JP2882259B2 - Hydraulic material and self-hardening stabilizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic material such as mortar and concrete, and a self-hardening stabilizer , and more particularly to a self-hardening stabilizer used in an underground continuous wall method.

[0002]

2. Description of the Related Art In the underground continuous wall method, the ground is excavated in a trench shape while preventing collapse of a side wall with a stabilizing liquid, and after excavation is completed, an underground wall is constructed in the trench. The construction method and the like vary depending on the purpose of providing the underground wall, the depth of the trench, and the like.

[0003] For example, when an underground wall is used as an earthquake-resistant wall of a main structure, the stable liquid is replaced by concrete by pouring concrete with a tremy tube or the like, and a high-strength underground wall is placed in a trench. Build a wall.

On the other hand, when the underground wall is used as a water stop wall, a water barrier, or the like, a so-called self-hardening stabilizer which is less expensive than concrete is used because the strength required for the underground wall is relatively small. Often. The self-hardening stabilizer prevents the collapse of the side wall during excavation, and hardens itself after excavation to form the underground wall.

Here, when the underground wall is deep, the excavation amount increases or the excavation ground becomes strong, and the excavation time becomes longer. Therefore, during excavation, a stabilizing solution containing a polymer, bentonite, or the like is used without using the self-hardening stabilizer, and after excavation, the underground wall is built in the trench by replacing the self-hardening stabilizer with the self-hardening stabilizer.

[0006]

However, the difference between the specific gravity of the conventional self-hardening stabilizer and that of the stable solution such as bentonite mud is not so large. There was a problem that the quality of the underground wall was deteriorated as a result.

The present invention has been made in view of the above-mentioned circumstances, and provides a self-hardening stable liquid which has a good substitution property with a stable liquid such as bentonite muddy water and is suitable for water shielding, earth retaining and the like. With the goal.

[0008]

To achieve the above object, according to an aspect of, self-hardening stable solution of the present invention as described in claim 1, self-hardening comprising water, hydraulic cement and a predetermined aggregate
In a stable liquid , a swelling substance such as bentonite is dispersed in a swollen state.

Further, the hydraulic material of the present invention is a hydraulic material containing water, hydraulic cement and a predetermined aggregate, wherein the aggregate is substantially composed of fine aggregate. Then, the water, the hydraulic cement and the aggregate are mixed with 1 part of hydraulic cement at a weight ratio of 3 to 8 parts of aggregate and 0.5 to 1.5 parts of water to form a mortar. At the same time, bentonite is mixed with water at a weight ratio of 0.03 to 0.2 part of bentonite to 1 part of water to form muddy water, and the mortar and the muddy water are mixed with 1 part of the mortar to the muddy water. Are mixed at a volume ratio of 0.2 to 1 part.

According to a third aspect of the present invention, there is provided a hydraulic material including water, hydraulic cement, and a predetermined aggregate, wherein the aggregate is substantially composed of fine aggregate. The water, the hydraulic cement, and the aggregate are mixed with 1 part of hydraulic cement at a weight ratio of 4 to 6 parts of aggregate and 0.7 to 1 part of water to form a mortar. , Bentonite was mixed with 1 part of water at a weight ratio of 0.07 to 0.12 parts of bentonite to form muddy water, and the mortar and the muddy water were mixed with the mortar 1 part.
Part, and the muddy water is mixed at a volume ratio of 0.4 to 1 part. Also, the self-hardening stabilizer of the present invention
Is formed of the hydraulic material according to claim 2 or 3.
It was done.

[0011]

In the hydraulic material and the self-hardening stabilizer of the present invention, since a swelling substance such as bentonite is dispersed inside a mortar or the like in a swollen state, a predetermined amount of water is retained in the swelling substance and breathing is performed. Water is less likely to be generated. In addition, since the swelling substance has such a water retention ability, the amount of water can be increased, and the fluidity at the time of casting is improved. The hydraulic material of the present invention includes various applications.
The use of self-hardening
Includes constant solution.

[0012]

EXAMPLES Examples of the hydraulic material and the self-hardening stabilizer according to the present invention will be described below with reference to the accompanying drawings. What
In this example, a hydraulic material was used as a self-hardening stabilizer.
The following describes an example in which there is a case.

FIG. 1 is a schematic diagram showing the composition of the self-hardening stabilizer of this embodiment. As can be seen in the figure, the self of the embodiment
In the hard stabilizing liquid , bentonite 5 as a swelling substance is dispersed in a swelling state in a mortar 4 containing water 1, hydraulic cement 2, and sand 3 as fine aggregate.

To disperse bentonite in a mortar in a swollen state, first, water and bentonite are mixed at a predetermined ratio to form muddy water. The ratio of water to bentonite is preferably in a weight ratio of 0.03 to 0.2 part of bentonite to 1 part of water, and more preferably 0.07 to 0.12 part of bentonite. preferable.

In producing muddy water, it is preferable to reuse the muddy water generated by the continuous underground wall construction method or the like. That is, the amount of bentonite contained in the generated muddy water is checked, so that the weight ratio of water to bentonite is in the above range,
Add fresh water or bentonite and mix with a mud mixer.

On the other hand, poorly mixed fluid mortar is prepared by mixing water, hydraulic cement and aggregate at a predetermined ratio.
The ratio of hydraulic cement, aggregate and water in the poorly mixed fluid mortar is 3 to 8 parts of aggregate and 0.5 to 1.5 parts of water per 1 part of hydraulic cement in weight ratio. However, it is more preferable to use 4 to 6 parts of aggregate and 0.7 to 1 part of water with respect to 1 part of hydraulic cement. Also,
The aggregate may consist essentially of fine aggregate, ie of sand.

Next, the clay mortar as a self-hardening stabilizer is prepared by mixing the muddy water and the poorly blended fluid mortar.

The ratio of the muddy water and the poorly mixed fluid mortar in the clay mortar is such that the volume ratio of the poorly mixed fluidized mortar is 1
The amount of muddy water is preferably 0.2 to 1 part per part, and more preferably 0.4 to 1 part per 1 part of poorly mixed fluid mortar.
Parts.

FIG. 2 shows a state in which bentonite 5 is once added to water 1 to form muddy water, and this muddy water is mixed with mortar 4 in accordance with the above-described procedure.

As can be seen from FIG. 1, once the bentonite 5 is added to the water 1, water penetrates between the layers of the bentonite 5 and remarkably swells between the layers. Is shown. Such bentonite muddy water inherits its properties even in the mortar 4 and forms a stable aggregated structure (card house).

When powdered bentonite 5 is directly added to the mortar 4 as shown in FIG. 3, the bentonite 5 is inhibited from swelling due to the action of calcium ions eluted from the cement particles and does not exhibit swelling properties. It remains in the mortar 4 as it is.

When the mortar 4 hardens in such a state, excess water 6 floats on the surface as breathing water, and the quality inside the mortar varies greatly.

That is, it has been found that it is extremely important to previously convert bentonite into muddy water and to add the muddy water to the mortar in order to disperse the bentonite in the mortar in a swollen state.

Next, some laboratory experiments were conducted on the production of the above-mentioned self-hardening stabilizer , and the results of those experiments will be described below.

(Experimental Example 1) First, the experimental results of clay mortar using fine aggregate collected at point A will be described.

Table 1 shows the weight ratio of poorly mixed fluid mortar. The blast furnace cement B was used as the cement.

[0027]

[Table 1] As can be seen from the table, in this experiment, the water-cement ratio W / C was 1.0, and the sand-cement ratio S / C was 4.0.

Next, Table 2 shows the weight ratio of the water constituting the muddy water to the bentonite.

[0029]

[Table 2] As can be seen from the table, the weight ratio of water to bentonite is
1: 0.1.

Table 3 shows that mortar and mud mixed according to Tables 1 and 2 were mixed at different volume ratios to form a clay mortar, and its density, P-fall time, small slump flow, breathing and compressive strength were determined. It is a result of the measurement.

Here, the P funnel falling test is a test for measuring the fluidity of mortar. The volume ratios of mortar and mud are 1: 0.2, 1: 0.35, 1: 0.4.
9, 1: 0.69.

[0032]

[Table 3] FIG. 4 is a graph of the results shown in Table 3,
4 (a) shows the uniaxial compressive strength, FIG. 4 (b) shows the small slump flow and the breathing rate, and FIG. 4 (c) shows the P funnel falling time with the volume ratio of muddy water and mortar plotted on the horizontal axis. .

As can be seen from these figures and tables,
The daily compressive strength is 12 to 62 kgf / cm ² , the small slump flow is 36 to 47 cm, the breathing rate is 2.2 to 2.6%, the P funnel flow time is about 10 to 14 seconds, and the specific gravity is 1.6 to 1. It became 9.

In this experimental example, the specific gravity was increased by about 50% as compared with the conventional self-hardening stabilizer (specific gravity of 1.15 to 1.2, and the breathing rate of about 5 to 10%). Was reduced to about one third.

When powdered bentonite was directly mixed with the mortar, the amount of breathing water was increased as described above, and the breathing rate was about 5 to 20%.

(Experimental Example 2) Next, experimental results of clay mortar using fine aggregate collected at point B will be described.

Table 4 shows the weight ratio of poorly mixed fluid mortar.

[0038]

[Table 4] As can be seen from the table, in this experiment, the water / cement ratio W / C was 0.7 and the sand / cement ratio S / C was 4.0.

Next, Table 5 shows the weight ratio of the water constituting the muddy water to the bentonite.

[0040]

[Table 5] As can be seen from the table, the weight ratio of water to bentonite is
1: 0.1.

Table 6 shows that mortar and mud mixed according to Tables 4 and 5 were mixed at different volume ratios to form a clay mortar, and its density, P funnel flow time, small slump flow, breathing and compressive strength were determined. It is a result of the measurement.

The volume ratio between mortar and muddy water is 1:
0.16, 1: 0.23, 1: 0.35, 1: 0.4
9, 1: 0.67.

[0043]

[Table 6] FIG. 5 is a graph of the results shown in Table 6,
5 (a) shows the uniaxial compressive strength, FIG. 5 (b) shows the small slump flow and the breathing rate, and FIG. 5 (c) shows the P funnel falling time with the volume ratio of muddy water and mortar plotted on the horizontal axis. .

As can be seen from these figures and tables,
The daily compressive strength is 20 to 106 kgf / cm ² , the small slump flow is 30 to 47 cm, the breathing rate is 1.4 to 2.1% or less, the P funnel flow time is about 10 to 20 seconds, and the specific gravity is 1.7. About 2.0.

In this experimental example, the specific gravity was increased by about 66% and the breathing rate was reduced to about one third to one fifth as compared with the conventional self-hardening stabilizer.

(Experimental Example 3) Next, experimental results of clay mortar using fine aggregate collected at the point C will be described.

Table 7 shows the weight ratio of poorly blended fluid mortar.

[0048]

[Table 7] As can be seen from the table, in this experiment, the water cement ratio W / C was 1.0, and the sand cement ratio S / C was 5.0.

Next, Table 8 shows the weight ratio of the water constituting the muddy water to the bentonite.

[0050]

[Table 8] As can be seen from the table, the weight ratio of water to bentonite is
1: 0.09.

Table 9 shows that the mortar and the mud mixed according to Tables 7 and 8 were mixed at different volume ratios to form a clay mortar, and the density, P-fall time, small slump flow, breathing and compressive strength were determined. It is a result of the measurement.

The volume ratio between mortar and muddy water is 1:
0.54, 1: 0.67, 1: 0.82, 1: 1.00
4 cases.

[0053]

[Table 9] FIG. 6 is a graph of the results shown in Table 9,
FIG. 6 (a) shows the uniaxial compressive strength, FIG. 6 (b) shows the small slump flow and the breathing rate, and FIG. 6 (c) shows the P funnel falling time with the volume ratio of muddy water and mortar plotted on the horizontal axis. .

As can be seen from these figures and tables, 28
The daily compressive strength is 5 ~ 15kgf / cm ² , small slump flow is about 50cm, breathing rate is about 3 ~ 4%, P
The funnel falling time was about 9 to 10 seconds, and the specific gravity was about 1.6 to 1.8.

In this experimental example, the specific gravity was increased by about 40% and the breathing rate was reduced to about one third to one half as compared with the conventional self-hardening stabilizer.

(Experimental Example 4) Next, experimental results of clay mortar using fine aggregate collected at point D will be described.

Table 10 shows the weight ratio of poorly blended fluid mortar.

[0058]

[Table 10] As can be seen from the table, in this experiment, the water / cement ratio W / C was 0.7 and the sand / cement ratio S / C was 4.0.

Next, Table 11 shows the weight ratio of the water constituting the muddy water to the bentonite.

[0060]

[Table 11] As can be seen from the table, the weight ratio of water to bentonite is
1: 0.1.

Table 12 shows that the mortar and the mud mixed according to Tables 10 and 11 were mixed at different volume ratios to form a clay mortar, and its density, P-fall time, small slump flow, breathing and compressive strength were determined. It is a result of the measurement.

The volume ratio between mortar and muddy water is 1:
0.16, 1: 0.23, 1: 0.35, 1: 0.4
9, 1: 0.67, 1: 0.78, 1: 0.90.

[0063]

[Table 12] FIG. 7 is a graph of the results shown in Table 12. FIG. 7 (a) is a uniaxial compressive strength, FIG. 7 (b) is a small slump flow and a breathing rate, and FIG. The time is shown with the volume ratio of muddy water and mortar on the horizontal axis.

As can be seen from these figures and tables, 28
The daily compressive strength is 20 to 130 kgf / cm ² , the small slump flow is about 10 to 40 cm, and the breathing rate is 1.5
When the mixing ratio of mortar and muddy water is 1: 0.49, 1: 0.67, 1: 0.
13 to 23 for 4 cases of 78, 1: 0.90
The specific gravity was about 1.6 to 1.8 in seconds. In addition,
Mixing ratio of mortar and muddy water is 1: 0.16, 1: 0.2
3, the falling time of the P funnel could not be measured for the three cases of 0.35.

In this experimental example, the specific gravity was increased by about 40% and the breathing rate was reduced to about one-fifth to one-half as compared with the conventional self-hardening stabilizer.

As described above, the self-hardening property of this embodiment is
In the constant solution, bentonite is dispersed in a mortar in a swollen state, so that it is possible to improve economical efficiency, water-blocking property, fluidity and uniformity of quality while maintaining predetermined strength and durability.

That is, since a water permeability of about 10 ⁻⁸ cm / s can be secured, even when a thin steel plate is jointed in a thin water blocking wall, for example, it is possible to sufficiently prevent water leakage from the seam of the steel plate. be able to.

Also, by increasing the water cement ratio, the flowability of the P funnel falling time can be assured as about 10 seconds, so that the excavated cross section is small and the thin steel plate or H-shaped steel is included in the cross section. Even if it is inserted, it is possible to satisfactorily fill the gaps with clay mortar.

By swelling the bentonite with a predetermined amount of water, the breathing rate can be suppressed to about 3%, and the uniformity of quality can be improved.

Also, since a uniaxial compressive strength of about 10 to 30 kgf / cm ² can be obtained, after a predetermined number of days,
It is possible to obtain a strength that can sufficiently withstand the earth pressure or the water pressure.

Further, since the ratio of aggregate in the mortar is increased, the specific gravity is increased as compared with the conventional self-hardening stabilizer, and the replacement property with the stabilizer containing bentonite, polymer and the like is remarkably improved, and high quality is obtained. Underground walls can be built.

Further, since the amount of cement in the mortar is reduced, the cost of the underground wall can be reduced.

Therefore, it is possible to economically construct a high-quality thin water barrier in a trench having a small excavated cross section, and not only a normal temporary water barrier, but also an underground dam, a waste disposal site, and the like. It is a very effective means for impermeable walls such as dam bottoms or underground walls for liquefaction countermeasures. In addition, self-hardening
Not only used as a constant solution for construction of underground walls, but also hydraulic materials
It can be used for backfill after excavation, especially for backfilling narrow and complex spaces, backfilling or reclaiming segments during tunnel excavation in the shield method, and can be used underwater or on land. Absent.

Further, since the aggregate is substantially made of fine aggregate, even when the trench width is very narrow or when an H-shaped steel, a steel plate, or the like is provided in the trench, it reaches every corner in the trench. The clay mortar of this embodiment can be filled.

Further, since the muddy water to be mixed with the poorly mixed mortar is made from a stabilizing solution for stabilizing the pore walls, it is possible to effectively use the stabilizing solution which had conventionally been subjected to a predetermined treatment and then discarded. it can.

Thus, the total cost of the underground wall can be further reduced, and the amount of waste can be reduced to reduce the influence on the environment.

Although not particularly mentioned in the above Examples, if necessary, a commonly used fluidizing agent, water reducing agent, separation reducing agent, foaming agent, foaming agent, curing accelerator, curing retarder Needless to say, an admixture such as an agent may be appropriately added to muddy water, mortar or clay mortar.

In the present embodiment, the water cement mixture is described as being limited to mortar. However, the present invention is not limited to such a material, and the present invention can be applied to concrete in which the aggregate is composed of fine aggregate and coarse aggregate. Can be applied.

In this embodiment, bentonite is used as the swelling substance. However, other clays such as kaolin clay or other swelling substances such as a polymer which is a water-soluble polymer may be used. Good.

In the present embodiment, the muddy water for adding mortar was prepared by reusing the stabilizing solution for stabilizing the pore walls. However, separately from the stabilizing solution for stabilizing the pore walls, water and bentonite were newly added to the muddy water. It may be mixed with a mixer etc. and mixed with the mortar, or the mud generated by other ground excavation methods using mud such as mud shield method, reverse pile method, earth drill method, etc. You may. Also, washing water of a crushed stone factory may be used.

Construction waste can be reduced by reusing such muddy water. Therefore, it is possible to reduce waste treatment costs (dehydration and water reduction, cement solidification, or landfill disposal costs thereof) and minimize the impact on the environment.

[0082]

As described above, the hydraulic material of the present invention
According to the self-hardening stabilizer, it is possible to improve economical efficiency, water-blocking property, fluidity and uniformity of quality while maintaining predetermined strength and durability.

[0083]

[Brief description of the drawings]

FIG. 1 is a schematic view showing the composition of a self-hardening stabilizer according to the present embodiment.

FIG. 2 is a view for explaining the action of the self-hardening stabilizer according to the present embodiment.

FIG. 3 is a diagram for explaining a case where bentonite is directly added to mortar.

FIG. 4 is a graph showing test results of a self-hardening stabilizer according to a first experimental example.

FIG. 5 is a graph showing test results of a self-hardening stabilizer according to a second experimental example.

FIG. 6 is a graph showing test results of a self-hardening stabilizer according to a third experimental example.

FIG. 7 is a graph showing test results of a self-hardening stabilizer according to a fourth experimental example.

[Explanation of symbols]

 Reference Signs List 1 water 2 cement particles 3 fine aggregate (sand) 4 mortar 5 bentonite 6 breathing water

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C04B 14:10 14:06)

Claims (4)

(57) [Claims] 1. A water, in self-hardening stabilizing solution containing hydraulic cement and a predetermined aggregate, self-hardening stabilizer, characterized in that the swelling substance such as bentonite is dispersed in a swollen state. 2. A hydraulic material containing water, hydraulic cement and a predetermined aggregate, wherein said aggregate is substantially composed of fine aggregate, and said water, said hydraulic cement and said aggregate are: 1 to 1 part of hydraulic cement, 3 to 8 parts of aggregate and 0.5 to 1.5 parts of water are mixed at a weight ratio to form mortar, and bentonite is added to 1 part of water.
A muddy water is formed by mixing with water at a weight ratio of 03 to 0.2 parts, and the mortar and the muddy water are formed by mixing the muddy water at a volume ratio of 0.2 to 1 part with respect to 1 part of the mortar. A hydraulic material characterized in that: 3. A hydraulic material containing water, hydraulic cement and a predetermined aggregate, wherein said aggregate is substantially composed of fine aggregate, and said water, said hydraulic cement and said aggregate are 4-6 parts of aggregate and 0.7-1 parts of water per part of hydraulic cement
Parts by weight to form mortar, and bentonite is mixed with 1 part of water at a weight ratio of 0.07 to 0.12 parts of bentonite to form muddy water, and the mortar and the muddy water are mixed. A hydraulic material characterized by being formed by mixing the muddy water in a volume ratio of 0.4 to 1 part with respect to 1 part of the mortar. 4. The hydraulic property according to claim 2 or 3.
Self-hardening stabilizer made of material.