A planting substrate and its method for ecological restoration of high-steep slopes

Abstract

The present invention discloses a vegetation substrate and a method for ecological restoration of high-steep slopes using the same. The vegetation substrate comprises the following components in parts by weight: 50 - 60 parts of water, 200 - 300 parts of peat soil, 10 - 20 parts of acrylic emulsion, 10 - 20 parts of lightweight aggregate, 60 - 80 parts of polyurethane emulsion, 1 - 2 parts of foaming agent, and 0.02 parts of grass seeds. The present invention has high compressive strength, can directly cover the slope surface, can effectively prevent the erosion and scouring of the slope surface by rainwater or running water, and improves the overall stability of the vegetation layer and the vegetation substrate; it has good fertilizer retention and water retention properties, can maintain the growth environment of plants for a long time, and is easy to maintain; at the same time, the present invention solves the problem of difficult construction of high-steep slopes of collapsible loess, forms an integrated structure, can protect and green the slope surface, and has the advantages of stability, regularity, rapidity, and beauty.

Description

Technical Field

[0001] The invention belongs to the technical field of vegetation planting, and in particular relates to a planting substrate and a method for using the substrate for ecological restoration of a high and steep slope. Background Art

[0002] With the rapid development of my country's economy, infrastructure construction has accelerated in various places. Civil engineering, transportation, water conservancy and hydropower, mining and other engineering construction require the excavation of a large number of slopes. Slope excavation destroys the original vegetation cover layer, forming a large number of secondary bare land, causing problems such as soil erosion and ecological imbalance. Geological disasters such as landslides and mud-rock flows occur from time to time. Slope protection has become the main engineering and technical means to solve the above problems. In addition, with people's increasing attention to the ecological environment, vegetation concrete with good ecological effects has come into being. Using vegetation concrete to protect slopes can not only consolidate and protect slopes, but also intercept rain and slow down flow through surface vegetation, purify the air, and beautify the environment.

[0003] The traditional vegetation concrete vegetation substrate has the following main problems: ① Poor permeability. Due to the particle size and pore structure of the soil itself, the permeability is poor, which seriously affects the water permeability of the vegetation concrete. ② Strong alkalinity. The alkaline environment of the porous soil in the filling layer cannot meet the needs of long-term plant growth. As time goes by, the pH value of the soil in the pores rises, forming an alkaline environment again, which is not conducive to plant growth, and even the plants wither and die due to alkali damage, which in turn affects the slope protection and greening effects. ③ Poor air permeability, the soil is easy to compact. The porous soil and surface soil inside the porous vegetation concrete are very easy to compact due to salinity, insufficient water retention and other reasons, which in turn affects the air permeability and causes the rot of plant roots.

[0004] CN108934911A discloses a coconut bran vegetation substrate and a preparation method thereof. The vegetation substrate comprises the following raw materials in the following mass percentages: 82%-90% coconut bran, 5%-15% soil, and 2%-3% organic fertilizer. The invention can significantly improve the water permeability of vegetation concrete after grass planting, and effectively improve the soil alkalinization environment caused by alkali precipitation of cement materials in vegetation concrete. However, the invention has a weak ability to resist erosion and scouring by rain or running water.

[0005] CN108496747A discloses a scour-resistant vegetation substrate, which includes the following components by weight: 60-70 parts of nutrient soil, 15-20 parts of organic fertilizer, 6-8 parts of glutinous rice mortar, 5-8 parts of straw and 1-2 parts of mineralized bacteria additives; the invention uses glutinous rice mortar as an early adhesive for the substrate to provide a strong early strength for the vegetation substrate and improve the early anti-scour ability of the substrate. However, the vegetation substrate of the invention has low strength and is only suitable for slope repair with a small slope, and has poor effect on collapsible loess slopes in western Henan.

[0006] There are a large number of high and steep slopes in our country (water conservancy and transportation construction sites, abandoned quarrying areas, urban high and steep spaces, abandoned mining areas), which need to be greened. Therefore, it is of great significance to develop a vegetative substrate suitable for the restoration of high and steep slopes in collapsible loess. Summary of the Invention

[0007] The purpose of the present invention is to provide a vegetative substrate and a method for ecological restoration of high and steep slopes using the same. The vegetative substrate has high strength, can directly cover high and steep (slope greater than 60°) slopes, prevent erosion and scouring of the slopes by rainwater or running water, and at the same time, has good fertilizer and water retention properties, can maintain the growth environment of plants for a long time, and is easy to maintain, providing technical support for the restoration of high and steep slopes in collapsible loess.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A vegetative substrate, comprising the following components in parts by weight: 50 - 60 parts of water, 200 - 300 parts of peat soil, 10 - 20 parts of acrylic emulsion, 10 - 20 parts of lightweight aggregate, 60 - 80 parts of polyurethane emulsion, 1 - 2 parts of foaming agent, and 0.02 parts of grass seeds.

[0010] Preferably, the lightweight aggregate is graded sand with a maximum particle size of 10 mm.

[0011] Preferably, the polyurethane emulsion meets the requirements of GB / T19520 - 2013.

[0012] Preferably, the foaming agent is sodium lauryl ether sulfate.

[0013] Preferably, the type of the grass seeds is tall fescue.

[0014] Preferably, the mass ratio of the acrylic emulsion, the polyurethane emulsion and the foaming agent is 10:70:1.5.

[0015] The present invention also provides a preparation method of the above vegetative substrate, mixing the formula amounts of peat soil, acrylic emulsion, lightweight aggregate, polyurethane emulsion, foaming agent and grass seeds with water to obtain the vegetative substrate.

[0016] The present invention also provides the application of the above vegetative substrate in the ecological restoration of high and steep slopes.

[0017] Preferably, the high and steep slope is a high and steep slope of collapsible loess with a slope greater than 60 degrees.

[0018] The present invention also provides an ecological restoration method for high and steep slopes of collapsible loess, comprising the following step: spraying the above vegetative substrate.

[0019] Preferably, the thickness of the spraying is 8 - 12 cm, and the spraying pressure is 0.1 - 0.3 MPa / s.

[0020] Further preferably, before spraying the vegetation substrate on the collapsible loess high-steep slope, wire mesh reinforcement treatment is adopted.

[0021] The beneficial effects of the present invention are as follows:

[0022] (1) The vegetation substrate of the present invention has high compressive strength, can directly cover the slope surface, can effectively prevent the erosion and scouring of the slope surface by rainwater or running water, and improve the overall stability of the vegetation layer and the vegetation substrate;

[0023] (2) The present invention has good fertilizer retention and water retention properties, can maintain the growth environment of plants for a long time, and is easy to maintain;

[0024] (3) The present invention solves the problem of difficult construction of collapsible loess high-steep slopes, forms an integrated structure, can protect and green the slope surface, and has the advantages of stability, regularity, rapidity, and beauty. Specific Embodiments

[0025] The following specific examples illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0026] Before further describing the specific embodiments of the present invention, it should be understood that the protection scope of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the embodiments of the present invention are for describing specific embodiments, rather than for limiting the protection scope of the present invention.

[0027] When the embodiments give a numerical range, it should be understood that unless otherwise specified in the present invention, any value between the two endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0028] The present invention does not limit the source of raw materials. Unless otherwise specified, the raw materials used are all ordinary commercially available products. The acrylic emulsion used in the present invention has a solid content of 35 ± 1%, a viscosity of 10 - 200 mPa·s, the polyurethane emulsion is a commercially available product that meets the requirements of GB / T19520 - 2013, the lightweight aggregate is graded sand with a maximum particle size of 10 mm, the foaming agent is sodium lauryl ether sulfate, the grass seeds are tall fescue, and the accelerating agent is sodium silicate.

[0029] Example 1

[0030] A vegetation substrate, comprising the following components in parts by weight: 50 parts of water, 300 parts of peat soil, 10 parts of acrylic emulsion, 15 parts of lightweight aggregate, 70 parts of polyurethane emulsion, 1.5 parts of foaming agent, and 0.02 parts of grass seeds.

[0031] The preparation method is to mix 300 parts of peat soil, 10 parts of acrylic emulsion, 15 parts of lightweight aggregate, 70 parts of polyurethane emulsion, 1.5 parts of foaming agent, and 0.02 parts of grass seeds with 50 parts of water for 30 s to obtain the vegetation substrate.

[0032] Example 2

[0033] A vegetation substrate, comprising the following components in parts by weight: 60 parts of water, 200 parts of peat soil, 20 parts of acrylic emulsion, 20 parts of lightweight aggregate, 60 parts of polyurethane emulsion, 2 parts of foaming agent, and 0.02 parts of grass seeds.

[0034] The preparation method is to mix 200 parts of peat soil, 20 parts of acrylic emulsion, 20 parts of lightweight aggregate, 60 parts of polyurethane emulsion, 2 parts of foaming agent, and 0.02 parts of grass seeds with 60 parts of water for 30 s to obtain the vegetation substrate.

[0035] Example 3

[0036] A vegetation substrate, comprising the following components in parts by weight: 50 parts of water, 250 parts of peat soil, 15 parts of acrylic emulsion, 10 parts of lightweight aggregate, 80 parts of polyurethane emulsion, 1 part of foaming agent, and 0.02 parts of grass seeds.

[0037] The preparation method is to mix 250 parts of peat soil, 15 parts of acrylic emulsion, 10 parts of lightweight aggregate, 80 parts of polyurethane emulsion, 1 part of foaming agent, and 0.02 parts of grass seeds with 50 parts of water for 30 s to obtain the vegetation substrate.

[0038] Comparative Example 1

[0039] The difference between this comparative example and Example 1 is that: the mass ratio of the acrylic emulsion, polyurethane emulsion and foaming agent is 10:80:2.5. Specifically, the vegetation substrate comprises the following components in parts by weight: 50 parts of water, 300 parts of peat soil, 10 parts of acrylic emulsion, 15 parts of lightweight aggregate, 80 parts of polyurethane emulsion, 2.5 parts of foaming agent, and 0.02 parts of grass seeds.

[0040] The preparation method is to mix 300 parts of peat soil, 10 parts of acrylic emulsion, 15 parts of lightweight aggregate, 80 parts of polyurethane emulsion, 2.5 parts of foaming agent, and 0.02 parts of grass seeds with 50 parts of water for 30 s to obtain the vegetation substrate.

[0041] Comparative Example 2

[0042] The vegetation substrate of this comparative example comprises the following components in parts by weight: 50 parts of water, 300 parts of peat soil, 10 parts of vermiculite, 30 parts of charcoal powder, 10 parts of acrylic emulsion, 10 parts of quick-setting agent, and 0.02 parts of grass seeds.

[0043] The preparation method is to mix the formula amounts of peat soil, vermiculite, charcoal powder, acrylic emulsion, quick-setting agent and grass seeds with water for 30 s to obtain the vegetation substrate.

[0044] Comparative Example 3

[0045] The vegetation substrate of this comparative example includes the following components in parts by weight: 50 parts of water, 300 parts of peat soil, 10 parts of acrylic emulsion, 15 parts of light aggregate, 10 parts of quick-setting agent and 0.02 parts of grass seeds.

[0046] The preparation method is to mix the formula amounts of peat soil, acrylic emulsion, light aggregate, quick-setting agent and grass seeds with water for 30 s to obtain the vegetation substrate.

[0047] The vegetation substrates prepared in Examples 1-3 and Comparative Examples 1-3 were sprayed onto a slope with a slope of 60° at a spraying pressure of 0.2 MPa / s and a spraying thickness of 10 cm, and the pH, water retention rate and seedling emergence situation of the vegetation substrates were investigated. The results are shown in Table 1.

[0048] Table 1 Statistical situation of different vegetation substrates

[0049] Group pH Water retention rate (%) Emergence rate (%) Example 1 6.8 16.8 95 Example 2 7 15.9 91 Example 3 7.5 16.2 90 Comparative Example 1 7.2 16.5 79 Comparative Example 2 8.2 13.4 78 Comparative Example 3 8.0 11.6 74

[0050] As can be seen from Table 1, the pH of the vegetation substrates prepared in Examples 1-3 of the present invention is 6.8-7.5, the water retention rate is 15.9-16.8%, and the seedling emergence rate is above 90%. The seedling emergence rate of the vegetation substrates prepared in Comparative Examples 1-3 is lower than 80%, indicating that the vegetation substrates prepared in Comparative Examples 1-3 are not suitable for plant growth and cannot be used for ecological restoration of slopes.

[0051] At 15°C and under the condition that the humidity is not less than 50%, the vegetation substrates prepared in Examples 1-3 and Comparative Examples 1-3 were sprayed to form a vegetation substrate with a length of 20 cm and a thickness of 10 cm. After 1 hour of formation, the compressive strength and permeability coefficient of different vegetation substrates were tested. The results are shown in Table 2.

[0052] Table 2 Statistical situation of the compressive strength and permeability coefficient of different vegetation substrates

[0053] Group Compressive strength Mpa <![CDATA[Permeability coefficient 10 -5 cm / s]]> Example 1 3.2 1.5 Example 2 2.4 1.8 Example 3 2.8 1.1 Comparative Example 1 1.7 2.3 Comparative Example 2 2.0 0.9 Comparative Example 3 1.5 0.7

[0054] As can be seen from Table 2, the vegetation substrates prepared in Examples 1-3 of the present invention have high compressive strength, can directly cover the slope surface, can effectively prevent the erosion and scouring of the slope surface by rainwater or running water, and improve the overall stability of the vegetation layer and the vegetation substrate. At the same time, the vegetation substrate has good permeability, solving the problem of poor water permeability of the vegetation substrate.

[0055] Specific embodiment: The project is located in Luoling Township, the seventh contract section of the Luoning section of the Zhengzhou-Lushi Expressway. It is located in the mountainous area. The mountain body is a mixed soil and rock slope surface. The soil is the surface sedimentary loess terrain, mixed with mudstone and slightly expansive soil. The slope gradient of this test section is 60°.

[0056] An ecological restoration method for collapsible loess high-steep slopes specifically includes the following steps:

[0057] (1) Cleaning the slope surface: Clean the loose floating stones and stone chip impurities on the surface layer of the slope surface. For the concave and cracked slope surfaces, manually fill them with plain soil until they are dense to make the slope surface basically flat.

[0058] (2) Spraying and wetting the reinforced surface: First, connect the galvanized iron wire mesh according to the slope length. Fix it with the main anchor bolts. The overlap between every two pieces of wire mesh is not less than 25 cm;

[0059] Drive all the main anchor bolts at the upper part of the slope surface. The main anchor bolts and the auxiliary anchor bolts are distributed at intervals. The spacing of the main anchor bolts is 100 cm, and the spacing of the auxiliary anchor bolts is 50 cm. The distribution between the main and auxiliary anchor bolts is in the pattern of plum blossom piles; For steep and smooth slope surfaces and places where the galvanized iron wire mesh cannot be closely attached to the slope surface, additional anchor bolts are installed to make the galvanized iron wire mesh closely attached to the slope surface;

[0060] The anchor nails are designed to meet the following requirements: The anchor nails are arranged in a plum blossom shape, with a spacing of 1000 mm × 1000 mm and a length of 300 - 500 mm. For the top of the slope, the more broken and severely weathered parts of the slope surface, the anchor nails are increased to Ф22 and the length is extended to 800 - 1000 mm. The exposed length of the anchor nails is 80 - 100 mm. They are tied to the galvanized wire mesh at a distance of 50 - 70 mm from the slope surface;

[0061] The drainage holes are designed to meet the following requirements: The spacing of the drainage holes is 3000 × 3000 mm, the hole diameter is not less than 30 mm, and the hole depth is 300 mm; When there is seepage on the slope surface, 10% - 20% more drainage holes need to be added and PVC pipes are installed.

[0062] (3) Wet spraying: Use compressed air or pressure water to blow all the surfaces to be sprayed clean, blow away the loose impurities or dust on the surfaces to be sprayed. The vegetation substrate (Example 1) is immediately sprayed after being mixed in the spraying machine; Ensure that the spraying speed is appropriate to facilitate the compaction of the vegetation substrate. The spraying pressure is 0.1 - 0.3 MPa / s.

[0063] (4) Maintenance: After spraying the vegetation substrate for 1 hour, spray water for maintenance. The maintenance time is not less than 7 days. Cover the non-woven fabric and fix it with U-shaped nails, bamboo strips, and 10-mm anchor bolts until the seedlings emerge; After the seedlings grow to 3 - 5 cm, uncover the non-woven fabric in stages for resistance training until it is completely uncovered.

Claims

1. A vegetation substrate, characterized in that, It consists of the following components in parts by weight: 50 - 60 parts of water, 200 - 300 parts of peat soil, 10 - 20 parts of acrylic emulsion, 10 - 20 parts of lightweight aggregate, 60 - 80 parts of polyurethane emulsion, 1 - 2 parts of foaming agent and 0.02 parts of grass seeds; The foaming agent is sodium lauryl polyoxyethylene ether sulfate; The solid content of the acrylic emulsion is 35 ± 1%, and the viscosity is 10 - 200 mPa·s; The mass ratio of the acrylic emulsion, polyurethane emulsion and foaming agent is 10:70:1.5; The grass seeds are tall fescue.

2. The vegetation substrate according to claim 1, characterized in that The lightweight aggregate is graded sand with a maximum particle size of 10 mm.

3. The vegetation substrate according to claim 1, characterized in that, The polyurethane emulsion meets the requirements of GB / T19520 - 2013.

4. A method for preparing the vegetation substrate according to any one of claims 1-3, characterized in that, Mix the peat soil, acrylic emulsion, lightweight aggregate, polyurethane emulsion, foaming agent and grass seeds in the formula amount with water to obtain the vegetative substrate.

5. Application of the vegetative substrate according to any one of claims 1 - 3 in the ecological restoration of high and steep slopes.

6. The application according to claim 5, wherein The high and steep slope is a high and steep slope of collapsible loess with a slope greater than 60 degrees.

7. An ecological restoration method for a collapsible loess high-steep slope, characterized in that, It includes the following steps: spraying the vegetative substrate according to any one of claims 1 - 3.

8. The ecological restoration method according to claim 7, wherein The thickness of the spraying is 8 - 12 cm.