according to claim 1, characterized in that, The control unit is also configured to: analyze and locate the coordinates of the area where the concrete structure is damaged based on the signals transmitted from the sensor monitoring network; Repair process initiated: Crack occurs → Fiber optic grating sensor monitors strain mutation → Control center analyzes and locates → Electrode in damaged area is activated → Electrothermal stimulation of shape memory alloy fiber shrinkage → Embedded microcapsule ruptures and releases repair agent → Dual repair completed.
7. The intelligent monitoring and repair system for self-healing concrete cracks according to claim 6, characterized in that, The location of the damage region is based on the wavelength shift of the fiber grating. The wavelength shift is calculated according to the formula: ； in It is the strain coefficient. It is the temperature coefficient. It is about adapting to change. It's a temperature change.
8. A construction method for self-healing concrete cracks, characterized in that, Includes the following steps: Step S1, Pre-fabrication of intelligent aggregates: After mixing the embedded microcapsules with shape memory alloy fibers, the mixture was injected into the pores of basalt aggregate and sealed with epoxy resin, and then cured at 80°C for 2 hours. Step S2, concrete pouring: The prefabricated intelligent aggregate unit is mixed into the concrete at a dosage of 3-5% of the concrete volume and then poured. During the pouring process, fiber optic grating sensor matrix is embedded in layers, with the fiber optic grating sensors arranged in a grid pattern with a longitudinal and transverse spacing of 200mm. A carbon nanotube coating or a conductive concrete coating is applied to the surface of a concrete structure as an electrode system, with the coating thickness controlled to be 1 mm. Step S3, Control System Deployment: The sensing network and the electrode system are connected to the control system, and a strain-temperature mapping model is established within the control system. ,in The activation threshold is set when the detected strain value continuously exceeds [a certain threshold]. Continue for 5 minutes.
9. A construction method for self-healing concrete cracks according to claim 8, characterized in that, The intelligent aggregate unit is incorporated into the concrete structure at a dosage of 3-5% of the concrete volume.