JPH0931957A - Reinforcing material for sand ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To disperse a reinforcing material in sand to increase the frictional coefficient between the sand and the reinforcing material, and prevent distortion of the sand ground to be caused by the weight of a heavy material, by forming the sand ground-reinforcing material having a specified shape in a net structure having voids. SOLUTION: A net structure of a specified sectional shape while a number of continuous weirs made of a thermoplastic synthetic resin polymer having 0.1-1.5mm diameter are longitudinally bent to form loops, and it is cut in a specified length, to mix with the sand ground as a reinforcing material for the sand ground. In each continuous wire, the stuck quantity of the contact points with adjacent wires is 100-4,000g/m<2> , the void ratio is 20-90%, the bending elastic modulus is 10-15,000kgf/cm<2> and it has a constant sectional shape in the longitudinal direction. A longitudinally continuous fin part 4 is arranged at the side of the body 3 to have the fin part with a small rigidity in common. In this way, the net structure serves as a kind of resistant material by mixing with sand to improve the dispersing effect of the reinforcing material. And the reinforcing material is prevented in sand from sliding with external forces to make effective the reinforcement of ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced sand ground or turf grass vegetation base, more specifically, a base of a sand ground or turf grass vegetation such as an outdoor playground, a golf course, a racetrack or a racetrack The present invention relates to a sand ground reinforcing material for reinforcing a ground.

[0002]

2. Description of the Related Art In order to reinforce the base of the road surface portion such as the above-mentioned plaza and runway, for example, JP-A-59-13090 is known.
A flexible mesh element as disclosed in Japanese Patent No. 9 is mixed with sand to form a base, or, for example, a chip-shaped object made of cedar bark is mixed with sand to be installed to reinforce the roadbed portion, or For example, there is a facility where only the bark chips are sprayed on the road surface.

[0003]

However, Japanese Unexamined Patent Publication No.
When a flexible mesh element is mixed with sand as in Japanese Patent Publication No. 9-130909, a mixed soil in which the mesh elements are uniformly dispersed in the sand is obtained due to the difference in specific gravity between the sand and the mesh element. Therefore, strong and weak parts of the base occur when reinforced with the above mixed soil, and when a heavy load is applied, the weak part of the base collapses, resulting in damage to the base layer. .

Further, when a chip-like material made of cedar bark is mixed with sand, the chip-like material absorbs excessive water in the sand, so that the chip-like material becomes soft and the effect of reinforcing the base is improved. May decrease.

Further, hemicellulose such as lignin leaching from the bark mixes with dust of sand grains and flows out as sewage due to rainwater, or the bark is crushed into fine powder by the load of heavy objects, which causes There is a risk that the drainage function of the sand layer or aquifer may be reduced.

[0006]

The present invention has a diameter of 0.1.
mm to 1.5 mm, each of a large number of continuous filaments of a thermoplastic synthetic polymer extends in the longitudinal direction while irregularly bending three-dimensionally, and each continuous filament has a contact point of an adjacent continuous filament. Most of them are bonded to each other with a basis weight of 100 g / m ² -4
000 g / m ² , porosity 20% to 90%, flexural modulus 10 to 15000 kgf / cm ² in a sheet-like or tubular reticulate structure having a constant cross-sectional shape in the longitudinal direction. Is.

Further, a preferred embodiment of the present invention is the above-mentioned sand ground reinforcing material having fin portions continuous in the longitudinal direction on the side of the net-like structure.

Another preferred embodiment of the present invention is the above-described sand ground reinforcing material having a structure having a void core inside a net-like structure.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the synthetic polymer forming the continuous filaments include polymers such as polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polyamides such as nylon 6 and nylon 66. Alternatively, the above-mentioned two or more copolymers or copolymers such as styrene-butadiene copolymer and polypropylene-ethylene-butene copolymer may be used alone or in combination of two or more. Considering pressure resistance, bending strength, durability, etc., styrene-butadiene copolymer and polypropylene-ethylene-
A mixture of butene terpolymers is preferred.

The sand ground reinforcing material of the present invention has a shape as shown in the perspective view of FIG. The sand ground reinforcing material (1) is composed of an assembly of continuous filaments (2), and the continuous filaments (2) have a three-dimensional net structure continuous in the longitudinal direction in a loop shape that is irregularly bent while maintaining a predetermined cross-sectional shape. The adjacent continuous filaments are bonded at each contact point.

The cross-sectional shape of the sand ground reinforcement is shown in FIG.
As shown in (G) to (G), there are, for example, a rectangle, an ellipse, a rhombus, a triangle, a semicircle, a V-shape, or a circle, and the shape is not specified.

The diameter of the continuous filaments forming the three-dimensional network structure is preferably 0.1 mm to 1.5 mm. If the diameter is 0.1 mm or less, strength and rigidity are insufficient, and conversely the diameter is 1. If it is 0.5 mm or more, the strength is increased, but it exceeds the appropriate rigidity as a sand ground reinforcing material and is unsuitable.

The basis weight of the three-dimensional net-like structure is 100 g / m ² to 40 in order to obtain appropriate rigidity as a sand ground reinforcing material.
00 g / m ² is desirable. Particularly, when the basis weight of the three-dimensional network structure is 4000 g / m ² or more, not only the rigidity becomes excessive but also the porosity becomes small and the air permeability or water permeability is lowered.

In the present invention, the thickness of the reinforcing material is 2 mm to 30 mm in consideration of the proper rigidity of the sand ground reinforcing material, the uniformity when mixed with the sand particles, the entanglement with the sand particles, and the like.
Length in the longitudinal direction is 5 mm to 200 mm, porosity is 20%
90% is preferable. Especially, the porosity is 20%
If it is less than the following, the rigidity will be too high, and the ground tends to be a foreign object. On the other hand, if it is more than 90%, the strength of the sand ground reinforcement will be significantly reduced, causing damage to the base due to the load of heavy objects. Becomes

Since the sand ground reinforcing material is repeatedly subjected to bending stress due to the load of heavy objects, etc., it shows flexibility enough to be flexibly bent when a large amount of energy is applied, and is restored after bending. It is desirable to maintain the shape and reinforce the ground. Therefore, flexural modulus at the reinforcing member is preferably a ^{10kgf / cm 2 ~15000kgf / cm 2} .

In the sand ground reinforcing material of the present invention, as shown in the perspective view of FIG. 1, fin portions (4) continuous in the longitudinal direction are formed on the sides of the body portion (3) of the three-dimensional net structure. The ground reinforcement can be made effective by forming them. That is, the reinforcing material in which the fin portion is arranged on the body portion shares the fin portion having low rigidity, thereby alleviating the discomfort due to the hardness of the body portion having high rigidity,
When mixed with sand, it becomes a kind of resistor to improve the dispersion of the reinforcing material, and when in the sand, the sliding of the reinforcing material can be suppressed by an external force.

The sandy reinforcing material of the present invention may be provided with a void core portion (5) inside the reinforcing material as shown in the sectional view of FIG. With such a structure, excessive water in the sand due to rainwater or the like is held together with the sand in the void core portion of the reinforcing material, so that the water in the sand ground is held for a long period of time and the ground is reinforced. In addition, the sand held in the void core also has the effect of increasing the weight per reinforcing material and improving the dispersion with sand.

Due to the presence of water in the sand, the sand ground reinforcement is
By increasing the coefficient of friction between sand and sand, a ground reinforcement effect that can withstand external forces such as loads such as heavy objects appears,
It is also possible to carry hydrophilic particles such as cellulose fibers or water absorbent particles such as superabsorbent polymers on the sand ground reinforcing material. For that purpose, at the time of producing a three-dimensional network structure, which will be described later, at the same time as spinning the continuous filaments, a predetermined amount of the cellulose fiber or the superabsorbent polymer is supplied to the carrier and enclosed in the network structure.

[0019]

The present invention will be described in more detail with reference to the following examples.

[Example 1] A mixture of 40% styrene-butadiene copolymer and 60% polypropylene-ethylene-butene terpolymer was used as a raw material, and the spinneret (6 From the above), a melt of the above mixture was spun into a continuous filament (2), and the intersections of adjacent continuous filaments were adhered to each other while naturally cooling this on the carrier (7). At this time, the feeding speed of the carrier is slower than the spinning drop speed of the continuous filaments, and the continuous filaments are accumulated on the conveyor in an irregular loop.

The spinneret (6) used is a spinneret (8) arranged as shown in FIG. Further, the carrier is an endless belt in which the units (9) shown in FIG. 6 are continuously connected.
The unit (9) has a mountain portion (10) and a valley portion (11) which are continuous in the longitudinal direction, and a continuous wire spun from a portion (8-A) having a high density of spinning holes among continuous filaments. The filaments are accumulated in the troughs (11) of the unit, and the continuous filaments spun from the portion (8-B) having a small number of spinning holes are accumulated in the peaks of the unit.

The thus obtained product is a body portion (3) having a width of 28 mm and a thickness of 10 mm as shown in FIG.
And a wide and continuous three-dimensional net-like structure having fin portions (4) having a thickness of 4 mm and connected to each other.

This three-dimensional net-like structure was cut at the center of the fin portion and further cut to a predetermined length of 100 mm to obtain the sand ground reinforcing material of the present invention.

Next, using the above-mentioned sand ground reinforcing material of the present invention, a sand horse field having a structure shown in the sectional view of FIG. 8 was constructed. FIG.
In the lower layer, the thickness of the drainage drain (12) is 2
The crushed stone water-permeable layer (13) of 0 cm and the sand layer (14) of 40 cm in thickness are the middle layers. On this, fine sand was mixed with 0.5% by weight of the sand ground reinforcing material (1) of the present invention to form a Baba running surface having a thickness of 10 cm.

[Example 2] A three-dimensional net-like structure was manufactured by the apparatus shown in FIG. The same melt as in Example 1 was spun into continuous filaments (2) with a spinneret (6) having the arrangement of spinning holes (8) shown in FIG. Immediately after spinning, the continuous filaments (2) were introduced into normal-temperature water filled in the cooling tank (15) and spirally crimped and mutually adhered and solidified.

This continuous linear body was carried out of the cooling tank by a feeding roller and cut into a length of 10 cm to obtain a sand ground reinforcing material having a cross section shown in FIG.

The above-described sand ground reinforcement was used in the same sandy stadium as in Example 1, and turfgrass was vegetated on the sandbed for 3 months. As a result, the turfgrass grew smoothly and the roots became the sand ground reinforcement. It was reinforced. When a horse racing machine was installed on it, the subsidence of the ground under the wheels was only a few cm,
In addition, the part where the wheel load was applied was restored almost as it was when the load was released.

[0028]

EFFECTS OF THE INVENTION Since the sand ground reinforcing material of the present invention has a mesh structure having voids, if it is dispersedly laid in the sand, the coefficient of friction with the sand will increase and the sand ground will be distorted by the load of heavy objects. Suppress. In addition, the voids of the reinforcing material introduce and retain excess water and air of the sand ground into the voids of the reinforcing material, and as moisture and air are released from the inside of the reinforcing material as the sand dries, growth of plants such as turfgrass, It is useful for cultivation, prevents root cutting and root rot of turf grass, and is effective for growing vegetation such as turf grass.

Further, in addition to the above-mentioned usage, the sand ground reinforcing material of the present invention can be laminated on the sand ground for 10 to 20 cm to form a training chip riding ground.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a sand ground reinforcing material of the present invention.

FIG. 2 is a view showing a cross-sectional shape of the sand ground reinforcement material of the present invention.

FIG. 3 is a cross-sectional view showing an example of the structure of the sand ground reinforcing material of the present invention.

FIG. 4 is a chart diagram showing an outline of an apparatus for manufacturing a sand ground reinforcing material of the present invention.

FIG. 5 is a plan view showing an example of a spinneret for spinning out continuous filaments constituting the sand ground reinforcing material of the present invention.

FIG. 6 is a perspective view showing a unit of a carrier of the sand ground reinforcement manufacturing apparatus of the present invention.

FIG. 7 is a perspective view showing a shape before cutting of the sand ground reinforcement material of the present invention formed by the unit of FIG.

FIG. 8 is a cross-sectional view showing a sand ground structure of a horse riding ground using the sand ground reinforcing material of the present invention.

FIG. 9 is a chart diagram showing an outline of an apparatus for manufacturing a sand ground reinforcing material of the present invention.

FIG. 10 is a plan view showing an example of a spinneret for spinning a continuous filament product that constitutes the sand ground reinforcing material of the present invention.

FIG. 11 is a cross-sectional view showing an example of the structure of the sand ground reinforcing material of the present invention.

[Explanation of symbols]

 1 Sand Ground Reinforcing Material 2 Continuous Wire 3 Body 4 Fins 5 Void Core 6 Spinneret 7 Conveyor 8 Spinning Hole 9 Unit 10 Mountain Part 11 Valley 12 Drain Drain 13 Crushed Water Channel 14 Sand Layer 15 Cooling Tank

Claims (3)

[Claims] 1. A plurality of continuous filaments of a thermoplastic synthetic polymer having a diameter of 0.1 mm to 1.5 mm each extending in the longitudinal direction while irregularly bending in three dimensions, and each filament is Most of the contact points of the adjacent continuous filaments are adhered to each other. The basis weight is 100 g / m ^{2 to} 4000 g / m ² , the porosity is 20% to 90%, and the bending elastic modulus is 10 to 15000 kgf.
A sand ground reinforcing material in a sheet-like or tubular mesh structure having a constant cross-sectional shape in the longitudinal direction of / cm ² . 2. The sand ground reinforcing material according to claim 1, which has fins continuous in the longitudinal direction on the side of the mesh structure. 3. The sand ground reinforcing material according to claim 1, which has a void core portion inside the net-like structure.