JP4623576B2 - Slope structure and its construction method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a slope spray composition that can be stably fixed on a slope, a slope structure in which a slope spray humus soil layer is laminated on the slope spray solidified layer, and a construction method thereof.

The conventional slope structure is formed by applying mortar to the slope, spraying ordinary soil before the mortar hardens, and then spraying plant seeds together with bark compost etc. The Moreover, the construction method which apply | coats mortar to a slope, arrange | positions a palm mesh on it, and suppresses the fluidization of a slope surface soil and spray material is generally used (patent document 1).
However, even though these methods are considered for vegetation formation, no consideration is given to maintenance after vegetation formation.
For example, the material used for the slope structure is made of mortar, soil, natural plant fiber, etc., so that the plant seeds sprayed with compost will have roots that grow with the growth, and the material will grow over time. May be destroyed.
In addition, the planted lawn and the like need to be maintained and managed to be trimmed to a certain height by human hands, but it is a dangerous operation when cutting on a slope with a steep slope.
Weeds such as scum and susuki are easy to invade, the weeds are also left and enlarged, and weed management such as covering plants is necessary for mowing and weed control by harvesting. Enormous effort is required for management such as disposal.
Furthermore, it is an important issue that the concrete used in these methods must be disposed of as industrial waste.
JP 2003-278163 A

Therefore, the present invention provides a solidified layer mainly composed of pure sand soil in the soil, and a humus soil layer composed of bark crushing material, plant seeds and humus soil is disposed on the solidified layer, so that the plant has a certain level or more. In addition to forming a sloped structure that does not grow higher than the height, when forming its solidified layer and humus soil layer, devise so that it can be quickly and stably formed even on a steep slope exceeding 30 degrees, for example. It is a fancy thing.

In order to achieve the above object, the slope structure according to claim 1 is 10 to 20 parts by weight of Portland cement and 0.1 to 0. On a slope spray solidified layer composed of 5 parts by weight and 20 to 30 parts by weight of river sand with a particle diameter of 2.5 mm, 15 to 20 parts by weight of bark crushing material and 5 to 10 parts by weight of plant seeds And 5 to 10 parts by weight of humus soil is formed.

The method of constructing a slope structure according to claim 2 comprises arranging a wire mesh on the slope, and 10 to 20 parts by weight of Portland cement, 100 parts by weight of Portland cement with respect to 100 parts by weight of sand sand. Spraying the slope sprayed soil composed by adding 0.1 to 0.5 parts by weight of activator and 20 to 30 parts by weight of river sand with a particle size of 2.5 mm, and surface hardening time of the sprayed solidified layer Inside, humus soil consisting of 15 to 20 parts by weight of bark crushing material, 5 to 10 parts by weight of plant seeds, and 5 to 10 parts by weight of humus soil is sprayed.

The composition mixture of the present invention forms a humus soil layer composed of solid sand and bark crushing material, plant seeds and humus as the main component. Growth does not grow above a certain height, and maintenance after the growth, such as cutting, becomes unnecessary.
At the time of the construction, the composition is composed of river sand having a large specific gravity and a particle diameter of 2.5 mm, so that it can be sprayed even at a certain distance and the spraying time is shortened. . Even after the spraying, even if it is a steep slope of more than 30 degrees, the avalanche phenomenon can be suppressed downward.
At the time of final disposal, blending of Portland cement, surfactant, etc. into sandy sand, river sand, etc. is appropriate so that it can be easily crushed, can be reduced to natural soil and excluded from industrial waste handling.

Therefore, an embodiment of the present invention will be described.
The present invention comprises a slope spray composition composed of pure sand, Portland cement, a nonionic surfactant and river sand, and a slope spray humus soil composed of bark crushed material, plant seeds, and humus.
Hereinafter, the characteristics of the constituent materials will be described.

Masa sand, which is one of the sprayed solidified layers, is a soil made by weathering mainly granite from mountain sand and is an aggregate excluding clays such as volcanic ash. The particle size is usually 2 mm or less, with a coarse particle size (2 to 0.5 mm), a fine particle size (0.5 to 0.075 mm), or a fine particle size (0.075 mm). Is a material that has both water retention and water permeability properties that can be stored in a porous form in which air and water can be stored.

Portland cement substantially surrounds the surface of the true sand soil and binds the particles of the true sand soil to form a number of voids. Portland cement also solidifies river sand and pure sand soil together and plays the role of holding the solidified layer in a porous form. However, although Portland cement can largely maintain the bonding force between aggregates, it tends to be a dumpling or a lump and easily fills voids. Therefore, a small amount is desirable, and 10 to 20 parts by weight per 100 parts by weight of pure sand soil. Part by weight is suitable.

Nonionic surfactants have the property of enhancing the wettability of pure sand soil, uniformly dispersing Portland cement on the surface of the true sand soil, and suppressing the surface tension of water to enable uniform water retention and water permeation. When Portland cement is evenly dispersed on the surface of the true sand, moderate strength appears as a solidified layer. On the other hand, if the Portland cement is not uniform on the surface of the true sand soil, it becomes dumplings and lumps, where strong and weak parts are born, and in the weak parts, the roots of the plants grow and the plants grow greatly. In order to prevent the growth of the plant, it is possible to improve the dispersion of the Portland cement and to achieve the surface hardening of the spray-solidified layer.
A nonionic surfactant is used as the surfactant responsible for improving the wettability and dispersibility of the compounding agent.

A solidified layer having water permeability and water retentivity can be formed by the composition of the above composition, but with this alone, (i) the specific gravity is too light and particles are scattered around when sprayed at a constant pressure, and the slope is (B) Also, after spraying, fine particles may collapse due to their own weight and cause a kind of snow collapse phenomenon.
Therefore, attention is paid to the river sand under the mesh size of 2.5 mm.
The river sand consists of quartz, feldspar, etc. derived from sandstone and granite, classified as sandy soil, but has a relatively large specific gravity, depending on the size of the specific gravity, against the spraying pressure when performing the spraying work, for example, This is because it is possible to fly to the target slope of about 1 to 2 meters.
The river sand with a particle diameter of 2.5 mm is selected. The reason is that if the particle diameter is 2.5 mm or more, the mixing with the true sand soil is poor and tends to settle down. If the particle diameter is 2.5 mm, the mixture is uniformly mixed with the true sand soil. In addition, it is possible to secure some fluidity necessary for spraying. Furthermore, the river sand under the sieve size of 2.5 mm is coarse soil and low in the circularity of the particles. Therefore, when mixed with pure sand, the gel property increases. The so-called avalanche phenomenon that slides down after spraying is not caused.

Next, the bark crushing material constituting the slope sprayed humus soil layer is obtained by recycling the bark of the felled tree. It is an environmentally friendly organic soil conditioner that mainly deposits bark of broadleaf trees and conifers for a long period of time to form compost, pulverizes the bark to adjust the moisture, and provides a ripening period.
The bark crushed material increases water supply and water retention, supplies moisture and nutrients necessary for germination to the seeds, and protects the plant from drying even during subsequent growth.
Further, since the crushed bark crushed material is entangled with its fibers, when the seeds after germination have extended their roots, the roots and the fibers are entangled with each other to fix the whole plant.

The humus soil is a deciduous compost made by turning the fallen leaves of a broad-leaved tree once every 2 to 3 months and ripening in about 2 years. Then supplement the missing nutrients.

The solidified layer allows plant hair roots to enter the voids and promotes fixation to the slope with the hair roots. On the other hand, since the intrusion of thicker roots is suppressed, the expansion of the root zone is suppressed, and the plant is allowed to grow in a certain range, but the growth to a tall plant is suppressed.

The Example of this invention was manufactured based on the said embodiment. Table 1 shows the composition of the slope spray solidified layer of the present invention, and Table 2 shows the test composition and the characteristics up to the composition of the slope spray solidified layer of the present invention. Table 3 shows the composition of a general slope sprayed humus soil and describes the method of forming a slope structure with the slope spray solidified layer of the present invention.

Table 1 shows the composition of the slope spray solidified layer of the present invention. In order to blend this composition, 25 parts by weight of river sand having a particle size of 2.5 mm is collected, and 100 parts by weight of pure sand soil, 15 parts by weight of Portland cement, and 0.1 part by weight of a nonionic surfactant are included. After mixing with the spray composition, 10 parts by weight of water was added and stirred.
Then, since the apparent specific gravity of the mixed composition was increased, the mixture composition was not scattered in all directions and could be fixed by flying 1 to 2 meters toward the target slope. Moreover, since the soil does not scatter, it was possible to spray the desired position.

Next, Table 2 shows the test composition and the characteristics up to the composition of the slope spray solidified layer of the present invention.

The composition of Table 2 (a) is sprayed soil without river sand, and when this sprayed soil is laid with a slope of 30 degrees, the apparent specific gravity is small, so it is lightweight and splashes in all directions when sprayed. It was. As a result, the slope surface did not become smooth, and it became a sprayed state with bumps in a bumpy state. In such a state, the sprayed soil could not be fixed on the sprayed surface, and the surface layer peeled off from the slope and fell off.
The composition of Table 2 (b) is a composition with 10 parts by weight of river sand added. In this composition, the slope surface is somewhat smoother than the composition of Table 2 (a) above, The attached state remained.
The composition of Table 2 (C) is a composition in which 20 parts by weight of river sand is added to the spray solidified layer. In this composition, the slope surface becomes smoother by several steps than the composition of Table 2 (B) above. It became a spraying state without ups and downs. This composition is shown in Table 1 above, and is a composition composition of the slope spray solidified layer of the present invention.
Furthermore, Table 2 compared the construction efficiency of this slope spray solidified layer and spray soil without river sand. That is, the spraying construction time was 20 minutes, and the degree of improvement in construction efficiency was determined by the spraying area at that time. As a result, the slope spray solidified layer was 15 m ² , the general spray soil was 3 m ² , and the slope spray solidified layer of the present invention improved the construction efficiency by 5 times.

As shown in FIG. 1, the solid sand and river sand surfaces are substantially surrounded by cement, and the particles of the sand sand and river sand are bonded by cement and have a large number of voids. In addition, the surfactant improves wettability of pure sand and cement, suppresses the surface tension of water, and increases water permeability and water retention.

The following Table 3 shows the composition of a general slope spray humus soil, and the method for forming a slope structure with the slope spray solidified layer of the present invention will be described.

Table 3 shows the composition of the slope sprayed humus soil layer of the present invention.
The said slope structure means the structure formed with this slope spraying humus soil layer and the slope spray solidification layer of this invention. In order to form the slope structure on the soil surface of the slope with a slope of 30 degrees, a wire mesh was stretched as a secondary material. The wire mesh has a function of protecting the spray-solidified layer from releasing or delamination from the soil surface.
After the construction of the wire mesh, the slope sprayed solidified layer consisting of 100 parts by weight of pure sand, 25 parts by weight of river sand, 15 parts by weight of Portland cement and 0.1 parts by weight of nonionic surfactant is added to the slope. Sprayed at 4-5 cm. Thereafter, a curing time of the slope spray solidified layer of about 8 to 12 hours in summer and about 24 hours in winter is provided, and finally, 17 parts by weight of bark crushed material, 8 parts by weight of plant seeds, 8 of humus The sloped humus soil consisting of parts by weight was sprayed about 3 to 5 cm to form the sloped structure.

In the slope structure formed above, seeds grow in the slope sprayed humus soil layer, and eventually the root sticks to the surface of the slope spray solidified layer of the present invention, and only the hair root part enters the gap. .
However, further root growth is suppressed by the solidified layer of pure sand and river sand, the roots of the vegetation cannot proceed any further, the expansion of the root area is suppressed, and the plant does not grow tall. The so-called vegetation grows in a restrained manner. Plants and shrubs grew, but large trees did not grow, because vegetation roots were restrained from expanding into the spray-solidified layer.
As a result, weed control by mowing and handing becomes unnecessary, and management labor is greatly reduced.

  At the time of final disposal, blending of Portland cement, surfactant, etc. into sandy sand, river sand, etc. is appropriate so that it can be easily crushed, can be reduced to natural soil and excluded from industrial waste handling.

The present invention mainly provides a composition and a slope structure for spraying a slope having a steep slope exceeding 30 degrees, and a construction method thereof, but is used for a slope having a relatively gentle slope. It is also possible to do.

FIG. 1 is a schematic enlarged cross-sectional view showing the particle distribution of the slope structure of the present invention.

Claims (2)

10 parts by weight of Portland cement, 0.1 to 0.5 parts by weight of nonionic surfactant and 20 to 30 parts by weight of river sand with a particle size of 2.5 mm are added to 100 parts by weight of pure sand. A humus soil layer comprising 15 to 20 parts by weight of bark crushing material, 5 to 10 parts by weight of plant seeds, and 5 to 10 parts by weight of humus soil on the slope sprayed solidified layer .   A wire mesh is provided on the slope, and 10 to 20 parts by weight of Portland cement, 0.1 to 0.5 parts by weight of a nonionic surfactant and a particle diameter with respect to 100 parts by weight of sand sand by weight. Slope sprayed soil composed by adding 20 to 30 parts by weight of river sand under 2.5 mm sieve is sprayed, and within 15 to 20 parts by weight of bark crushing material and plant seeds within the surface hardening time of the sprayed solidified layer A method for constructing a slope structure, characterized by spraying humus soil of 5 to 10 parts by weight and 5 to 10 parts by weight of humus.