JPH09268545A - Soil-structural reinforcing material and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To add to a soil-extraction resistance and thereby preclude the slipping phenomenon of soil by forming specific projections on the lattice-like fiber sheet in a soil structural reinforcing material to be placed in soil for the purpose of weak ground reinforcement, banking reinforcement, or the like. SOLUTION: Projections 2 are formed at the intersections of warp thread 4 and weft thread 5 of a lattice-like knitted fiber sheet 2 by a chain stitch of chain stitch thread 6 of warp thread 4 and weft thread 5, and a synthetic resin 3 is impregnated in the fiber sheet 2 to completely sheathe the fiber sheet 2 and form a soil-structural reinforcing material 1. Projections 7 consisting of a fiber can be made of connection threads by cutting the central part of connection threads of a lattice-like knitted fabric having a double-knitted structure and separating the knitted fabric into a front and rear part. The height of the projections is 1-30mm, and the lattice of the ground structure has a length of one side of 10-100mm. Accordingly, a soil-extraction resistance is increased through a bridging and engaging effect between the projections 7 and the upper and lower soil over the lattice, thus preventing a soil slipping phenomenon.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil structure reinforcing material installed in soil for the purpose of reinforcing soil structures such as soft ground reinforcement and embankment reinforcement.

[0002]

2. Description of the Related Art Conventionally, a reinforced non-woven fabric or a woven fabric has been mainly used as a soil structure reinforcing material for the purpose of reinforcing a soil structure such as soft ground reinforcement and embankment reinforcement. The resistance was not sufficient and the slip phenomenon of soil was likely to occur. In recent years, a net-like sheet in which a lattice-like fiber sheet is impregnated with a resin, as proposed in Japanese Patent Application Laid-Open No. 5-125733 and Japanese Patent Publication No. 6-32977, is often used, and the slip phenomenon of soil is remarkably increased. Has been improved. Further, in Japanese Patent Laid-Open No. 63-70720, a net-shaped sheet in which fiber bundles arranged in a rope shape, a tape shape, or a strip shape are arranged in a net shape and impregnated with a resin is further described. There is disclosed a net-like sheet having a protrusion formed of.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The sheets described in Japanese Patent Publication No. 733 and Japanese Patent Publication No. 6-32977 have the ability to prevent the slipping phenomenon of soil, but they are not sufficient yet. In addition, JP-A-63-
The sheet having protrusions described in Japanese Patent No. 70720 has the ability to further prevent the slipping phenomenon of soil, but it is not sufficient such that the protrusions fall off when the sliding phenomenon of soil occurs, It also has a technical problem in manufacturing.

The present invention has been made in view of the above-mentioned situation, and it is possible to prevent the sliding phenomenon of soil, effectively reinforce the soil structure, and easily form projections. An object of the present invention is to provide a reinforcing material and a manufacturing method thereof.

[0005]

The present invention achieves such an object and has the following configuration. That is, the present invention is a soil structure reinforcing material, characterized in that a synthetic resin is impregnated into a fiber sheet in which projections of fibers having a height of 1 to 30 mm are formed and the ground structure is a lattice structure. And 1 to 30 by cutting the connecting yarn of the woven or knitted fabric having a double structure in which the ground structure is a lattice structure
A gist of the present invention is to provide a method for producing a reinforcing material for an earth structure, which comprises impregnating a synthetic resin into a fiber sheet having protrusions with a height of mm.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

FIG. 1 is a schematic view showing an example of the basic form of the earth structure reinforcing material of the present invention.
Is obtained by impregnating a synthetic resin 3 into a fiber sheet 2 in which projections are formed and the ground structure is a lattice structure.

FIG. 2 is a schematic cross-sectional perspective view of a cross section of the lattice of the fiber sheet shown in FIG.
The ground structure of the fiber sheet 2 is knitted in a substantially straight line without forming a loop, and the weft yarn 5 inserted in the transverse direction is joined by chain knitting of the chain knitting yarn 6 to form a lattice shape, At the intersection of the warp and weft of the tissue, a protrusion 7 made of fibers
Are formed. And in this figure, the fiber sheet 2
Is impregnated with the synthetic resin 3 and is completely covered with the synthetic resin 3. Although FIG. 2 shows an example in which the protrusions 7 are formed side by side with three wales, only one wale may be formed, or more wales may be formed continuously. Further, in the course direction, only one course may be formed, or a plurality of courses may be continuously formed. Further, it may be formed continuously on the side of the lattice in the warp direction or continuously on the weft direction.

In order to increase the pull-out resistance in order to prevent the soil sliding phenomenon of the earth structure, it is necessary to set the height of the protrusion protruding from the ground texture surface of the fiber sheet to 1 to 30 mm. It is preferably 3 to 20 mm, and if it is less than 1 mm, the frictional resistance with soil is not improved and the object of the present invention is not achieved, and if it exceeds 30 mm, the possibility of buckling during construction becomes large and the present invention is difficult. The purpose will not be achieved.

The length of one side of the lattice of the fiber sheet is 10 to 10.
It is effective to set it to 100 mm. This is because the type of soil used for the soil structure is very small particles,
There are various types such as rubble, crushed stone, natural soil mixed with soil and stone, and residual soil derived from civil engineering or construction sites.Since appropriately selected soil is used for earth structures, soil and soil This is to effectively exert the bridge or meshing effect with, and the friction resistance or pull-out resistance with the reinforcing material installed in the soil. The length of one side of the lattice is
If it is less than 10 mm, the effect of bridging or meshing of the soil through the reinforcing material cannot be expected, and if it exceeds 100 mm, it becomes difficult to obtain the necessary strength for reinforcement, and depending on the type of soil, the effect of preventing soil slippage may be reduced. May be damaged.

The fiber used in the fiber sheet of the present invention may be selected according to the required performance depending on the application and is not particularly limited, but may be polyamide, polyester, vinylon, aramid, polypropylene, acrylic. Glass, carbon fiber, etc. are preferably used, and any of these multifilaments, monofilaments, or spun yarns may be used, and the undyed fiber colored at the time of fiber production may be used.

A fiber sheet having protrusions made of fibers is
It can be obtained by cutting the connecting yarn of a woven or knitted fabric having a double structure in which the ground structure is a lattice structure. A woven or knitted fabric having a double structure in which the ground structure is a lattice structure is, for example, 2
It can be manufactured by forming a grid-like ground structure on the front and back using a double russel having a needle bed and a moquette loom, and connecting them at intervals with connecting threads. As shown in FIG. 3, when the central portion of the connecting yarn 9 of the woven and knitted fabric 8 having a double structure is cut with a cutter knife 10 or the like to separate it into the front side and the back side, the cut connecting yarn forms a protrusion 7 made of fibers. As a result, the fiber sheet 2 of the present invention is obtained.

In the present invention, the type of synthetic resin impregnated into the fiber sheet is not particularly limited, but vinyl chloride resin, acrylic resin, epoxy resin, vinyl ester resin, unsaturated polyester resin, phenolic material, etc. may be used. It is preferable to use it, and above all, it is preferable to use a curable resin in order to finish the projection portion hard to maintain the uprightness of the projection. If necessary, additives such as curing agents, accelerators, pigments, and fillers such as talc, gypsum, clay, and calcium carbonate may be mixed and used in the synthetic resin.

In the present invention, the method for impregnating the fiber sheet with the synthetic resin is not particularly limited, and means such as dipping, coating, spraying and painting can be used, and these may be used in combination. . Also,
During impregnation, by increasing the amount of synthetic resin applied to completely cover the fiber sheet, including the protrusions, it is possible to protect the fiber sheet from abrasion during construction and to prevent deterioration of strength and durability. Effective to maintain. In this case, a plurality of protrusions formed on the fiber sheet may be simultaneously covered so that the protrusions can be seen as one protrusion.

[0015]

Since the soil structure reinforcing material of the present invention is in the form of a lattice, the voids in the soil structure exert a bridge or meshing effect on the upper and lower soils to increase the pull-out resistance in the soil and from the molecularly oriented fibers. As compared with a conventional net-shaped sheet or a net-shaped sheet provided with a projection made of resin, the resistance to pulling out into the soil becomes larger, and the slip phenomenon of the embankment soil and the soil The effect of preventing subsidence is remarkably excellent.

[0016]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited thereto.
The evaluation of the performance in the examples was performed by the following method.

(1) Cutting Strength and Cutting Elongation Measured in a width of 5 cm according to JIS L-1069, and the cutting strength (kg) was converted into a width of 1 m.

(2) Pull-out resistance Soil tank of Maruto Seisakusho's soil pull-out tester (width 500 mm, length
(800 mm, height 200 mm), put Toyoura standard sand with a compaction degree of 1.525 tf / m ² together with a sample with a width of 450 mm and a length of 500 mm.
0.2 kgf / cm ^2, measured pullout resistance (kg) at ^{0.4kgf / cm 2, 0.6kgf / cm} 2 and 3 pull change the phase speed of 1 mm / min,
Converted to 1m width.

Example 1 Using a weft insertion type two-row needle bed 6-gauge warp knitting machine having a device capable of intermittently feeding warps by computer control, the reeds L1, L3, L4 and L6 have a strength of 12 g according to the structure of FIG. / d,
Total of 3 twists of 1200d / 250f vinylon yarn with 6% elongation
Thread 3600 denier yarn 3 in-3 out and reed L2 and L
In No. 5, 550d / 250f with a strength of 8.5g / d and elongation of 20% was threaded in 2in-4out, and a total of 7200 denier yarns in which 6 of the above vinylon yarns were twisted as wefts in 1in-8out. Wefts were inserted on the front and back sides, and a 20 mm-thick lattice-shaped three-dimensional fabric was knitted. The size of the lattice of the obtained cloth was 20 mm measured from center to center in both the longitudinal and transverse directions.

The obtained lattice-shaped three-dimensional fabric was cut with a center-cutting machine at the central portion as shown in FIG. 4 to cut the connecting yarn formed by the reeds L3 and L4 for connecting the front and back tissues. As a result, a grid-like fiber sheet having protrusions made of fibers was obtained. At this time, the height of the protrusion was 8.5 mm.

The obtained fiber sheet was impregnated with a vinyl chloride resin liquid having the following composition and heat-treated at 150 ° C. for 3 minutes to obtain a soil structure reinforcing material of the present invention.

[Vinyl chloride resin liquid composition] -Vinyl chloride resin Hestresin 100 parts (Zeon 121 manufactured by Zeon Corporation) -Diocterphthalate (plastic material) 40 parts-Methyl isobutyl ketone / naphthene-based thinner 10 parts (diluent, Volume ratio 1/1) Example 2 In Example 1, the thickness of the lattice-shaped three-dimensional fabric was 33 mm,
An earth structure reinforcing material of the present invention was obtained in the same manner as in Example 1 except that the height of the protrusions after center cutting was 15 mm.

Comparative Example 1 In Example 1, the lattice-shaped three-dimensional fabric has a thickness of 3 mm,
A soil structure reinforcing material of a comparative example was obtained in the same manner as in Example 1 except that the height of the protrusion after the center cut was 0.5 mm.

Comparative Example 2 In Example 1, the lattice-shaped three-dimensional fabric has a thickness of 67 mm,
A soil structure reinforcing material of a comparative example was obtained in the same manner as in Example 1 except that the height of the protrusion after center cutting was 32 mm.

Comparative Example 3 Using a weft insertion type single Russell 6 gauge knitting machine, FIG.
With a structure of 3), a total of 3600 denier yarn is obtained by twisting three 1200d / 250f vinylon yarns having a strength of 12g / d and an elongation of 6% to the reed L1.
Threaded in 3in-3out, the reed L2 has a strength of 8.5g / d and an elongation of 20%.
550d / 250f is threaded in 2in-4out and the reed L3 has strength 8.5g /
d, thread 550d / 250f with 20% elongation at 3in-3out, and weft-inserted 6in total 7200 denier yarns with 6 vinylon yarns as above and weft-inserted at 1in-8out. A grid-like fiber sheet of 20 mm was obtained by measuring the center in the longitudinal direction and the center in the lateral direction.

The obtained fiber sheet was impregnated with the same vinyl chloride resin solution as in Example 1 to obtain a soil structure reinforcing material of a comparative example.

Comparative Example 4 The fiber sheet of Comparative Example 3 was impregnated with a vinyl chloride resin solution, and projections with a diameter of 3 mm and a height of 8 mm were formed at the intersections of the lattice to obtain a soil structure reinforcing material of Comparative Example. It was

Table 1 also shows the evaluation results of the soil structure reinforcing materials obtained in Examples 1 and 2 and Comparative Examples 1 to 4.

[0029]

[Table 1]

As is clear from Table 1, Examples 1 and 2 of the present invention are Comparative Example 3 in which no protrusions are present, Comparative Example 1 in which the height of the protrusions is low, and Comparative Examples having protrusions made of resin only. Four
It is an excellent soil structure reinforcement material with improved pull-out resistance compared to. Further, when the height of the protrusions made of fibers becomes high as in Comparative Example 2, the pull-out resistance tends to decrease, probably because the protrusions are crushed when the overloading pressure is high.

[0031]

EFFECT OF THE INVENTION The earth structure reinforcing material of the present invention has excellent resistance to pulling out into the soil, and a suitable earth structure reinforcing material having high strength and low elongation can be obtained. By laying an appropriate amount in the soil, the ground support capacity is improved,
It is possible to prevent uneven settlement of the ground, prevent slippage of soil, prevent collapse, and improve the durability of soil structures.

[Brief description of drawings]

FIG. 1 is a schematic view of a soil structure reinforcing material of the present invention.

FIG. 2 is a cross-sectional perspective view of the soil structure reinforcement material of one example of the present invention cut laterally.

FIG. 3 is a diagram showing a state in which a fiber sheet is obtained by center-cutting a knitted fabric having a double structure.

FIG. 4 is a structure diagram showing an example of the structure of a knitted fabric having a double structure that can be used in the present invention.

FIG. 5 is a structural diagram of a fiber sheet used in a comparative example.

[Explanation of symbols]

 1 Earth Structure Reinforcement Material 2 Fiber Sheet 3 Synthetic Resin 4 Warp Thread 5 Weft Thread 6 Chain Thread 7 Protrusion 8 Woven / Knitted Fabric with Double Structure 9 Connecting Thread 10 Cutter Knife

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Reichi Namizama 23 Uji Kozakura, Uji-city, Kyoto Unitika Ltd.In the Central Research Laboratory, Ltd. Central Research Laboratory

Claims (3)

[Claims] 1. A soil structure reinforcing material, characterized in that a synthetic resin is impregnated into a fiber sheet in which projections made of fibers having a height of 1 to 30 mm are formed and the ground structure is a lattice structure. 2. The soil structure reinforcing material according to claim 1, wherein one side of the lattice of the ground structure of the fiber sheet has a length of 10 to 100 mm. 3. A synthetic resin is impregnated into a fiber sheet having protrusions with a height of 1 to 30 mm formed by cutting a connecting yarn of a woven or knitted fabric having a double structure in which the ground structure is a lattice structure. Method for manufacturing earth structure reinforcement.