River bank slope protection for cofferdam construction and construction method thereof

Abstract

The invention relates to the technical field of river bank protection, in particular to a river bank slope protection for cofferdam construction and a construction method thereof. S2, construction of a near-water area structure; s3, construction of a far water area structure; s4, ecological enhancement; triple optimization of river bank protection is achieved through dynamic water level monitoring and modular design, a double-layer reinforced concrete and elastic sealant structure is adopted in a near-water area, the compressive strength is improved by 20%, the crack width is smaller than or equal to 0.2 mm, and material waste is reduced by 15% in cooperation with dynamic width adjustment (+ / -2 m); the mold bag concrete slope protection is combined with an atomization spraying system, the anti-scouring capacity reaches 5 m / (m.s), the vegetation coverage rate is larger than or equal to 80% within 3 months, and the water and soil loss rate is reduced by 70%; the modular honeycomb structure inflation assembly efficiency is improved by 40%, the transportation cost is reduced by 50%, the distributed sensors achieve structure displacement / pressure three-level early warning, the operation and maintenance cost is reduced by 70%, the overall service life is prolonged by more than 5 years, and an ecological-engineering collaborative protection system is formed.

Description

Technical Field

[0001] The present invention relates to the technical field of river bank protection, in particular to a river bank slope protection for cofferdam construction and a construction method thereof. Background Art

[0002] With global climate change and intensified human activities, riverbank erosion, soil erosion and other problems are becoming increasingly serious, and traditional riverbank protection technologies face multiple challenges. Existing technologies, while rigid structures have a certain ability to resist scour, suffer from significant ecological damage, incompatibility between material stiffness and the natural environment, and difficulty adapting to dynamic hydrological conditions. Hard slope protection cuts off vegetation roots, leading to loss of biodiversity on the slopes and a soil erosion rate exceeding 30%. Furthermore, fixed structures are prone to stress concentration when water levels fluctuate between dry and wet seasons, causing structural damage such as cracking and spalling, resulting in high maintenance costs. Modular assembly technology and ecological slope protection concepts are gradually being applied to riverbank projects, but significant limitations remain. Existing inflatable modules are mostly made of ordinary PVC, which lacks airtightness and results in a leakage rate exceeding 15% during long-term use. Furthermore, they lack intelligent monitoring methods, preventing real-time feedback on structural stability. Ecological protection layers often struggle to withstand initial water erosion due to low grass germination rates and weak root soil-fixing capabilities. Furthermore, existing technologies are poorly adaptable to dynamic changes in water levels. The structural width near the water is fixed, and during the dry season, 20% to 30% of the protection area is ineffective, resulting in material waste. The slope design far from the water fails to consider foundation settlement compensation, resulting in frequent cases of settlement deformation exceeding 5% within three years. In terms of construction efficiency and intelligent monitoring, traditional processes rely on manual vibration and layered pouring, with an effective construction area of ​​less than 20m² per day. In addition, the concrete density fluctuates greatly, easily forming a honeycombed surface. The monitoring system mostly uses discrete sensors, with data sampling intervals of more than 1 hour, and cannot warn of sudden structural instability. Summary of the Invention

[0003] To this end, the present invention provides a river bank slope protection for cofferdam construction and a construction method thereof to solve the above-mentioned problems.

[0004] The present invention provides the following technical solution: a river bank slope protection method for cofferdam construction, comprising the following steps: S1, regional adaptability division; S2, construction of structures near the water; S3, far water area structure construction; S4, ecological enhancement.

[0005] As a preferred solution of the present invention, in S1, more specifically: The slope protection area is divided into the near-water area and the far-water area. The near-water area adopts a double-layer reinforced concrete structure, while the far-water area adopts bagged concrete protection. The width of the near-water area is dynamically adjusted according to the water level of the river during the dry season, with an adjustment range of ±2m; The slope angle of the far water area is ≤30°, and a 2m wide transition zone is set at the junction with the existing riverbed.

[0006] As a preferred solution of the present invention, in S2, it further includes: S2-1, double-layer reinforced concrete paving: A 30cm thick C30 reinforced concrete paving layer is laid between railway piers, with a 20cm crushed stone cushion layer underneath. The steel mesh is 100×100mm in a bidirectional arrangement, with a Φ12mm steel mesh specification. 500mm thick reinforcement bars of Φ8mm are installed between the double-layer steel mesh. The concrete slump is controlled at 180±20mm. The paving layer is poured in sections, with a single section length of ≤20m. S2-2, pier skirt protection: 15cm thick C30 reinforced concrete is used for paving between piers, with skirts installed at both ends. The skirts are made of cast-in-place C30 concrete, with a width of ≥1.2m and a height of ≥2.5m from the bottom of the skirt to the riverbed. A 2cm thick elastic sealant with a tensile strength of ≥5MPa is installed between the skirt and the main paving layer; S2-3, clearance control: the clearance between the paved top surface and the bridge is ≥7.6m, the clearance error is ≤±10mm, and a laser rangefinder is used for real-time calibration.

[0007] As a preferred solution of the present invention, in S3-S4, more specifically: Use 15cm thick C20 bagged concrete for slope protection, and set 1m wide maintenance steps every 20m. The compressive strength of the bagged concrete should be ≥15MPa, and the permeability coefficient should be ≤1×10⁻³cm / s. The maintenance steps should use C25 cast-in-place concrete, with a step height of 15cm and a width of 30cm. Φ16mm anti-slip strips should be installed between the steps. A polypropylene grid vegetation mat is composited on the surface of the protective layer, with tall fescue seeds pre-installed in the grid. The humidity is maintained at ≥60% in conjunction with the atomizing spray system to achieve ecological restoration during the construction period. The polypropylene grid aperture is ≤5mm, the unit area mass is ≥300g / m², the anti-ultraviolet aging life is ≥5 years, the grass seed sowing amount is 150g / m², the covering soil thickness is ≤1cm, the atomized particle diameter of the spray system is ≤50μm, the single nozzle coverage radius is ≥3m, and the working pressure is 0.2-0.4MPa.

[0008] A river bank slope protection construction method for cofferdam construction includes the following steps: S1, terrain preprocessing; S2, modular assembly near the water; S3, inflation module assembly; S4, module inflation and curing; S5, integrated laying of protective layer; S6, polypropylene grid laying; S7, gravel bag laying; S8, simultaneous implementation of ecological restoration; S9, grass seed sowing; S10, spray curing; S11, dynamic monitoring and adjustment; S12, pressure monitoring; S13, displacement monitoring; S14, abnormal warning.

[0009] As a preferred solution of the present invention, in S1-S14, more specifically: In S1, mechanical and manual clearing is used, leaving a 2-3 cm undisturbed soil layer. The clearing depth error is ≤±5 mm. Crawler excavators are used for mechanical clearing, and wooden tamping is used for manual finishing. Rubber protective covers are installed within 2 m around the piers. The thickness of the protective covers is ≥5 mm and the impact strength is ≥20 kJ / m². Said S2 includes S3-S4. In S3-S4, an inflatable honeycomb module is spliced ​​together by NdFeB magnetic locks and nylon straps to form a 2m×1m×0.8m honeycomb structure. The contact surface of the magnetic lock is sandblasted to a roughness Ra ≤ 0.8μm. The contact portion between the nylon strap and the module is provided with an anti-slip buckle with a locking torque ≥ 15N·m. The module is inflated to 0.08MPa through a quick-insert valve and allowed to stand for 24 hours to allow the PVC mesh fabric to set. The inflation process is monitored in real time by a pressure sensor. When the pressure in any air chamber is less than 0.04MPa, air is automatically replenished at a replenishment rate ≤ 0.5MPa / min. The power of the inflation equipment is ≥ 3kW. Said S5 includes S6-S7. In S6-S7, the outer surface of the module is covered with a polypropylene mesh with a pore size of ≤5mm, the mesh is coated with a wear-resistant coating, and the wear rate is ≤5% / 1000h. The mesh and the module are bonded with hot melt adhesive with a bonding strength of ≥2MPa. 30cm thick gravel bags are laid, and the gravel bags are sewn with polyester thread with a wire diameter of ≥2mm. The gravel bags and the mesh are laid alternately with an interval of ≤20cm and a staggered seam of ≥30cm. The gravel bags are made of polypropylene woven cloth with a tensile strength of ≥150kN / m. Said S8 includes S9-S10, in which tall fescue seeds are sown with a soil covering thickness of ≤1 cm, a pneumatic seeder is used for sowing, a sowing uniformity of ≥90%, a sowing speed of ≤0.5 m / s, an atomizing spray system is used to maintain soil moisture ≥60%, a spraying cycle of 8:00-18:00 daily, a HDPE pipe is used for the spray pipe, a nominal pressure of ≥1.0 MPa, and a nozzle atomization angle of ≥120°; The S11 includes S12-S14. In S12-S14, distributed pressure sensors are deployed to monitor the air chamber pressure in real time. The sensor accuracy is ±0.5%, the waterproof grade is IP68, the operating temperature is -20℃~80℃, and the GNSS module is used to monitor the module plane displacement and settlement. The positioning accuracy is ≤2cm. The monitoring data is uploaded to the central control unit through the LoRa protocol. The transmission distance is ≥1km. The central control unit sets three levels of warning thresholds: the first level is a single air chamber pressure of <0.03MPa for >10min, the second level is the maximum displacement of the module >5mm / 24h, and the third level is the ambient temperature >60℃ or the humidity >95%. After the warning is triggered, the sound and light alarm is automatically activated, and a text message is sent to notify the operation and maintenance personnel.

[0010] As a preferred solution of the present invention, the distributed sensor includes a pressure sensor, a displacement monitor, and an environmental perception unit. The pressure sensor has a range of 0-1.5 MPa and an accuracy of ±0.5% FS. The displacement monitor has a positioning accuracy of ≤2 cm and a data update frequency of ≥1 Hz. The central control unit is equipped with an ARM Cortex-A53 processor, runs an embedded Linux system, supports Modbus / RTU protocol, has a built-in 4G / 5G communication module, and a data upload cycle of ≤5 minutes. The central control unit is equipped with a UPS backup power supply with a power outage life of ≥72 hours. The early warning trigger establishes a prediction model based on fuzzy logic and neural network, and the early warning response time is ≤1s. The early warning trigger supports customized early warning thresholds and can distinguish between normal operating condition fluctuations and abnormal operating conditions.

[0011] Compared with the prior art, the present invention has the following beneficial effects: In the present invention, triple optimization of riverbank protection is achieved through dynamic water level monitoring and modular design: a double-layer reinforced concrete + elastic sealant structure is adopted in the near-water area, with the compressive strength increased by 20%, the crack width ≤0.2mm, and the dynamic width adjustment (±2m) reduces material waste by 15%; the mold bag concrete slope protection is combined with an atomizing spray system, with an anti-scouring capacity of 5m³ / (m²·s), a vegetation coverage rate ≥80% for 3 months, and a soil erosion rate reduced by 70%; the modular honeycomb structure inflation assembly efficiency is increased by 40%, and the transportation cost is reduced by 50%. Distributed sensors realize three-level early warning of structural displacement / pressure, reducing operation and maintenance costs by 70%, and extending the overall service life by more than 5 years, forming an ecological-engineering collaborative protection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a flow chart of the river bank slope protection method of the present invention; Figure 2 This is a flow chart of the river bank slope protection construction method of the present invention. DETAILED DESCRIPTION

[0013] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0014] See also Figure 1-Figure 2 The technical solution provided by the present invention specifically includes the following embodiments: Embodiment: A river bank slope protection method for cofferdam construction comprises the following steps: S1, regional adaptability division; S2, construction of structures near the water; S3, far water area structure construction; S4, ecological enhancement; Through drone mapping and GIS data analysis, the riverbank is divided into a near-water zone (dynamically adjusted width) and a far-water zone (slope ≤ 30°). Water level sensors are installed at the border of the near-water zone to monitor water level changes in real time during the dry season and dynamically adjust the width (±2m). Double-layer reinforced concrete paving: A 30cm thick C30 concrete layer was laid, with a 12mm Φ threaded steel mesh arranged bidirectionally (spacing 100×100mm), and 8mm Φ reinforcement bars spaced 500mm apart. The paving was cast in sections over a length of 18m, and after pouring, the paving was covered with geotextiles and cured for 7 days. Pier skirt protection: The skirt is cast in place with C30 concrete, with a width of 1.5m and the bottom embedded in the riverbed 2.8m. Elastic sealant (tensile strength 5.2MPa) is filled between the skirt and the main structure.

[0015] The bagged concrete slope protection uses 15cm thick C20 concrete, with a 4mm pore size and a compressive strength of 18MPa. Inspection steps are set up every 20m, cast with C25 concrete, and covered with anti-slip strips (Φ16mm stainless steel). A polypropylene mesh mat (pore size 3mm, unit mass 350g / m²) was laid, tall fescue seeds were sown at 150g / m², and water was sprayed for 6 hours daily using a misting spray system (humidity 65%). Dynamically adjust the width of the near-water zone to adapt to water level changes and reduce structural stress concentration. The double-layer reinforced concrete and crushed stone cushion are combined, and the steel mesh restrains concrete deformation to enhance scour resistance. The bagged concrete drains through the mesh pores to adapt to slight foundation settlement. Dynamic width adjustment reduces construction waste and saves 15% of material costs. Elastic sealant reduces the risk of structural cracking and extends the service life by more than 5 years. Vegetation cover reduces slope erosion and reduces soil and water loss rate by 70%.

[0016] In S1, more specifically: The slope protection area is divided into the near-water area and the far-water area. The near-water area adopts a double-layer reinforced concrete structure, while the far-water area adopts bagged concrete protection. The width of the near-water area is dynamically adjusted according to the water level of the river during the dry season, with an adjustment range of ±2m; The slope angle of the far water area is ≤30°, and a 2m wide transition zone is set at the junction with the existing riverbed; Φ12mm steel bars are welded into a bidirectional grid with a spacing of 100mm. Φ8mm reinforcement bars are arranged vertically and crosswise. The concrete slump is controlled at 170mm (error ±10mm). A Leica total station is used to monitor the elevation of the top surface of the paving layer in real time, with an error of ≤±5mm. Bidirectional reinforcement and reinforcing bars form a composite load-bearing structure to resist water impact loads. High-flow concrete (180mm) ensures density and reduces honeycomb surface defects. Through the above method, the double-layer steel mesh increases the compressive strength by 20%, the crack width is ≤0.2mm, and the laser calibration makes the clearance error ≤±3mm, meeting the bridge clearance requirements.

[0017] In S2, it also includes: S2-1, double-layer reinforced concrete paving: A 30cm thick C30 reinforced concrete paving layer is laid between railway piers, with a 20cm crushed stone cushion layer underneath. The steel mesh is 100×100mm in a bidirectional arrangement, with a Φ12mm steel mesh specification. 500mm thick reinforcement bars of Φ8mm are installed between the double-layer steel mesh. The concrete slump is controlled at 180±20mm. The paving layer is poured in sections, with a single section length of ≤20m. S2-2, pier skirt protection: 15cm thick C30 reinforced concrete is used for paving between piers, with skirts installed at both ends. The skirts are made of cast-in-place C30 concrete, with a width of ≥1.2m and a height of ≥2.5m from the bottom of the skirt to the riverbed. A 2cm thick elastic sealant with a tensile strength of ≥5MPa is installed between the skirt and the main paving layer; S2-3, clearance control: the clearance between the paved top surface and the bridge is ≥7.6m, the clearance error is ≤±10mm, and a laser rangefinder is used for real-time calibration; The mold bag is made of polypropylene woven cloth (tensile strength 200kN / m), with an inflation pressure of 0.1MPa. Concrete is pumped into the mold bag with a thickness error of ≤±2cm. 10 atomizing nozzles (covering radius 3m) are installed, with nozzles atomizing particles of 50μm. The water spraying time is 8:00-18:00 every day. The mold bag restricts the flow of concrete, forming a uniform thickness slope protection with a low permeability coefficient (1×10⁻³cm / s). The polypropylene grid fixes the grass seeds, and the spray system maintains the humidity for seed germination (≥60%). Through the above method, the anti-scouring ability of the bagged concrete reaches 5m³ / (m²·s), which is three times higher than that of traditional mortar masonry. The grass seed germination rate is ≥95%, and the vegetation coverage rate within 3 months is ≥80%.

[0018] In S3-S4, more specific is: Use 15cm thick C20 bagged concrete for slope protection, and set 1m wide maintenance steps every 20m. The compressive strength of the bagged concrete should be ≥15MPa, and the permeability coefficient should be ≤1×10⁻³cm / s. The maintenance steps should use C25 cast-in-place concrete, with a step height of 15cm and a width of 30cm. Φ16mm anti-slip strips should be installed between the steps. A polypropylene grid vegetation mat is composited on the surface of the protective layer, with tall fescue seeds pre-installed in the grid. The humidity is maintained at ≥60% in conjunction with the atomizing spray system to achieve ecological restoration during the construction period. The polypropylene grid aperture is ≤5mm, the unit area mass is ≥300g / m², the anti-ultraviolet aging life is ≥5 years, the grass seed sowing amount is 150g / m², the covering soil thickness is ≤1cm, the atomized particle diameter of the spray system is ≤50μm, the single nozzle coverage radius is ≥3m, and the working pressure is 0.2-0.4MPa.

[0019] A river bank slope protection construction method for cofferdam construction includes the following steps: S1, terrain preprocessing; S2, modular assembly near the water; S3, inflation module assembly; S4, module inflation and curing; S5, integrated laying of protective layer; S6, polypropylene grid laying; S7, gravel bag laying; S8, simultaneous implementation of ecological restoration; S9, grass seed sowing; S10, spray curing; S11, dynamic monitoring and adjustment; S12, pressure monitoring; S13, displacement monitoring; S14, abnormal warning.

[0020] The 2m×1m inflatable modules were spliced ​​using NdFeB magnetic locks (contact surface Ra 0.6μm). The nylon straps had a locking torque of 18N·m, an inflation pressure of 0.08MPa, and were left to set for 24 hours. The modules were covered with a polypropylene mesh (pore size 2mm) with a hot melt adhesive strength of 2.5MPa. The gravel bags were sewn with polyester thread (diameter 2.5mm). The honeycomb structure is quickly assembled through airtight splicing and forms a stable support system after inflation. Distributed pressure sensors (accuracy ±0.5%) provide real-time feedback on the air chamber pressure and automatically replenish air to maintain structural stability. Through the above method, modular assembly shortens the construction period by 40%, the daily laying volume of a single person reaches 50m², the weight of the module is reduced by 60% compared with the concrete structure, and the transportation cost is reduced by 50%.

[0021] In S1-S14, more specifically: In S1, mechanical and manual clearing is used, leaving a 2-3 cm undisturbed soil layer. The clearing depth error is ≤±5 mm. Crawler excavators are used for mechanical clearing, and wooden tamping is used for manual finishing. Rubber protective covers are installed within 2 m around the piers. The thickness of the protective covers is ≥5 mm and the impact strength is ≥20 kJ / m². S2 includes S3-S4. In S3-S4, inflatable honeycomb modules are spliced ​​together using NdFeB magnetic locks and nylon straps to form a 2m×1m×0.8m honeycomb structure. The contact surface of the magnetic locks is sandblasted to a roughness of Ra ≤ 0.8μm. Anti-slip buckles are installed at the contact points between the nylon straps and the modules, with a locking torque ≥ 15N·m. The modules are inflated to 0.08MPa through a quick-insert valve and allowed to stand for 24 hours to allow the PVC mesh to set. The inflation process is monitored in real time by a pressure sensor. When the pressure in any air chamber is less than 0.04MPa, air is automatically replenished at a rate ≤ 0.5MPa / min. The inflation equipment power is ≥ 3kW. S5 includes S6-S7. In S6-S7, the outer surface of the module is covered with a polypropylene mesh with a pore size of ≤5mm. The mesh is coated with a wear-resistant coating with a wear rate of ≤5% / 1000h. The mesh and the module are bonded with hot melt adhesive with a bonding strength of ≥2MPa. 30cm thick gravel bags are laid. The gravel bags are sewn with polyester thread with a wire diameter of ≥2mm. The gravel bags and the mesh are laid alternately with a spacing of ≤20cm and a staggered seam of ≥30cm. The gravel bags are made of polypropylene woven cloth with a tensile strength of ≥150kN / m. S8 includes S9-S10. In S9-S10, tall fescue seeds are sown with a soil covering thickness of ≤1 cm. A pneumatic seeder is used for sowing with a sowing uniformity of ≥90% and a sowing speed of ≤0.5 m / s. A mist spraying system is used to maintain soil moisture ≥60%. The spraying cycle is from 8:00 to 18:00 daily. The spraying pipes are made of HDPE pipes with a nominal pressure of ≥1.0 MPa and a nozzle atomization angle of ≥120°. S11 includes S12-S14. Distributed pressure sensors are deployed in S12-S14 to monitor the air chamber pressure in real time. The sensor has an accuracy of ±0.5%, a waterproof rating of IP68, and an operating temperature of -20°C to 80°C. A GNSS module is used to monitor the module's plane displacement and settlement, with a positioning accuracy of ≤2cm. The monitoring data is uploaded to the central control unit via the LoRa protocol, with a transmission distance of ≥1km. The central control unit sets three levels of warning thresholds: the first level is a single air chamber pressure of <0.03MPa for >10min, the second level is the maximum module displacement of >5mm / 24h, and the third level is the ambient temperature >60°C or the humidity >95%. Once the warning is triggered, an audible and visual alarm is automatically activated, and a text message is sent to notify the operation and maintenance personnel. One pressure sensor (range 0-1.5MPa) is placed every 50m². The GNSS module monitors module displacement (accuracy 1.5cm). The central control unit (ARM Cortex-A53) receives the data and triggers a three-level warning (such as an audible and visual alarm when the pressure is less than 0.03MPa). Combine historical data with real-time monitoring values ​​to dynamically determine abnormal operating conditions (e.g., temperature > 60°C triggers a third-level warning). The data transmission cycle is 5 minutes, and the UPS can last 72 hours after a power outage. Through the above method, the risk of structural instability can be warned one hour in advance, the accident rate can be reduced by 90%, remote monitoring can replace manual inspections, and operation and maintenance costs can be reduced by 70%.

[0022] Distributed sensors include pressure sensors, displacement monitors, and environmental sensing units. The pressure sensor has a range of 0-1.5MPa and an accuracy of ±0.5%FS. The displacement monitor has a positioning accuracy of ≤2cm and a data update frequency of ≥1Hz. The central control unit is equipped with an ARM Cortex-A53 processor, runs an embedded Linux system, supports Modbus / RTU protocols, and has a built-in 4G / 5G communication module. The data upload cycle is ≤5min and the central control unit is equipped with a UPS backup power supply with a power outage life of ≥72 hours. The early warning trigger establishes a prediction model based on fuzzy logic and neural networks. The early warning response time is ≤1s. The early warning trigger supports custom early warning thresholds and can distinguish between normal operating fluctuations and abnormal operating conditions.

[0023] In this invention, through drone mapping and GIS data analysis, the river bank is divided into a near-water area (width dynamically adjusted) and a far-water area (slope ≤ 30°). A water level sensor is installed at the boundary of the near-water area to monitor the water level changes in the dry season in real time and dynamically adjust the width (±2m). Double-layer reinforced concrete paving is carried out: a 30cm thick C30 concrete layer is laid, and the steel mesh adopts Φ12mm threaded steel arranged in two directions (spacing 100×100mm), and the reinforcing bars Φ8mm are spaced 500mm apart. The pier will be cast in sections for a length of 18m. After pouring, the pier will be covered with geotextile and cured for 7 days. For pier skirt protection, the skirt will be cast in-situ with C30 concrete, 1.5m wide, and embedded 2.8m into the riverbed. Elastic sealant (tensile strength 5.2MPa) will be filled between the skirt and the main structure. The bagged concrete slope protection will be made of 15cm thick C20 concrete with a 4mm pore size and 18MPa compressive strength. Maintenance steps will be provided every 20m, cast with C25 concrete. The surface will be paved with anti-slip strips (Φ16mm stainless steel) and polypropylene mesh vegetation mats (3mm pore size, unit mass 350g / m²). Tall fescue seeds will be sown at a rate of 150g / m². A misting spray system will spray water for 6 hours daily (humidity 65%). Dynamic adjustment of the width of the near-water zone will adapt to water level changes and reduce structural stress concentration. A double-layer reinforced concrete layer is combined with a crushed stone cushion. The steel mesh constrains concrete deformation, enhancing scour resistance. The bagged concrete drains through the mesh pores. , adapting to slight foundation settlement, dynamically adjusting width reduces construction waste and saves 15% in material costs. Elastic sealant reduces the risk of structural cracking and extends its service life by more than 5 years. Vegetation cover reduces slope erosion and reduces soil and water loss by 70%. Φ12mm steel bars are welded into a bidirectional grid with a spacing of 100mm. Φ8mm reinforcement bars are arranged vertically and crosswise. Concrete slump is controlled at 170mm (error ±10mm). A Leica total station is used to monitor the elevation of the paving layer in real time, with an error of ≤±5mm. The bidirectional reinforcement and reinforcement form a composite load-bearing structure to resist water impact loads. High-flow concrete (180mm) ensures density and reduces honeycomb surface defects. Through the above method, the double-layer steel mesh increases compressive strength by 20%, crack width ≤0.2mm, and laser calibration reduces clearance error to ≤±3mm, meeting bridge clearance requirements. The mold bag is made of polypropylene woven cloth (tensile strength 200kN / m) and the inflation pressure is 0.1MPa, concrete is pumped into the mold bag, with a thickness error of ≤±2cm, 10 atomizing nozzles are installed (covering radius 3m), the nozzle atomizing particles are 50μm, and the water spraying time is 8:00-18:00 every day. The mold bag restricts the flow of concrete to form a uniform thickness slope protection with a low permeability coefficient (1×10⁻³cm / s). The polypropylene grid fixes the grass seeds, and the spraying system maintains the seed germination humidity (≥60%). Through the above method, the mold bag concrete has an anti-scouring ability of 5m³ / (m²·s), which is 3 times higher than that of traditional mortar masonry. The grass seed germination rate is ≥95%, and the vegetation coverage rate is ≥80% within 3 months. Neodymium iron boron magnetic lock (contact surface Ra 0.6μm) splicing 2m×1m inflatable modules, nylon strap locking torque 18N·m, inflation pressure 0.08MPa, standing for 24 hours to set, covered with polypropylene mesh (pore size 2mm), hot melt adhesive bonding strength 2.5MPa, gravel bags sewn with polyester thread (wire diameter 2.5mm), honeycomb structure through airtight splicing to achieve rapid assembly, after inflation to form a stable support system, distributed pressure sensor (accuracy ±0.5%) real-time feedback air chamber pressure, automatic air replenishment to maintain structural stability, through the above method, modular assembly shortens the construction period by 40%, a single person daily laying volume of 50m², module weight is reduced by 60% compared with concrete structure, transportation cost is reduced by 50%, one pressure sensor (range 0-1.5MPa) is arranged every 50m², GNSS module monitors module displacement (accuracy 1.5cm), central control unit (ARM The Cortex-A53 receives data, triggering a third-level warning (such as an audible and visual alarm when the pressure drops below 0.03 MPa). It then combines historical data with real-time monitoring values ​​to dynamically identify abnormal operating conditions (such as a temperature exceeding 60°C triggering a third-level warning). The data transmission cycle is 5 minutes, and the UPS can last 72 hours after a power outage. This method can provide an early warning of structural instability risks one hour in advance, reducing the accident rate by 90%. Remote monitoring replaces manual inspections, reducing operation and maintenance costs by 70%. The present invention achieves triple optimization of riverbank protection through dynamic water level monitoring and modular design: the near-water area adopts a double-layer reinforced concrete + elastic sealant structure, which increases the compressive strength by 20%, reduces the crack width by 0.2mm, and combines with dynamic width adjustment (±2m) to reduce material waste by 15%; the mold bag concrete slope protection is combined with an atomizing spray system, with an anti-scouring capacity of 5m³ / (m²·s), a vegetation coverage rate of ≥80% for 3 months, and a soil erosion rate reduced by 70%; the modular honeycomb structure inflation assembly efficiency is increased by 40%, and transportation costs are reduced by 50%. Distributed sensors realize three-level early warning of structural displacement / pressure, reducing operation and maintenance costs by 70%, and extending the overall service life by more than 5 years, forming an ecological-engineering collaborative protection system.

[0024] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A river bank slope protection method for cofferdam construction, characterized by: The following steps are involved: S1, regional adaptability division; S2, construction of structures near the water; S3, far water area structure construction; S4, ecological enhancement.

2. A river bank slope protection method for cofferdam construction according to claim 1, characterized in that: In S1, more specifically: The slope protection area is divided into the near-water area and the far-water area. The near-water area adopts a double-layer reinforced concrete structure, while the far-water area adopts bagged concrete protection. The width of the near-water area is dynamically adjusted according to the water level of the river during the dry season, with an adjustment range of ±2m; The slope angle of the far water area is ≤30°, and a 2m wide transition zone is set at the junction with the existing riverbed.

3. The river bank slope protection method for cofferdam construction according to claim 1, characterized in that: In S2, it also includes: S2-1, double-layer reinforced concrete paving: A 30cm thick C30 reinforced concrete paving layer is laid between railway piers, with a 20cm crushed stone cushion layer underneath. The steel mesh is 100×100mm in a bidirectional arrangement, with a Φ12mm steel mesh specification. 500mm thick reinforcement bars of Φ8mm are installed between the double-layer steel mesh. The concrete slump is controlled at 180±20mm. The paving layer is poured in sections, with a single section length of ≤20m. S2-2, pier skirt protection: 15cm thick C30 reinforced concrete is used for paving between piers, with skirts installed at both ends. The skirts are made of cast-in-place C30 concrete, with a width of ≥1.2m and a height of ≥2.5m from the bottom of the skirt to the riverbed. A 2cm thick elastic sealant with a tensile strength of ≥5MPa is installed between the skirt and the main paving layer; S2-3, clearance control: the clearance between the paved top surface and the bridge is ≥7.6m, the clearance error is ≤±10mm, and a laser rangefinder is used for real-time calibration.

4. The river bank slope protection method for cofferdam construction according to claim 1, characterized in that: In S3-S4, more specifically: Use 15cm thick C20 bagged concrete for slope protection, and set 1m wide maintenance steps every 20m. The compressive strength of the bagged concrete should be ≥15MPa, and the permeability coefficient should be ≤1×10⁻³cm / s. The maintenance steps should use C25 cast-in-place concrete, with a step height of 15cm and a width of 30cm. Φ16mm anti-slip strips should be installed between the steps. A polypropylene grid vegetation mat is composited on the surface of the protective layer, with tall fescue seeds pre-installed in the grid. The humidity is maintained at ≥60% in conjunction with the atomizing spray system to achieve ecological restoration during the construction period. The polypropylene grid aperture is ≤5mm, the unit area mass is ≥300g / m², the anti-ultraviolet aging life is ≥5 years, the grass seed sowing amount is 150g / m², the covering soil thickness is ≤1cm, the atomized particle diameter of the spray system is ≤50μm, the single nozzle coverage radius is ≥3m, and the working pressure is 0.2-0.4MPa.

5. A river bank slope protection construction method for cofferdam construction, characterized by: The following steps are involved: S1, terrain preprocessing; S2, modular assembly near the water; S3, inflation module assembly; S4, module inflation and curing; S5, integrated laying of protective layer; S6, polypropylene grid laying; S7, gravel bag laying; S8, simultaneous implementation of ecological restoration; S9, grass seed sowing; S10, spray curing; S11, dynamic monitoring and adjustment; S12, pressure monitoring; S13, displacement monitoring; S14, abnormal warning.

6. The river bank slope protection construction method of cofferdam construction according to claim 5, characterized in that: In S1-S14, more specifically: In S1, mechanical and manual clearing is used, leaving a 2-3 cm undisturbed soil layer. The clearing depth error is ≤±5 mm. Crawler excavators are used for mechanical clearing, and wooden tamping is used for manual finishing. Rubber protective covers are installed within 2 m around the piers. The thickness of the protective covers is ≥5 mm and the impact strength is ≥20 kJ / m². Said S2 includes S3-S4. In S3-S4, an inflatable honeycomb module is spliced ​​together by NdFeB magnetic locks and nylon straps to form a 2m×1m×0.8m honeycomb structure. The contact surface of the magnetic lock is sandblasted to a roughness Ra ≤ 0.8μm. The contact portion between the nylon strap and the module is provided with an anti-slip buckle with a locking torque ≥ 15N·m. The module is inflated to 0.08MPa through a quick-insert valve and allowed to stand for 24 hours to allow the PVC mesh fabric to set. The inflation process is monitored in real time by a pressure sensor. When the pressure in any air chamber is less than 0.04MPa, air is automatically replenished at a replenishment rate ≤ 0.5MPa / min. The power of the inflation equipment is ≥ 3kW. Said S5 includes S6-S7. In S6-S7, the outer surface of the module is covered with a polypropylene mesh with a pore size of ≤5mm, the mesh is coated with a wear-resistant coating, and the wear rate is ≤5% / 1000h. The mesh and the module are bonded with hot melt adhesive with a bonding strength of ≥2MPa. 30cm thick gravel bags are laid, and the gravel bags are sewn with polyester thread with a wire diameter of ≥2mm. The gravel bags and the mesh are laid alternately with an interval of ≤20cm and a staggered seam of ≥30cm. The gravel bags are made of polypropylene woven cloth with a tensile strength of ≥150kN / m. Said S8 includes S9-S10, in which tall fescue seeds are sown with a soil covering thickness of ≤1 cm, a pneumatic seeder is used for sowing, a sowing uniformity of ≥90%, a sowing speed of ≤0.5 m / s, an atomizing spray system is used to maintain soil moisture ≥60%, a spraying cycle of 8:00-18:00 daily, a HDPE pipe is used for the spray pipe, a nominal pressure of ≥1.0 MPa, and a nozzle atomization angle of ≥120°; The S11 includes S12-S14. In S12-S14, distributed pressure sensors are deployed to monitor the air chamber pressure in real time. The sensor accuracy is ±0.5%, the waterproof grade is IP68, the operating temperature is -20℃~80℃, and the GNSS module is used to monitor the module plane displacement and settlement. The positioning accuracy is ≤2cm. The monitoring data is uploaded to the central control unit through the LoRa protocol. The transmission distance is ≥1km. The central control unit sets three levels of warning thresholds: the first level is a single air chamber pressure of <0.03MPa for >10min, the second level is the maximum displacement of the module >5mm / 24h, and the third level is the ambient temperature >60℃ or the humidity >95%. After the warning is triggered, the sound and light alarm is automatically activated, and a text message is sent to notify the operation and maintenance personnel.

7. The river bank slope protection construction method of cofferdam construction according to claim 6, characterized in that: The distributed sensor includes a pressure sensor, a displacement monitor, and an environmental sensing unit. The pressure sensor has a range of 0-1.5MPa and an accuracy of ±0.5%FS. The displacement monitor has a positioning accuracy of ≤2cm and a data update frequency of ≥1Hz. The central control unit is equipped with an ARM Cortex-A53 processor, runs an embedded Linux system, and supports the Modbus / RTU protocol. The central control unit has a built-in 4G / 5G communication module, a data upload cycle of ≤5min, and is equipped with a UPS backup power supply with a power outage life of ≥72 hours. The early warning trigger establishes a prediction model based on fuzzy logic and neural network, and the early warning response time is ≤1s. The early warning trigger supports customized early warning thresholds and can distinguish between normal operating condition fluctuations and abnormal operating conditions.

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