JP2008037727A - Water-resistant setting cement material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excellent water-resistant setting cement material which, even in contact with water, is excellent in anti-washout properties, resistance to material segregation, and capability of suppressing ion elution, has fluidity high enough to enable long-distance pumping through a hose and excellent workability, and can develop high strengths after being set. <P>SOLUTION: The water-resistant setting cement material is prepared by mixing 100 pts.wt. cement with 20 pts.wt. fly ash composed of nearly uniformly mixed with 1,000 to 6,000 mesh grains, 5.7 pts.wt. Viscotop (R) which is a micelle agent that electrically associates in the presence of water to form tubular micelle structures, 57 pts.wt. water, and 10 pts.wt. admixture and uniformly kneading the resulting mixture. This material can exhibit water stop performance and high uniaxial compressive strength, has no bleeding tendency, has such excellent long-distance pumpability as to be pumped by 200 m through a 1-inch diameter hose, and is reduced in elution of elutable metal ions of Na, K, Ca, etc., and of hexavalent chromium ions. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gap between a river block, a coastal embankment block, a concrete sheet pile, or a connecting space between underground walls where underground water or water storage is required, and between concrete in an underground structure. Water-resistant cement hardener that can be used to build water-resistant cement hardeners that fill the gaps and joints and form cement-solidified water-cemented cement solids, or floor floors and underwater side walls. Regarding materials.

Conventionally, cement milk and mortar were filled in the gaps and connection spaces between the concrete blocks without water and between the concrete sheet piles, and the blocks were connected to stop water.
However, if cement milk or mortar is filled in the gap or connection space between the dike block, revetment block, concrete sheet pile, etc. that come into contact with water such as rivers and coasts, the cement milk and mortar will dissipate into the water, resulting in a cement hardening material component However, even if the components are separated and hardened, the strength of the cured product is reduced and the quality of the product is not uniform. Further, there has been a problem that the components of the cement hardening material are ion-eluting to deteriorate the environment.
As a countermeasure, a thickener or a micelle agent that causes a micelle structure is mixed in a cement-based hardener. One example is known as publicly known in Japanese Patent Application Laid-Open No. 2002-24935.
However, in order to suppress water separation, a thickener is added to make a non-separated mortar. However, this deteriorates fluidity, cannot pump a long distance hose, and worsens workability. It was.
In addition, a concrete material that is mixed with cement, fine aggregate, and coarse aggregate is mixed with a thickener having a micellar structure to achieve water inseparability, water dissipation, and material non-separation performance. Has been developed.
However, when a thickener having a micelle structure is mixed into a concrete raw material, the fluidity is low and long-distance feeding is difficult.
On the other hand, as an effective method of using fly ash, it is known to be mixed with cement and used as fly ash cement, but when used as a hollow filler, various additives are added to control breathing and fluidity. However, fly ash cement tends to dissipate into the water when used in places where there is groundwater or water boundaries, making it difficult to use in places where it comes into contact with water.
JP 2002-249357 A

  The present invention eliminates these conventional problems and is excellent in workability and hardenability while being excellent in fluidity and long-distance hose pumping while being excellent in water inseparability, material non-separability, and ion elution suppression. An object of the present invention is to provide an excellent water-resistant cement hardener capable of increasing the later strength.

The configuration of the present invention that solves this problem is as follows.
1) A water-resistant cement hardening material comprising cement as a main component, fly ash, and a micelle agent that electrically associates with water in the presence of water to form a tubular micelle structure. 2) A micelle agent is a mixture of a micelle A agent mainly composed of alkylallyl sulfonic acid and a micelle B agent mainly composed of an alkyl ammonium salt. By mixing the micelle A agent and the micelle B agent, The water-resistant cement hardening material according to 1), which expresses a micelle structure 3) 10 to 54 parts by weight of fly ash and 2 to 10 parts by weight of a micelle agent are mixed with 100 parts by weight of cement. The water-resistant cement hardened material according to 1) or 2) 4) The water-resistant cement hardened material according to any one of 1) to 3) added with gypsum 5) Before adding the fine grained cinnabar 1) to 4) in water-resistant cement material according to any one.

  In the present invention, the water, river, shore, lake, pond revetment block, revetment wall that is excellent in water inseparability, fluidity, ion elution suppression, material non-separation, and workability are all in contact with water. -It is useful as a hardened filler that fills and integrates and connects gaps and connecting spaces such as bank blocks and sheet pile blocks.

  The fly ash of the present invention preferably has a particle size of 1000 to 6000 mesh. As the micelle agent, Visco Top (trade name: Kao Corporation) may be excellent.

Hereinafter, the present invention will be described with reference to examples.
In this example, Visco Top (trade name: sold by Kao Corporation) was used as the micelle agent. Biscotop is a micelle A agent of Viscotop A (trade name: Kao Co., Ltd.) based on alkylallyl sulfonic acid and Viscotop B (trade name: Kao Co., Ltd.) based on alkylammonium salt. The micelle B agent was mixed.

In the slurry state kneaded in the present example, the micelle agent of Viscotop is electrically associated, exhibits a tube-like micelle aggregation structure, encloses the components of cement fly ash in the micelle tube, and does not separate in water And suppresses ion elution.
In addition, although the viscosity is increased, thixotropic properties due to the micelle agent and material characteristics are expressed, and the long-distance hose can be pumped without deteriorating the fluidity. The thixotropy also reduces material separation at the pumping / filling stage.

In this example, 20 parts by weight of fly ash in which particles having a particle size of 1000 to 6000 mesh are mixed almost uniformly with respect to 100 parts by weight of cement, 5.7 parts by weight of the above viscotop, 57 parts by weight of water, And 10 parts by weight of an admixture are mixed uniformly.
Using the examples of the above-described component blending, tests were conducted for in-water non-separation performance, pumping performance, ion elution suppression performance, material non-separation performance, volume change performance, strength performance, water stop performance, workability, and flow performance. . Samples A, B, and C having the composition shown in Table 1 were prepared in which the water-resistant cement hardening material of this example was used as sample B, and fly ash cement and conventional mortar were compared with samples A and C, respectively.

Inseparability in water: When the slurry of the water dissipation test example and mortar are injected into the cylinder, the mortar component is discharged from the bottom of the cylinder and melts into the water, so that the lower half of the water in the aquarium It became cloudy. The shape cured at the bottom of the water tank had large irregularities, and the strength was reduced due to non-uniform components and dissolution.
On the other hand, in the slurry of this example, the components dissolved in water and did not become turbid and settled in the water tank, and the components were cured in a plate shape while being uniform, and there was no decrease in strength.

Next, when the slurry-like embodiment and the mortar were flowed down from above the water surface of the aquarium, the flow of the mortar expanded randomly in the water, and the top surface of the mortar arrived at the bottom of the aquarium greatly up and down. Began to undulate. Moreover, the component separation of the mortar component of the hardened | cured material hardened | cured in water was large, and the isolation | separation cement paste phase was recognized below.
On the other hand, in this example, the flow width did not change in water and flowed as a smooth mortar bundle, and the bottom surface of the aquarium became flat without collapsing the upper surface, and there was no separation of components and there was no decrease in strength. . The state is shown in FIGS. 1 (a) and 1 (b). (A) is the flow-down state of the present embodiment, and (b) is the flow-down state of the fly ash cement mortar.

: Ion elution suppression performance 100 g of the water-resistant cement hardener of the example was poured into 1 liter of pure water, and pH and conductivity were measured after a certain time. The dissolution test results for each element are shown in Table 2 (-1) immediately after the start of the test, (-2) after 6 hours, and (-3) after 7 days (-3). The elution of hexavalent chromium was also suppressed to a low value of 0.1 pp or less.

The initial pH of Samples A and B was low, and after 7 days, the pH was nearly the same for Samples A, B, and C near 12.
As can be seen from Table 2, the total concentration of eluted metal ions such as Na, K, and Ca is halved in the sample B of this example compared to the samples A and C. However, Na and K are eluted in large quantities after 7 days (B-3). This is presumably because Na and K are monovalent ions, so the solubility is high and hydration complexes are easily formed. On the other hand, elution of divalent Ca ions is suppressed by adding VT. From this, it is considered that the factor that the conductivity of the sample B increased from that of the sample A after 1 day was due to elution of Na and K ions.
Further, about 0.10 to 0.13 ppm of hexavalent chromium was detected from Samples A and C, whereas Sample B to which VT was added had an environmental standard value of 0.05 ppm or less for hexavalent chromium. Therefore, it can be said that the filler to which Visco Top that can suppress elution of hexavalent chromium is excellent also in this respect.

: Long-distance pumpability The slurry-like water-resistant cement hardener of this example could be pumped by 200 m with a 1-inch diameter hose. In addition, a 2-inch diameter hose can be pumped by 300m, and long-distance pumping performance is high, making it possible to transport to a wide area or far away.
This enabled long-distance pumping by the thixotropy of the micelle agent, and material separation during pumping was greatly reduced.

: Volume change In Sample B of this example, the volume change was small, and almost no breathing was observed. (The breathing rate was close to 1.) On the other hand, the volumetric shrinkage of sample A was 5 times that of sample B. The volume shrinkage rates of Samples A and B are shown in Table 3 below.

: Strength The cured body of this example was cured, and the specimen was taken out of the cured body and subjected to a strength test. As a result, the following average uniaxial compressive strength was obtained, and high uniaxial compressive strength was obtained.
Average uniaxial compressive strength 60.6 N / mm ²

: Breathing and strength / viscosity First, in order to grasp the material separation characteristics, a breathing test was conducted using the polyethylene bag method (JSCE-F533), but the sample B to which VT was added did not cause breathing.
For the strength test, a specimen was prepared using a plastic mold tube of 50 × 100 mm, and was cured in water for 7 and 28 days, and the uniaxial compressive strength was determined. FIG. 2 shows the relationship between the curing days of samples A and B and the uniaxial compressive strength. Table 2 shows the volume shrinkage rates of Samples A and B. FIG. 2 shows that the uniaxial compressive strength of the sample B added with VT is smaller than that of the sample A not added with VT, but there is no significant difference in the 28-day strength. Further, as shown in Table 3, since the volume shrinkage after filling of the sample B is extremely small, uniform filling is possible, and there is an advantage that the slurry does not need to be replenished during breathing.

: Water stoppage (water permeability)
When a water impermeability test was performed using the cured body of the present example, the water permeability coefficient K15 (cm / s) at 15 ° C. was 8.5E-08 as a representative value, and the water permeability (water blocking property). ) Was expensive.

: Workability Workability was uniformly kneaded with a pump, resulting in uniform quality.
When used as a water-stopping filler (connecting material) for concrete sheet piles in the landfill irrigation and drainage project, the water-stopping was good.

According to this example, as shown in Table 4 below, the performance of 1 to 6 was generally superior to that of mortar.

As described above, this example is excellent in quality and workability because it is inseparable in water, fluidity (long-distance hose pumping transportability), material inseparability, and ion elution due to contact with water is suppressed. It became a thing.

  INDUSTRIAL APPLICABILITY The present invention is useful as a cement hardener for ground with rivers, ponds, coasts, and groundwater in contact with water, but can also be used as a general ground filler and a hardened cement for construction.

It is explanatory drawing which shows the flowing-down state to the water tank of the slurry and mortar of an Example. It is explanatory drawing which shows the relationship between the curing days of samples A and B, and uniaxial compressive strength.

Claims (5)

  A water-resistant cement hardening material comprising cement as a main component, fly ash, and a micelle agent that electrically associates in the presence of water to form a tubular micelle structure.   The micelle agent is a mixture of a micelle A agent mainly composed of alkylallyl sulfonic acid and a micelle B agent mainly composed of an alkyl ammonium salt. By mixing the micelle A agent and the micelle B agent, the micelle structure The water-resistant cement hardener according to claim 1, wherein The water resistant cement hardening material according to claim 1 or 2, wherein fly ash is mixed in an amount of 10 to 54 parts by weight and a micelle agent is mixed in a ratio of 2 to 10 parts by weight with respect to 100 parts by weight of cement.   The water-resistant cement hardening material in any one of Claims 1-3 which added and mixed gypsum.   The water-resistant cement hardening material according to any one of claims 1 to 4, wherein fine sand grains are added and mixed.

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