JP2003074068A - Slope stabilizing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slope stabilizing method for restraining falling-in by improving the ground by sufficiently solidifying a weak slope surface layer part, surely fixing an anchor by self-standing without collapsing a hole wall of the anchor, and surely operating pressing force of a pressure receiving plate on a slope in a state of fixing the anchor to the pressure receiving plate. SOLUTION: This slope stabilizing method fixes a head part of the anchor 7 to the pressure receiving plate 9 arranged on the slope of natural ground 1 by fixing the tip part side to the ground by driving the anchor 7 in the natural ground 1, and improves the ground of an anchor head part side pressure receiving plate arranging area by injecting an ultrafine particle consolidating material having the particle size of 6 μm or shorter into the surface layer part of the natural ground 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slope stabilizing method of solidifying a ground surface layer portion using a solidifying material for ground improvement and pressing a slope by a pressure receiving plate fixed to an anchor. In addition, a slope is a generic term for a natural slope and a cut slope. Further, the pressure receiving plate is a generic term for a structure made of concrete or steel or resin for slope stabilization which is installed on a slope including a legal frame.

[0002]

2. Description of the Related Art As one of construction methods for pressing and stabilizing a slope using a concrete structure such as a pressure receiving plate and a method frame,
A rock bolt is driven into the ground, a pressure receiving plate, etc. is attached to the head, and the head of the lock bolt is fixed to the pressure receiving plate with a nut etc. and the slope of the pressure receiving plate bottom is pressed to prevent the rock from collapsing. A slope stabilization method using the rock bolt method is used.

Similarly, as a construction method using a pressure receiving plate or the like, the ground anchor is driven into the ground, the tip side of the ground anchor is fixed to the ground, and the pressure receiving plate or the like is attached to the head of the ground anchor.
Pre-stress the ground anchor with a jack or the like to make it tight, and in this tension state, fix the ground anchor to the pressure receiving plate with a wedge etc. and press the slope with the bottom surface of this pressure receiving plate to prevent the ground from collapsing. A slope stabilization method using the ground anchor method is used.

A slope stabilizing method using such a pressure receiving plate is described in JP-A-8-199585. In the slope stabilization method described in this publication, in order to stabilize the fragile ground with a small pressure receiving plate, a protrusion is provided on the bottom surface of the pressure receiving plate to increase frictional resistance or a solidified material is injected into the surface layer of the slope to improve the ground. I am trying.

Further, Japanese Unexamined Patent Publication No. 9-100471 discloses a ground improvement injection material intended to be capable of arbitrarily adjusting the gel time and the strength of a consolidated body in combination with cement for the purpose of ground reinforcement and the like. is doing.

Further, Japanese Patent Application Laid-Open No. 11-124848 discloses a slope stabilizing method of injecting grout into the surface layer of the ground. In the slope stabilization method described in this publication, by injecting grout into the slope ground, the effect of supporting the ground by the pressure bearing member (pressure receiving plate) is improved, and the grout injection work is performed uniformly regardless of the operator. To make it easier, make a hole in the bottom plate of the bearing member,
The grout injection pipe is fitted into this hole, and the grout is pressure-fed from the hose to the grout injection pipe to inject the grout into the ground surface layer.

[0007]

However, with respect to conventional solidifying materials such as solidifying materials for ground improvement and pouring materials (grouts), the particle diameters of the material components are not taken into consideration. There is no specific description of the solidifying material or the material component of grout in the publication of No. 2, and it is considered that even if it is combined with the injection material of the publication of No. 3, sufficient penetration into soft ground cannot be obtained. In order to confirm such a point, an experiment was performed by using an actual conventional material and injecting cement milk, urethane, silica resin, or other solidifying material into humus or sandy soil that has accumulated on the surface of the natural slope. I just did
The conventional solidifying material does not sufficiently penetrate into the ground, and the ground cannot be substantially improved.

Therefore, in the conventional slope stabilization method using the pressure receiving plate using the solidifying material, the soft ground surface layer portion cannot be solidified sufficiently, and the rock bolts and ground anchors (hereinafter referred to as these) driven into the ground are not formed. Even if the tip side is fixed to the ground and the rock slope is pressed by the pressure receiving plate via this anchor, the pressure receiving plate is not reliably supported by the ground, especially at the soft surface layer. Sufficient slope stabilization effect cannot be obtained. Further, since the ground is not solidified sufficiently, the hole wall for inserting the anchor may collapse and the grout material for anchor fixing may not be injected.

[0009] That is, as a problem of the prior art: Conventional grout such as cement milk and urethane has a relatively large particle size (about 15 μm), and therefore has a strong viscosity and a low permeability to the ground. The solid formed does not grow large enough. Therefore, the supporting force by the ground surface layer portion is not sufficiently improved. Since the conventional grout material has low permeability, the solidified body may be formed only at the tip of the lock bolt or the like, and sufficient fixability cannot be obtained. Since the grout is injected after the rock bolt or the like is driven, if the surface layer portion is soft when the lock bolt is driven, the hole wall collapses and the grout is not reliably filled, which causes a problem in the performance of the rock bolt. In a ground with many voids such as a talus or a ground with cracks, the injected grout does not fill the injection part uniformly and escapes, and a good solidified body cannot be formed in the predetermined range. , The ground bearing capacity is insufficient.

The present invention has been made in consideration of the above-mentioned prior art, and the ground is improved by sufficiently solidifying the soft slope surface layer portion, and the anchor is securely fixed by making it self-supporting without breaking the hole wall of the anchor. An object of the present invention is to provide a slope stabilizing method that reliably applies the pressing force of the pressure receiving plate to the slope with the anchor fixed to the pressure receiving plate to prevent the slope from falling.

[0011]

In order to achieve the above object, in the present invention, an anchor is driven into the ground and the tip side thereof is fixed to the ground, and the head of the anchor is placed on the slope of the ground. In the slope stabilization method that is fixed to the installed pressure plate,
Provided is a slope stabilization method, which comprises improving the ground in a pressure receiving plate installation region on the anchor head side by injecting an ultrafine particle binder having a particle diameter of 6 μm or less into the surface layer portion of the ground.

According to this structure, as a solidifying material for the ground, an ultrafine particle slurry having a particle size of 6 μm or less (suspension type grout material)
Since it is used, the permeability to the ground is improved, and it penetrates into the ground surface layer stably and uniformly, and escapes the solidification material in the soft ground such as humus and sand, and in the talus layer where there are many voids and cracks. It is possible to sufficiently improve and solidify the ground at a predetermined pressure receiving plate installation position without causing it.

Further, in the present invention, a step of placing an injection pipe for injecting the solidifying material for ground improvement into the surface layer portion of the slope on the ground, and a step of injecting the solidifying material from the injection pipe, In a slope stabilizing method, which comprises a step of placing an anchor on the slope, a step of providing a pressure receiving plate on the anchor head, and a step of fixing the anchor to the pressure receiving plate and pressing the slope with the pressure receiving plate, There is provided a slope stabilizing method, wherein the consolidating material comprises an ultrafine particle grout material having a particle diameter of 6 μm or less.

According to this structure, since the ultrafine particle slurry having a particle size of 6 μm or less is used as the solidifying material for the ground, the permeability to the ground is improved, and the ground surface layer portion is stably and uniformly penetrated to form a mulch soil. It is possible to sufficiently improve and solidify the ground in the surface layer portion of a predetermined pressure receiving plate installation area without causing the solidifying material to escape in the soft ground such as sand and sand and the talus layer with many voids and cracks. As a result, the ground layer surface layer portion reliably supports the pressure receiving plate with the anchor head fixed to the pressure receiving plate, and a highly reliable slope stabilizing action by the pressure receiving plate can be obtained.

In the present invention, the pressure receiving plate collectively refers to a structure for stabilizing slopes made of concrete, steel or resin, including a method frame.

Further, the anchor of the present invention is not limited to the ground anchor construction method in which a tension force is applied to a pressure receiving plate by applying a tension force with a jack or the like, and a tension action by a fastening force of a nut or the like is used without applying a tension force. It can be applied to any of the rock bolt construction methods for fixing the anchor to the pressure receiving plate, and can also be applied to the foundation reinforcement construction method of the building.

In a preferred configuration example, before the anchor head is fixed to the pressure receiving plate, the injection pipe is fixed to the pressure receiving plate to be integrated.

According to this structure, after the solidifying material is injected into the surface layer through the injection pipe and the pressure receiving plate is attached, the injection pipe is fixed to the pressure receiving plate before the anchor head is fixed to the pressure receiving plate. Due to the integration, the surface layer ground of the portion which is improved in consolidation through the injection pipe is integrated with the pressure receiving plate, the pressure receiving plate area is substantially increased, and the slope stabilizing action is enhanced. As a result, a sufficiently large slope pressing action can be obtained without increasing the size of the pressure receiving plate itself, the surrounding environment can be maintained in a state close to nature, and the slope can be stabilized while maintaining the landscape and greening the surroundings. .

In a preferred configuration example, the solidifying material for soil improvement has ultrafine particle cement having a specific surface area of 5000 cm ² / g or more, an alkali metal silicate and water as essential components, and a solid content of 10 to 50% by weight. It is characterized by being an aqueous slurry.

The solidifying material having such a structure has a specific surface area of 50.
It is formed by mixing an aqueous slurry containing 00 cm ² / g or more of ultrafine particle cement as an essential component with an alkali metal silicate and an aqueous solution containing the essential component so that the solid content is 10 to 50% by weight. . With such a solidifying material, as described above, it is possible to sufficiently permeate into the ground and solidify the surface layer portion without fail.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 are explanatory views sequentially showing cross-sections of main parts in respective steps of the slope stabilizing method using a lock bolt according to the embodiment of the present invention. First, Fig. 1
As shown in FIG. 5, a plurality (four in this example) of steel pipes or FRP pipes or injection pipes 2 made of a resin pipe such as a vinyl chloride pipe are driven into the improved range of the ground 1 having the soft surface layer portion to be improved. In this case, hammering may be used, or it may be mounted on a rock drill and drilled while drilling.

Next, as shown in FIG. 2, the solidifying material 3 is injected from the injection pipe 2. In this example, the solidifying material 3 is a two-liquid reaction type solidifying material of the main agent A and the hardening agent B (a specific example will be described later), and the A liquid B is injected through the injection adapter 4 by the 1.5 shot method. The liquids are separately pumped, joined just before the injection, mixed, and injected into the surface layer of the natural ground 1. This binding material 3 is
It is an inorganic ultrafine particle suspension having a highly penetrating gelling property, and its particle size is 6 μm or less. When the injection pressure is high, as shown in (III), the caulking 5 of waste or urethane resin is provided in the mouth portion of the ground surface of the buried injection pipe 2.

By injecting such a solidifying material 3, the improved ground 6 is formed and the soft ground surface layer portion is solidified. In the BB cross section of (II), immediately after the solidification material 3 is injected from the fourth injection pipe 2 (left side in the figure) after the ground is improved by the solidification material from the three injection pipes 2. Shows the state of.

The method of injecting the solidifying material 3 composed of the ultrafine particle suspension is not limited to the 1.5 shot method, but may be a 1 shot method of injecting from a single injection tube depending on the fine particle material, the improvement conditions and the like. It is also possible to use a two-shot method in which two liquids are injected from separate injection pipes and mixed in the ground.

Next, as shown in FIG. 3, a lock bolt 7 made of a resin pipe such as a hollow steel pipe, an FRP pipe or a vinyl chloride pipe is driven into the improved ground 6. Drive the lock bolt 7 into the tip of the lock bolt 7 as shown in the example in the figure.
It is also possible to attach and install it while punching as it is (self-drilling method), or to punch first with a drilling rod equipped with a bit and then after pulling out the drilling rod, insert the lock bolt ( Any other perforation method) may be used.

Next, as shown in FIG. 4, the lock bolt 7
Inject a grout 20 consisting of normal cement milk or mortar. At this time, when the injection pressure of the grout 20 is large, as shown in (II), a caulking 5 of waste cloth or urethane resin is provided at the mouth portion of the ground surface of the embedded rock bolt 7.

Next, as shown in FIG. 5, a pressure receiving plate 9 having a through hole formed in the bottom plate 10 in advance at the position of the injection pipe 2 is inserted into the bottom plate 10 while the head of each injection pipe 2 is inserted. The head of the lock bolt 7 is inserted through the section and installed on the improved ground 6 of the natural ground 1.

Next, as shown in FIG. 6, the heads of the respective injection pipes 2 and the lock bolts 7 are respectively attached to the pressure receiving plates 9 by nuts.
Then, the cap 11 is covered, grease or rust preventive oil is filled, and head treatment is performed. As a result, the pressure receiving plate 9 is installed on the improved ground 6 in the surface layer portion of the natural ground 1 in a state of being combined with and integrated with the improved ground 6.

In this case, if the injection pipe 2 and the lock bolt 7 are made of the same material, the integration with the improved ground will be ensured.

In the case where the head treatment is performed, if the lock bolt head has a rust preventive coating such as surface treatment, it is only necessary to fasten the nut. If there is a possibility of rusting, attach an anticorrosion cap and apply grease. In this case, by constructing the pressure receiving plate 9, the injection pipe 2 and the lock bolt 7 by appropriately incorporating non-metallic members, there is no need to perform special treatment for rust prevention, and the structure is simplified and implemented. It is also easy to do, and deterioration due to the influence of acid rain can be suppressed.

According to the present embodiment, the soft ground surface layer portion is improved, and the improved ground and the pressure receiving plate are integrated to enhance the pressing action of the pressure receiving plate on the slope and the supporting force of the pressure receiving plate from the ground side. A stable and highly reliable slope stabilizing effect can be obtained. Further, the shape of the improved ground becomes larger than the bottom area of the pressure receiving plate, and this large improved ground exhibits the function of the pressure receiving plate. Therefore, even if the shape of the pressure receiving plate is reduced, a large slope stabilizing effect can be obtained. For this reason, it is possible to minimize the felling of plants and the like and stabilize the slope while sufficiently preserving the surrounding environment.

Even when the injection pipe and the pressure receiving plate are not integrated, as in the case where they are integrated, the hole wall protection and ground subsidence prevention when the lock bolt is driven, and the surface soil of the pressure receiving plate bottom plate are prevented. The effect of scour prevention can be obtained. If they are not integrated, the head treatment of the injection tube 2 is unnecessary. In this case, the exposed head of the injection tube may be cut.

In the above embodiment, the injection pipe 2 is first driven and then the lock bolt 7 is driven. However, the order is reversed, the lock bolt 7 is first driven, and then the injection pipe 2 is driven. May be crowded.

FIG. 7 shows another embodiment of the process of FIG. 4 described above. That is, instead of injecting the normal grout 20 through the lock bolt 7, the consolidating material made of the ultrafine particle slurry of the present invention having a particle diameter of 6 μm or less is injected as in the case of FIG. As a result, the ground of the fixing portion is improved with respect to the ground at the tip of the lock bolt 7.

This is particularly effective when the ordinary grout is injected and the grout escapes and cannot be injected into a predetermined range when the ground has many voids or cracks are generated. In such a case, if the ultrafine particle binder of the present invention is used, it has high permeability and is rapidly and uniformly gelled around the periphery, and it does not have the escape of a conventional grout material and can be reliably solidified within a predetermined range. The lock bolt 7 can be connected to improve the fixing property.

FIG. 8 shows another embodiment. In this embodiment, the injection pipe 2 is driven into a position where the bottom plate 10 of the pressure receiving plate 9 is not inserted to inject the solidifying material, and the injection pipe 2 and the pressure receiving plate 9 are injected.
An example in which and are separated is shown.

FIG. 9 shows still another embodiment. This embodiment shows an example in which only the rock bolt 7 is driven according to the geological condition without using an injection pipe, and the ultrafine particle consolidating material of the present invention is injected through the lock bolt 7. As a result, the entire ground can be improved from the surface layer on the lower surface side of the pressure receiving plate 9 to the tip of the lock bolt.

FIG. 10 shows still another embodiment. This embodiment is an example applied to the ground anchor construction method. An anchor 13 is installed on a concrete structure 12 such as a pressure receiving plate or a method frame. The anchor 13 is one in which a tensile member 15 made of PC steel or the like covered with a sheath 14 is embedded in the ground 1, and an anchor head 13a covered with a rust preventive cap 11 and a free length on which a tensile force acts. Part 13b,
It is composed of a fixing unit 13c on the ground. For example, injection pipes (not shown) on both sides of the concrete structure 12 such as a legal frame
And the ultrafine particle solidifying material of the present invention is injected from the injection pipe to form the improved ground 6 in the surface layer portion.

11A to 11C show an example of a drilling procedure by a rock drilling machine. As shown in (A), the rock drill 16
The swivel 17 is attached to the tip of the
Is attached. A bit 19 is provided at the tip of the rod 18. These are joined as shown in (B), and the natural ground 1 is perforated as shown in (C).

FIG. 12 shows an example of the particle size accumulation curve. The example in the figure shows a conventional grout material having a particle size of D50 of 15 μm. In the present invention, an ultrafine particle binder having D50 of 6 μm or less, preferably D85 of 6 μm or less is used, as used in the experiment described later.

The characteristics of the ultrafine particle solidifying material of the present invention are as follows. An injection material of an ultrafine particle suspension type (fine particles suspended and dispersed in an aqueous solution) having an average particle diameter of 4 μm. Therefore, it has high permeability. Since it is an inorganic material, it is safe with no effects on the human body or underground pollution. Limited injection can be performed by gelation of the silica aqueous solution, and breathing (separation of suspended particles due to insufficient gelation) can be suppressed. The gel time can be adjusted. The strength develops quickly. (In the experiment, gelation occurred in 2 to 3 minutes and the flow stopped, and a uniaxial compressive strength of about 3 MN / m ² was obtained in one day.) High strength. (Normal grout is 0.1-0.5
While it is kg / cm ² , the ultrafine grain grout material of the present invention is about 30 kg / cm ² . ) A solid is formed even in water.

The ultrafine particle consolidation material of the present invention having the above characteristics will be further described below. The solidifying material for solidifying the ground used in the present invention has a particle size of 500 in terms of specific surface area.
An ultrafine particle cement of 0 cm ² / g or more, an alkali metal silicate, and water are essential components, and a solid content is 10 to 50.
It is a wt% aqueous slurry.

In this case, the type of cement is not particularly limited, and various kinds of cement such as ordinary Portland cement, early-strength Portland cement, and moderate heat Portland cement can be used, and if necessary, lime, gypsum, dolomite plaster. , Fly ash, granulated blast furnace slag, and other additives can also be added. The particle diameter of these cements is not less than 5000 cm ² / g and preferably not less than 10000 cm ² / g.

The larger the specific surface area of the cement particles is, the smaller the particle diameter is, and the possibility that the cement particles permeate into the gaps of the ground sand and the cracks of the rock is improved, so that the anchor can be more firmly fixed. However, if the specific surface area is extremely large, it tends to agglomerate in the solidifying material slurry, and it is industrially disadvantageous in terms of cost.
Most preferably, it is in the range of 0000 to 15000 cm ² / g.

Next, examples of the alkali metal silicate used in the present invention include potassium silicate, sodium silicate and the like. Sodium silicate is preferable in view of industrial availability.

The solidifying material for ground improvement of the present invention contains these fine particle cement, alkali metal silicate and water as essential components and has a solid content of 10 to 50% by weight, preferably 15 to 40% by weight. Is an aqueous slurry of. If the solid content is too high, the pouring operation is difficult, and conversely, if the solid content is too low, the solidifying material itself becomes difficult to cure.

The amount of the above-mentioned fine particle cement used in the present invention is preferably as large as possible in consideration of the consolidation strength of the ground, but there is a demerit that the more it is used, the more the viscosity of the mixed solution increases. Considering the balance between strength and viscosity, the amount of cement used is preferably 100 to 500 g, more preferably 15 g, per liter of the solidifying material.
The ratio is in the range of 0 to 350 g.

The amount of the alkali metal silicate used in the present invention is such that the SiO ₂ content in the alkali metal silicate is preferably 20 to 200 g, and more preferably 60 to 130 g per liter of the solidifying material. To do. If the amount of this alkali metal silicate used is small, the flow will stop after injection,
It does not become a clear gel and tends to flow out to spring water. On the other hand, when the amount of the alkali metal silicate used is large and exceeds 200 g, the solid content increases and it becomes difficult to disperse the cement.
Even if it exceeds 130 g, it is industrially disadvantageous from the viewpoint of cost.

The alkali metal silicate used in the present invention is
The molar ratio in the alkali metal silicate (SiO ₂ / M ₂ O:
However, M represents an alkali metal atom), but 2.0 to 4.0.
It is preferable that the range is from the viewpoint of the flow stop time of the solidifying material. That is, the solidifying material of the present invention is injected into the ground surface layer through a hollow injection pipe and penetrates into the ground cracks and sandy ground, but if the flow stop time is too short, the solidifying material May stop flowing before it sufficiently penetrates, and the effect of the present invention may be insufficient. In addition, even when the flow stop time is extremely long, the effect range of the injection material becomes unclear, and it may not be possible to solidify the ground in an appropriate area. In the present invention, the gel time can be adjusted by adjusting the component ratio of the alkali metal silicate.

That is, in the solidifying material of the present invention, the flow stop time is more appropriate by setting the ratio of SiO ₂ content in the alkali metal silicate and the molar ratio in the alkali metal silicate within a specific range. In addition, when the flow stops, a clear gel body is formed, and even when there is spring water from the natural ground, the surface layer of the ground can be solidified accurately without flowing the solidifying material.

Within this specific range, the molar ratio (SiO ₂ / M ₂ O: where M is an alkali metal atom) in the alkali metal silicate is x, and the alkali metal silicate in 1 liter of the binder is Where y is the ratio of SiO _{2 of} the following formulas, (1) to (5), (1) y ≦ 200 (2) x ≧ 2.4 (3) x ≦ 4.0 (4) y ≧ 120x -260 (however, 2.4 ≦ x ≦
3.0) (5) It is a range that satisfies the relationship represented by y ≧ 100 (however, 3.0 ≦ x ≦ 4.0). More preferably, in addition to the above formulas (1) to (5), the following formulas (6) and (7), (6) y ≧ 120x−230 (2.4 ≦ x ≦ 3.
0) (7) y ≧ −10x + 160 (3.0 ≦ x ≦ 4.
It is a range that also satisfies the relationship represented by 0).

The solidifying material of the present invention contains, as other components, extenders such as bentonite and fly ash to the extent that the solidifying performance is not impaired, calcium scavengers such as sodium citrate and sodium tartrate, or gelling control agents. A modifier such as an AE agent or a water reducing material, or an additive such as a foaming agent such as aluminum powder can be added.

Next, the method for producing the consolidated material of the present invention will be specifically described.

The method for producing a consolidated material of the present invention has a specific surface area of 5
Liquid I, which is an aqueous slurry containing 000 cm ² / g or more of ultrafine particle cement as an essential component, and liquid II, which is an aqueous solution containing an alkali metal silicate as an essential component, have a solid content of 1
It is mixed so as to be within 0 to 50% by weight.

In the solidifying material obtained by the above method, the reaction immediately starts when the cement component and the alkali metal silicate component are mixed and the flow stops, so that the cement component and the alkali metal silicate component are mixed. Immediately afterwards, it is necessary to inject. Here, after mixing the cement component and the alkali metal silicate component, water is added to make an aqueous slurry, or either component is made an aqueous slurry or water-soluble and then other components are mixed to further add water. When adjusting the solid content by adding, it takes time to homogenize to the extent that there is no practical problem, and if injection is performed in such a time-consuming state, flow will stop while it does not sufficiently penetrate. Will be lost. Therefore, in the method of the present invention, the mixture of the liquid I, which is an aqueous slurry containing the above ultrafine particle cement as an essential component, and the liquid II, which is an aqueous solution containing an alkali metal silicate as an essential component, has a solid content of 10%. Mix so as to be in the range of 50% by weight. Here, the reason for limiting the solid content is as described above for the solidifying material.

In the method for producing a consolidated material of the present invention, the method of mixing the liquid I and the liquid II is not particularly limited, but, for example, when mixing and pouring the pouring material by a normal ground pouring method or the like. It is preferable to use the one-shot method, the 1.5-shot method, the two-shot method, etc. used for the above because the time loss is small and it can be used for the injection immediately after the production.

In the one-shot method, for example, the liquid I and the liquid II are combined and mixed by a grout mixer or the like to form a solidifying material, and the solidifying material is sucked from the inlet of the grout pump and injected from the outlet of the grout pump. It is a method of discharging into a pipe.

In the 1.5-shot method, the aqueous slurry of the liquid I and the aqueous solution of the liquid II are adjusted with a grout mixer or the like, and the liquid I is discharged from each suction port of a grout pump having two suction ports and two discharge ports. This is a method in which the aqueous slurry and the aqueous solution of the liquid II are respectively discharged to a Y-shaped injection adapter, mixed at the Y-shaped portion to form a solidifying material, and then injected into an injection pipe.

The two-shot method is carried out by using an aqueous slurry of liquid I, I
The aqueous solution of the liquid I is adjusted with a grout mixer or the like, and the aqueous slurry of the liquid I and the aqueous solution of the liquid II are respectively sucked from each of the suction ports of the grout pump having two suction ports and two discharge ports. This is a method in which an aqueous slurry of liquid I and an aqueous solution of liquid II are discharged from a discharge outlet into a double hollow injection pipe, and these are mixed at a discharge portion of the double hollow injection pipe to form a solidifying material and then injected.

In order to confirm the effect of the solidified body composed of the ultrafine particle slurry used in the present invention, an experiment was conducted in comparison with a conventional material. Experiments are as shown in Tables 1 and 2 below.
Thirteen rods from o.1 to No.13 were buried in the ground and each was injected with a chemical solution to give a test body, which was cured for 2 days, and then the test body was dug up to compare the states. The ground was fine sand, the rod length was 3 m, and the drilling angle was about 5 ° upward.

[0061]

[Table 1]

[0062]

[Table 2]

No. 1, No. 4, No. 7 and No. 10 to No. 13 are examples of the present invention, and the chemical liquid (injection material) is a two-liquid reaction type ultrafine particle grout material, and gel time Is 3 minutes.

As comparative examples to this, No. 2 and No. 3
Is a comparative example (a) using a conventional cement milk injection material, No. 5 and No. 6 are comparative examples using a conventional urethane injection material (b), and No. 8 and No. 9 are conventional 5 is a comparative example (C) using the silica resin-based injection material of FIG.

13 to 16 show the dug-up state of the test body. FIG. 13 is a test body of an example (No. 4) of the present invention, FIG. 14 is a test body of a comparative example (a) (No. 2), FIG.
5 shows the test piece of the comparative example (b) (No. 5), and FIG. 16 shows the dug-up state of the test piece of the comparative example (c) (No. 8). The other test bodies also had substantially the same shape according to each type.

As can be seen from the respective figures showing the experimental results, the embodiment of the present invention is, as compared with the comparative example, sufficiently permeated into the surrounding ground to be solidified and integrated to bulge in a large volume, and as an improved ground injection material. It was confirmed to be effective.

[0067]

As described above, in the present invention, since the ultrafine particle slurry having a particle size of 6 μm or less is used as the solidifying material for the ground, the permeability to the ground is improved, and the ground is stably, uniformly and rapidly. Sufficiently improve the ground of the surface layer of the specified pressure receiving plate installation area without penetrating the solidifying material in the soft ground such as mulch and sand and the talus layer with many voids and cracks. Can be solidified.
As a result, the ground layer surface layer portion reliably supports the pressure receiving plate with the anchor head fixed to the pressure receiving plate, and a highly reliable slope stabilizing action by the pressure receiving plate can be obtained.

When the anchor is driven into the natural ground, the hole wall of the anchor is strongly protected, the collapse of the hole wall is suppressed, and the self-supporting function of the hole wall is enhanced. Therefore, grout injection for anchor fixation can be reliably performed, a highly reliable anchor function can be obtained, and the slope stabilizing effect can be enhanced.

When tension is applied to the anchor,
Since the surface layer ground is firmly solidified, the pressure receiving plate is less likely to bite into the ground and be buried therein, and the anchor can be provided with necessary tension as designed and the slope can be reliably stabilized.

Further, by integrating the surface ground and the pressure receiving plate in the portion improved by the injection of the ultrafine particle consolidating material, the pressure receiving plate area is substantially increased and the slope stabilizing action is enhanced. As a result, since the improved ground can be used as a pressure receiving plate, the pressure receiving plate shape made of steel, resin, concrete or a mixture thereof can be made small, and a sufficiently large slope pressing action can be achieved without increasing the size of the pressure receiving plate itself. can get.

As described above, the pressure receiving plate itself can be miniaturized, and even if the slope surface layer portion is soft ground such as humus or sandy soil, the slope can be sufficiently stabilized, so that natural wood or the like can be cut without cutting. While maintaining the environment close to nature, it is possible to stabilize the slope while maintaining the landscape and greening the surrounding area.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first step of an enforcement procedure of the present invention.

FIG. 2 is an explanatory view of the next step of FIG.

FIG. 3 is an explanatory diagram of the next step of FIG. 2.

FIG. 4 is an explanatory view of the next step of FIG.

FIG. 5 is an explanatory view of the next step of FIG.

FIG. 6 is an explanatory diagram of the next step of FIG. 5;

FIG. 7 is an explanatory view of another embodiment of the enforcement method of the present invention.

FIG. 8 is an explanatory view of another embodiment of the enforcement method of the present invention.

FIG. 9 is an explanatory diagram of another embodiment of the enforcement method of the present invention.

FIG. 10 is an explanatory diagram of another embodiment of the enforcement method of the present invention.

FIG. 11 is an explanatory view of a drilling procedure by a rock drill.

FIG. 12 is a graph of a particle size accumulation curve of a cement material.

FIG. 13 is a shape diagram of an experimental test body according to an example of the present invention.

FIG. 14 is a shape diagram of a test body of a comparative example of the experiment.

FIG. 15 is a test piece shape diagram of another comparative example of the experiment.

FIG. 16 is a shape diagram of a test body of another comparative example of the experiment.

[Explanation of symbols]

1: Ground, 2: Injection pipe, 3: Solid material, 4: Injection adapter, 5: Caulking, 6: Improved ground, 7: Rock bolt, 8: Bit, 9: Pressure plate, 10: Bottom plate, 11: Cap, 12: concrete structure, 13: anchor, 1
3a: Anchor head, 13b: Free length part, 13c: Anchoring part, 14: Sheath, 15: Tensile material, 16: Rock drill, 1
7: Swivel, 18: Rod, 19: Bit, 20: Normal grout.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) E02D 3/12 101 E02D 3/12 101 5/80 5/80 Z // C04B 111: 70 C04B 111: 70 F term ( Reference) 2D040 AA00 AB01 AC02 AC05 BB03 CA01 CA03 CA10 CB03 CC01 CD06 CD09 DB01 DC01 2D041 GA01 GB01 GC12 GC14 GD02 2D044 DC04 EA01 4G012 PB06

Claims (4)

[Claims] 1. A slope stabilizing method for driving an anchor into the ground, fixing the tip end side of the anchor to the ground, and fixing the head of the anchor to a pressure receiving plate installed on the slope of the ground. A method for stabilizing slopes, characterized by improving the ground in the pressure receiving plate installation region on the anchor head side by injecting ultrafine particle solidifying material having a particle size of 6 μm or less into the surface layer of the mountain. 2. A step of placing an injection pipe for injecting a solidifying material for ground improvement into a surface layer portion of a slope on the ground, a step of injecting a solidifying material from the injection pipe, and In the slope stabilization method, which comprises a step of driving an anchor, a step of providing a pressure receiving plate on the head of the anchor, and a step of fixing the anchor to the pressure receiving plate and pressing a slope with the pressure receiving plate, The slope stabilizing method is characterized in that the material is an ultrafine grain grout material having a particle diameter of 6 μm or less. 3. The slope stabilizing method according to claim 2, wherein the injection pipe is fixed to and integrated with the pressure receiving plate before the anchor is fixed. 4. The specific material has a specific surface area of 50.
2. An aqueous slurry having an ultrafine particle cement of 00 cm ² / g or more, an alkali metal silicate and water as essential components and having a solid content of 10 to 50% by weight.
The slope stabilization method according to 2 or 3.