JP2860716B2 - Grout injection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to grout fillers.

[0002]

2. Description of the Related Art Various grout fillers have been used for improving the ground. Most of them are currently water glass or cement based.

[0003] Looking back on the history of grouting agents in Japan, in the 1960s, Higuchi proposed an unstable water glass grout (LW) with a short gel time combining a cement suspension and a diluted water glass solution. With improvements,
An unstable water glass grout (C-LW), which is a combination of a blast furnace colloid cement of fine particles and a low molar ratio water glass diluting solution, has a gel time of more than ten times, and has a high strength and high durability.
Furthermore, grout (MS) having a relatively long gel time based on a change in the mixing ratio of granulated blast furnace slag and Portland cement and combination with a water glass dilute solution at each molar ratio is based.

At present, for the purpose of infiltration, there are many solution types in which water glass and a curing agent are combined.

However, a suspension type or a semi-suspension type is also widely used because it is effective for obtaining high strength.

[0006]

When an alkali is added to a compound containing calcium, such as granulated blast furnace slag, hydrolysis occurs, and the latent hydraulic property of the granulated blast furnace slag is developed. However, in this case, when the slag particles come into contact with an alkaline solution, SiO ₂ and Al ₂ O ₃ in the slag elute, and then Ca ²⁺ ions elute, thereby causing the calcium silicate water to adhere to the slag particle surface. A hydrate is formed, causing the slag particles to cohere. However, the addition of alkali is required,
Unreacted alkali remains in the ground, and there is a risk of soil contamination depending on the type of alkali.

On the other hand, when grout is injected, conventionally,
Only fresh water, usually tap water, is used. Even when fresh water is added to the granulated blast furnace slag, it is chemically hydrolyzed and hardened in the same manner as Portland cement, in addition to the physical action due to the fine particles.
However, in this case, as described later, the breathing rate is large and the permeability to the ground is not good.

[0008] Accordingly, an object of the present invention is to reduce the breathing rate and improve the permeability in the case of using a calcium-containing substance such as granulated blast furnace slag as a grout injector by directly utilizing the excellent hydraulic property. It is in.

[0009]

In order to achieve the object of the present onset which the above-mentioned problems are eliminated
Ming grout filler has a calcium oxide content of 20
A 50% by weight, suspension der more than 90% of the internal structure is glassy, and Blaine value relative to the fine powder of more than 5000 cm ² / g, was added seawater or seawater contamination groundwater
It is characterized in that that.

[0010]

According to the present invention, when groundwater is added to seawater or near the coast to calcium oxide-containing substances such as granulated blast furnace slag, the potential of each ion contained in the seawater or groundwater near the coast increases the blast furnace granulated slag. The fine particles come to repel, and the breathing rate decreases in order to suppress the sedimentation of the particles. Further, the hydrolysis of the granulated blast furnace slag particles is promoted, and a solidified body having high strength can be obtained.

[0011]

Now, the present invention will be described in further detail with reference to Examples. In the present invention, a fine powder having a calcium oxide content of 20 to 50% by weight, 90% or more of the internal structure being vitreous, and having a Blaine value of 5000 cm ² / g or more is used.

As a typical example, fine powder of granulated blast furnace slag can be mentioned. Other metallurgical slags can also be used. The content of calcium oxide is more preferably 25 to 35% by weight. The Blaine value is more preferably 8000 to 16000 cm ² / g in terms of permeability. In the case of coarse particles, permeability to the ground is poor. Even with a higher Blaine value, there is not much improvement in permeability,
In addition, the cost required for pulverization is increased.

[0013] Seawater or groundwater near the coast is added to this type of granulated blast furnace slag. Was suspended granulated blast furnace slag fine Shimizu, this may be added the groundwater seawater or coast near, but may also be suspended the granulated blast furnace slag fine groundwater directly seawater or shore near. Granulated blast furnace slag is 100-700kg / m in suspension
Preferably ³ are dispersed.

In any case, it is preferable that each ion is present in one liter of the suspension as described below. <Curing reaction accelerating liquid neutral ^{region> Na +: 10000~100000 mg, Cl} -: 10000 ~ 50000 mg K +: 200~ 10000 mg, SO 4 -: 3000 ~ 10000 mg Ca 2+: 200~ 20000 mg, ^{_{SiO 3 -: 5000 ~100000 mg Mg}} 2+: 200~ 50000 mg, HCO 3 -: 2000 ~ 20000 mg Al 3+: < curing reaction accelerating liquid of weak alkali ^{region> 200~ 50000 mg Na +: 100000~1000000} mg ^{, Cl -: 10000~ 50000 mg K} +: 200~ 10000 mg, SO 4 -: 5000~ 50000 mg Ca 2+: 20000~ 100000 mg, SiO 3 -: 100000~500000 mg mg 2+: 50000~ 150000 mg, _{^{HCO 3 -: 20000~200000 mg Al 3+}} : grouting agent according to 200 to 50000 mg present invention is usually injected into the target ground in advance formulated one-pack the materials.

[Examples] Examples will be shown below to clarify the effects of the present invention. Fine powder of granulated blast furnace slag (the Blaine value 15000 cm ² / g), tap water (Shimizu), seawater neutral region, was added to seawater weakly alkaline region, suspension granulated blast furnace slag is 200 kg / m ³ When injecting the liquid into Toyoura Morudo filled with standard sand, breathing rate, setting time, (time required to be 50cm penetration) permeability were examined 3 days strength of Sandogeru, the intensity change to wood age, 1 to The result shown in FIG. 5 was obtained. It has been found that the addition of seawater or groundwater near the coast according to the present invention improves permeability, increases strength, and is similar in strength to Portland cement.

[0016]

As described above, according to the present invention, when a grout injecting agent is used by directly utilizing the excellent hydraulic property of a calcium-containing material such as granulated blast furnace slag, the bleeding rate is reduced and the permeability is reduced. Can be improved.

[Brief description of the drawings]

FIG. 1 is a bar graph showing the breathing rate according to the difference in suspension.

FIG. 2 is a bar graph showing the setting time for different suspensions.

FIG. 3 is a bar graph showing the permeability of different suspensions.

FIG. 4 is a bar graph showing the 3-day strength of a sandgel with different suspensions.

FIG. 5 is a graph showing the change in strength with age due to the difference in suspension.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C09K 17/02 C04B 28/08 E02D 3/12 101

Claims (1)

(57) [Claims] 1. The method according to claim 1, wherein the content of calcium oxide is 20 to 50% by weight, and 90% or more of the internal structure is glassy .
A grout filler comprising a suspension obtained by adding seawater or groundwater mixed with seawater to a fine powder having a brane value of 5000 cm ² / g or more.