Vegetable-growing slope surface structure for improving sludge soil through microorganisms and solid waste materials and construction method

Abstract

The invention belongs to the field of civil engineering, and particularly relates to a vegetation slope surface structure for improving sludge soil through microorganisms and solid waste materials and a construction method. The construction method comprises the following steps: spraying an isolating layer: directly spraying a compound bacteria solution containing heavy metal degrading strains on undisturbed soil of the side slope to the surface of the undisturbed soil; pouring a slope protection framework: uniformly mixing sludge, ardealite, fly ash, manganese slag and cement in proportion, and then pouring and molding on the isolating layer through a template; piling up a side slope surface layer: filling silt compost planting soil and grass seeds into the geotechnical ecological bags, and then piling up in the slope surface protection framework; the slope surface structure comprises an isolation layer, a slope surface protection framework arranged on the isolation layer and a geotechnical ecological bag filled in the slope surface protection framework; according to the method, the strength of the soil body is enhanced, the environmental safety is improved, the vegetation adaptability is comprehensively optimized, and a green and safe slope protection approach is provided for slope engineering.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering construction, and in particular relates to a vegetable slope structure and a construction method for improving silt soil by utilizing microorganisms and solid waste materials. Background Art

[0002] Traditional slope covering methods usually use natural soil with good soil properties, which has problems such as limited resources, high costs and environmental impacts. First, natural good soil resources are becoming increasingly scarce, especially in the process of urbanization, and it is increasingly difficult to obtain soil sources suitable for slope covering; second, the mining and transportation of natural soil requires a large amount of labor and mechanical equipment, and the transportation process also faces high costs caused by long-distance transportation; at the same time, soil leakage and dust during transportation will pollute the air, water sources and surrounding vegetation, and soil mining may also cause soil erosion, soil degradation and other problems, affecting the ecological balance of the entire region and increasing the environmental governance burden of the project.

[0003] With the emphasis on sustainable development and resource recycling, using local materials, turning waste into treasure, and using modified silt as slope planting soil has become a hot topic in research and application. Using modified silt as slope planting soil not only reduces the amount of waste disposal, but also provides an economical and efficient solution for slope greening. However, there are still some problems and limitations in the existing silt improvement methods, which affect its quality and environmental safety in engineering applications. Most of the existing silt improvement methods only use one of the physical, chemical or biological methods for treatment, and it is difficult to simultaneously improve the mechanical properties, environmental safety and plant adaptability of the soil. In addition, the amount of solid waste generated in industries such as industry and construction is huge, and the utilization of solid waste resources is still insufficient. Although some methods attempt to apply solid waste materials to silt improvement, the existing methods lack sufficient degradation and fixation measures for the treatment of heavy metals in silt, resulting in possible environmental risks in the modified planting soil. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a vegetable slope structure and construction method for improving silt soil using microorganisms and solid waste materials, so as to solve the problems of unsatisfactory improvement effects caused by the existing silt improvement methods, such as insufficient systematicness, incomplete heavy metal treatment, and lack of guidance on construction technology.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A construction method for a vegetable slope structure using microorganisms and solid waste materials to improve silt soil comprises the following steps:

[0007] Spraying isolation layer: Spraying a composite bacterial solution containing heavy metal-degrading bacteria on the original soil to the surface of the original soil slope. The bacterial solution infiltrates into the slope soil to form a biological heavy metal isolation layer. The heavy metal-degrading bacteria include Bacillus subtilis and Thiobacillus ferrooxidans.

[0008] Casting slope protection skeleton: after the silt, phosphogypsum, fly ash, manganese slag and cement are mixed evenly in proportion, they are cast through the formwork on the isolation layer to solidify into a skeleton of a certain size to form slope protection;

[0009] Stacking slope surface layer: fill the silt compost planting soil and grass seeds into geotechnical ecological bags and fill them into the slope protection frame by artificial stacking. The silt compost planting soil is made by mixing silt with decomposed organic fertilizer, superphosphate and potassium magnesium sulfate fertilizer and then fermenting.

[0010] Furthermore, the silt is mixed with 5%-7% of phosphogypsum by mass, 6%-9% of fly ash, 4-6% of manganese slag and 8-10% of cement at an on-site mixing station for no less than 20 minutes. After being evenly mixed, it is poured into a frame beam-type wooden formwork to form a slope protection skeleton; wherein the phosphogypsum particle diameter is ≤5mm, and the fly ash and manganese slag particle diameters are ≤3mm.

[0011] Furthermore, the silt compost planting soil is obtained by mixing silt with 2.5%-3.5% of decomposed organic fertilizer, 1%-1.2% of superphosphate and 0.5%-0.9% of potassium magnesium sulfate fertilizer and then stacking and fermenting.

[0012] Furthermore, in the isolation layer, the moisture content of the original soil of the slope is controlled to 12%-15%; the amount of the composite bacterial solution sprayed on the original soil of the slope is 2.1-2.55L / m 2 ;

[0013] When preparing the composite bacterial solution, a 2% concentration of Bacillus subtilis bacterial solution and a 4% concentration of Thiobacillus ferrooxidans bacterial solution are prepared respectively, and then the two are mixed in a volume ratio of (2-3): (5-5.5) to obtain the composite bacterial solution.

[0014] Furthermore, the sludge in the slope protection framework and the slope surface layer is pond sludge; before mixing the sludge, the sludge water content is reduced to 40%-50% by a filter press, and then the dehydrated sludge cake is spread in the dehydration area for drying until the sludge water content is reduced to 35%-40%; the daily processing capacity of the filter press is not less than 25m 3 ; The straight-line distance from the dewatering area to the sludge source shall not exceed 50m.

[0015] Furthermore, when the silt compost planting soil material is piled up for fermentation, the height of the pile shall not exceed 2m and the top of the pile shall be arc-shaped; during the fermentation process, the pile shall be turned over every 2-3 days to ensure that the temperature of the pile is maintained within the range of 45℃-65℃; the pile shall be piled up for no less than 7 days to ensure sufficient fermentation, and finally form granules with uniform structure, no odor and loose and uniform shape.

[0016] Furthermore, ensure that the composite bacterial liquid spraying equipment is calibrated to ensure that the spraying amount per square meter is accurate; after spraying and maintenance, use the total station and GPS system to measure the slope in detail and build the slope frame beam type wooden formwork; record the slope height as H meters, when building the frame beam type wooden formwork, set positioning piles every 5 meters in the horizontal direction, set a horizontal support beam every H / 3 slope height in the vertical direction, add support rods every 2 meters vertically, and add corner wood reinforcement at the corners and edges.

[0017] Furthermore, after the construction of the slope surface layer is completed, a drainage ditch is set at the foot of the slope along the contour line direction, and a seepage pipe is set as needed to ensure the drainage function; the length of the slope foot is 2-4m; the drainage ditch is 25-35cm wide and 15-25cm deep, and the slope is not less than 1%.

[0018] Furthermore, in the isolation layer, the moisture content of the original soil of the slope was 12.5%, and 0.75L of 2% Bacillus subtilis solution and 1.5L of 4% Thiobacillus ferrooxidans solution were sprayed per square meter of the original soil of the slope;

[0019] In the slope protection skeleton, the mass percentage of each component in the silt is: 6.0% phosphogypsum, 7.5% fly ash, 5.0% manganese slag, and 8% cement;

[0020] In the slope surface layer, the mass percentage of each component in the silt is: 3.0% of decomposed organic fertilizer, 1.1% of superphosphate, 0.7% of potassium magnesium sulfate fertilizer, and the paving thickness is 30cm.

[0021] The present invention also proposes a vegetable slope structure using microorganisms and solid waste materials to improve silt soil, which is manufactured using the aforementioned construction method for the vegetable slope structure using microorganisms and solid waste materials to improve silt soil, comprising:

[0022] The isolation layer is formed by spraying the composite bacterial solution on the original soil of the slope and allowing the bacteria in the composite bacterial solution to fully penetrate to a certain depth; the composite bacterial solution contains Bacillus subtilis and Bacillus ferrooxidans;

[0023] A slope protection frame, wherein the slope protection frame is arranged on the isolation layer and is constructed by casting with a frame beam type wooden formwork. The raw materials of the slope protection frame include silt and 5%-7% of phosphogypsum, 6%-9% of fly ash, 4-6% of manganese slag and 8-10% of cement, which accounts for 5%-7% of the weight of the silt;

[0024] The slope surface layer is formed by stacking geo-ecological bags filled with silt compost and grass seeds. These geo-ecological bags are filled in layers into the slope protection frame that has been built, and 2-3 layers are laid as needed; in the silt compost, the percentage of each component in the silt mass is: 2.5%-3.5% of decomposed organic fertilizer, 1%-1.2% of superphosphate, and 0.5%-0.9% of potassium magnesium sulfate fertilizer.

[0025] The beneficial effects of the present invention are:

[0026] The present invention adopts a three-layer treatment method for slope planting soil, using the original slope soil and silt as raw materials in different soil layers, and adding specific modified materials and functional microorganisms. The isolation layer is mixed with heavy metal degrading bacteria to build a stable soil barrier to prevent heavy metals in solid waste from migrating downward, while enhancing the isolation performance of the bottom soil;

[0027] The slope protection frame plays a role in anti-scouring on the one hand, and on the other hand, it serves as a framework to improve the physical and mechanical properties of the pond sludge and to install it in the geobag, ensuring that the geobag will not slide significantly while improving the anti-scouring ability;

[0028] The surface layer of the slope uses fermented sludge compost to plant soil, optimizes the nutrient structure and microbial activity of the sludge, and provides ideal soil and nutrients for vegetation growth. The present invention realizes the improvement and utilization of sludge, enhances the strength of sludge, improves environmental safety, and comprehensively optimizes the adaptability of vegetation, provides high-performance raw materials for slope engineering, does not require soil mining, and can realize the comprehensive utilization of solid waste materials such as sludge, phosphogypsum, fly ash, and manganese slag, which is beneficial to environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0030] Figure 1 It is a schematic diagram of the structure of slope planting soil according to an embodiment of the present invention.

[0031] In the figure: 1-drainage ditch, 2-planting layer, 3-heavy metal isolation layer, 4-slope protection frame. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0033] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0034] A construction method for a vegetable slope structure using microorganisms and solid waste materials to stabilize and solidify silt soil, comprising the following steps:

[0035] The composite bacterial liquid containing heavy metal degrading bacteria is sprayed onto the surface of the original soil. The bacterial liquid infiltrates into the slope soil to form a biological heavy metal isolation layer. The heavy metal degrading bacteria include Bacillus subtilis and Thiobacillus ferrooxidans. During spraying, the moisture content of the original slope soil is controlled at 12%-15%, the concentrations of Bacillus subtilis and Thiobacillus ferrooxidans are controlled at 2.0% and 4.0%, respectively. The original slope soil is sprayed with 0.6-0.9L / m 2 and 1.5-1.65 L / m 2 of bacterial liquid;

[0036] Casting slope protection skeleton: Use the template to build the slope protection skeleton structure to ensure the high strength and stability of the protection skeleton; the mass percentage of each component in the sludge is: 5%-7% of phosphogypsum, 6%-9% of fly ash, 4-6% of manganese slag, 3%-5% and 8-10% of cement are mixed evenly according to the designed proportion; during the mixing process, the moisture content of the sludge is strictly controlled at 30%-35%, and the moisture content of the overall mixture is controlled at 12%-15%;

[0037] Stacking the surface layer of the slope: fill the silt composting soil and grass seeds into geotechnical ecological bags and fill them into the slope protection skeleton frame by artificial stacking; the silt composting soil is made by mixing silt with decomposed organic fertilizer, superphosphate and potassium magnesium sulfate fertilizer and fermenting; the percentage of each component in the silt composting soil is as follows: decomposed organic fertilizer 2.5%-3.5%, superphosphate 1%-1.2%, potassium magnesium sulfate 0.5%-0.9%; the slope structure after construction is completed is as follows Figure 1 shown.

[0038] The present invention also proposes a vegetable slope structure for improving silt soil by using microorganisms and solid waste materials, comprising:

[0039] The isolation layer is formed by spraying the composite bacterial solution on the original soil of the slope and allowing the bacteria in the composite bacterial solution to fully penetrate; the composite bacterial solution contains Bacillus subtilis and Bacillus ferrooxidans;

[0040] A slope protection frame, wherein the slope protection frame is arranged on the isolation layer and is constructed by casting with a frame beam type wooden formwork. The raw materials of the slope protection frame include silt and 5%-7% of phosphogypsum, 6%-9% of fly ash, 4-6% of manganese slag and 8-10% of cement, which accounts for 5%-7% of the weight of the silt;

[0041] The slope surface layer is formed by stacking geo-ecological bags filled with silt compost and grass seeds, which are filled in layers into the slope protection frame that has been built; 2-3 layers are laid as needed; in the silt compost, the mass percentage of each component in the silt is: 2.5%-3.5% of decomposed organic fertilizer, 1%-1.2% of superphosphate, and 0.5%-0.9% of potassium magnesium sulfate.

[0042] Next, the specific construction method of the present invention is described in detail with reference to the embodiments.

[0043] A construction method for using improved silt as slope planting soil includes five stages: S1 preliminary preparation, S2 silt dehydration, S3 silt fermentation modification, S4 slope planting soil construction, and S5 vegetation construction.

[0044] In some embodiments, the specific implementation process of the preliminary preparation of step S1 is:

[0045] S11. Select the location of the dewatering area; select it within 50m around the sludge source to shorten the transportation distance and improve work efficiency; conduct topographic survey and select a location with flat terrain and 0.5m higher than the surrounding area as the dewatering area to ensure smooth drainage.

[0046] S12. Clear the surface vegetation and debris on the site and lay a 10cm gravel cushion to increase foundation stability.

[0047] S13. Dig drainage ditches 30cm wide and 30cm deep around the dehydration area, lined with an impermeable membrane, and drain the wastewater generated by dehydration to a capacity of no less than 10m 3 Wastewater collection pool; the wastewater collection pool body adopts reinforced concrete structure, and the inner wall is painted with anti-seepage paint.

[0048] S14. Selection of belt filter press: Select a belt filter press with a daily processing capacity of not less than 25 cubic meters, and the equipment must have a continuous dehydration function to ensure that the moisture content of the sludge is reduced from 60%-80% to 40%-50%, providing suitable mud conditions for subsequent modification of the sludge.

[0049] S15. Install the belt filter press on the reinforced concrete foundation that has been cast in advance and cured for 7 days; the reinforced concrete foundation size is 1.5 times the bottom area of ​​the belt filter press, the thickness is not less than 30cm, and it contains a steel mesh with a diameter of 12mm and a spacing of 20cm.

[0050] S16. Use a level to calibrate the flatness of the reinforced concrete foundation, with an error of no more than ±5mm. A 5cm thick rubber shock-absorbing pad is installed at the bottom of the belt filter press to prevent ground settlement or equipment deviation caused by operating vibration.

[0051] S17. Use anchor bolts with a diameter of not less than 16mm to fix the belt filter press on the reinforced concrete foundation. According to the layout of the belt filter press, connect the 150mm diameter mud inlet pipe and the 100mm diameter drainage pipe. The pipes are connected by flanges and equipped with rubber sealing rings. The joints are tightened to the torque value specified by the manufacturer.

[0052] S18. After completion, conduct a pipeline pressure test to ensure there is no mud or water leakage;

[0053] After the belt filter press is installed, it is debugged with and without load. First, it is debugged with no load, and the equipment is started and run for 30 minutes. The operation of the electrical system, transmission components and filter belt is checked to ensure that there is no abnormal noise or vibration, and the motor temperature rise is within the normal range.

[0054] Then, the load test was carried out, and the sludge was gradually introduced, with the initial flow rate being 50% of the design value, and the water filtration effect and the moisture content of the sludge were observed;

[0055] During the debugging process, a moisture tester is used to take samples and test every 30 minutes to ensure that the moisture content of the mud is stable at 40%-50%; according to the test results, the mud input, filter belt speed and tension of the equipment are adjusted, and various parameters are recorded to ensure that the equipment can run continuously and stably for more than 8 hours at full load to meet construction needs.

[0056] In some embodiments, the specific implementation process of step S2 sludge dehydration is:

[0057] S21. Before the formal dehydration operation, check the mechanical and electrical components of the belt filter press. Control the tension of the filter belt at 15-20N / mm; lubricate all transmission components; install a filter screen with an aperture of no more than 5mm at the feed inlet to prevent impurities from entering; start the equipment, gradually open the mud inlet valve, and control the mud inlet pressure within the range of 0.1-0.3MPa.

[0058] S22. Monitor the clarity of the filtrate in real time, and regularly sample and test the suspended matter content to ensure that the discharge meets the standards. According to the moisture content of the mud, adjust the filter belt speed and compression force to keep the moisture content of the mud at 40%-50%. Record the operating parameters and test data every hour to ensure that the dehydration process is stable and efficient.

[0059] S23. After dehydration, the dehydrated mud cake is evenly spread in the dehydration area through a conveyor belt, with a thickness of 30-50cm. The ground of the dehydration area has been made of concrete or paved with an impermeable membrane, and a drainage slope of 2% is set to meet the drying requirements.

[0060] S24. After the mud cake is spread, check the moisture content of the sludge every 2-3 hours, and use mechanical turning equipment to turn the mud cake in the dehydration area to increase the evaporation efficiency until the sludge moisture content drops to 35%-40%, providing suitable mud conditions for subsequent construction. After spreading, record the weather conditions of the day. If the temperature is above 15℃ and the humidity is low, it is a weather condition that is conducive to water evaporation; when the humidity is high or it is rainy, the drying time can be appropriately extended to 8-12 hours.

[0061] In some embodiments, the specific implementation process of step S3 of obtaining sludge compost planting soil by fermentation and modification of sludge is as follows:

[0062] S33. Evaluate and clean the transport routes according to construction requirements, and lay steel plates or gravel roadbeds on soft sections when necessary to increase the road's bearing capacity and prevent vehicles from getting stuck or damaging the road surface;

[0063] During transportation, use a loader or closed transport vehicle with a load not exceeding 80% of the rated capacity of the equipment, and strictly control the vehicle speed within 10km / h to ensure transportation safety and avoid pollution caused by sudden braking or sharp turns.

[0064] S34. After the sludge is transported to the construction site, it will be unloaded to the stockpiling area. The stockpiling area should be located in a flat and well-drained area, with an anti-seepage membrane of not less than 1.5 mm thickness laid on the ground, and a cofferdam of 0.5 m in height set around it to prevent the leakage of leachate.

[0065] S35. When unloading sludge, it must be piled evenly, with the pile height controlled not to exceed 2m, and the distance between piles must be kept at 1m to facilitate ventilation and subsequent processing.

[0066] S36. A special fermentation area is set up in the stockpile area for mixing and fermentation of sludge compost and planting soil. The area of ​​the fermentation area is planned according to construction requirements and is usually set to 15-30m 2 An impermeable membrane is laid on the ground of the fermentation area and a liquid collection ditch is set up. The liquid collection ditch is connected to the sedimentation tank or wastewater collection system to treat the leachate generated during the fermentation process.

[0067] S37. In the fermentation area, add 3.0% of decomposed organic fertilizer, 1.1% of superphosphate and 0.7% of potassium magnesium sulfate fertilizer per cubic meter of pond sludge. Use a mechanical mixer or loader to mix evenly and pile it up. The pile height should not exceed 2m, and the top should be in an arc shape to facilitate drainage. After mixing, fermentation management should be carried out to ensure that suitable sludge compost planting soil is formed.

[0068] S38. During the fermentation process, the pile is turned over every 2-3 days to ensure good ventilation inside and promote uniform fermentation. Turning can be done using a compost turner or loader, while monitoring the temperature and humidity of the pile to ensure that the temperature of the pile remains within the range of 45-65°C and that the humidity is appropriate and does not stick together. Thermometers should be installed in the middle and top of the pile to regularly record temperature changes, and the humidity can be adjusted by spraying water or covering with a breathable tarpaulin when necessary. Ventilated fermentation is used in this embodiment to ensure sufficient oxygen supply and promote balanced degradation of organic matter;

[0069] S39. Spray biological deodorant on the pile or cover it with breathable tarpaulin to reduce the impact on the environment. The pile should be piled for no less than 7 days to ensure full fermentation, and finally form a material with uniform structure, no odor and suitable physical state, which is sludge compost planting soil;

[0070] After fermentation is completed, the fermentation effect of the material is checked to ensure that the color of the pile is uniform, there are no uncomposted particles, the moisture content is controlled at 30%-35%, the material needs to be loose and uniform granules, and there is no obvious odor. Before transfer, the pile batches and fermentation time are classified and recorded to ensure traceability.

[0071] In some embodiments, the specific implementation process of step S4 slope planting soil construction is:

[0072] S41. Prepare a bacterial solution using finished bacterial strains. This embodiment uses 100 billion / g of Bacillus subtilis strains from Yiqiang Biology and second-generation active Thiobacillus ferrooxidans cultured in Shandong Top Biological Culture Medium; when preparing the Bacillus subtilis bacterial solution, accurately weigh 1.0 g of highly active bacterial cells, add them to 49.0 mL of distilled water or nutrient solution, and use a mechanical stirrer to fully stir to ensure that the bacterial cells are evenly distributed to form a uniform suspension, and obtain a Bacillus subtilis bacterial solution with a concentration of 2%, which is recorded as bacterial solution A; when preparing the Thiobacillus ferrooxidans bacterial solution, accurately weigh 6.3 g of highly active Thiobacillus ferrooxidans bacterial cells, add them to 193.7 grams of distilled water or nutrient solution, and fully stir to obtain a Thiobacillus ferrooxidans bacterial solution with a concentration of 4%, which is recorded as bacterial solution B.

[0073] S42, after the bacterial solution A and the bacterial solution B are prepared, the bacterial solution A and the bacterial solution B are mixed in a volume ratio of (2-3): (5-5.5) to prepare a composite bacterial solution; preferably, the spraying amount of the original soil of the slope is: 0.6-0.9 L / m of bacterial solution A2 , bacterial solution B is 1.5-1.65L / m 2 , then the spraying amount of the composite bacterial solution is 2.1-2.55L / m 2 ;

[0074] Use a positive displacement pump to spray the composite bacterial solution directly onto the original soil surface of the slope at a pressure of 2.5 bar and a flow rate of 80 ml / min; spray evenly in different areas from top to bottom and from one side to the other; use metering equipment to accurately control the spraying amount to ensure that the composite bacterial solution is evenly distributed; ensure that the spraying equipment is calibrated to ensure that the spraying amount per square meter is accurate;

[0075] Before construction, confirm that the moisture content of the original soil of the slope is between 12% and 15%. If the moisture content is too low, use a water spraying device to spray an appropriate amount of clean water to adjust it to the designed range. Choose an appropriate construction time and avoid spraying in extreme weather to ensure effective coverage and action of the bacterial solution.

[0076] S43. After the spraying of the composite bacterial solution is completed, use plastic film to cover the slope area to maintain appropriate humidity, promote the growth and reproduction of the bacterial community, and prevent rain or excessive sunlight from directly affecting the sprayed bacterial solution to ensure its stability in the soil.

[0077] S44. After covering, leave at least 48 hours of interval time to wait until the original soil of the slope and the heavy metal degrading bacteria are fully solidified and the bacterial community is colonized, that is, a biological heavy metal isolation layer is formed, and then the next stage of construction operation can be carried out.

[0078] S45. Use the total station and GPS system to measure the slope in detail and build the formwork. Use the frame beam wooden formwork on the slope with a height of H meters, and divide it into several layers according to the verticality of the slope;

[0079] The unit grid is set according to the size of the slope and the terrain conditions, such as 2m×2m, 2m×4m, 3m×2m and other sizes; 20mm thick, 2m long, 30cm deep wooden boards are used as frame beam wooden formwork materials; the formwork reserves a margin of about 1-2cm so that the formwork can fit the slope tightly and remain stable through wooden wedges or fine-tuning supports during on-site installation; positioning piles are set every 5 meters in the horizontal direction, and a horizontal support beam is set every H / 3 slope height in the vertical direction. When the formwork is installed piece by piece, adjacent plates are fixed with steel nails, and the intersection of the grid is connected through bolts with a diameter of 12 mm to enhance the overall rigidity; support rods are added vertically every 2 meters, and corner wood is added at the corners and edges for reinforcement; after the installation is completed, a level is used to calibrate the flatness and inclination of the formwork.

[0080] S46. At the construction site, pond sludge with a moisture content of 35% is uniformly mixed with 6.0% phosphogypsum, 7.5% fly ash, 5.0% manganese slag and 8% cement according to the designed proportion per cubic meter of pond sludge; the moisture content of pond sludge is controlled at 30%-35%; phosphogypsum must be a powder with a particle diameter of ≤5mm, fly ash and manganese slag must be sieved in advance with a particle diameter of ≤3mm; PO 42.5 cement is used; the mixing operation uses on-site mechanical stirring, the stirring time is not less than 20 minutes, and it is ensured that there is no material separation during the mixing process, and the moisture content after mixing is controlled at 12%-15%.

[0081] S47. Use a filling pump to evenly fill the mixed skeleton material into the installed formwork frame. The thickness of each filling layer should be controlled between 10-15cm to ensure uniform coverage and full bonding of the material. During the filling process, use a trowel or spatula to manually smooth the filling material to avoid the formation of voids or uneven areas.

[0082] S48. After the filling construction is completed, reserve at least 24 hours for the filling material to cure and combine naturally. The specific curing time should be adjusted appropriately according to environmental conditions such as temperature and humidity. The strength after curing can reach C25 level. Use plastic film to cover the filling area to maintain humidity and prevent rain or excessive sunlight from directly affecting the curing process.

[0083] S49. After the filling material reaches the initial solidification, carefully remove the formwork frame to ensure that the slope protection skeleton that has been formed is not damaged. Use demoulding tools such as pliers, wrenches or hammers to smoothly dismantle the steel or wooden formwork and remove it step by step to avoid impact or damage to the skeleton. After removing the formwork, use a level to measure the surface flatness to ensure that it meets the design slope requirements (2% drainage slope).

[0084] S410, weigh the grass seeds and silt compost planting soil at 1m 3 Stir 1-2 kg of grass seeds into the compost evenly to obtain grass seed-compost material; use a mechanical mixer to stir at medium speed for 5-8 minutes to ensure that the grass seeds are evenly distributed in the silt compost planting soil.

[0085] S411. Use breathable geotechnical eco-bags with specifications of 80cm×50cm and thickness of 0.5-0.8mm. When choosing geotechnical bags, strictly use synthetic fiber geotechnical bags with standard specifications of 80cm×50cm, with a weaving density of ≥60 strands / 10cm and a tensile strength of ≥10kN / m. Put the mixed grass seed-compost materials into the bags, and control the filling weight of each bag to 20-25kg. Use electronic scales for calibration during bagging, and the error shall not exceed ±5%.

[0086] S412. Fill the filled geotechnical eco-bags in layers into the built protective frame. Each layer of bags should fit tightly, with no gap greater than 1 cm between bags. When laying horizontally, keep the flatness of the bag surface within ±10 mm. After laying 3 layers of bagged materials, the final surface elevation error should be controlled within ±20 mm.

[0087] S413. After the construction of the slope surface layer is completed, the drainage ditch is excavated along the slope foot contour line. The width of the drainage ditch is 30cm, the depth is 20cm, and the slope is not less than 1%. During the excavation of the drainage ditch, it is necessary to ensure that the slope ditch wall is stable, the bottom is flat and there is no water accumulation, and the drainage function is smooth and unobstructed. The drainage ditch is connected to the overall drainage system of the slope to ensure that rainfall or seepage water can be discharged in time. After the construction is completed, use a slope gauge to check the slope bottom and drainage effect to ensure that there is no reverse slope at the bottom of the slope and meet the design drainage function requirements.

[0088] The embodiments of the present invention have the following advantages:

[0089] (1) The comprehensive performance of sludge is significantly improved after modification: a systematic and multi-level modification method is adopted, and specific modified materials and functional microbial agents are added to different soil layers. In the isolation layer spraying stage, Bacillus subtilis and Bacillus ferrooxidans microbial strains are accurately prepared and evenly sprayed on the original soil surface of the slope, and the concentration of the bacterial solution, the spraying amount and the soil moisture content are strictly controlled to achieve more efficient biodegradation and fixation of heavy metals. The slope protection skeleton introduces solid waste materials such as phosphogypsum, fly ash, manganese slag and cement, and strictly controls the moisture content, effectively enhancing the strength and anti-scouring ability of the soil. The surface layer of the slope is made of sludge compost planting soil and grass seeds filled in geotechnical ecological bags, providing a growth medium with uniform structure, excellent air permeability and suitable nutrients for vegetation growth, and realizing the comprehensive optimization of sludge strength, environmental safety and vegetation adaptability. The present invention achieves the overall enhancement of soil strength, improvement of environmental safety and comprehensive optimization of vegetation adaptability, providing a green and safe protection method for slope engineering.

[0090] (2) Improve construction efficiency and standardization: A systematic operation plan for the entire process from sludge dehydration, modification treatment to layered construction was proposed. By scientifically selecting the dehydration area, optimizing the drainage system, and using high-efficiency belt filter presses and mechanical turning technology, the sludge moisture content was quickly reduced to 35%-40%. During the construction process, the fermentation area was rationally planned and mechanized mixing and turning methods were adopted to improve the fermentation efficiency and uniformity of the modified materials. During the on-site construction, the slope was layered and strictly followed the steps of spraying bacterial liquid on the isolation layer, building a slope protection skeleton with solid waste mixture, and bagging the compost and grass seed mixture into the skeleton. The standardized construction process not only improves efficiency, but also ensures the controllability and consistency of construction quality, avoiding random errors in manual operations.

[0091] (3) Enhance slope stability and safety: Use frame beam wooden formwork to build a slope protection skeleton, and establish a stable slope protection skeleton structure that can accurately correct flatness and inclination. The uniform spraying of the composite bacterial liquid, the layered filling of the modified materials, and the filling of the compost bags are all carried out in an orderly manner within this slope protection skeleton, which improves the density, uniformity and overall stability of the slope and reduces the risks of landslides, subsidence and erosion.

[0092] (4) Effectively utilize solid waste resources and promote green construction: Solid wastes such as phosphogypsum, fly ash, and manganese slag are introduced into the stabilization layer to realize the resource utilization of solid waste and reduce the cost of engineering materials. At the same time, during the fermentation process of sludge compost planting soil, the odor pollution to the surrounding environment during the fermentation process is reduced through ventilation and temperature and humidity monitoring. The construction area adopts an impermeable membrane and cofferdam design to prevent leachate from polluting the surrounding soil and water, providing effective protection for green construction.

[0093] Next, the material design of the isolation layer, the stabilization layer and the slope surface layer in the present invention is described in conjunction with the following experimental examples.

[0094] In Experimental Examples 1-3, setting weakly acidic, neutral, and weakly alkaline pH gradients and measuring the final pH to obtain pH change conclusions can provide theoretical basis and guidance for application scenarios with different purposes. In actual construction, there is no need to specifically adjust the pH.

[0095] Experimental Example 1

[0096] Experimental Example 1 aims to evaluate the effects of different bacterial species ratios, original soil moisture content, and pH value of the isolation layer raw materials on the heavy metal content.

[0097] Experimental design: Orthogonal experimental design was adopted, and a blank control group (CK1) was set. The experimental design is shown in Table 1. The thickness of the original slope soil mixed with the bacteria was set to 30 cm. The moisture content of the original soil in the blank control group (CK1) was 12.5%, the pH value was 7.0, and no Bacillus subtilis and Bacillus ferrooxidans were added.

[0098] Table 1 Orthogonal experimental design of isolation layer raw materials

[0099] factor Level 1 Level 2 Level 3 <![CDATA[Bacillus subtilis (g / m 3 )]]> 40 50 60 <![CDATA[Acidithiobacillus ferrooxidans (g / m 3 )]]> 180 200 220 Water content of original slope soil (%) 10 12.5 15 pH 6.5 7.0 7.5

[0100] Experimental steps:

[0101] (1) Sample preparation: Cultivate the bacterial strain to ensure that the activity and concentration meet the experimental requirements. Collect the original soil from the same source and sieve it to less than 2 mm; adjust the moisture content of the original soil according to the experimental design.

[0102] According to the experimental design, hydrochloric acid and sodium hydroxide solutions were used to adjust the pH value of the original slope soil.

[0103] (2) Sample mixing: Add Bacillus subtilis and Bacillus ferrooxidans according to the experimental design, stir at a low speed to mix evenly, and control the mixing time within 10 minutes to avoid excessive stirring that may cause damage to the soil structure.

[0104] (3) Fermentation treatment: The mixed samples were placed in a sealed container and fermented in a fermentation box for 7 days under the optimal conditions for the strain. The purpose of this experiment to perform short-term fermentation treatment on the samples is to enable them to reach a relatively stable survival state in a relatively short period of time and ensure the stability of the test.

[0105] (4) Sample testing: Use a heavy metal analyzer (such as an atomic absorption spectrometer) to determine the content of lead (Pb), cadmium (Cd), and mercury (Hg) in the sample; perform sample pretreatment in accordance with national or industry standards.

[0106] The final pH value of the sample was determined using a well-calibrated pH meter. The purpose of measuring the pH value was to obtain the pH difference before and after the test. The pH value was basically kept within a stable range, indicating that the experimental group had good stability.

[0107] Experimental results: The experimental results are shown in Table 2.

[0108] Table 2 Orthogonal test results of isolation layer materials

[0109]

[0110] As shown in Table 2, with the increase of the addition of Bacillus subtilis and Thiobacillus ferrooxidans, the Pb content decreased overall, but the Pb content was higher at high water content and low pH value; adding bacteria and moderate pH value helped to reduce Cd content; adding bacteria and moderate pH value reduced Hg content, but high water content may lead to increased Hg release. The Pb, Cd, and Hg contents of experimental group 15 were the lowest, and those of experimental group 6 were the highest.

[0111] The pH value of the experimental group ranged from 6.4 to 7.6, and that of the control group was 7.0. Some experimental groups achieved an increase in pH by adding bacteria and adjusting pH, but the effect was not good under extreme conditions (high water content and low pH).

[0112] Taking into account the heavy metal content and the final pH value, the optimal ratio is experimental group 14. This is because the optimal growth pH of Bacillus subtilis and Bacillus ferrooxidans is concentrated in the neutral and slightly acidic range of 6.5-7.0, while the final pH value of experimental group 15 is 7.6, which is not conducive to the growth of Bacillus subtilis and Bacillus ferrooxidans. 3 , Thiobacillus ferrooxidans 200g / m 3, original soil moisture content 12.5%, original soil pH 7.0, final pH 7.2, its effect on reducing heavy metals was slightly less than that of experimental group 15, but its final pH could remain relatively stable.

[0113] The optimal strain dosage in experimental group 14 was converted, and the dosage of Bacillus subtilis per square meter of original slope soil was 50g / m 3 ×0.3m÷2%=750mL / m 2 The dosage of Thiobacillus ferrooxidans per square meter of original soil on the slope is 200g / m 3 ×0.3m÷4%=1500mL / m 2 .

[0114] Experimental Example 2

[0115] Experimental Example 2 aims to evaluate the effects of different proportions of phosphogypsum, fly ash, manganese slag, cement and pH value on the unconfined compressive strength and internal friction angle of the stabilized layer.

[0116] Experimental design: Orthogonal experimental design was adopted. The experimental design is shown in Table 3.

[0117] Table 3 Orthogonal experimental design of stabilization layer raw materials

[0118] factor Level 1 Level 2 Level 3 Phosphogypsum addition amount (%) 5.0 6.0 7.0 Fly ash addition amount (%) 6.0 7.5 9.0 Manganese slag addition amount (%) 4.0 5.0 6.0 Cement addition amount (%) 8.0 9.0 10.0 pH 7.0 7.5 8.0

[0119] Experimental steps:

[0120] (1) Sample preparation: According to the experimental design, accurately weigh each additive; adjust the pH value of the raw material mixture with hydrochloric acid and sodium hydroxide solution.

[0121] The water content of the sludge is 35%. Use pond sludge with less impurities without screening; mix the pond sludge with the weighed additives according to the designed ratio; use a mixer to stir at medium speed for 15 minutes to ensure that the additives are evenly distributed in the sludge.

[0122] (2) Sample preparation: The mixed stabilization layer material is placed in a standard mold and tested after curing for a certain period of time (e.g., 7 days). The test conditions are carried out in accordance with relevant standards (e.g., ASTM D4440).

[0123] (3) Sample testing: Use a compression tester to measure the unconfined compressive strength of the sample. Use a shear tester or direct shear method to measure the internal friction angle of the sample.

[0124] Experimental results: The experimental results are shown in Table 4.

[0125] Table 4 Results of orthogonal experiment on stable raw materials

[0126]

[0127]

[0128] As can be seen from Table 4, the unconfined compressive strength shows a gradual upward trend with the appropriate increase in the amount of phosphogypsum and fly ash (experimental groups 11-15, experimental groups 22-24, etc.). However, when the amount of phosphogypsum increased from 6.0% to 7.0% (experimental groups 20-24), the increase in the unconfined compressive strength gradually decreased or even stabilized, indicating that phosphogypsum may be close to the optimal addition amount around 6.0%; 7.5% fly ash has a more significant improvement in compressive strength (experimental groups 13, 14, and 15 compared to experimental groups 10, 11, and 12), and when it is too high (9%), it may produce a saturation effect (experimental groups 16-18).

[0129] The internal friction angle reached a high level when the manganese slag was 5.0% and the pH value was 7.5-8.0 (shown in experimental groups 14, 15, 17, etc.). Too high a proportion of manganese slag (experimental groups 25-27) did not significantly increase the internal friction angle; 8.0% cement (experimental groups 14 and 20) was used as the basic cementitious material, and its stabilizing effect effectively increased the internal friction angle, but the effect tended to weaken after it continued to increase to 10% (experimental groups 25, 26, and 27).

[0130] Taking into account the unconfined compressive strength, internal friction angle, Ph value and economy, the optimal mix ratio is 6.0% phosphogypsum, 7.5% fly ash, 5.0% manganese slag and 8.0% cement.

[0131] Experimental Example 3

[0132] Experimental Example 3 aims to evaluate the effects of different ratios and paving thicknesses of raw materials in the slope surface layer on heavy metal content and plant growth.

[0133] Experimental design: Orthogonal experimental design was adopted, and a blank control group (CK3) was set up. The experimental design is shown in Table 5. The sludge moisture content of the blank control group (CK3) was 35%, the pH value was 2 (the original pH value of the sludge), the paving thickness was 30 cm, and no decomposed organic fertilizer, superphosphate and potassium magnesium sulfate fertilizer were added.

[0134] Table 5 Orthogonal experimental design of slope surface layer materials

[0135] factor Level 1 Level 2 Level 3 Amount of decomposed organic fertilizer added (%) 2.5 3.0 3.5 Superphosphate addition amount (%) 1.0 1.1 1.2 Potassium magnesium sulfate fertilizer addition amount (%) 0.5 0.7 0.9 Paving thickness (cm) 25 30 35

[0136] Experimental steps:

[0137] (1) Sample preparation: According to the experimental design, accurately weigh each additive; adjust the pH value of the raw material mixture with hydrochloric acid and sodium hydroxide solution. The water content of the sludge is 35%. Mix the pond sludge with the weighed additives according to the designed proportion; use a mixer at medium speed for 15 minutes to ensure that the additives are evenly distributed in the sludge.

[0138] (2) Fermentation treatment:

[0139] Sampling: Load the mixed slope surface layer material into the container in the fermentation box, ensuring that the container is well sealed to prevent external contamination.

[0140] Control fermentation conditions: Set the temperature to 45-65℃, and adjust it according to the properties of fertilizer and sludge. Keep the humidity within the appropriate range, avoiding excessive dryness or wetness.

[0141] Fermentation period: 7 days of fermentation, during which the temperature and humidity are monitored and the data is recorded every day. If the temperature or humidity deviates from the set range, the fermentation box conditions are adjusted in time.

[0142] In this experimental example, the purpose of using sealed fermentation treatment is to accurately control the oxygen concentration and humidity in the experimental environment, ensure that the experimental conditions are accurately controllable, and thus analyze the differences in the effects of variables such as admixtures and organic fertilizers on soil covering performance.

[0143] (3) Sample spreading and vegetation planting:

[0144] Spread the fermented slope surface layer material in the test device according to the designed thickness, ensure uniform spreading and maintain a 2% drainage slope; the test device includes a slope built to simulate the actual construction environment. Use the artificial planting method to dig holes at a spacing of 20cm and a depth of 3-5cm, plant Bermuda grass and ryegrass seeds, cover the soil and gently compact it. Plant water celery at the foot of the slope with a spacing of 30cm and a depth of 5-10cm. After planting, use a fine mist sprinkler to evenly water the soil to keep it moist to the field water holding capacity; cover with straw or non-woven fabrics when necessary to prevent soil erosion. Measure the plant height and growth every week, observe the health of the vegetation, and carry out replanting and pest control in a timely manner.

[0145] (4) Sample testing: Soil samples were randomly collected from each experimental group, and the content of lead (Pb), cadmium (Cd), and mercury (Hg) in the samples was determined using a heavy metal analyzer (such as an atomic absorption spectrometer). The final pH value of the sample was determined using a well-calibrated pH meter. On the 14th day after sowing, the rhizome height and growth were recorded. When measuring the rhizome height per plant, 5 healthy plants were randomly selected from each experimental group as measurement samples; first, the small lateral roots, leaves, and adhering soil were removed, and the main root and thick secondary roots were retained. A vernier caliper was used to measure the length from the base of the rhizome to the tip of the main root, and the average value was recorded to obtain the rhizome height per plant; then the plants were weighed, the average value was calculated, and the growth was obtained.

[0146] Experimental results: The experimental results are shown in Table 6.

[0147] Table 6 Results of orthogonal experiment on stable raw materials

[0148]

[0149] From the experimental results in Table 6, we can see that:

[0150] ① The plant height range is 12cm-25cm. Adding decomposed organic fertilizer and appropriate fertilizer (superphosphate, potassium magnesium sulfate fertilizer) can significantly increase the plant height; the best effect is achieved when the paving thickness is 30cm. A pH value that is too low (6.5) or too high (8.0) has a negative impact on plant growth.

[0151] Plant growth ranged from 18g to 30g. Appropriate fertilizer ratios and neutral pH values ​​at similar plant heights promoted increased growth, with the highest growth at a paving thickness of 30cm.

[0152] ② The lead (Pb) content ranges from 100mg / kg to 160mg / kg. Adding organic fertilizer and appropriate fertilizer can effectively reduce the Pb content, and increasing the paving thickness can help further reduce it;

[0153] The cadmium (Cd) content ranges from 3.1mg / kg to 4.5mg / kg. Appropriate fertilizer ratio and neutral pH value can help reduce the Cd content. The paving thickness of 30cm is the best effect.

[0154] Mercury (Hg) content ranges from 1.2mg / kg to 2.3mg / kg. Adding organic fertilizer and appropriate fertilizer can reduce the Hg content. The best effect is achieved when the paving thickness is 30cm.

[0155] ③The pH value range of the experimental group was 6.4-7.8, and the pH value of the control group was 7.0. The neutral pH value (7.0) group performed best, and the extreme pH values ​​(6.5, 7.5, and 8.0) had different effects on some properties.

[0156] ④ Taking into account the plant height, growth, soil heavy metal content and pH value, the optimal ratio is 3.0% decomposed organic fertilizer, 1.1% superphosphate, 0.7% potassium magnesium sulfate fertilizer, paving thickness of 30cm, and pH value of 7.0. The optimal ratio is obtained through comprehensive analysis of the data in experimental groups 14, 16, and 20.

[0157] Experimental Examples 1 to 3 of the present invention, through systematic orthogonal experimental design and implementation, compared key factors including heavy metal content, pH value, unconfined compressive strength, internal friction angle, plant height, growth, etc.; verified the optimal ratio of the three-layer structure of the planting soil layer:

[0158] In the isolation layer, the moisture content of the original soil of the slope was 12.5%. The amount of the composite bacterial solution sprayed on the original soil of the slope per square meter was 0.75L of bacterial solution A and 1.5L of bacterial solution B.

[0159] In the slope protection skeleton, the mass percentage of each component in the silt is: 6.0% phosphogypsum, 7.5% fly ash, 5.0% manganese slag, and 8% cement;

[0160] In the slope surface layer, the mass percentage of each component in the silt is: 3.0% of decomposed organic fertilizer, 1.1% of superphosphate, 0.7% of potassium magnesium sulfate fertilizer, and the paving thickness is 30cm.

[0161] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A construction method for a vegetable slope structure using microorganisms and solid waste materials to improve silt soil, characterized in that: The following steps are involved: Laying the isolation layer: spray the composite bacterial solution containing heavy metal-degrading bacteria directly onto the surface of the original soil of the slope, and the bacterial solution infiltrates into the slope soil to form a biological heavy metal isolation layer; the heavy metal-degrading bacteria include Bacillus subtilis and Thiobacillus ferrooxidans; Casting slope protection skeleton: Mix silt, phosphogypsum, fly ash, manganese slag and cement in proportion and cast them on the isolation layer through the formwork to form the slope protection skeleton after solidification; Stacking slope surface layer: fill the silt compost planting soil and grass seeds into geotechnical ecological bags and fill them into the slope protection frame by artificial stacking. The silt compost planting soil is made by mixing silt with decomposed organic fertilizer, superphosphate and potassium magnesium sulfate fertilizer and then fermenting.

2. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: The silt is mixed with 5%-7% of phosphogypsum by mass, 6%-9% of fly ash, 4-6% of manganese slag and 8-10% of cement at an on-site mixing station for no less than 20 minutes. After being evenly mixed, it is cast using a frame beam type wooden formwork to form a slope protection skeleton; among them, the phosphogypsum particle diameter is ≤5mm, and the fly ash and manganese slag particle diameters are ≤3mm.

3. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: The silt compost planting soil is prepared by mixing silt with 2.5%-3.5% of decomposed organic fertilizer, 1%-1.2% of superphosphate and 0.5%-0.9% of potassium magnesium sulfate fertilizer and then stacking and fermenting.

4. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: In the isolation layer, the moisture content of the original soil of the slope is controlled to 12%-15%; the amount of composite bacterial liquid sprayed on the original soil of the slope is 2.1-2.55L / m 2 ; When preparing the composite bacterial solution, a 2% concentration of Bacillus subtilis bacterial solution and a 4% concentration of Thiobacillus ferrooxidans bacterial solution are prepared respectively, and then the two are mixed in a volume ratio of (2-3): (5-5.5) to obtain the composite bacterial solution.

5. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: The sludge in the slope protection framework and the slope surface layer is pond sludge. Before mixing the sludge, the water content of the sludge is reduced to 40%-50% by using a filter press, and then the dehydrated mud cake is spread in the dehydration area for drying until the sludge water content is reduced to 35%-40%. The daily processing capacity of the filter press is not less than 25m 3 ; The straight-line distance from the dewatering area to the sludge source shall not exceed 50m.

6. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: When the silt compost planting soil material is piled up for fermentation, the height of the pile shall not exceed 2m and the top of the pile shall be arc-shaped. During the fermentation process, the pile shall be turned over every 2-3 days to ensure that the temperature of the pile remains within the range of 45℃-65℃. The pile shall be piled up for no less than 7 days to ensure sufficient fermentation and eventually form granules with uniform structure, no odor and loose uniformity.

7. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: Make sure that the composite bacterial liquid spraying equipment is calibrated to ensure that the spraying amount per square meter is accurate; after spraying and maintenance, use the total station and GPS system to measure the slope in detail and build a slope frame beam type wooden formwork; record the slope height as H meters, when building the frame beam type wooden formwork, set positioning piles every 5 meters in the horizontal direction, set a horizontal support beam every H / 3 slope height in the vertical direction, add support rods every 2 meters vertically, and add corner wood reinforcement at the corners and edges.

8. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: After the construction of the slope surface layer is completed, a drainage ditch is set at the foot of the slope along the contour line, and a seepage pipe is set as needed to ensure the drainage function; the length of the slope foot is 2-4m; the width of the drainage ditch is 25-35cm, the depth is 15-25cm, and the slope is not less than 1%.

9. The construction method of a vegetable slope structure using microorganisms and solid waste materials to improve silt soil according to claim 1, characterized in that: In the isolation layer, the moisture content of the original soil of the slope is 12.5%. 0.75L of 2% Bacillus subtilis solution and 1.5L of 4% Thiobacillus ferrooxidans solution are sprayed on each square meter of the original soil of the slope. In the slope protection skeleton, the mass percentage of each component in the silt is: 6.0% phosphogypsum, 7.5% fly ash, 5.0% manganese slag, and 8% cement; In the slope surface layer, the mass percentage of each component in the silt is: 3.0% of decomposed organic fertilizer, 1.1% of superphosphate, 0.7% of potassium magnesium sulfate fertilizer, and the paving thickness is 30cm.

10. A vegetable slope structure for improving silt soil by using microorganisms and solid waste materials, characterized in that: The method for constructing a vegetable slope structure using microorganisms and solid waste materials to improve silt soil as claimed in any one of claims 1 to 9 comprises: The isolation layer is formed by spraying a composite bacterial solution on the original soil of the slope, and solidifying after the bacteria in the composite bacterial solution fully infiltrates into the soil; the composite bacterial solution contains Bacillus subtilis and Bacillus ferrooxidans; A slope protection frame, wherein the slope protection frame is arranged on the isolation layer and is constructed by casting with a frame beam type wooden formwork. The raw materials of the slope protection frame include silt and 5%-7% of phosphogypsum, 6%-9% of fly ash, 4-6% of manganese slag and 8-10% of cement, which accounts for 5%-7% of the weight of the silt; The slope surface layer is formed by stacking geo-ecological bags filled with silt compost and grass seeds. These geo-ecological bags are filled in layers into the slope protection frame that has been built, and 2-3 layers are laid as needed; in the silt compost, the percentage of each component in the silt mass is: 2.5%-3.5% of decomposed organic fertilizer, 1%-1.2% of superphosphate, and 0.5%-0.9% of potassium magnesium sulfate fertilizer.

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