JPH03252340A - Hydraulic solidifying composition - Google Patents

Abstract

PURPOSE:To prevent the diffusive separation of a hydraulic composition in water by adding and mixing a water repellent, a swellable clay mineral, a water-soluble polymeric adhesive, etc., to and with the hydraulic composition. CONSTITUTION:A water repellent, a swellable clay mineral and a water-soluble polymeric adhesive are added and mixed to and with a hydraulic composition to provide the hydraulic solidifying composition. The hydraulic composition comprises one kind or more of Portland cement, fast-curing cement slag, lime and gypsum, thereby preventing the diffusive separation of the composition when applied in water and further improving strength, durability, environmental effect, etc., of the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a composition obtained by uniformly dispersing a swellable clay mineral such as bentonite and a dehydrator in a hydraulic composition.

In particular, regarding the construction of embankments underwater, it can be carried out continuously without adversely affecting the surrounding environment, and can be constructed with good kneading and workability using an easy mixing method underwater, and the strength of the resulting construction is reduced. The present invention relates to a hydraulically set composition that has less separation in water, which is a problem in the case of underwater soil concrete.

Therefore, the industrial fields to which the present invention is directly applicable are:
The present invention is applicable to the construction of underwater structures, bottom sediment improvement, construction of underwater embankments, etc. in the marine civil engineering sector, and the present invention greatly contributes to the development of the fishery industry such as port development and coastal fishing.

<Conventional technology> Conventionally, as a material for creating an embankment underwater, aggregate such as crushed stone and a hydraulic composition are mixed together with water, and the mixture is poured onto an underwater pouring surface to form a foundation. It is being created. However, environmental pollution due to water pollution during pouring and a decrease in strength due to material separation were unavoidable.

In particular, in recent years, as part of the effective use of seaside areas, it has been desired to solve the problem of natural destruction and pollution caused by the destruction of seaside ecosystems through dredging and land reclamation of surrounding areas. Currently, research is underway on how to use modern structures in harmony with nature conservation.

In particular, the biggest problem with these methods of use is the generation of pollution during the improvement of the bottom sediment in the water and the creation of embankments, as well as the pollution caused by diffusion. However, this problem could not be solved without elucidation of the solidification composition, such as lack of strength of fill concrete and constructed embankment due to outflow of solidified material.

The present inventors conducted extensive research and arrived at the present invention in order to reduce or eliminate the various problems related to the above-mentioned solidified materials. In other words, a novel solidified composition for constructing underwater embankments that is effective for separation, strength, durability, environment, etc. during underwater construction was obtained.

Means for Solving the Problems> The present inventors added and mixed a TA water agent as a surface modifier to a hydraulic composition, and further added and mixed a swellable clay mineral. , Due to the synergistic effect of the thickening effect of the swellable clay mineral and the TA aqueous property of the water control agent, the particles of the hydraulic composition exhibit remarkable resistance to diffusion separation in water or seawater. We discovered this and arrived at the present invention.

That is, the present invention relates to a hydraulic solidifying composition characterized in that a swelling clay mineral and a water control agent are added and mixed with the hydraulic composition.

In the present invention, the hydraulic composition used includes ordinary cement, ultra-early strength cement, early-strength cement, medium-heat cement, various mixed cements such as portland cement, blast furnace cement, silica cement, and die-nod cement. Hydraulic compositions such as ultra-rapid hardening cement or gypsum, and various types of slag can be mentioned.

Swellable clay minerals used in the present invention include bentonite, hermiculite, kaolinite, mica, and the like. An effective amount of the additive is 5 to 100% by weight based on the hydraulic composition.

On the other hand, as a water control agent for surface-modifying the hydraulic composition to prevent the particles of the hydraulic composition from dispersing into water,
At least one of chlorinated paraffin, liquid paraffin, higher fatty acids such as stearic acid and their salts, metal soaps, polytetrafluoroethylene, especially fibrillated polytetrafluoroethylene, and silicone is used. Although these water control agents may be in the form of fine powder, it is more convenient to form an emulsion using a surfactant or the like and mix it into the hydraulic composition in advance.

Here, to further explain the action of the water repellent, when a swellable clay mineral such as bentonite is added to hydraulic cement a and kneaded, the clay mineral swells and the resulting mortar composition becomes inseparable in water. It was known to improve. However, if a water repellent is further added as in the present invention,
This makes it possible to further increase the inseparability in water.

The reason for this is thought to be that the water repellent adheres to the surface of the water-curable composition, inhibits wetting of the particles with water, and prevents the water-curable composition from dispersing and flowing out into water. This effect is due to the fact that chlorinated paraffin, liquid paraffin, higher fatty acids such as stearic acid, and their salts have a negative effect on water-curable compositions.
It is appropriate to add an amount of 0.5 to 20% by weight, but an even better method is to use polytetrafluoroethylene or silicone as a water repellent. A similar effect can be obtained even if the addition amount is as small as 0.005 to 0.5%.

In addition, when using the hydraulic solidification composition of the present invention, an adhesive such as a water-soluble polymer is mixed in at a weight ratio of about 0.5 to 5%, the viscosity of the mortar composition is adjusted, and breathing phenomenon is caused. In addition to preventing the occurrence of , it is also possible to further improve the inseparability in water.

Furthermore, by adding 5-50% of silica fume, fly ash, etc. to this hydraulic solidified composition, the properties of fill concrete, especially in water, can be improved due to the fluidity microfiller effect and carrier effect. You can also do it.

Hereinafter, the method for producing and using the hydraulic solidifying composition of the present invention will be explained according to Examples.

Example 1 150 g of ordinary Portland cement was placed in a mortar mixer, 10 g of chlorinated paraffin (trade name: Empara 40, manufactured by Ajinomoto Corporation) and 3 g of a surfactant (Lion Corporation, trade name of Mama Lemon) were added as a dispersant, and mixed for 10 minutes. Then, the surface of ordinary cement was treated. Furthermore, after adding and mixing 150 g of bentonite and 700 g of silica sand No. 4, Shimizu 2
40 g was added and kneaded for 2 minutes to prepare a mortar composition.

This mortar composition was subjected to an underwater drop test and measured for compressive strength.

In the underwater drop test, the external size was 11.0 filled with 800cc of water.
Divide 500 g of the kneaded composition into a beaker (volume 11) with a height of 15 cm and a height of 15 cm, and divide it into 10 equal parts.
Immediately after dropping for 0 to 20 seconds, 200 cc of water in the beaker was collected, and the permeability and amount of suspended solids of this water were measured. The transmittance was measured using a spectrophotometer at a wavelength of 660.
The transmittance at a wavelength of mμ was measured using distilled water as a control solution.

The suspended solids were measured according to JIS KO102r factory wastewater test method J14.1.

Compressive strength was measured by placing a cylindrical formwork with a diameter of 5cm and a height of 10cm in a water tank with a depth of 50cm, and then gently dropping the kneaded mortar composition into water from the water surface. The material was poured into the material until it overflowed, and left to stand for 10 minutes, then taken out from the water tank, removed from the mold after one day, cured in water at a water temperature of 20° C., and measured for strength on days 7 and 28. The results were as shown in Table-1.

In addition, as Comparative Example 1, 300g of ordinary Portland cement
and 700 g of silica sand No. 4, and as Comparative Example 2, mortar compositions containing 150 g of ordinary Portland cement, 150 g of bentonite, and 700 g of silica sand No. 4 were prepared. Furthermore, in Comparative Example 3, 20 g of the above chlorinated paraffin was added to 300 g of ordinary Portland cement.
After adding and mixing 6 g of surfactant, add silica sand No. 4 and 7.
A mortar was prepared by adding a predetermined amount of 00g and fresh water. In addition, in Comparative Example 4, 300 g of ordinary Portland cement was mixed with an aqueous emulsion of polytetrafluoroethylene resin (manufactured by Mitsui DuPont Fluorochemical Co., Ltd. Part name: Teflon -20
-J: Solid content concentration 30%) 0.5g was added, heated to 100°C, mixed in a mortar, and fibrillation treatment was performed. A mortar composition was prepared by adding 700 g of silica sand No. 4 and a predetermined amount of fresh water to this. These comparative examples were also subjected to an underwater drop test and a compressive strength test in the same manner as in Example 1.

The results were as shown in Table-1.

Table 1 Example 2 In a mortar, add 1.7 g of an aqueous emulsion of polytetrafluoroethylene resin to 1000 g of ordinary Portland cement.
g (0.05% in terms of solid content) was added and thoroughly mixed in the same manner as in Comparative Example 4 to obtain a water-curable composition whose surface was treated with polytetrafluoroethylene.

150 g of this water-curable composition, 150 g of bentonite, and 700 g of silica sand were placed in a mortar mixer and mixed for 1 minute, and then 240 g of clean water was added and kneaded for 2 minutes to prepare a mortar composition. This mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in Example 1.

Example 3 100 g of ordinary Portland cement and 50 g of gypsum were placed in a mortar mixer, and 10 g of liquid paraffin (manufactured by Chuo Kasei ■) and a surfactant (Mama Lemon) were added as a dispersant.
3 g was added and mixed for 10 minutes to perform surface treatment of the hydraulic composition. Add to this 150g of bentonite and 700g of silica sand No. 4.
g and mixed for 1 minute, then 240 g of clean water was added and kneaded for 2 minutes to obtain a mortar composition.

This mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in Example 1 above.

Example 4 5 g of stearic acid (special grade reagent) and 3 g of a surfactant (Mama Lemon) as a dispersant were added to 150 g of jet cement, and the same treatment as in Example 3 was performed. Add 150g of free expansion type fluorine phlogopite and 700g of silica sand to this,
After mixing for 1 minute with a mortar mixer, 240 g of clean water was added and kneaded for 2 minutes to prepare a mortar composition.

This mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in Example 1 above.

Example 5 150 g of ordinary Portland cement, 50 g of silica hume, and 0.25 g of polytetrafluoroethylene resin aqueous emulsion were placed in a mortar and heated and mixed, then transferred to a mortar mixer, further 10 g of chlorinated paraffin was added, and mixed for 5 minutes to obtain a hydraulic composition. Performed surface treatment on objects. To this, 100 g of bentonite and 700 g of silica sand No. 4 were added and mixed for 1 minute, and then 240 g of fresh water was added and kneaded for 2 minutes to prepare a mortar composition.

This mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in Example 1 above.

Example 6 150 g of blast furnace cement and 1.5 g of silicone (Toshiba SiSilicon TSL8802) were added to a mortar mixer and mixed for 10 minutes to perform surface treatment of the hydraulic composition. To this, 150 g of Hentonai I-1 and 700 g of silica sand No. 4 were added and mixed for 1 minute, and then 240 g of clean water was added and kneaded for 2 minutes to obtain a mortar composition.

This mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in Example 1 above.

Example 7 Ordinary Portland cement 150 in a mortar mixer
After mixing, 3 g of calcium stearate (special grade reagent) and 3 g of a surfactant were added and mixed for 10 minutes to perform surface treatment of the hydraulic composition. To this, 150g of bentonite and silica sand No. 4 67
Add 0g of water and mix for 1 minute, then add 240g of fresh water and mix 2
A mortar composition was obtained by kneading for a minute.

This mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in Example 1 above.

Example 8 A water-soluble polymer adhesive methyl cellulose [Shin-Etsu Chemical @hi-Metrose 90SH-15000] was added at a ratio of 1 to cement during kneading with a mortar having the same composition as in Example 1.
．． A mortar composition containing 0% was prepared, and the compressive strength was measured by an underwater drop test in the same manner as in the above example.

Example 9 In Example 8, polyacrylamide (Orflock AP-1 manufactured by Organo ■) was used as a water-soluble polymer adhesive instead of methylcellulose at a cement ratio of 1.0.
A mortar composition was prepared in which % was added, and the same test as in Example 7 was conducted.

The results from Example 2 to Example 9 are shown in Table-2.

Table 2 A mortar composition similar to that in Example 2 was prepared, and this mortar composition was subjected to an underwater drop test and compressive strength measurement in the same manner as in the previous example.

The results are shown in Table-3. If the amount of polytetrafluoroethylene added is less than 0.005%, the surface treatment effect of the water-curable composition will hardly be observed, and if the amount added exceeds 0.5%, the fibers will not bond together due to fibrillation of polytetrafluoroethylene. The bond became too strong, and when used as a hydraulic solidification composition, it became difficult to mix with hentonite or silica sand, making it difficult to prepare a uniform mortar composition.

Example 10 In Example 2, the amount of polytetrafluoroethylene added was 0.17 g (0,005%) and 0.67 g (0,005%).
0.02%), 1.67g (0.05%), 6.67g
(0.2%), 16.67g (0.5%), five types of hydraulic compositions were prepared in five stages. ．． A rare force.

Furthermore, if the amount added exceeds 20%, the viscosity becomes too large when used as mortar, resulting in a hindrance to the structure.

Table 4 Example 11 In Example 1, the amount of chlorinated paraffin added was 0.7
5g (0.5%), 3.0g (2.0%), 10
g (6.7%), 15g (10%), 30g (20
%) were prepared, and each of them was made into the same mortar composition as in Example 1, and subjected to an underwater drop test and compressive strength measurement.

The results are shown in Table 4. The amount of chlorinated paraffin added is 0.
Evaluation that the surface treatment of the hydraulic composition is effective at 5% or less As shown in Comparative Example 1, when a normal mortar composition is cast as underwater concrete, When the mortar composition is later deposited and spread out, water washes away the parts of the hydraulic composition that are in contact with water, and the strength of the mortar composition in water becomes extremely weak.

In Comparative Example 2, half of the water-curable composition was replaced with bentonite, which is a swelling composition. Due to the effect of bentonite, the inseparability in water was improved, the permeability in water was increased, and the mortar strength when placed in water was slightly higher even though the amount of the water-curable composition was smaller than in Comparative Example 1.

Further, as shown in Comparative Example 3.4, when only a water repellent is added to the water-curable composition, a slight effect of non-separation in water is observed, but it is not sufficient.

In each example according to the present invention, the synergistic effect of the swelling composition and the water repellent agent further increases the non-separation effect when the mortar composition is cast in water, and the water permeability is also higher than in each comparative example. and the strength of the underwater cast mortar composition.
Much higher values were obtained than in each comparative example.

In addition, as shown in Examples 7 and 8, in the mortar compositions to which a water-soluble polymer adhesive is added, the effect of the adhesive imparts viscosity to the mortar, which increases the inseparability in water and improves underwater pourability. Higher strength was also achieved at the time of installation.

Claims (4)

[Claims] (1) Portland cement, quick hardening cement slag,
1. A hydraulic solidifying composition comprising a hydraulic composition comprising at least one of lime and gypsum, a water repellent added and mixed therein, and a swellable clay mineral further added and mixed therein. (2) The hydraulic solidifying composition according to claim (1), further comprising the addition and mixing of a water-soluble polymer adhesive. (3) Claim (2) further comprising adding and mixing at least one of silica fume and fly ash.
The hydraulic solidifying composition described. (4) The hydraulic solidified composition according to claim (3), further comprising the addition and mixing of fine aggregate and coarse aggregate.