CN111802214A

CN111802214A - Greening structure soil, root-blocking structure containing greening structure soil and construction method of root-blocking structure

Info

Publication number: CN111802214A
Application number: CN202010767796.9A
Authority: CN
Inventors: 陈质毅; 封伟; 王贺; 王昂; 白学永
Original assignee: China Construction Second Engineering Bureau Co Ltd
Current assignee: China Construction Second Engineering Bureau Co Ltd
Priority date: 2020-08-03
Filing date: 2020-08-03
Publication date: 2020-10-23

Abstract

The invention discloses greening structure soil, a root-resisting structure containing the same and a construction method thereof, wherein the greening structure soil comprises the following components: 100 units of dry weight of stone aggregate, 20-25 units of clay loam, 0.035 units of binder, 6.6-8 units of water. The tree growth stopping structure comprises a foundation layer, backfill soil, a water filter pipe, geotextile laid on the water filter pipe, a tree pit opening, tree balls arranged in the tree pit opening, a root stopping area arranged around the tree pit opening, greening structure soil filled in the root stopping area and a soil covering finishing surface layer. The greening structural soil can meet the requirement of road bearing capacity, the large gap of the greening structural soil can meet the growth of plant roots, and the greening structural soil can be widely applied to hard ground such as pedestrian pavement and landscape road pavement and has good ecological benefits.

Description

Greening structure soil, root-blocking structure containing greening structure soil and construction method of root-blocking structure

Technical Field

The invention relates to the field of ground construction, in particular to greening structural soil, a root-resisting structure containing the same and a construction method thereof.

Background

Urban greening is the activity of growing plants to improve the urban environment. Urban landscaping, which is a reduction organization in an urban ecosystem, has the ability to restore the original state after being disturbed and destroyed by external factors, which is known as the reduction function of the urban ecosystem. The greening engineering must be carried out by a case approved greening engineering design and related construction documents.

At present, in landscape architecture construction, greening planting and hard landscape are combined more and more tightly. Under the background of urban modernization, the green space gradually shrinks, and the plant root system often grows to intersect with the road pavement position.

Because the common planting soil is not compacted too densely, the soil compacted degree under hard pavement is not required to be settled easily, and if the planting soil is compacted too densely, the development and growth of plant roots are influenced.

Disclosure of Invention

The invention aims to provide greening structural soil, a root-blocking structure containing the same and a construction method thereof, and aims to solve the technical problems that the bearing of an adjacent road has great damage to the development of plant roots, the opposite surface layer is damaged in the development process of the plant roots, the pavement is carried out by people, and the pavement effect of landscape roads is poor.

In order to achieve the purpose, the invention adopts the following technical scheme: the invention provides a greening structural soil, which comprises the following components: 100 units of dry weight of stone aggregate, 20-25 units of clay loam, 0.035 units of binder, 6.6-8 units of water.

Further, the stone aggregate is granite; the particle size of the stone aggregate is 40-75 mm.

Further, the adhesive is polypropylene adhesive. (PAM)

Further, the proportion of each component of the structural soil is that macadam, clay, water and a soil tackifier = 10: 2.5: 0. 004: 1.5.

further, the water is drinkable fresh water or regenerated water.

The invention also provides a tree life-stopping structure containing greening structure soil, which comprises a foundation ground base layer 1, backfill soil 2, a water filter pipe, geotextile laid on the water filter pipe, a tree pit opening 3, a tree ball 4 arranged in the tree pit opening 3, a root-stopping area 5 arranged around the tree pit opening 3, greening structure soil filled in the root-stopping area 5, an earth covering finishing surface layer 6 and a tree pit cover plate erected on the earth covering finishing surface layer 6, wherein the water filter pipe comprises a vertical pipe 7 and a coil pipe 8, the top of the vertical pipe 7 is lower than the top of the earth covering finishing surface layer 6, the bottom of the vertical pipe 7 is communicated with the coil pipe 8, the coil pipe 8 is arranged at the bottom of the tree pit opening 3, and the coil pipe 8 is provided with a water outlet which is communicated with a municipal drainage pipe; backfill 2 is arranged between the bottom of the coil pipe 8 and the foundation stratum basale 1, and the backfill 2 is arranged around the root blocking area 5. Furthermore, the cross section of the root resistance area is circular, and the radius of the root resistance area is 1500 mm.

The invention also provides a construction method of the tree ecological blocking structure, which comprises the following specific steps:

step one, preparing a structural soil material for greening; mixing broken stone, clay, water, soil tackifier and the like according to different proportions;

step two, stirring the mixture of the greening structural soil; mixing the greening structure soil on the pavement surface in the mixing facility by using a forklift or similar equipment in proportion to mix the greening structure soil, so that the greening structure soil cannot be stirred on site; adding water when the forklift falls and at the same time, and stirring all the materials until a certain mixing degree is reached; the water content is kept fully and stably all the time, and the water content is measured and monitored in the stirring process and after the stirring is finished.

Step three, preparing on site;

cleaning the on-site planting pond before backfilling the greening structural soil, so that pollutants cannot be contained; the method protects the adjacent road or structure and prevents the pollution caused by the soil filling work; for the greening structure soil in the paving area, laying filter pipes, keeping the positions of arbor tree balls by adopting a round steel mould before backfilling operation, and erecting a common planting pool by adopting a template.

Backfilling, namely laying greening structural soil in layers, and laying thick ramming; paving greening structural soil and pipelines for cross construction; and a measure of covering geotextile is carried out on a greening structure soil area or planting soil area which does not need to be planted immediately, so that pollution is prevented.

And fifthly, planting, namely planting the seedlings according to the positions of the remained soil balls after the greening structure soil is paved, backfilling common planting soil to the gaps after planting, and compacting.

Furthermore, in the first step, the particle size of the crushed stone is larger than 50mm, and the proportion of the crushed stone is not more than 70%.

Furthermore, in the second step, after the stirring is completed, the plastic cloth must be loaded and covered as soon as possible and then transported to the field for use.

Further, in the third step, the circular steel film is larger than the soil ball with the outer diameter of 300 mm.

Further, in the fourth step, each layer is 200-250mm when the greening structure soil is paved in layers.

Further, in the fifth step, the compaction degree of the greening structural soil is 95%.

The invention has the beneficial effects that:

the greening structural soil, the root-blocking structure containing the greening structural soil and the construction method thereof adopt the greening structural soil, can meet the requirement of road bearing capacity, have larger gaps and can meet the growth of plant roots, and the greening structural soil can be widely used for hard ground such as pedestrian pavement, landscape road pavement and the like and has good ecological benefit.

The greening structure soil, the root-blocking structure containing the greening structure soil and the construction method thereof are characterized in that the greening structure soil is formed by manually mixing broken stones with certain particle sizes, clay, water, a soil tackifier and the like according to a proportion, can meet the strength requirement of paving concrete, asphalt and surface layer materials, and has large pores necessary for plant root growth and air exchange. Meanwhile, in the process of plant growth and root system development, the damage of the root system to the surface layer can be avoided due to the internal space characteristic of the structural soil.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The primary objects and other advantages of the invention may be realized and attained by the instrumentalities particularly pointed out in the specification.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a first embodiment of the present invention.

Fig. 2 is a top view of a tree stopping structure.

Reference numerals: 1-foundation ground layer, 2-backfill, 3-hole opening of tree pits, 4-tree balls, 5-root blocking area, 6-soil covering finishing surface layer, 7-vertical pipe and 8-coil pipe.

Detailed Description

The technical solutions of the present invention are described in detail below by examples, and the following examples are only exemplary and can be used only for explaining and illustrating the technical solutions of the present invention, but not construed as limiting the technical solutions of the present invention.

Examples

This embodiment is applied to a certain theme park mark section two, and about 4.8 ten thousand m of outdoor greening area is mainly used for planting the pond and is close to road one side region and stereoplasm region of mating formation, and afforestation structure soil is formed by rubble, clay, water, soil tackifier etc. of certain particle diameter according to the proportion manual mixing, and it can reach the intensity requirement that concrete, pitch, surface course material were laid, and possesses the necessary macroporosity of satisfying plant roots growth and air exchange. Meanwhile, in the process of plant growth and root system development, the damage of the root system to the surface layer can be avoided due to the internal space characteristic of the structural soil.

1. Preparation of structural soil material for greening

Broken stone, clay, water, soil tackifier and the like are proportioned according to different proportions.

It is noted that, first, at least 30 days before the material order, the certification test to be performed on the soil, gravel/rock samples, certificates, manufacturer documents and the specified materials is submitted, and the samples are labeled with the source of the material, the date of sampling and the name of the project; submitting all soil source fields or source fields.

And secondly, after the soil and the rocks to be adopted pass the examination, mixing to prepare structural and discontinuous graded soil. Representative structural soil mixture samples of 10 liters were submitted for testing, analysis and approval. The entire site or stockyard may be sampled randomly and all samples submitted to a testing laboratory.

Third, the test analysis report for each soil sample was submitted to a soil testing laboratory.

Fourth, gravel and rock testing provides particle size analysis including the following mineral content gradient, USDA particle size in millimeters 80mm, 65-76mm, 50-65mm, 37-50mm, 25-37mm, 19-25m, fine gravel 2-19mm, sand 0.05-2mm, silt-0.002-0.05 mm, clay-0.002 mm.

2. Stirring structural soil mixture

Mixing the greening structure soil on the pavement surface in the mixing facility by using a forklift or similar equipment in proportion to mix the greening structure soil, so that the greening structure soil cannot be stirred on site; adding water when the forklift falls and at the same time, and stirring all the materials until a certain mixing degree is reached; the water content is kept fully and stably all the time, and the water content is measured and monitored in the stirring process and after the stirring is finished.

3. On-site preparation

Cleaning the on-site planting pond before backfilling the greening structural soil, so that pollutants cannot be contained; the method protects the adjacent road or structure and prevents the pollution caused by the soil filling work; for the greening structure soil in the paving area, laying filter pipes, keeping the positions of arbor tree balls 4 by adopting a round steel mould before backfilling operation, and erecting a common planting pool by adopting a template.

4. Backfilling operation

Laying greening structural soil in layers, wherein each layer is not more than 250mm, and laying the soil thickly and tamping the soil; paving greening structural soil and pipelines for cross construction; and a measure of covering geotextile is carried out on a greening structure soil area or planting soil area which does not need to be planted immediately, so that pollution is prevented.

5. Planting

After the greening structure soil is paved, seedling planting is carried out according to the positions of the remained soil balls, and after the planting is finished, common planting soil is backfilled in the gaps.

Fifthly, main technical characteristics, parameters and indexes

The greening structure soil mainly comprises broken stones, clay, water and a soil tackifier in a proportion of 10: 2.5: 0.004: 1.5; controlling the particle size of the broken stone aggregate to be 40-75 mm; the paving thickness of each layer of the greening structural soil is 200-250 mm; the size of the steel die is 300mm of the edge of the soil ball; the compaction degree of the greening structure soil is 95 percent; the water content is 6.6% -8%; construction is forbidden in rainy season, and the stacking position of the greening structure soil is covered by three-prevention cloth.

Wherein, A is determined according to the result of mechanical analysis, the soil is sand or loam of a CMA classification system, has uniform components and does not contain a bottom soil additive. The soil should not contain stones greater than 12 mm, plants and their roots, debris and other foreign matter greater than 25 mm in diameter, or pieces of the same kind as determined by the owner. The soil should not contain toxic substances that would be detrimental to plant growth. The soil must be obtained from areas with good natural drainage, and the surface soil of the areas is never stripped off, so that the vegetation growth condition is satisfactory. The soil should contain 3% to 7% organic matter determined by the organic carbon and total nitrogen content of the oven dried sample.

Mechanical analysis of the soil B was as follows: 1. texture: based on material passing through a 2mm sieve; 2. gravel: less than 5%. 3. Sand: 20 to 50 percent. 4. Silt: 20 to 30 percent. 5. Clay: 25 to 60 percent. C. The chemical analysis should meet or be modified to meet the following criteria: 1 pH value: 6.5 to 7.6; 2, organic matter content: 3-7% of dry weight. 3, the test laboratory recommends the content of nutrient elements required by the soil growth plant type; D. fertility: the concentration range of the essential elements in the soil meets the following specifications. The soil may need to be fertilized for optimal fertility: the effective phosphorus Pmg/kg-is more than or equal to 20; the effective potassium is Kmg/kg-130; available sulfur Smg/kg-20-500; effective magnesium Mgmg/kg-50-280; the effective calcium is Camg/kg-200-; femg/kg-4 to 350 of effective iron; effective manganese Mnmg/kg-0.6-25; effective molybdenum M.mg/kg-0.04-2; cumg/kg-0.3-8 of effective copper; effective zinc Znmg/kg-1-10.

Toxic elements and compounds and excess nutrient elements are below UC guidelines and soil testing laboratory regulations. The maximum element concentration allowed in the soil must not exceed the following concentrations: total cadmium is less than or equal to-0.6, total mercury is less than or equal to-1, total lead is less than or equal to-300, total chromium is less than or equal to-200, total arsenic is less than or equal to-30, total nickel is less than or equal to-80, total copper is less than or equal to-300, and total zinc is less than or equal to-350.

a. Soluble salt: the saturated extract has a concentration of less than 3.0 milli-ohms per centimeter.

b. Shed: the content of the saturated extract is less than one millionth.

c. Uranium adsorption ratio: less than 4.

d. Carbon-nitrogen ratio: less than 15: 1.

e. the soil should be the product of a commercial processing facility that is specifically manufactured to strip natural topsoil or other sources of topsoil.

Fertilizer: 1, improvement: providing fertilizer and/or other improvements as needed based on soil test results and recommendations. The analysis was performed according to the requirements suggested by soil testing. 2, the commercial fertilizer slow release type complies with the fertilizer management law of the people's republic of China. Fertilizer is delivered in unopened containers, accompanied by manufacturer certification, including the analysis that should be provided to the owner. Sulfur: commercial grade granules, 96% pure. Calcium carbonate lime: agricultural dolomite limestone containing at least 50% calcium carbonate, 25% carbonate and 11% inorganic carbon, 100% passing through a 10 mesh screen.

Gravel/rock, which is a narrow graded crushed granite, does not contain limestone or sandstone, is angular or triangular, and has a nominal particle size of 40-75 mm. Any two optional dimensions of acceptable aggregates do not exceed 1.5: 1.0.

gypsum, agricultural minerals containing at least 92% calcium sulfate dihydrate. Minimum grading: 100% pass through a 10 mesh screen: 98 percent of the powder passes through a 20-mesh sieve, 60 percent of the powder passes through a 60-mesh sieve, and 40 percent of the powder passes through a 100-mesh sieve.

Soil binder polypropylene cool-limb PAM, soil binder I: the acrylic acid-acrylic acid cool glue gel copolymer has the pH value of 6.5 to 7.0, is non-toxic and water-soluble, and is specially prepared for mixed structural soil planting backfill. PAM-C. mpleteGreenC. Linear water soluble acrylate gellan copolymer S from mpany.

The structural soil, gravel/rock and polypropylene treated soil are mixed uniformly according to the following proportion. According to the recommendations of the test laboratory, the soil should be treated beforehand with polypropylene crusts. The initial mix ratio of the test should be determined by adjusting the gravel/rock and soil ratio to ensure that the volume percent of soil in the mixture is 20% to 50% of the gravel pack porosity, which is determined by gravel pack basis weight and soil bulk weight or by compositional separation.

As shown in fig. 1 and 2, the root-blocking structure comprises a foundation ground layer 1, backfill soil 2, a water filter pipe, geotextile laid on the water filter pipe, a tree pit opening 3, a tree ball 4 arranged in the tree pit opening 3, a root-blocking area 5 arranged around the tree pit opening 3, greening structure soil filled in the root-blocking area 5, an earth covering finishing surface layer 6 and a tree pit cover plate erected on the earth covering finishing surface layer 6, wherein the water filter pipe comprises a vertical pipe 7 and a coil pipe 8, the top of the vertical pipe 7 is lower than the top of the earth covering finishing surface layer 6, the bottom of the vertical pipe 7 is communicated with the coil pipe 8, the coil pipe 8 is arranged at the bottom of the tree pit opening 3, and the coil pipe 8 is provided with a water outlet communicated with a municipal drainage pipe; backfill 2 is arranged between the bottom of the coil pipe 8 and the foundation stratum basale 1, and the backfill 2 is arranged around the root blocking area 5. The cross section of the root resistance area is circular, and the radius of the root resistance area is 1500 mm.

The construction method of the tree ecological stopping structure comprises the following specific steps:

step one, preparing a structural soil material for greening; mixing broken stone, clay, water, soil tackifier and the like according to different proportions; the particle size of the crushed stone is larger than 50mm, and the proportion of the crushed stone is not more than 70%.

Step two, stirring the mixture of the greening structural soil; mixing the greening structure soil on the pavement surface in the mixing facility by using a forklift or similar equipment in proportion to mix the greening structure soil, so that the greening structure soil cannot be stirred on site; adding water when the forklift falls and at the same time, and stirring all the materials until a certain mixing degree is reached; the water content is kept fully and stably all the time, and the water content is measured and monitored in the stirring process and after the stirring is finished. After the stirring is completed, the plastic cloth must be loaded and covered as soon as possible and transported to the field for use.

Step three, preparing on site;

removing the existing soil to the elevation of the finished surface, subtracting the discontinuous grading soil depth, and cleaning the field planting pool before backfilling the greening structural soil without containing pollutants; the method protects the adjacent road or structure and prevents the pollution caused by the soil filling work; for the greening structure soil in the paving area, laying filter pipes, keeping the positions of arbor tree balls 4 by adopting a round steel mould before backfilling operation, and erecting a common planting pool by adopting a template. The circular steel film is larger than the soil ball with the outer diameter of 300 mm.

Backfilling, namely laying greening structural soil in layers, and laying thick ramming; paving greening structural soil and pipelines for cross construction; and a measure of covering geotextile is carried out on a greening structure soil area or planting soil area which does not need to be planted immediately, so that pollution is prevented. Each layer is 200-250mm when the greening structure soil is paved in layers. The greening structure soil is installed in layers, each layer is 150 mm and 6 inches, and each layer is tamped after being installed. If the upper layer cannot be constructed immediately, the covering protection work is needed, and the water is particularly kept to prevent the structural soil from being dried.

And fifthly, planting, namely planting the seedlings according to the positions of the remained soil balls after the greening structure soil is paved, backfilling common planting soil to the gaps after planting, and compacting. The compaction degree of the greening structure soil is 95%. And adjusting the filling soil to the finish surface shown in the drawing. Immediately, the installed fill is provided with protection against excessive sun exposure or construction debris, water, or other potential changes in the particle size distribution in the mix.

During construction:

1, field inspection, wherein the field must be inspected before construction, and the construction conditions are ensured to be met on the field: the site meets the requirements, mechanical equipment and tools are provided, personnel training is qualified, and temporary unloading points are arranged on the site.

2, installation work must not be started until the adjacent walls, curbs, footings and public works are completed or approved by the employer. And (4) suspending the site element construction taking the greening structure soil as the foundation support, and immediately continuing the related construction or coverage protection work after the greening structure soil installation work is finished.

And 3, confirming that the surface and the foundation are properly leveled and tamped.

If the subsurface conditions affect the completion or adversely affect backfill moisture, the employer must be notified.

And 5, removing all debris, garbage, rubbles and other foreign matters in the foundation pit. If fuel, engine oil, concrete wash mud, or other hazardous materials spill out, they should be excavated sufficiently to remove them. The overbreak is filled with approved filler and tamped to the desired degree of foundation compaction.

And 6, protecting adjacent walls, roads and public facilities from damage caused by filling work.

The material delivered for installation is checked periodically to ensure consistency between the material and approved samples 7. If there is a significant difference between the installed material and the approved sample, the supplier is asked to test the installed fill. Based on the results of the employer approval test, if any fill required for testing differs significantly from the results of the employer approval test, removal and reinstallation of fill meeting the regulatory requirements is undertaken.

The invention provides a method for planting greening structural soil with a root-blocking structure, which comprises the steps of proportioning, stirring, backfilling, steel molding, wood molding and arbor planting, and aims to solve the problems that the traditional common planting soil is not compacted densely, the soil compacted under hard pavement cannot meet the requirement for settlement, and if compacted densely, the development and growth of plant roots are influenced. Therefore, the root-blocking structural soil can meet the requirement of road bearing capacity, the large gap of the greening structural soil can meet the growth of plant roots, and the greening structural soil can be widely used for hard ground surfaces such as pedestrian pavement and landscape road pavement and has good ecological benefits.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that may be made by those skilled in the art within the technical scope of the present invention will be covered by the scope of the present invention.

Claims

1. Greening structure soil, its characterized in that: comprises the following components: 100 units of dry weight of stone aggregate, 20-25 units of clay loam, 0.035 units of binder, 6.6-8 units of water.

2. A green structural soil as claimed in claim 1, wherein the stone aggregate is granite; the particle size of the stone aggregate is 40-75 mm.

3. A green structural soil as claimed in claim 1, wherein the adhesive is polypropylene.

4. The greening structural soil of claim 1, wherein the proportion of each component of the structural soil is stone aggregate, clay loam, water, tackifier = 10: 2.5: 0.004: 1.5.

5. a green structural soil as claimed in claim 1, wherein the water is drinkable fresh water or reclaimed water.

6. A tree stopping structure containing the greening structural soil of any one of claims 1 to 5, comprising a foundation base layer (1), backfill soil (2), a strainer, geotextiles laid on the strainer, and a tree pit opening (3), the tree planting device comprises tree balls (4) arranged in tree pit openings (3), a root blocking area (5) arranged around the tree pit openings (3), greening structure soil filled in the root blocking area (5), an earthing completion surface layer (6) and a tree pond cover plate erected on the earthing completion surface layer (6), a water filter pipe comprises a vertical pipe (7) and a coil pipe (8), the top of the vertical pipe (7) is lower than the top surface of the earthing completion surface layer (6), the bottom of the vertical pipe (7) is communicated with the coil pipe (8), the coil pipe (8) is arranged at the bottom of the tree pit openings (3), the coil pipe (8) is provided with a water outlet, and the water outlet is communicated with a municipal drainage pipe; backfill (2) is arranged between the bottom of the coil pipe (8) and the foundation (1), and the backfill (2) is arranged around the root resistance area (5).

7. A tree stopping structure as defined in claim 6, characterised in that the root stopping zone (5) is circular in cross-section, the radius of the root stopping zone (5) being 1500 mm.

8. The construction method of the tree growth-stopping structure according to claim 6 or 7, comprising the following specific steps:

firstly, preparing a greening structural soil material; mixing broken stone, clay, water, soil tackifier and the like according to different proportions;

step two, stirring the mixture of the greening structural soil; mixing the greening structure soil on the pavement surface in the mixing facility by using a forklift or similar equipment in proportion to mix the greening structure soil, so that the greening structure soil cannot be stirred on site; adding water when the forklift falls and at the same time, and stirring all the materials until a certain mixing degree is reached; the water content is kept fully and stably all the time, and the water content is measured and monitored during and after the stirring process;

step three, preparing on site;

cleaning the on-site planting pond before backfilling the greening structural soil, so that pollutants cannot be contained; the method protects the adjacent road or structure and prevents the pollution caused by the soil filling work; laying filter pipes for greening structural soil in a paving area, keeping the positions of arbor tree balls (4) by using a round steel mould before backfilling operation, and erecting a planting pool by using a template;

backfilling, namely laying greening structural soil in layers, and laying thick ramming; paving greening structural soil and pipelines for cross construction; a step of covering a greening structure soil area or planting soil area which does not need to be planted immediately with geotextile to prevent pollution;

and fifthly, planting, namely planting the seedlings according to the positions of the remained soil balls after the greening structure soil is paved, backfilling common planting soil and backfilling soil (2) to the gaps after planting, and compacting.

9. The construction method according to claim 8, wherein in the third step, the circular steel film is larger than the soil ball by 300mm in outer diameter.

10. The construction method according to claim 8, wherein in the fourth step, each layer is 200-250mm when the greening structural soil is layered.