JPS60108352A - Super quick settable cement composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses calcium aluminate and inorganic sulfate as steep components, and 110 contains c, s, c2s, C4A.
By mixing a specified amount of aluminate, inorganic carbonate, and oxycarboxylic acid and/or its Iy, ii into a rapidly hardening cement containing cement minerals such as , lr, etc., after pouring water, A 1:2 mortar with a hardening time of at least 20 minutes and a 1 hour compression strength of 200
The present invention relates to an ultra-fast hardening cement composition that exhibits an extremely high hydration rate of Kgf/cm2 or more.

Various quick-hardening cement compositions have been proposed in the past, but if the working time required for construction is longer than 20 minutes, the compressive strength after one hour will be about 50 to 100 Kgf/Cm2, which is about 200 Kgf/crn2. It took more than 2 hours to develop the strength. On the other hand, the needs for quick-hardening cement are becoming more and more sophisticated, such as road knowledge in urban areas and railway-related repair work.
In places where it is not possible to block traffic for a long period of time, concrete is required to develop high-strength problems as early as possible. In addition, aluminate is well known as a quick-setting agent for cement, but when used in conjunction with calcium aluminate, what kind of setting regulator and
Even if it were used, it was not possible to secure the working time of about 20 minutes or more required for construction, so it was only used for special purposes where it was not necessary, such as spraying work.

The inventors have discovered that calcium aluminate and force (D)
When aluminate is added to a quick-hardening cement that uses f-acid as a rapid forming agent, the addition of aluminate results in rapid setting, but the pressure of 414+K increases significantly for 1 to 2 hours after water injection, and the long-term strength also decreases. As a result of further intensive research based on the knowledge that an extremely excellent ultra-fast hardening cement can be obtained, we have found that when specific amounts of aluminate, inorganic carbonate, oxycarboxylic acid and/or their salts are used together. , has a curing time of 20 minutes or more required for construction under the mutual effect of each additive, and 1:
They discovered this and completed the present invention.

That is, the present invention provides calcium aluminate versus inorganic 1
In a rapid hardening cement containing 15 to 654% by weight of a rapid hardening component having a weight ratio of 1+f acid salt to 5 to 6 skin,
It is recommended to contain 0.2 to 5% of aluminate, 0.2 to 5% of 4m charcoal salt, and 0.1 to 2% of oxycarboxylic acid and/or its salt, based on the internal cutting weight. ! This is an ultra-fast hardening cement composition with a 1+ sign.

The present invention will be explained in more detail below.

In the present invention, the weight ratio of calcium aluminate to inorganic salt salt is required to be 1:0.5 to 6, preferably 1 to 1.5.If the ratio is other than this, the working time is 20 minutes or more. I can't keep it up or 200 kg in 1 hour
Intensity greater than f/cm2 cannot be obtained.

As calcium aluminate, 12CaO・7A1
203゜3Ca()A1203, Ca0AA203
Amorphous or crystalline forms such as +11Ca0, 7A7203, and CaX2 (X is a halogen) are used, and as the inorganic sulfate, various stones, sodium sulfate, and the like are used. Preferred is 12CaO-7Al2O3
or 12 Ca0.7 JJ203 and Ca04120s
This is a combination of a mixture of Powderness is 3,000cm2/ Blaine value
, lit is sufficient, preferably 4,000~
It is 8.000α2/g. One inch of addition of the steep component is
15-65% by weight based on cement, preferably 25-60%
Weight%. If the addition amount is other than this, the working time will not be taken or high strength will not be obtained.

Aluminate is an important component for achieving the object of the present invention, and it significantly enhances the water-oxygen reaction of the rapid hardening cement made by blending the above-mentioned steep components, resulting in a rate of 200 Kgf/hour.
This is necessary to develop strength of rx2 or higher. In the formulation of the present invention, although it is a rapid setting agent, it exhibits a unique effect of prolonging the curing time, and does not reduce long-term strength. The amount to be added to the rapidly hardening cement is 0.2 to 5%, preferably 0.5 to 2%, based on the weight of internal cutting. When 0.2% uncocooned, the strength of the cocoon was not reached, and when 5%
If the concentration exceeds 1 tlAJ%, the working time cannot be secured even if a 1tlAJ% agent is used, and furthermore, there is a problem in long-term durability.

As the aluminate, sodium aluminate is commonly used.

Next, inorganic carbonates and oxycarboxylic acids and/or their salts function as strength enhancers and setting retardants. Even if they are added alone, the curing time is only slightly extended, and the working time is 20 minutes or more. To ensure this, both must be used together. In addition, saturation is also important, and inorganic carbonate is 0.2 to 5%, preferably 0.5%, based on the internal cutting weight of rapidly hardening cement.
~2%, oxycarboxylic acid and/or its salt 0.1-2
% is preferably 0.2 to 1%. Addition amount other than this,
If this is the case, it will connect instantly and the work time necessary for construction will not be availableG)
Power\ or high strength cannot be obtained. As an inorganic carbonate (well,
Sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, etc. Oxycarboxylic acids or their salts include citric acid, gluconic acid, tartaric acid, malic acid, etc., and their acids sodium, potassium, calcium, etc. water (salt compatible) is used.

As described above, with the ultra-fast hardening cement composition of the present invention, I#:
In a working time of 20 minutes or more, the strength that conventionally required 6 to 6 days can be developed in just 1 hour, and the strength increases steadily thereafter and has excellent long-term durability.
The cured product exhibits effects such as not causing any spotting phenomenon.

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

Example 1 12Ca0・7AA! Calcium aluminate type anhydrite version with plain value 4,800 cFIL2/fi whose main components are 203 and Ca041zO3 (Brain value 6.500 crrt2/,!
9) The rapid hardening component obtained by blending 150 parts of the cement was mixed with commercially available early strength Portolan R cement at a rate of 10 to 40 times by internal cutting, and further added with sodium aluminate and potassium carbonate in an amount of 11j. 1% each, 0.4% citric acid
% was added to prepare the cement composition for use in B.

Curing time (A, STM C40 in a 20'0 constant temperature room)
6-65T) and the 1 hour compressive strength was measured.

The results are shown in Table εα1.

Table 1 (note) below is a comparative example.

Example 2 Example except that the blending amount of the active ingredient was 25% by weight, and the combination of calcium aluminate and type II anhydrite was changed. A test similar to 1 was conducted.

The results are shown in Table 2.

Table 2 Performance 1 ((Example 6) The same test as in Example 1 was conducted except that the dispersion of the ingredient was filled with 25% and the internal cutting strength of the sodium aluminate was changed. The results are shown in Table 6.

Table 6 (Note) 4614, 15.20 is a comparative example, and the others are examples of the present invention.

Example 4 A test was carried out in the same manner as in Example 1, except that the blended amount of the courier component was 25% per bottle, and the addition amount (internal grinding) was changed. The results are shown in Table 4.

Table 4 (note) ~41Wa //621 and 27 are comparative examples, and the others are examples of the present invention.

Example 5 A test was carried out in the same manner as in Example 1, except that the blending amount of the steep component was 25% by weight, and the amount of oxycarboxylic acid or its salt added to the insects (inner side) was varied. The results are shown in Table 5.

Table 5 (Note) Experiments, %31 and 66 are comparative examples, and the others are inventive examples.

Example 6 The ultra-fast-hardening cement composition of Example 1 in which the blending amount of the rapid-hardening component was 25% by weight was externally milled using a commercially available high-temperature cement composition containing β-naphthalene sulfonate formalin condensate salt as the main component. Performance water reducing agent Moe product name [Mighty 100] 1% solid content
The concrete was mixed with a cement amount of 400 m3, a water-cement ratio of 62%, a fine aggregate ratio of 64%, and a slump of 8 on, and the hardening time and compression strength (
φ10cIrL×20cm) was measured. As a comparative example, sodium aluminate was removed from the formulation and tested. The results are shown in Table 6.

Table 6 Patent applicant: nt Keikagaku Kogyo Co., Ltd.

Claims (1)

[Claims] Weight ratio of calcium aluminate to inorganic sulfate is 1:0
．． In a rapid hardening cement containing 15 to 65% by weight of a rapid hardening component consisting of 5 to 6, 0.2 to 5% of aluminate and 0.2 to 5% of inorganic carbonate in heavy melting. % and 1 to 2% of oxycarboxylic acid and/or its jXO.