JP2002321961A - Heavy weight mortar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide heavy weight mortar containing cement of 100 pts.wt. and corrosion-resistant alloy powder of 200 to 800 pts.wt. having mass per unit volume of 7 t/m<3> or more and the particle diameter of 0.3 mm or less. SOLUTION: The heavy weight mortar has good corrosion resistance and fluidity without causing segregation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weight mortar having excellent corrosion resistance without material separation despite the high ratio of fine aggregate to cement.

[0002]

2. Description of the Related Art Among mortars, heavy mortars using heavy aggregates having a large unit mass are used for injection of radiation shielding walls, earthquake-resistant walls, sound insulation walls, basic structures of machinery and the like. In such a weight mortar composition, there is a problem that material separation easily occurs because the unit volume mass of the aggregate is large, and the fluidity of the mortar is poor.
In addition, there is no material whose dry unit mass exceeds 3.3 t / m ³ , and in particular, when iron powder is used, problems such as material separation and fluidity may significantly occur, and rusting and expansion cracks due to the rusting may occur. This occurred and there was a defect as a mortar cured product.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a weight mortar which is excellent in corrosion resistance and durability, has no material separation, and is excellent in fluidity.

[0004]

Under such circumstances, the present inventors have conducted intensive studies. As a result, by using a specific corrosion resistant alloy powder, there is no crack due to rust, etc., excellent corrosion resistance and durability, and The present inventors have found that mortar with good fluidity can be obtained without material separation even when the volumetric mass is large and the ratio of fine aggregate to cement is high, and the present invention has been completed.

[0005] That is, the present invention relates to a method for producing 100 weight of cement.
Parts per unit mass 7 t / m ^Three0.3m above
200 to 800 parts by weight of corrosion-resistant alloy powder of m or less
It provides weight mortar.

In addition, the present invention relates to (A) 12 to 48 parts by weight of granulated blast furnace slag powder and / or pozzolan fine powder, and (B) substances 3 to 24 which form ettringite, based on 100 parts by weight of cement. Parts by weight, (C) 200 to 800 parts by weight of a corrosion-resistant alloy powder having a unit volume mass of 7 t / m ³ or more and a particle size of 0.3 mm or less, and (D) particles having a unit volume mass of 2.7 to 4.8 t / m ³ . Fine aggregate with diameter of more than 0.15 mm and 5 mm or less 100-500
The present invention provides a weight mortar containing parts by weight.

Further, the present invention provides a radiation shielding member including the weight mortar.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The cement used in the present invention is not particularly limited as long as it is used for ordinary mortar.
For example, any one of ordinary, fast, ultra-high, moderate heat, low heat, etc. Portland cement can be used, and ordinary Portland cement, medium heat Portland cement and low heat Portland cement are particularly preferred.

As the fine powder of granulated blast furnace slag or fine powder of pozzolan of the component (A), ultrafine silica powder is preferable. Component (A) is 12 to 48 parts with respect to 100 parts by weight of cement.
It is preferable to mix them by weight, especially 23 to 42 weight parts.

The substance that forms the ettringite of the component (B) includes aCaO.bAl ₂ O ₃ .cX or aCaO.bAl ₂ O
₃ (wherein, a, b and c represents an arbitrary number, X is a halogen atom, an alkali metal oxide, CaSO _4, Fe ₂ O _3, etc.)
And a compound containing a small amount of alkali metal, silicon, titanium, iron or the like. CaO to C,
When Al ₂ O ₃ is A, Fe ₂ O ₃ is F, and Na ₂ O is N, CA ₂ , C ₃ A, C
_{2 A, CA, C 12 A} 7, C 4 AF, C 11 A 7 · CaCl 2, C 3 A 4 · CaSO 4, C 8
There are NA ₃ , C ₁₁ A ₇ · CaF _{2 and the} like, and specific examples thereof include alumina cement, ultra-rapid hardening cement, calcium aluminate, calcium sodium aluminate, Irwin and the like, and Irwin clinker powder is particularly preferable. component
It is preferable that (B) is blended in an amount of 3 to 24 parts by weight, particularly 3 to 12 parts by weight based on 100 parts by weight of cement.

The corrosion-resistant alloy powder of the component (C) has a unit volume mass of 7 t / m ³ or more, preferably 7.8 t / m ³ or more, and a particle size of 0.3 mm or less. Examples of such corrosion-resistant alloy powders include powders of stainless steel, Cu-Ni-based, Cu-Al-based copper alloys, nichrome, monel metal, and the like.Especially, from the viewpoint of corrosion resistance and availability, stainless steel Are preferred. The corrosion-resistant alloy powder is used in an amount of 200 to 800 parts by weight, preferably 200 to 40 parts by weight, based on 100 parts by weight of cement.
0 parts by weight, particularly preferably 300 to 400 parts by weight. When the amount is less than 200 parts by weight, the dry mass per unit volume is 3.3 t.
/ M ³ can not achieve, material separation occurs exceeds 800 parts by weight.

The fine aggregate of component (D) used in the present invention has a unit volume mass of 2.7 to 4.8 t / m ³ and a particle size of more than 0.15 mm and 5 mm or less. Particle size is 5mm
If the ratio exceeds 1, material separation is likely to occur, and the filling of small gaps is reduced. Examples of such fine aggregates include barite, peridotite, and chromite.
More than one species can be used in combination. Fine aggregate is
100 to 500 parts by weight for 100 parts by weight of cement,
In particular, it is preferable to add 300 to 400 parts by weight. 10
If the amount is less than 0 parts by weight, the amount of cement in the mortar becomes relatively large, so that the heat generation increases, and the possibility of occurrence of thermal stress cracking increases. If the amount exceeds 500 parts by weight, material separation occurs.

The weight mortar of the present invention may further contain a water reducing agent. Examples of the water reducing agent include those containing a modified lignin sulfonate as a main component (LS), those containing a polyalkylallyl sulfonate as a main component (NS), and those containing a melamine sulfonate as a main component. Examples thereof include those having a main component (MS) and those having a polycarboxylic acid as a main component (PC). These water reducing agents may be used alone or in combination of two or more.
0.9 to 4.8 parts by weight, especially 0.1 to 100 parts by weight.
It is preferable to mix 9 to 3 parts by weight.

The weight mortar of the present invention may further contain an antifoaming agent and a foaming agent. As an antifoaming agent, for example, S
N deformer (manufactured by San Nopco) and the like, and examples of the foaming agent include aluminum powder and the like. The defoamer is used in an amount of 0.01 to 1.00 with respect to 100 parts by weight of cement.
It is preferable to mix the foaming agent in an amount of 0.01 to 0.10 part by weight, and the foaming agent is added in an amount of 0.1 to 100 parts by weight of cement.
It is preferable to add 001 to 0.02 parts by weight, particularly 0.001 to 0.01 parts by weight. Furthermore, lime-based expanding material, calcium sulfoaluminate-based expanding material (CSA-based expanding material)
And the like. When these expandable substances are blended, it is preferable to blend 4.5 to 30 parts by weight, especially 6 to 24 parts by weight with respect to 100 parts by weight of cement.

The weight mortar of the present invention can further contain a water-soluble polymer and a water-absorbing polymer, thereby further suppressing material separation. Examples of such a water-soluble polymer include a cellulose-based or acrylic resin-based thickener and the like;
Examples of the water absorbing polymer include sodium acrylate resin.

In the present invention, the components (A) and (B) are
It can be used as an admixture containing these. In addition to the components (A) and (B), a water reducing agent, an antifoaming agent, a foaming agent, an expandable substance, and the like can be added to the admixture.

The weight mortar of the present invention can be used by mixing the composition obtained by mixing the above components with water. Water is 30 to 10 with respect to 100 parts by weight of cement.
0 parts by weight, particularly 50 to 80 parts by weight, is preferred from the viewpoint of fluidity. Further, the unit volume mass is 3.5 t / m.
It is also possible to add ^three or more coarse aggregates to use as concrete. In addition, among the above components, firstly, (D) a fine aggregate and water are mixed, and an admixture containing (A) and (B) is added thereto, (C)
Mortar can also be manufactured by adding and further mixing the corrosion-resistant alloy powder and cement. The mixing ratio of each component is preferably the same as described above.

In the present invention, a cured mortar having a dry unit volume mass of 3.3 t / m ³ or more can be obtained by using the corrosion-resistant alloy powder. Such a cured body can be used in a site having a high shielding performance level in reinforced concrete work in JASS5N nuclear power plant facilities. Further, by further mixing an expansive substance, it is also suitable as a filling mortar for nuclear facilities.

The weight mortar of the present invention is suitable as a radiation shielding member. Radiation shielding members include a reactor shield wall (RSW) in a reactor containment building, a member that can be used to reverse the radiation shielding wall, a temporary opening shielding member used in the heavy block stacking method, and a pipe through hole with shielding restrictions. It can be used for a member to be filled in a space, a member to be filled in a place requiring radiation shielding such as an X-ray room, and the like. It is particularly suitable as a member requiring a dry unit mass of 3.3 t / m ³ or more.

[0020]

The weight mortar of the present invention has no rust,
It has excellent corrosion resistance and durability. Also, even if the ratio of fine aggregate to cement is high, material separation does not occur,
Good fluidity. Further, even when filling a mass mortar with a small wall thickness due to heat generation and a thick wall, temperature stress cracking is suppressed.

[0021]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Example 1 A mortar having the composition shown in Table 1 was produced. The components shown in the table were as shown below. In the obtained mortar,
The amount of water shown in Table 1 was mixed with 100 parts by weight of cement in the composition, and non-separation characteristics (bleeding) were evaluated by the following method. The results are shown in Table 1.

(Cement) Ordinary Portland cement (mass per unit volume 3.16 t /
m ³ ; manufactured by Taiheiyo Cement Corporation) (Metal fine powder 1) Stainless steel fine powder (unit volume mass 7.8 t / m ³ ; particle size 0.30 mm or less) (metal fine powder 2) Iron powder (unit volume mass 7. 9 t / m ³ ; particle size 0.30 mm or less) (fine aggregate 1) barite (unit volume mass 4.2 t / m ³ ; coarse particle rate FM = 2.
50; particle size exceeding 0.15 mm and 5 mm or less) (fine aggregate 2) Chromite-based aggregate (unit volume mass 4.7 t / m ³ ; coarse particle ratio FM = 2.37; particle size exceeding 0.15 mm and 5 mm (Fine aggregate 3) Peridotite aggregate (unit volume mass 3.28 t / m ³ ; coarse fraction FM = 2.84; particle size exceeding 0.15 mm and 5 mm or less)

(Admixture 1) Separation-preventing material; Silica ultrafine powder (silica fume, manufactured by Efaco) 60% by weight, Irwin clinker powder (Clinker No.i described in JP-B-57-8057) 10% by weight 26% by weight; expansive substance; quicklime-based expansive material (mass per unit volume: 3.14 t / m ³ ; Expan, manufactured by Taiheiyo Materials Co., Ltd.); 4% by weight of Kao Corporation; antifoaming agent; SN Deformer 14HP (manufactured by San Nopco) 0.1% by weight (outside); foaming agent; aluminum powder (manufactured by Fukuda Metal Foil Powder) 0.02% by weight (outside) Percent)

(Evaluation method of non-separation characteristics) In accordance with JSCE-F542 filling mortar test method (draft) of JSCE-F542 standard for standard specification of concrete, kneaded mortar is filled, and the upper part is covered with a glass plate. After 3 hours, bleeding water on the surface of the mortar was sampled. A sample without bleeding was evaluated as ○, a sample with bleeding but a small amount that could not be sampled was evaluated as Δ, and a sample with bleeding was evaluated as ×.

[0026]

[Table 1]

From the results shown in Table 1, no material separation occurred in any of the mortars of the present invention.

Test Example 1 The mortar obtained in Example 1 was evaluated for fluidity at 20 ° C., unit mass per unit mass, dry unit mass per unit, and compressive strength. Table 2 shows the results.

(Evaluation Method) (1) Fluidity: The flow time of the J14 funnel was measured in accordance with the JSCE-F542 filling mortar test method (draft) of the Japan Society of Civil Engineers Standard Standard Specifications. The table flow was measured as the fluidity in the horizontal direction using a flow cone according to the JISR5201 cement physical test method. In this case, the spread of the mortar by pulling out the flow cone was measured without performing the table drop 15 times.

(2) Mass per unit volume of kneading: JIS A11
The measurement was carried out according to the unit mass test method for polymer cement mortar that had not yet set and the test method (mass method) based on the mass of air volume. The weight mass uses 400cc,
The kneaded mortar was filled, and the kneaded unit volume mass was calculated from the weight.

(3) Dry mass per unit volume: Standard specifications for construction work and commentary Measured according to the dry unit weight test method of T-601 concrete for reinforced concrete work at JASS5N nuclear power plant facility. The specimen used had a diameter of 10 cm and a height of 20 cm.

(4) Compressive strength: Measured in accordance with the compression test method of JSCE-F542 filling mortar test method (draft) edited by Japan Society of Civil Engineers Standard Specifications for Concrete Specifications. That is,
A specimen of φ5 × 10cm was prepared, cured for 48 hours in a humid empty box at 20 ° C and 90% or more, then demolded and cured in water at 20 ° C until the age of 28 days. Was measured.

[0033]

[Table 2]

From the results shown in Table 2, all of the mortars of the present invention have excellent fluidity in both the J14 funnel falling time and the table flow, the kneading unit volume mass is 3.5 t / m ³ or more, and the drying unit volume mass is 3.3 t / m ³ or more,
Moreover, the compressive strength was high.

Test Example 2 The mortar of Experiment Nos. 4 to 10 obtained in Example 1 was subjected to JIS R 5201 (physical test method for cement).
In accordance with the above, three test pieces of 4 × 4 × 16 cm were formed. After demolding, these specimens were cured at 20 ° C. and 80% for 7 days. Then, after immersing in 3% saline for 24 hours, 72
Time 20 ° C 60% R. H. The cycle of drying was repeated 10 times, and then the state of the surface of the cured mortar was visually observed. Table 3 shows the results. The product of the present invention (N
o.5 to 10), there was no rust generation and no expansion due to the rust, and the surface condition was good.

[0036]

[Table 3]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) (C04B 28/02 C04B 22:06 A 22:06 22:08 Z 22:08 14:36 14:36 14 : 04 Z 14:04 14:30 14:30 22:10 22:10 24:22 A 24:22) 111: 00 111: 00 111: 52 111: 52 (72) Inventor Toru Kagami, Hiroshima City, Hiroshima 1-23 Kyobashi-cho, Ward Hiroshima Ekimae Building Taiheiyo Materials Co., Ltd. F-term (reference) 4G012 PA03 PA11 PA13 PA14 PA29 PB02 PB04 PB05 PB08 PB25

Claims (4)

[Claims] 1. A weight mortar containing 200 to 800 parts by weight of a corrosion resistant alloy powder having a unit volume mass of 7 t / m ³ or more and a particle size of 0.3 mm or less based on 100 parts by weight of cement. 2. A fine powder of granulated blast furnace slag and / or a fine powder of pozzolan 12 to 4 parts per 100 parts by weight of cement.
8 parts by weight, (B) ettringite-forming substance 3 to 24
Parts by weight, (C) Unit volume mass 7 t / m ³ or more, particle size 0.3 mm
200 to 800 parts by weight of the following corrosion-resistant alloy powder, and (D)
With a unit volume mass of 2.7 to 4.8 t / m ³ and a particle size of 0.15 mm
Weight mortar containing 100 to 500 parts by weight of fine aggregate exceeding 5 mm and not more than 5 mm. 3. The cured product has a dry mass per unit weight of 3.3 t /
The weight mortar according to claim 1, wherein the weight mortar is at least m ³ . 4. A radiation shielding member comprising the weight mortar according to claim 1.