KR101147160B1 - Slope protection method by high durable and permeable concrete - Google Patents

Abstract

The present invention relates to slope protection methods such as slopes of roads, freshwater slopes such as dams or reservoirs, slopes of alternating portions, slopes of active sites, and slopes of steep slopes that are in danger of collapse, such as slopes of roads created by the Open Cut method. It is about.
Slope protection method using a highly durable permeable concrete according to the present invention is a formulation for mixing the permeable concrete, including cement, 2 ~ 13mm aggregate, water-soluble inorganic admixture containing alkali metal ions and halogen ions, short fibers, water Stage 1; A second step of blending permeable concrete by bringing each material according to the blending design into the attaching machine; And a third step of attaching the blended water-permeable concrete to the slope while spraying the pneumatic concrete.

Description

Slope protection method by high durable and permeable concrete

The present invention relates to slope protection methods such as slopes of roads, freshwater slopes such as dams or reservoirs, alternate slopes, slopes of active sites, slopes in contact with various facilities, or slopes of steep slopes that may collapse. It is about.

If the slope is left as it is, there is a risk that the topsoil and the like are eroded and collapsed by the runoff of rainwater and groundwater. The slope protection work is done to prevent the risk of collapse, and the existing slope protection method is a hermetic protection method for attaching mortar or concrete, a vegetation material installation method for installing vegetation base materials, and a vegetation mat method for installing vegetation mats. There is an open protection method such as

In the case of the closed slope protection method, groundwater invades from the mounted rear surface or surface water invades into the cracked area, which leads to ground erosion, cavitation, dropping, and collapse. In addition, residual pore water pressure is generated on slopes with high groundwater levels such as freshwater slopes and slopes, and surface collapse of the ground is likely to occur.

In the case of the open slope protection method, the ground is eroded, fallen off, and collapsed by groundwater intrusion and surface water invasion at vegetation defects. It is also difficult to apply to slopes with high groundwater levels, such as freshwater slopes and slopes.

Recently, a slope protection method by on-site casting permeable concrete, which combines a closed slope protection method and an open slope protection method, has been developed and applied. However, in case of the slope protection method by in-situ concrete, it takes time to mix, place, and voltage, and the thin film binder is dried on each aggregate so that the adhesive strength cannot be expressed and the quality deterioration occurs. have.

The present invention has been developed in order to improve the problem of the slope protection method by the conventional cast-in-place concrete permeable concrete has the following technical problems.

First, it is intended to provide a slope protection method by on-site casting permeable concrete that has excellent durability and strength, toughness, chemical resistance, and ease of construction.

Second, we want to provide a slope protection method that can be flexibly applied to small sites as well as large sites.

Third, it is intended to provide a slope protection method that can be applied stably to the steep slope slope.

In order to solve the above technical problem, the present invention, the first step of mixing the permeable concrete, including cement, 2 ~ 13mm aggregate, water-soluble inorganic admixture containing alkali metal ions and halogen ions, short fibers, water; A second step of blending permeable concrete by bringing each material according to the blending design into the attaching machine; And a third step of attaching the blended permeable concrete to the slope while spraying the pneumatic concrete, thereby providing a slope protection method using the highly durable permeable concrete.

According to the present invention, the following effects can be expected.

First, because of the use of permeable concrete, the ground of the rear surface is not eroded, and accordingly, maintenance is more advantageous than the conventional hermetic protection method.

Second, because the use of permeable concrete, which is advantageous in strength and fluidity while using less unit cement and unit quantity, slope protection can be carried out economically and constructively.

Third, it can be installed as a slope protector having a form of a void having a diameter of about 1mm and a continuous void of about 15% or more, so that the greening through vegetation can be easily implemented on the slope.

1 to 3 illustrate a blending method of permeable concrete in a slope protection method according to the present invention.
Figure 4 shows the construction cross-sectional view of the embodiment to which the wire mesh frame in the slope protection method according to the present invention.
5 shows a basic wire mesh frame and a construction state thereof.
6 shows a cross-shaped wire mesh frame and a construction state thereof.
7 shows a circular wire mesh frame and a construction state thereof.

1. High durability evaluation of permeable concrete

The present invention has a technical feature of using a water-permeable concrete, including cement, 2-13 mm aggregate, water-soluble inorganic admixture containing alkali metal ions and halogen ions, short fibers, water.

As the water-soluble inorganic admixture containing alkali metal ions and halogen ions is added, the density of free electrons is increased by a large amount of ions, and the ionization reaction of inorganic components such as calcium silicate or silica will be activated. Solidification and hardening are promoted to form an airtight tissue structure, resulting in excellent water and air barrier properties and stable hydrated crystallized concrete. In addition, in this process, the formation of hydrates having low resistance to chemicals (3CaO? Al ₂ O ₃ ? CaSO ₄ ? 12H ₂ O) is suppressed and the inert Friedel salt (3CaO? Al ₂ O ₃ ? CaCl _{4) having} chemical resistance is suppressed. Production of 10H ₂ O) is accelerated.

Considering the above effects, the water-soluble inorganic admixture is preferably a water-soluble material containing calcium chloride, potassium chloride, ferric chloride, magnesium oxide, ferrous lactate, sodium chloride, magnesium chloride, and ammonium chloride. The present invention proposes a "FC agent" product produced by the Japan Institute of Global Environmental Technology. [Table 1] below is the basic information on the 'FC-3000' product of the Japan Institute of Global Environmental Technology, Inc. used in the embodiment of the present invention.

Characteristics of Water-soluble Inorganic Admixture 'FC Agent' product name FC-3000 Manufacturer Global Environmental Technology Research Institute Kind of product Inorganic Compound Complex Reactant Ingredients Calcium chloride, potassium chloride, ferric chloride, magnesium oxide, ferrous lactate, sodium chloride, magnesium chloride, other (alkali metals), ammonium chloride, fresh water physical
ㆍ chemical property State: Liquid Freezing Point: -5 ℃ Boiling Point: 100 ℃ pH: 4.3 Specific gravity: 1.4 Volatile: None Product Features Flash Point: None Ignition Point: None Explosion limit (upper, lower limit): None Color: brown or cyan Odor: Odorless

When the 'FC agent' in the [Table 1] is used as a water-soluble inorganic admixture, the permeable concrete is cement 200 ~ 300kg / ㎥, aggregate 1,500 ~ 2,000kg / ㎥, 'FC-3000' 5 ~ 10ℓ / ㎥, short fiber 1.5 When mixing 2.5kg / ㎥, water 60 ~ 120ℓ / ㎥, water and water-soluble inorganic admixture as combination water, the combination water binder ratio should be 30-40%. Such compounding is to improve the durability while ensuring the permeability of the permeable concrete.

On the other hand, in permeable concrete formulation, cement adopts blast furnace cement or fly ash cement to suppress the deterioration of strength due to whitening of cement, and short fiber connects aggregate to each other to prevent cracking, and to prevent dynamic breakdown and flexural toughness. It is appropriate to employ vinylon or polypropylene-based fibers for mixing to improve. In addition, it is possible to further add particulate organic admixtures such as blast furnace slag powder, silica fume, and fly ash for the purpose of densification of concrete in the permeable concrete mixture. Furthermore, organic admixtures such as high performance AE reducing agent can be added to increase the strength and viscosity. Of course. 1 ~ 50kg / ㎥ is suitable for organic admixtures, 1.0 ~ 2.0kg / ㎥ is suitable for high performance AE water reducing agent.

Example 1 Evaluation of Properties of Cement Paste According to the Addition of 'FC Agent'

After mixing the cement paste in the formulation as shown in Table 2, the physical properties of the cement paste were examined, and the results were as shown in Table 3 below. In the formulation of Table 2, 'FC' is the product 'FC-3000' of [Table 1].

Cement paste formulation division Cement (C, kg) FC agent (B, ℓ) Water (W, ℓ) [B + W] / C (%) A 250 6.25 93.75 40 B 250 3.23 96.77 40 C 250 - 100.00 40

Cement Paste Properties division 24 days compressive strength (g / cm3) Flow (mm) A 42.0 240 B 33.8 205 C 27.8 202.5

As shown in Table 3, it can be seen that the strength and flow of the cement paste are improved by the addition of the 'FC agent'. However, the strength was increased in proportion to the amount of 'FC' added, while the flow was significantly improved in the A blended compared to B's formulation. Considering the viscosity improvement effect of 'FC' added, 'FC' is 5ℓ / ㎥ It will be preferable to add more.

Example 2 Evaluation of Properties of Concrete According to the Addition of 'FC Agent'

After mixing the concrete in the formulation as shown in [Table 4], the physical properties of the concrete were investigated, and the results were as shown in the following [Table 5]. In the formulation of Table 4, 'FC' is the product 'FC-3000' of [Table 1].

Concrete mix Name of material A B C D E F G Common Portland Cement (kg) ○ ○ ○ ○ ○ ○ ○ FC system (ℓ) ○ ○ ○ ○ ○ ○ ○ Water (ℓ) ○ ○ ○ ○ ○ ○ ○ Fly Ash (2 Types, kg) - ○ ○ ○ ○ ○ - Blast furnace slag powder
(# 4000Type, kg) - - ○ - - - - Silica fume (kg) - - - ○ - - - High performance AE water reducer (kg) - - ○ ○ ○ ○ ○ Aggregate (No. 7 crushed stone) (○) (○) (○) (○) (○) (○) (○)

Concrete properties division FC agent addition FC additive-free 28 days compressive strength
(N / mm2) Unit volume weight
(g / cm3) pH Flow
(mm) 28 days compressive strength
(N / mm2) Unit volume weight
(g / cm3) A 34.6 1.97 9.4 200 9.3 1.75 B 33.9 1.84 9.3 220 7.2 1.78 C 40.8 1.90 9.4 250 9.4 1.73 D 38.3 1.85 9.1 205 11.3 1.73 E 24.1 1.40 9.0 230 7.4 1.77 F 29.5 1.84 9.7 180 10.5 1.72 G 051.1 1.98 9.5 250 14.0 1.93

As shown in [Table 5] it can be seen that the strength and unit volume weight of the concrete is improved by the addition of the 'FC agent'. In addition, considering that the pH of concrete or water-permeable concrete is strong alkalinity of 13 or more, it can be said that the pH of concrete is represented by low alkali of 10 or less by the addition of 'FC agent'. When the pH of the concrete is lowered, it is advantageous for plant growth, so eco-friendly concrete will be realized by the addition of 'FC'.

2. Slope protection method

1 to 3 show the mixing method of permeable concrete in the slope protection method according to the invention, Figure 4 shows a construction cross-sectional view of the embodiment to which the wire mesh frame in the slope protection method according to the present invention, Figure 5 To Figure 7 shows a variety of wire mesh frame and its construction state. With reference to these drawings looks at step by step protection method according to the invention.

(1) Phase 1-Permeable Concrete Mixing Design

It is the step of mixing and designing permeable concrete suitable for slope protection including cement, 2 ~ 13mm aggregate, water-soluble inorganic admixture containing alkali metal ion and halogen ion, short fiber, water. Aggregate is prepared at a constant surface yield in the range of 2-3%. As described above, when 'FC-3000' is used as a water-soluble inorganic admixture, cement 200 ~ 300kg / ㎥, aggregate 1,500 ~ 2,000kg / ㎥, 'FC-3000' 5 ~ 10ℓ / ㎥, short fiber 1.5 ~ 2.5 It is preferable to mix and design the combination water binder ratio of 30 to 40% when mixing water of kg / m <3>, 60-120 l / m <3> of water, and water and a water-soluble inorganic admixture as a combination water. It may also be designed to include a 1-50kg / ㎥ of particulate organic admixtures or 1.0 ~ 2.0kg / ㎥ of a high performance AE reducing agent.

(2) 2nd step-permeable concrete

It is a step of mixing permeable concrete by bringing each material according to the mixing design into the attaching machine. In the present invention, it is proposed by dividing into two types according to the timing of the liquid material such as water and a mixture (water-soluble inorganic admixture, high-performance AE reducing agent).

FIG. 1 shows a method of directly injecting a liquid phase material into a body C1 of a mounting apparatus and blending the same. As shown, the primary mixture mixed with aggregate and cement is brought into the field as ready-mixed concrete (A1), and the primary mixture is poured into the hopper (A2) once in accordance with the movement of the belt conveyor (A3), and the belt The amount of the first mixture of the pour placed on the conveyor (A3) is measured with a meter (A4), and the single fiber and the particulate organic admixture (eg , Blast furnace slag fine powder, etc.) is added, and if necessary, additional cement is added to the mounting body C1. The materials introduced from the applicator body C1 are mixed, and liquid materials such as water and a mixing agent of a single pouring amount are added and mixed. The mixed material is pressurized by the air pressure supplied from the air compressor (B1) through the air hose (B2) to the nozzle (C3) through the discharge hose (C2) from the mounting body (C1) and mounted on the construction slope (S). Just do it. Such a method according to FIG. 1 can be advantageously applied at a transportation distance of about 100m and a height difference of about 30m.

2 shows a method of injecting and mixing a liquid phase material into the discharging hose C2 of the attaching machine. Overall, the method is the same as that of FIG. 1, except that an ejection ring C4 is further provided at the distal end of the discharge hose C2 of the applicator, so that the liquid material is not directly introduced into the applicator body C1, but through the ejection ring C4. There is a difference in that it is injected into the discharge hose C2. Accordingly, in the main body C1, solid materials such as cement, aggregate, short fiber, and particulate organic admixture are mixed, and the mixed material is discharged by air pressure supplied from the air compressor B1 through the air hose B2. It is pressurized to the tip of the hose C2, and a liquid material such as water and a mixture is introduced and mixed at the tip of the discharge hose C2. The liquid phase material may be mixed at a predetermined mixing ratio in advance and stored in the water tank D1. The liquid material may be introduced into the discharging hose C2 of the applicator while measuring the amount of pouring once by the flow meter D2. In some cases, cement (D3) may be further mixed with the liquid phase material which is directly injected into the discharging hose (C2) of the mounting device. It is possible to press the discharge hose (C2) of the mounting device through the tip. The material mixed at the distal end of the discharge hose C2 of the attaching machine may be pressurized by air pressure to the nozzle C3, and may be mounted on the construction slope S by air pressure. Such a method according to Figure 2 can be advantageously applied to a transport distance of about 180m, height difference of about 50m.

FIG. 3 shows a method for injecting a liquid phase material into the distal end of the discharge hose C2 of the attaching machine used when blending according to the method of FIG. 2. As shown, the distal end of the discharge hose C2 is surrounded by the spout ring C4, so that the discharge hose C2 and the spout ring C4 communicate with each other by the spout hole C2-4. When the liquid phase material is processed to be injected into the spray ring C4 by using the attaching device, the liquid phase material is mixed while being ejected to the primary mixture which is pumped to the discharge hose C2 through the ejection hole C2-4. In particular, in Fig. 3, two ejection rings C4 are provided at predetermined intervals, and the Y-shaped feed hoses D6 are connected to the respective ejection rings C2 so that the ejection mixing of the liquid phase material is repeated twice.

(3) Step 3-Mounting the pitcher concrete

It is a step of attaching the blended water-permeable concrete 30 to the slope while spraying at pneumatic pressure. It is preferable that the nozzle angle for discharging the permeable concrete 30 is slightly higher (about 10 °) than the perpendicular to the construction slope, and the discharge pressure at the tip of the nozzle is 0.2N / mm 2 or less, and the pressure of the mounting machine is The pressure is adjusted to 0.5 to 0.6 N / mm 2, and the pressure of the air compressor sent to the mounting device is about 0.7 N / mm 2. In addition, when the feeding distance is longer than 60m, fine adjustment is performed by raising the pressure of the mounting machine and the air compressor so that the discharge pressure at the nozzle tip does not change.

When the slope of the construction slope is urgent than 55 °, in order to secure the mounting thickness of the permeable concrete 30, the wire mesh frame 20 is fixed to the slope surface S, and then, the thickness of the wire mesh frame 20 is buried. It is preferable to mount the permeable concrete 30. 4 is a construction cross-sectional view when the wire mesh frame 20 is fixedly installed, and FIGS. 5 to 7 show various types of wire mesh frame 20 and a construction state thereof. As shown in FIG. 4, since the wire mesh frame 20 is fixed to the slope with the anchor 10, the pitching concrete 30 can be mounted while restraining the wire mesh frame 20, so that the thickness of the pitcher concrete 30 can be set. Is secured to the height of the wire mesh frame 20. Mounting of the permeable concrete 30 is upward from the bottom of the slope (S) toward the top.

5 shows a basic wire mesh frame and its construction state, and as shown, the basic wire mesh frame may be fixedly installed on a slope in parallel. Figure 6 shows the cross-shaped wire mesh frame and its construction state, the cross-shaped wire mesh frame is a plurality of wire meshes 21 rotatably assembled around the rotation axis 22 in the center, such a cross-shaped wire mesh frame is a rotating shaft (22 What is necessary is just to fix it to the inclined surface S, adjusting the installation direction of a wire mesh suitably. Figure 7 shows a circular wire mesh frame and its construction state, the circular wire mesh frame is assembled by connecting a plurality of wire mesh 21 by the binding ring 23 in a circular shape, such a circular wire mesh frame is appropriately circular arc with each wire mesh The anchor 10 is inserted into the binding ring 23 while drawing the fixed to the slope (S). Wire mesh frame 20 can be installed while connecting with each other by a binding line or the like.

(4) The fourth step- Cement paste  sparge

The cement paste is sprayed onto the surface of the permeable concrete. By performing this step, it is possible to prevent the aggregate from peeling off or dropping off the mounting surface of the permeable concrete. This step may be carried out by conveying the cement paste mixed in the grout mixer to the tip of the nozzle with a grout pump and mixing and spraying air therein.

Water-soluble inorganic admixtures, organic admixtures, and short fibers may also be added to the cement paste in this step, and may be blended. In this case, blending may be appropriate to omit aggregate in the permeable concrete blending design of the first step. For example, cement 200 ~ 300kg / ㎥, 'FC-3000' 5 ~ 10ℓ / ㎥, short fiber 1.5 ~ 2.5kg / ㎥, water 60 ~ 120ℓ / ㎥, combination water binder ratio 30-40%. In this case, this step can be carried out while dedicating the mounting device of FIG. The spreading amount per 1 m 2 of the cement paste is appropriately determined in consideration of the mounting thickness of the permeable concrete. For example, when the mounting thickness of the permeable concrete is 10 cm, 0.5 l per m 2 is appropriate.

A1: ready-mixed concrete A2: hopper
A3, A5: Belt Conveyor A4: Meter
B1: Air Compressor B2: Air Hose
C: mounting body C2: discharge hose
C3: nozzle C4: ejection ring
C2-4: blowout
D1: water tank D2: flow meter
D3: Cement D4: Grout Mixer
D5: grout pump D6: transfer hose
S: slope
10: anchor
20: wire mesh frame 21: wire mesh
22: shaft 23: binding ring
30: Pitcher Concrete

Claims (12)

A first step of mixing and designing the water-permeable concrete 30 containing cement, 2 to 13 mm aggregate, a water-soluble inorganic admixture containing alkali metal ions and halogen ions, short fibers, and water;
A second step of blending the permeable concrete 30 by bringing each material according to the blending design into the attaching machine;
Including the third step of mounting on the inclined surface (S) while spraying the blended water-permeable concrete (30) at pneumatic pressure,
In the third step,
A third step of fixing the wire mesh frame 20 manufactured to a predetermined height on a slope;
3B step of mounting the permeable concrete 30 to the thickness of embedding the wire mesh frame 20; Slope protection method using a high durability permeable concrete, characterized in that consisting of. In claim 1,
In the first step,
A high-durability water-permeable concrete protection process comprising the use of a water-soluble inorganic admixture containing calcium chloride, potassium chloride, ferric chloride, magnesium oxide, ferrous lactate, sodium chloride, magnesium chloride, and ammonium chloride. In claim 2,
In the first step,
Use 'FC-3000' of Japan's Global Environmental Technology Research Institute as a water-soluble inorganic admixture, but cement 200 ~ 300kg / ㎥, aggregate 1,500 ~ 2,000kg / ㎥, 'FC-3000' 5 ~ 10ℓ / ㎥, short fiber 1.5 ~ 2.5kg / ㎥, 60 ~ 120ℓ / ㎥ of water, when mixing water and water-soluble inorganic admixture as combination water Slope protection method. 4. The method of claim 3,
In the first step,
1 ~ 50kg / ㎥ of the organic admixture or 1.0 ~ 2.0kg / ㎥ made of a high performance AE reducing agent further comprises, wherein the organic admixture is a highly durable pitcher characterized in that at least one selected from blast furnace slag powder, silica fume, fly ash Slope protection method by concrete. The method according to any one of claims 1 to 4,
The second step comprises:
Step 2A for first mixing the cement, aggregate, short fibers;
Step 2B of introducing the primary mixture into the attaching machine main body (C1), and adding the water and a water-soluble inorganic admixture at the tip of the attaching machine main body (C1) or the discharge hose (C2) of the attaching machine for the second mixing; Lose,
The third step is a slope protection method using a high durability permeable concrete, characterized in that the spraying the secondary mixture of the second step in the air pressure of 0.5 ~ 1.0N / ㎜. The method of claim 5,
In step 2B,
The discharge ring C4 is surrounded by the discharge ring C4 and the discharge hose C2 and the discharge ring C4 communicate with each other by the blowing hole C2-4. And pumped into the discharge hose (C2) through the injection hole (C2-4) by injecting a combination water mixed with water and a water-soluble inorganic admixture into the discharge ring (C4). Slope protection method by high durability permeable concrete to be made. The method of claim 5,
The second step comprises:
A second mixing step of mixing cement, aggregate, and short fibers in a primary manner, but mixing only a part of cement in a blended design amount;
Blowing ring (C4) is surrounded by the discharge hose (C2) tip and the discharge hose (C2) and the blowing ring (C4) using a mounting device provided to communicate by the blowing hole (C2-4), but the primary mixture After conveying to the main body C1, it is pressurized to the discharge hose C2 by air pressure, and the cement paste in which the remaining cement and water and the water-soluble inorganic admixture are mixed is injected into the ejection ring C4, through the ejection hole C2-4. The second step of mixing the discharge hose (C2) in the discharge hose (C2) of the mounting machine while blowing to the discharge hose (C2);
The third step is a slope protection method using a high durability permeable concrete, characterized in that the spraying the secondary mixture of the second step in the air pressure of 0.5 ~ 1.0N / ㎜. delete The method according to any one of claims 1 to 4,
The wire mesh frame 20 of step 3A is a rotary cross-shaped wire mesh frame in which a plurality of wire meshes 21 are cross-assembled around a rotation shaft 22 in the center,
Step 3A is a slope protection method using a high durability permeable concrete, characterized in that the rotating cross-shaped wire mesh frame is anchored to the slope (S) with an anchor (10). The method according to any one of claims 1 to 4,
The wire mesh frame 20 of step 3A is a circular wire mesh frame assembled by connecting a plurality of wire mesh 21 with a binding ring 23 in a circular shape,
Step 3A is a slope protection method using high durability permeable concrete, characterized in that the circular wire mesh frame is anchored to the slope (S) with an anchor (30). The method according to any one of claims 1 to 4,
After the third step,
A fourth step of spraying the cement paste onto the surface on which the permeable concrete 30 is mounted;
Slope protection method by high durability permeable concrete, characterized in that further comprises a. In claim 11,
The cement paste of the fourth step,
Slope protection method using a highly durable water-permeable concrete, characterized in that the water-soluble inorganic admixture used in the water-permeable concrete is mixed.

Images