Cutting excavation construction method

Abstract

The invention discloses a cutting excavation construction method which comprises the following steps: firstly, determining an excavation boundary and a side slope contour line through measurement and calculating earth-rock volume, then arranging intercepting ditches around an excavation area to prevent surface water from flowing into the excavation area, excavating in a layered and segmented manner, trimming a side slope in time after excavation, and detecting the gradient by using a gradient ruler; and anchor rod drilling operation is conducted on the excavated side slope, steel bar anchor rods are inserted, M25 cement mortar is injected for anchoring, then a flexible protection net is hung on the anchor rods and welded and fixed, and finally a wet spraying machine is adopted for spraying C30 concrete to form the overall protection structure. According to the method, the slope stability and the construction quality are effectively improved through a systematic construction process and multiple protection measures, and the method is suitable for cutting excavation projects in infrastructure construction of roads, railways and the like.

Description

Technical Field

[0001] The present invention relates to the field of cutting excavation. More specifically, the present invention relates to a construction method for cutting excavation. Background Art

[0002] During the construction process of cutting excavation, slope stability control is one of the key issues. Traditional excavation methods usually adopt layered and segmented excavation combined with bolt support. However, in actual construction, the slope protection effect is still insufficient. On the one hand, if the slope is not supported in time after excavation, it is easily affected by rain erosion or changes in geological conditions, resulting in local collapse or landslide. On the other hand, during bolt construction, if the rock powder and debris in the drill hole are not thoroughly cleaned or the permeability of the hole wall is too high, it will affect the grouting quality, reduce the anchoring effect, and thus affect the overall stability of the slope. In addition, traditional slope protection structures (such as shotcrete) are prone to micro-cracks due to temperature stress or external loads during long-term use. After water seeps in, it may accelerate the corrosion of steel bars and the deterioration of concrete. In the prior art, the self-healing ability of concrete is limited. After the cracks expand, it is difficult to repair autonomously, affecting the durability of the structure. At the same time, under extreme temperature conditions (such as high temperature in summer or low temperature in winter), the internal temperature gradient of concrete increases, which may cause thermal stress cracks, further weakening the protection effect.

[0003] The above problems increase the safety risks and maintenance costs of cutting construction. There is an urgent need for a more reliable excavation and support method to improve slope stability, self-healing ability, and environmental adaptability. Summary of the Invention

[0004] To achieve these and other advantages according to the present invention, a preferred embodiment of the present invention provides a construction method for cutting excavation, including the following steps: S1. Determine the excavation boundary and the contour line of the excavation slope of the cutting, and calculate the earthwork volume of the cutting excavation according to the measurement data; S2. Set intercepting ditches around the cutting excavation area to intercept surface water and prevent it from flowing into the excavation area; S3. Adopt a layered and segmented excavation method for excavation, with the excavation height of each layer being 10m and the length of each segment being 20m; after each layer of excavation is completed, promptly trim the slope, and use a slope gauge to detect the slope gradient of the slope to make it meet the design requirements; S4. On the excavated slope, use a bolt drill to carry out drilling operations. The drill holes are distributed at intervals, with a hole depth of 6 - 12m. Insert steel bars into the holes as bolts, and inject M25 cement mortar for anchoring; S5. Hang a flexible protection net on the anchored bolts, and weld and fix the flexible protection net to the bolts; S6. Use a wet shotcrete machine to spray C30 concrete on the slope after installing the mesh, with a spraying thickness of 10 cm, so that the concrete, flexible protection mesh and anchor bolts form an integral protection structure.

[0005] Through layered and segmented excavation combined with slope trimming, the present invention ensures that the slope gradient meets the design requirements and improves stability. The setting of a catch water ditch effectively intercepts surface water and reduces the risk of soil erosion. The anchor bolts, flexible protection mesh and concrete form an integral protection structure, enhancing the anti-slip ability of the slope and reducing the risk of collapse. This method has high construction efficiency and remarkable protection effect, and is applicable to the cutting excavation project under complex geological conditions.

[0006] Preferably, in step S4, after the anchor bolt drilling is completed, use high-pressure air to clean the hole, remove the rock powder and debris in the hole, and then use a hole wall permeability detector to detect the permeability coefficient of the hole wall. When the permeability coefficient is greater than carry out grouting reinforcement treatment on the hole wall. The grouting material uses ultrafine cement-sodium silicate double liquid slurry, and the grouting pressure is controlled at 0.3 - 0.5 MPa to ensure the anchoring effect of the anchor bolt.

[0007] Through layered and segmented excavation combined with slope trimming, the present invention ensures that the slope gradient meets the design requirements and improves stability. The setting of a catch water ditch effectively intercepts surface water and reduces the risk of soil erosion. The anchor bolts, flexible protection mesh and concrete form an integral protection structure, enhancing the anti-slip ability of the slope and reducing the risk of collapse. This method has high construction efficiency and remarkable protection effect, and is applicable to the cutting excavation project under complex geological conditions.

[0008] Preferably, during the excavation process of step S3, distributed fiber optic sensors are implanted in the cutting slope and the surrounding soil mass. The distributed fiber optic sensors collect the strain data and displacement data of the slope soil mass in real time and transmit them wirelessly to the data processing center. Once the strain data or displacement data exceeds the preset safety threshold, the control system immediately automatically activates the alarm mechanism.

[0009] The present invention uses distributed fiber optic sensors to achieve continuous monitoring of slope strain and displacement. The data is transmitted to the control center in real time, improving the monitoring accuracy and response speed. Once the data exceeds the limit, the system automatically alarms, facilitating timely reinforcement measures to avoid slope instability accidents. This method greatly improves construction safety and is applicable to slope monitoring under high-risk geological conditions.

[0010] Preferably, in S6, a self-healing ecological protection material is added to the sprayed C30 concrete. The recommended dosage of the self-healing ecological protection material in the concrete is 1% - 3% of the concrete mass. The self-healing ecological protection material is prepared by the following process: compounding activated carbon with a porous slow-release carrier to form a composite carrier, and encapsulating urease-producing bacteria and yeast extract in the composite carrier.

[0011] In the present invention, a self - repairing ecological protection material is added to concrete. The activated carbon and the porous carrier provide a slow - release environment, and the urease - producing bacteria and yeast extract are activated at the crack, promoting mineral deposition to repair the crack. This method enhances the durability and self - repairing ability of concrete, reduces maintenance requirements, and is applicable to slope protection projects that are long - term exposed to harsh environments.

[0012] Preferably, in the self - repairing ecological protection material, the mass ratio of activated carbon, porous slow - release carrier, urease - producing bacteria, and yeast extract is controlled at (50% - 70%):(20% - 30%):(5% - 10%):(5% - 10%).

[0013] The present invention optimizes the proportion of the self - repairing material to ensure that the activated carbon and the porous carrier provide sufficient adsorption and slow - release capabilities, and the proportion of urease - producing bacteria and yeast extract is appropriate, which can not only efficiently repair cracks but also avoid waste of resources. This proportioning scheme has controllable costs and stable repair effects, and is applicable to large - scale engineering applications.

[0014] Preferably, in the S6 step, a phase - change energy - storage material is incorporated into the sprayed C30 concrete. The phase - change energy - storage material uses n - dodecane with a mass fraction of 80% - 90% as the core phase - change medium, calcium stearate with a mass fraction of 10% - 15% as the nucleating agent, and nano - graphite flakes with a mass fraction of 1% - 3% as the heat - conducting agent. It is encapsulated by urea - formaldehyde resin microcapsules to form particles with a size of 50 - 100 μm and a shell thickness of 1 - 2 μm.

[0015] The present invention adds a phase - change energy - storage material to concrete. N - dodecane absorbs and releases heat in the phase - change temperature range (28 - 32°C), effectively buffering temperature fluctuations. Calcium stearate and nano - graphite flakes improve the phase - change efficiency and thermal conductivity, and the micro - capsule encapsulation prevents leakage. This method significantly reduces the risk of temperature - stress cracks, extends the service life of the concrete structure, and is applicable to areas with large temperature differences.

[0016] Preferably, when the distributed optical fiber sensor monitors that the temperature change rate in a certain area of the concrete exceeds 1.5°C / h, or the local temperature exceeds 35°C in summer high temperature and is lower than 5°C in winter low temperature, the control system immediately sends a warning signal and locates the abnormal temperature area at the same time; when the concrete temperature rises to the phase - change temperature of 32°C of n - dodecane, the material begins to change from solid to liquid, absorbing the surrounding heat and slowing down the concrete temperature rise rate; when the temperature drops to 28°C, n - dodecane changes from liquid to solid, releasing the stored heat and preventing the concrete temperature from dropping too fast.

[0017] The present invention combines a distributed optical fiber sensor to monitor temperature changes in real - time, and the phase - change material dynamically adjusts the concrete temperature to avoid cracks caused by extreme temperature differences. The system automatically warns and locates the abnormal area, facilitating targeted treatment. This method realizes intelligent temperature control and improves the durability and safety of the concrete structure.

[0018] Preferably, during the operation of the phase change energy storage material, the distributed optical fiber sensor continuously monitors the temperature change of the concrete. The temperature data is fed back to the control system every 5 minutes. The control system calculates the phase change degree and remaining energy storage of the phase change energy storage material. If it is found that the temperature still cannot be effectively controlled, the standby phase change energy storage material supplementary device is activated to spray a protective coating containing the phase change material on the concrete surface to further enhance the temperature control ability until the concrete temperature returns to the safe range.

[0019] Through real-time data feedback and the standby supplementary device, the present invention ensures that the phase change material is always in an effective working state. When the main phase change material has insufficient energy storage, the sprayed protective coating provides additional temperature control ability to avoid temperature runaway. This method provides double guarantees and is applicable to the concrete protection project under extreme climate conditions.

[0020] The present invention has at least the following beneficial effects: The present invention provides an efficient, safe and intelligent cutting excavation construction method. By excavating in layers and sections in combination with slope trimming, bolt reinforcement, hanging a flexible protection net and spraying concrete, an overall protection structure is formed, significantly improving the slope stability and anti-slip ability; adopting high-pressure air hole cleaning and hole wall penetration detection technologies to ensure the anchoring quality, combined with distributed optical fiber sensors to monitor the slope deformation and temperature change in real time, realizing intelligent early warning and dynamic regulation; innovatively adding self-healing ecological protection materials and phase change energy storage materials to the concrete, through microbial self-healing of cracks and phase change temperature regulation of n-dodecane, effectively extending the structure life and reducing the maintenance cost; at the same time, setting a catchment ditch to prevent surface water from seeping in, combined with the standby spraying supplementary device to cope with extreme climate conditions, making this method have construction efficiency, structural durability and environmental adaptability, significantly reducing the engineering risk and maintenance cost, applicable to cutting excavation projects under various complex geological conditions, and having important popularization and application value.

[0021] Other advantages, objectives and features of the present invention will be partially reflected by the following description, and will also be understood by those skilled in the art through the research and practice of the present invention. Detailed Embodiments

[0022] The following further elaborates on the present invention in conjunction with embodiments, so that those skilled in the art can implement it with reference to the description in the specification.

[0023] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious deformations. The basic principles defined in the following description can be applied to other implementation schemes, deformation schemes, improvement schemes, equivalent schemes and other technical schemes without departing from the spirit and scope of the present invention.

[0024] It is understood that the term "a" should be construed as "at least one" or "one or more". That is, in one embodiment, the number of an element may be one, while in other embodiments, the number of the element may be multiple. The term "a" should not be construed as a limitation on the quantity.

[0025] A preferred embodiment of the present invention provides a cutting excavation construction method, comprising the following steps: S1. Determine the excavation boundary and the excavation slope contour line of the cutting, and calculate the volume of earthwork and stonework for the cutting excavation according to the measurement data; S2. Set a catch water ditch around the cutting excavation area to intercept surface water and prevent it from flowing into the excavation area; S3. Adopt a layered and segmented excavation method for excavation, with the excavation height of each layer being 10 m and the length of each segment being 20 m; after the excavation of each layer is completed, promptly trim the slope, and use a slope gauge to detect the slope of the slope to make it meet the design requirements; S4. On the slope that has been excavated and completed, use a bolt drill to carry out drilling operations. The drill holes are distributed at intervals, with the hole depth being 6 - 12 m. Insert steel bars into the holes as bolts, and inject M25 cement mortar for anchoring; S5. Hang a flexible protection net on the anchored bolts, and weld and fix the flexible protection net to the bolts; S6. Use a wet shotcreting machine to spray C30 concrete on the slope after hanging the net, with the spraying thickness being 10 cm, so that the concrete, the flexible protection net, and the bolts form an integral protection structure.

[0026] First, use a total station to carry out lofting measurement of the excavation boundary, and calculate the accurate volume of earthwork and stonework by collecting terrain data. The catch water ditch adopts a trapezoidal cross-section, with the upper opening width being 20 cm, the bottom width being 35 cm, the depth being 60 cm, and a 1% drainage slope is set at the bottom of the ditch. It is formed by on-site casting with C20 concrete.

[0027] During layered and segmented excavation, the height of each layer is controlled within 3 m (allowing an error of ±10 cm), and the length of each segment is 20 m (allowing an error of ±50 cm). The excavation is carried out by a backhoe excavator. After the excavation of each layer is completed, immediately use a slope gauge to detect the slope of the slope to ensure that it meets the design requirements. The bolt construction uses a hydraulic bolt drill, with the drill hole diameter being 42 mm, the depth being 2 m (allowing an error of ±5 cm), and the spacing being arranged in a plum blossom shape of 1.5 m × 1.5 m.

[0028] When shotcreting with a wet shotcreting machine, the nozzle is 0.8 - 1.2 m away from the slope surface, the spraying pressure is controlled at 0.4 - 0.6 MPa, and it is sprayed in layers to the designed thickness of 10 cm (allowing an error of ±5 mm). After the concrete has initially set, it is covered with geotextile for 7 days of curing. This method ensures slope stability through a standardized construction process, and the protective structure has strong integrity, and is applicable to cutting projects under surrounding rock conditions of class IV and above.

[0029] In another technical solution, in step S4, after the anchor hole drilling is completed, high-pressure air is used to clean the hole to remove rock powder and debris in the hole, and then a hole wall permeability detector is used to detect the permeability coefficient of the hole wall. When the permeability coefficient is greater than a grouting reinforcement treatment is carried out on the hole wall. The grouting material uses ultrafine cement - water glass double-fluid slurry, and the grouting pressure is controlled at 0.3 - 0.5 MPa to ensure the anchoring effect of the anchor rod.

[0030] After the drilling is completed, first use a high-pressure air pipe to blow the rock powder in the hole at a pressure of 0.6 MPa for 30 - 60 seconds until no dust is discharged from the hole mouth. Subsequently, insert the probe of the permeability detector to the bottom of the hole, inject water at a pressure of 0.1 MPa, measure the water level drop within 10 minutes, and calculate the permeability coefficient. When the measured permeability coefficient is greater than the grouting procedure is started.

[0031] The grouting material is prepared by mixing ultrafine cement (specific surface area ≥800 m² / kg) and water glass in a mass ratio of 1:0.15, and is injected using a double-fluid grouting pump at a pressure of 0.4 MPa (allowing a fluctuation of ±0.05 MPa). The grouting sequence is carried out section by section from bottom to top, with each grouting section length of 0.5 m, and the grouting speed is controlled at 5 L / min. After the grouting is completed, insert a threaded steel anchor rod, and set a rubber grout stopper at the hole mouth to prevent the slurry from overflowing.

[0032] After 24 hours of curing, a pull-out test is carried out. The pull-out resistance of a single anchor rod should be ≥50 kN. This process can effectively improve the anchoring quality, is especially applicable to fracture zones or weathered rock formations, and can increase the pull-out resistance of the anchor rod by more than 30%.

[0033] In another technical solution, during the excavation process in step S3, distributed fiber optic sensors are implanted in the cutting slope and the surrounding soil. The distributed fiber optic sensors collect the strain data and displacement data of the slope soil in real time, and transmit them wirelessly to the data processing center. Once the strain data or displacement data exceeds the preset safety threshold, the control system immediately automatically activates the alarm mechanism.

[0034] During the excavation process, a single-mode sensing optical fiber is arranged along the trend of the potential slip surface of the slope, fixed to the slope surface with U-shaped nails, with a longitudinal spacing of 1 m and a depth of 0.5 m. The optical fiber collects strain data every 5 minutes, and the measurement accuracy is ±0.01%.

[0035] The wireless transmission module uploads the data to the cloud platform in real time. The control system sets three levels of warning thresholds: yellow warning when the strain is >0.3%, orange warning when >0.5%, and red warning and triggering the sound and light alarm when >1%. Displacement monitoring uses the same optical fiber layout method, and the threshold is set to 10mm / 20mm / 30mm. The system response time is <10 seconds, which can achieve millimeter-level monitoring of slope deformation.

[0036] In another technical solution, in S6, self-repairing ecological protection materials are added to the sprayed C30 concrete, and the recommended dosage of the self-repairing ecological protection materials in the concrete is 1%-3% of the mass of the concrete. The self-repairing ecological protection materials are prepared by the following process: activated carbon is compounded with a porous slow-release carrier to form a composite carrier, and urease-producing bacteria and yeast extract are encapsulated in the composite carrier.

[0037] In the specific implementation, coal-based activated carbon with a particle size of 0.3-0.5 mm and diatomaceous earth carrier are first mixed in a mass ratio of 2:1, and heat treated at 200°C for 2 hours to form a composite carrier. Bacillus pasteurianus and yeast extract are mixed in a ratio of 1:1, and then encapsulated into the pores of the carrier by vacuum impregnation, and the encapsulation rate is controlled at 85-90%.

[0038] At the concrete mixing station, the prepared self-repairing material is added to C30 concrete at a dosage of 2% of the total amount of cementitious materials. The mixer is used for dry mixing for 60 seconds, and then mixing water is added for wet mixing for 120 seconds. During the spraying construction, the microorganisms in the material are activated by water at the cracks, decomposing urea to produce calcium carbonate precipitation, and can automatically repair micro cracks with a width of ≤0.3mm within 28 days.

[0039] Actual engineering tests show that the self-repair rate of concrete specimens mixed with this material reaches 82% at a crack width of 0.3mm, and the anti-seepage performance is improved by 2 levels. It is suitable for slope protection projects with high durability requirements.

[0040] In another technical solution, in the S6 step, a phase change energy storage material is added to the sprayed C30 concrete. The phase change energy storage material has 80% to 90% by mass of n-dodecane as a core phase change medium, 10% to 15% by mass of calcium stearate as a nucleating agent, and 1% to 3% by mass of nano-graphite flakes as a thermal conductor. The phase change energy storage material is encapsulated by urea-formaldehyde resin microcapsules to form particles of 50 to 100 μm and a shell thickness of 1 to 2 μm.

[0041] During implementation, 85% of n-dodecane with a purity of ≥98%, 12% of calcium stearate, and 3% of nanographite flakes are mixed and heated to 50°C to melt. Urea-formaldehyde resin prepolymer is added at a stirring speed of 2000r / min by in-situ polymerization to form microcapsules with a particle size of 80±20μm. During the concrete mixing stage, phase change microcapsules are added at a dosage of 3% of the total amount of cementitious materials. The extended mixing time method is adopted, first dry mixing with aggregate for 90 seconds, and then wet mixing for 150 seconds. In the formed concrete specimens, the microcapsules are evenly distributed, and the shell integrity is ≥95%. Test data show that the internal temperature difference of concrete mixed with this material is reduced by 4-6°C at 35°C, and the temperature stress is reduced by more than 30%, effectively preventing the occurrence of temperature cracks.

[0042] In another technical solution, when the distributed optical fiber sensor detects that the temperature change rate of a certain area of concrete exceeds 1.5℃ / h, or the local temperature exceeds 35℃ in high summer and is lower than 5℃ in low winter, the control system immediately sends a warning signal and locates the abnormal temperature area at the same time; when the concrete temperature rises to reach the phase change temperature of 32℃ of n-dodecane, the material begins to change from solid to liquid, absorbing the surrounding heat and slowing down the rate of increase in concrete temperature; when the temperature drops to 28℃, n-dodecane changes from liquid to solid, releasing the stored heat and preventing the concrete temperature from dropping too quickly.

[0043] This claim specifies the temperature monitoring and phase change control system. During implementation, an optical fiber temperature measurement point is arranged every 5m² along the concrete surface, and a distributed temperature measurement system is used for real-time monitoring, with a temperature resolution of 0.1°C and a sampling interval of 5 minutes. The control system is set as follows: a first-level alarm when the temperature is >35°C or <5°C, and a second-level alarm when the rate of change is >1.5°C / h. The phase change material begins to melt and absorb heat at 32°C, and the measured latent heat of phase change reaches 180-200kJ / kg. When local overtemperature is detected, the system automatically marks the abnormal area and activates the sound and light alarm. At the same time, the temperature curve of each measuring point is displayed in real time through the LED display.

[0044] In another technical solution, while the phase change energy storage material is taking effect, the distributed optical fiber sensor continuously monitors the temperature change of the concrete and feeds back the temperature data to the control system every 5 minutes. The control system calculates the phase change degree and remaining energy storage of the phase change energy storage material. If it is found that the temperature is still not effectively controlled, the standby phase change energy storage material replenishing device is started to spray a protective coating containing phase change material onto the concrete surface to further enhance the temperature control capability until the concrete temperature returns to a safe range.

[0045] This claim is aimed at the implementation of the backup temperature control system. An industrial computer is set up in the control room to update the temperature data of each measuring point every 5 minutes and calculate the residual phase change capacity of the phase change material in real time. When the phase change degree of a certain area is greater than 80% and there is still overtemperature, the system automatically starts the spraying robot.

[0046] The spraying system uses airless spraying. The spray gun is 30 - 50 cm away from the slope surface, and a protective coating containing 10% phase change microcapsules is sprayed. The coating thickness is 0.3 - 0.5 mm. A protective film is formed 2 hours after spraying, which can provide an additional 30% temperature control ability. Practical applications show that this backup system can further reduce the concrete temperature fluctuation under extreme weather by 2 - 3 °C, ensuring the long-term durability of the protective structure.

[0047] Although the embodiments of the present invention have been disclosed as above, it is not limited to the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to the specific details and the embodiments shown and described here.

Claims

1. A cutting excavation construction method, characterized in that, It includes the following steps: S1. Determine the excavation boundary and the contour line of the cutting slope, and calculate the volume of earthwork for the cutting excavation based on the measurement data; S2. Set up intercepting ditches around the cutting excavation area to intercept surface water and prevent it from flowing into the excavation area; S3. Carry out the excavation in a layered and segmented manner. The excavation height for each layer is 10 m, and the length for each segment is 20 m. After each layer of excavation is completed, promptly trim the slope, and use a slope gauge to detect the slope gradient to make it meet the design requirements; S4. On the slope that has been excavated, use a rock bolt drilling rig to carry out drilling operations. The drill holes are distributed at intervals, with a hole depth of 6 - 12 m. Insert steel bars into the holes as rock bolts, and inject M25 cement mortar for anchoring; S5. Hang a flexible protective net on the anchored rock bolts, and weld and fix the flexible protective net to the rock bolts; S6. Use a wet shotcreting machine to spray C30 concrete on the slope after hanging the net. The spraying thickness is 10 cm, so that the concrete, the flexible protective net, and the rock bolts form an integral protective structure.

2. The cutting excavation construction method according to claim 1, characterized in that In step S4, after the anchor rod drilling is completed, high-pressure air is used to clean the hole to remove rock powder and debris in the hole. Then, a hole wall permeability detector is used to detect the permeability coefficient of the hole wall. When the permeability coefficient is greater than , grouting reinforcement treatment is carried out on the hole wall. The grouting material uses ultra-fine cement-sodium silicate double-fluid slurry, and the grouting pressure is controlled at 0.3-0.5 MPa to ensure the anchoring effect of the anchor rod.

3. The cutting excavation construction method according to claim 1, characterized in that During the excavation process in step S3, distributed fiber optic sensors are implanted in the cutting slope and the surrounding soil mass. The distributed fiber optic sensors collect the strain data and displacement data of the slope soil mass in real time, and transmit them wirelessly to the data processing center. Once the strain data or displacement data exceeds the preset safety threshold, the control system immediately automatically activates the alarm mechanism.

4. The cutting excavation construction method according to claim 3, characterized in that, In S6, a self - repairing ecological protection material is added to the sprayed C30 concrete. The recommended dosage of the self - repairing ecological protection material in the concrete is 1% - 3% of the concrete mass. The self - repairing ecological protection material is prepared through the following process: Activated carbon is compounded with a porous slow - release carrier to form a composite carrier, and urease - producing bacteria and yeast extract are encapsulated in the composite carrier.

5. The cutting excavation construction method according to claim 4, characterized in that In the self - repairing ecological protection material, the mass ratio of activated carbon, porous slow - release carrier, urease - producing bacteria, and yeast extract is controlled at (50% - 70%):(20% - 30%):(5% - 10%):(5% - 10%).

6. The cutting excavation construction method according to claim 5, characterized in that, In step S6, a phase - change energy - storage material is incorporated into the sprayed C30 concrete. The phase - change energy - storage material uses n - dodecane with a mass fraction of 80% - 90% as the core phase - change medium, calcium stearate with a mass fraction of 10% - 15% as the nucleating agent, and nano - graphite flakes with a mass fraction of 1% - 3% as the heat - conducting agent. It is encapsulated by urea - formaldehyde resin microcapsules to form particles with a size of 50 - 100 μm and a shell thickness of 1 - 2 μm.

7. The cutting excavation construction method according to claim 6, characterized in that, When the distributed fiber optic sensors monitor that the temperature change rate in a certain area of the concrete exceeds 1.5℃ / h, or the local temperature exceeds 35℃ in summer high temperature and is lower than 5℃ in winter low temperature, the control system immediately sends a warning signal and locates the abnormal temperature area at the same time; When the concrete temperature rises to the phase - change temperature of 32℃ of n - dodecane, the material begins to change from solid to liquid, absorbing the surrounding heat and slowing down the rate of increase in the concrete temperature; When the temperature drops to 28℃, n - dodecane changes from liquid to solid, releasing the stored heat and preventing the concrete temperature from dropping too fast.

8. The cutting excavation construction method according to claim 7, characterized in that, During the process of the phase change energy storage material playing its role, the distributed optical fiber sensor continuously monitors the temperature change of the concrete. The temperature data is fed back to the control system every 5 minutes. The control system calculates the phase change degree and remaining energy storage of the phase change energy storage material. If it is found that the temperature still cannot be effectively controlled, the standby phase change energy storage material supplementary device is started to spray a protective coating containing the phase change material on the concrete surface to further enhance the temperature control ability until the concrete temperature returns to the safe range.