JP2904530B2 - Hydraulic composition - Google Patents

Description

The present invention relates to a hydraulic composition, a cement admixture, and a cement composition mainly used in the field of civil engineering and construction.

[Conventional Technology and Issues] Currently, cement is used for a wide range of applications in the civil engineering and construction fields, and the needs for cement / concrete technology tend to be diversified. Along with this, various performances are required for cement and concrete, for example, rapid hardening required for emergency construction and water stoppage work, and abrasion resistance required for materials such as roads and factory floors. Is one of them.

Conventionally, various admixtures and admixtures have been used as materials covering the performance of cement. However,
For example, except for the AE water reducing agent having both the AE function and the water reducing function, most of them were aimed at improving single function or single performance.

The same is true for hardened materials and wear-resistant materials, and it was not possible to improve the performance of both materials simultaneously with one admixture.

In view of such a current situation, the present inventors have made various studies, and as a result, obtained a finding that a specific composition improves both rapid hardening property and wear resistance of concrete, and have completed the present invention.

[Means for solving the problem]

That is, the present invention provides xCaO.yAl ₂ O ₃ .zCaF ₂ (where x / y
/z=1/0.65 to 1.5 / 0.01 to 0.32) is a hydraulic composition containing calcium fluoroaluminate and a reactive siliceous substance as main components, and the hydraulic composition and inorganic sulfate as main components. And a cement composition containing the cement admixture and cement as main components.

 Hereinafter, the present invention will be described in detail.

In the present invention, xCaO.yAl ₂ O ₃ .zCaF ₂ (where x / y
/ z = 1 / 0.65 to 1.5 / 0.01 to 0.32) is a calcium fluoroaluminate obtained by calcining various raw materials mainly composed of calcareous, alumina and fluoride,
When the molar ratio of O, Al ₂ O ₃ and CaF ₂ is 1, where CaO is 1, Al ₂ O ₃
0.65 to 1.5, CaF ₂ is blended to be 0.01 to 0.32, 1,0
It is obtained by firing at 00 ° C. or higher. In practice,
Further, it is preferable to pulverize and classify to an appropriate particle size, for example, a Blaine value of 1,000 to 8,000 cm ² / g.

The ratio of CaO, Al ₂ O ₃ and CaF ₂ needs to be in the above-mentioned range, and if it is out of the above-mentioned range, one of the objects of the present invention is insufficient wear resistance.

The firing method is not particularly limited, but for example, an electric furnace or a rotary kiln may be used, and the firing time is not particularly limited.

The method for cooling the fired product is not particularly limited, either. For example, any method such as a rapid cooling method using water or high-pressure air or a slow cooling method using standing can be used.

The product can be used irrespective of whether it is crystalline or amorphous, and the presence of other components or impurities is not particularly limited. Especially when considering an industrial process, SiO ₂ , Fe ₂ O ₃ , TiO
₂ , MgO and SO ₃ are expected to be mixed, but the mixing amount of these is usually less than 20% by weight, and the hydraulic composition of the present invention,
It does not impair the physical properties of the cement admixture and the cement composition.

As the reactive siliceous substance used in the present invention, activated silica, opal silica, silica fume, colloidal silica, diatomaceous earth, aerosil, silica gel and glassy sodium 1,2,3,4 sodium silicate, crystalline silica There are sodium silicate-based substances such as sodium metasilicate, sodium orthosilicate, and sodium pyrosilicate, and one or more of these can be used. Among them, the composition of sodium silicate-based material is molar ratio Na ₂ O
/ SiO ₂ = 0.1 to 5.0 is preferred, and those in the range of 0.2 to 1.1 are more preferred, and they can be used in powder or solution form.

The amount of the reactive siliceous substance to be used is 5 to 300 parts by weight, preferably 10 to 200 parts by weight, based on 100 parts by weight of calcium fluoroaluminate. If the amount is other than this, it is difficult to obtain a favorable effect in terms of abrasion resistance.

The particle size of the reactive siliceous substance is not particularly limited, but usually 5 μm or less is preferable.

The inorganic sulfate used in the present invention refers to a sulfate of an alkali metal or an alkaline earth metal, and examples thereof include anhydrous, hemihydrate and dihydrate calcium sulfate, and among them, type II anhydrous gypsum The hardly soluble or insoluble ones such as described above are particularly preferred.

The amount of the inorganic sulfate to be used is 50 to 500 parts by weight, preferably 100 to 300 parts by weight, based on 100 parts by weight of the hydraulic composition. If less than 50 parts by weight, rapid hardening is insufficiently expressed,
If it exceeds 500 parts by weight, the abrasion resistance tends to be insufficient.

The cement used in the present invention may be various kinds of Portland cement such as ordinary / early high strength / very early strength, various kinds of cement mixed with Portrad cement and blast furnace slag, fly ash or silica, or an expanding material added to Portland cement. Expanded cement or even special cement such as alumina cement.

The amount of cement used is preferably 200 to 5,000 parts by weight based on 100 parts by weight of the cement admixture. If it is less than 200 parts by weight, it is not economically preferable. If it exceeds 5,000 parts, rapid hardening performance is insufficient.

In the present invention, further, a setting regulator, silica sand,
Aggregates such as natural sand and gravel, fibers such as glass fiber, carbon fiber and steel fiber, polymer polymer emulsion and rubber latex, coloring agent and pigment, AE agent, water reducing agent, AE water reducing agent,
Superplasticizer, rust inhibitor, non-separable admixture in water such as methylcellulose, thickener, water retention agent, waterproofing agent such as calcium chloride and sodium silicate, foaming agent, foaming agent, antifreezing agent, etc. Alternatively, two or more kinds can be used in combination as long as the object of the present invention is not substantially inhibited.

Specific examples of the setting regulator include citric acid, tartaric acid, gluconic acid, organic acids such as succinic acid and maleic acid or salts thereof, alkali carbonate, phosphoric acids or salts thereof,
Boric acid, alkali borate, silicofluoride, starch, sugar,
Examples thereof include alcohols and mixtures thereof, and one or more of them can be used, and among them, use of an organic acid is preferable.

The amount of the setting regulator used is about 0.1 to 30 parts by weight with respect to 100 parts by weight of the hydraulic composition, so that an appropriate pot life (working time) of tens of minutes to several hours can be obtained. .

For mixing the hydraulic composition, the cement admixture and the cement composition, any existing stirring device can be used. For example, a tilting mixer, an omni mixer (Chiyoda Giken Kogyo), a V-type mixer, a Henschel mixer, and a Nauta mixer can be used. The mixing may be performed by mixing the respective materials at the time of construction, or may be performed by partially or entirely mixing the materials in advance.

Regarding the construction using the cement composition of the present invention,
It is only necessary to follow the conventional mortar or concrete construction, and no special equipment, construction method, etc. are required.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1 A commercially available calcium carbonate as a calcareous raw material, a commercially available alumina as an alumina raw material, and a reagent grade calcium fluoride manufactured by Wako Pure Chemical as a raw material for fluoride were mixed at 1,700 ° C. in a platinum crucible using an electric furnace. After firing under the condition of time, it was dropped into water and rapidly cooled. The resulting product is then
It was pulverized to below μ to produce various calcium fluoroaluminates, which were subjected to the test. The results of analysis of the products are shown in Table 1.

Next, 100 parts by weight of various calcium fluoroaluminate, 100 parts by weight of a reactive siliceous substance, 200 parts by weight of inorganic sulfate, 10 parts by weight of setting agent, 1,200 parts by weight of cement, and 3,000 parts by weight of aggregate were prepared. With W / C = 55%, strength and abrasion resistance were measured.

(Materials used) Reactive siliceous substance a: Silica fume, by-product during ferrosilicon production Inorganic sulfate: Type II anhydrous gypsum, plain value 5,900 cm ² / g Cement: Andes Cement, ordinary Portland cement Setting agent: Reagent, sodium gluconate Aggregate: Toyoura standard sand (Measurement method) Compressive strength: Conforms to JIS R 5201. However, the curing condition is 20
C. x 65% RH.

Abrasion resistance: Using a specimen of 7 days old, wear wheel H-2
2. The wear resistance was examined using a taper abrasion tester with a load of 250 g and 2,000 rotations. The results are shown by the amount of wear (g / 2,000 times).

Example 2 The procedure of Example 1 was repeated, except that the calcium fluoroaluminate of Experiment No. 1-10 of Example 1 was used to change the reactive siliceous material. The results are shown in Table 2.

(Materials used) Reactive siliceous substance b: Reagent, sodium silicate c: Reagent, sodium metasilicate d: Opal quartzite e: Reagent, silica gel Example 3 In the formulation of Experiment No. 1-10 of Example 1, cement The same procedure as in Example 1 was carried out except that the amounts of 2,400 parts by weight, 6,000 parts by weight of aggregate and inorganic sulfate were changed. The results are shown in Table 3.

Example 4 The procedure of Example 1 was repeated, except that the amount of the setting regulator was changed in the formulation of Experiment No. 1-10 of Example 1. The results are shown in Table 4.

Example 5 The procedure of Example 1 was repeated, except that the amount of cement was changed in the composition of Experiment Nos. 1-10 of Example 1. The results are shown in Table 5.

[Effects of the Invention] According to the present invention, a hydraulic composition having high strength and excellent abrasion resistance can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C04B 22/12 C04B 28/00

Claims (3)

(57) [Claims] 1. A _{xCaO · yAl 2 O 3 · zCaF} 2 ( however, x / y / z = 1 /
0.65 to 1.5 / 0.01 to 0.32). A hydraulic composition mainly comprising calcium fluoroaluminate and a reactive siliceous substance. 2. A cement admixture comprising the hydraulic composition according to claim 1 and an inorganic sulfate as main components. 3. A cement composition comprising the cement admixture according to claim 2 and cement as main components.