Features: Geotextile mat turf slope protection has the advantages of low cost, convenient construction, vegetation restoration and environment beautification.
Disadvantages: At present, most geotextile mats are made of thermoplastic resin, which is easy to form secondary pollution in the soil after aging.
Planting grass for slope protection in geocell;
Slope protection by planting grass in geocell: it refers to a slope protection technology in which improved foreign soil is filled in a fixed geocell on a slope, and then a three-dimensional vegetation net is hung on the geocell for spray seeding construction. Using geocell to provide a stable and good living environment for lawn growth.
Features: Using geocell to plant grass can make the slope of barren land fully green, and the format with holes can also improve the drainage performance of the slope. Suitable for mudstone, limestone, sandstone and other gently sloping rock cutting slopes.
Disadvantages: A slower slope is required.
Honeycomb grid planting grass for slope protection;
Honeycomb grid planting grass slope protection is a slope protection technology similar to dry paving flaky slope protection. It is a slope protection measure that regular hexagonal concrete frame bricks are laid on the trimmed slope to form a honeycomb grid, which is filled with planting soil, and then grass or grass is planted in the brick frame.
Features: The frame bricks used in this technology can be mass-produced in the prefabrication yard, and the stress structure is reasonable. Slope pavement can effectively disperse rainwater runoff, slow down water flow, prevent slope erosion and protect turf growth. This kind of slope protection is simple in construction, neat in appearance and elegant in shape, and has the dual effects of slope protection and greening.
Disadvantages: The cost is higher than that of mortar rubble frame slope protection, which is mostly used for filling slope protection, and the overall soil consolidation effect is not very good because the concrete frame brick separates grass from grass.
Gabion slope protection:
Gabion slope protection is an engineering protective structure with high galvanized steel wire or hot-dip galvanized aluminum-zinc alloy steel wire as the main material and filled with non-weathered fillers such as stone.
Features: Good flexibility, water permeability, durability and wave resistance, and good ecology. Its structure can be fine-tuned through its own adaptability, and settlement cracks will not occur due to uneven settlement, and the overall structure will not be damaged. Because of the large gap in the gabion, the gabion can be covered with soil or filled with the gap. After a long period of processing, microorganisms and various organisms form soft and nutritious topsoil, which realizes the natural circulation of perennial herbs.
Mainly used for slope protection of rivers and bank slopes. It can not only prevent the river bank from being damaged by current and wind waves, but also maintain the natural convection exchange function between water and soil under the slope and realize ecological balance; It not only protects the embankment slope, but also increases the green landscape.
Disadvantages: exposed grid, metal corrosion, aging of plastic grid, alloy properties, etc. And the exposed grid is easy to be damaged locally, and the loose stones in the grid are easy to fall out of the grid, which is an important factor affecting the safety of this kind of retaining wall. In addition, the cutting ends of metal and alloy grids are very sharp, and people who are hydrophilic and climb to save themselves are easily hurt.
Vegetation belt (bag) slope protection:
Planting belt is to attach non-woven fabric containing seeds and fertilizers to a special PVC net bag, and then fill the bag with planting soil, which is matched according to the shape of the mountain to realize greening.
Features: The matrix of this method is not easy to be lost, and it can be piled into any shape suitable for slope, and the construction is simple. It is suitable for emergency projects such as vertical or nearly vertical rock surface or hard ground, landslide and collapse, and can also be used as mountain horizontal line and drainage ditch (instead of stone drainage ditch).
Disadvantages: large-scale use, high cost, slow plant growth, need to support grass seed spraying technology, in order to achieve greening effect as soon as possible.
Vegetation substrate plant slope protection:
Vegetation slope protection is a kind of construction technology, which uses the special jet device of helicopter to spray the mixture of helicopter materials and rainwater on the stable slope after installing anchor rods and hanging nets. Plants grow and develop on the basis of vegetation-based materials, which have dual functions of slope protection and vegetation restoration, and can replace traditional measures such as shotcrete and anchor support and masonry slope protection. Its basic structure consists of three parts: anchor rod (nail), net and plant substrate.
Features: It solves the construction technical effect that ordinary greening can't achieve; Not limited by geological conditions.
Disadvantages: the construction technology is relatively difficult and the engineering quantity is large; The substrate sprayed by the sun is thin and easy to "crack" and fall off after exposure to the sun; If the substrate material of spray seeding is thick and heavy, the hanging net is easy to fall off; The project cost is high and the investment is large.
Filling frame and planting grass for slope protection:
Filling vegetation in the frame for slope protection refers to first building a frame with prefabricated frames or concrete on the slope, and then planting green plants in the soil built in the frame. In order to fix exotic soil, it can be used in combination with geocell grass planting slope protection, three-dimensional vegetation net slope protection, mortar rubble skeleton grass planting slope protection, honeycomb grid grass planting slope protection and so on. This method has high cost and is generally only used for high-steep rock slopes and barren soil slopes with poor shallow stability and difficult greening.
Vetiver grass technology:
Vetiveria zizanioides technology refers to the comprehensive application technology that vetiveria zizanioides is mixed with other auxiliary grasses with relatively developed roots, planted according to the correct planning and design, and quickly formed high-density aboveground hedgerows and underground high-strength biological walls after about 60 days of professional maintenance and management. It is referred to as "VGT" (Vetiveria zizanioides technology) scheme at home and abroad, which is suitable for slopes with unstable soil or broken rock strata. The slope is between 200 and 700, and the topsoil is prone to gully erosion and shallow landslides and landslides. For example, high and steep slopes formed by excavation or filling in mountainous and hilly areas.
The main raw materials of Vetiveria zizanioides technology are Vetiveria zizanioides, Bahia grass, Bermuda grass, soil improver, special fertilizer for Vetiveria zizanioides and so on.
Features: Developed root system, high strength, tensile and shear strength of 75MPa and 25MPa respectively, which can prevent shallow landslides and landslides; Fast growth, intercepting 98% of sediment; Strong anti-flooding ability (completely submerged 120 days will not die), strong soil consolidation and water retention, strong anti-erosion ability; Leaf transpiration is large, which can eliminate saturated water in soil as soon as possible; The characteristics of asexual reproduction are that weeds are not formed; Construction is not affected by seasons; The project cost is moderate, which is lower than that of traditional masonry. The results showed that the tensile strength of Vetiveria zizanioides root system was large, which increased linearly with the number of roots (aggregation degree) and decreased slightly with the length of roots. The physical and mechanical properties of sandy clay mixed with vetiver roots have changed significantly, that is, the bulk density of soil has decreased, while the shear strength has increased obviously. Its roots are deep, long and dense, up to 5 meters long, and its tensile strength is high. Rows of vetiver grass can stabilize the slope and control flood erosion like rows of steel bars, which is equivalent to concrete slope protection, but its cost is only one tenth of that of concrete slope protection.
Disadvantages: the ground hedge is high and lacks the landscape effect of the lawn; Not tolerant of shade, not interplanting with trees; Only suitable for the area south of the Yellow River.
Note: Vetiveria zizanioides ecological engineering has obvious slope protection effect. After half a year, it can produce obvious slope protection effect. After four years, the biodiversity is greatly increased, the soil moisture and nutrient content are improved in different degrees, the ecological environment of the slope is obviously improved, and a lot of engineering funds can be saved. It is suggested that other technologies can be combined according to the construction site, and the effect will be better, and it can also play the role of fostering strengths and avoiding weaknesses.
Reinforced fiber blanket:
The reinforced fiber blanket is a multi-layer structure composed of fiber materials such as coconut fiber, water-retaining agent, plant species, peat and slow-release fertilizer, and upper and lower PP or PE nets, and its thickness is about 4-8 cm. It is mainly used for water and soil protection of mountain rock slopes, highways, railway slopes and other slopes.
Features: The reinforced fiber blanket is laid on the slope and then fixed. Because the soil surface is covered with coconut blanket, the erosion of rain on the soil will be greatly reduced. This product provides an ideal growth environment for plant roots (heat preservation, more conducive to water absorption, prevention of surface erosion, balanced seed germination rate, etc.). ), promote the good growth of plants under unfavorable conditions, so as to achieve the effect of plant greening and preventing soil erosion. When a hardened fiber blanket is used, it does not need to be removed. On the one hand, coconut blanket can grow plants, on the other hand, it can be degraded into organic fertilizer needed for plant growth, which is very environmentally friendly.