Process for the accelerated hardening and improving the strength of various cements

The invention relates to a method for accelerating the curing and increasing the strength of cements, cementitious masses, cement sand mortars and concretes by preparing a mixture of cement, water and a nitrite-containing additive mixture at a temperature of up to 60 ° C, after which the mixture is left to cure at 100 ° C. The invention is useful in the field of seamless and prefabricated structures and in the manufacture of building materials, elements and

products.

There are many well-known methods for accelerating the hardening of cements, which involve using accelerating mixtures either with or without preheating the mixture to 50-60 ° C, or by evaporating or not evaporating the concrete at 80-100 ° C.

The following cement curing accelerating mixtures are known: calcium chloride, sodium chloride, sodium sulphate, potassium sulphate, calcium nitrate, sodium chloride + sodium nitrite, calcium chloride + sodium nitrite, calcium nitrate + calcium nitrite and calcium nitrite + calcium nitrite +

The same mixtures are used for slag-Portland cement as well as Ferro chloride, aluminum chloride, sodium nitrite or magnesium sulphate + sodium nitrate.

The above-mentioned accelerating additives as well as potassium and sodium carbonates are used for Portland pozzolanic cement.

To accelerate the hydration of bellite cement, the addition of cesium chloride + gypsum is highly recommended.

A disadvantage of the known methods for accelerating the hardening of the cement is the insufficient increase in strength at an early stage, i.e. 1.1-1.6 times only.

Another disadvantage is that according to some of these methods, the strength of the cement at a later stage is lower than that of the cements loaded and / or mixed without the additive.

In addition, the most effective additives known today are associated with a high chlorine content, 64% by weight of calcium chloride, 80% by weight of aluminum chloride, etc. This, of course, considerably limits their range of use.

A further disadvantage is that most of the mixtures used are hygroscopic, which makes their initial dry mixing with cement impossible, because before use, especially after long storage, the cement wets and its quality deteriorates.

It is an object of the present invention to obviate all these disadvantages by providing a method for accelerating the curing and increasing the strength of cements, thereby accelerating the curing process, increasing the strength at an early and later stage, and the method itself can spread over a wide range of applications.

The present process is characterized in that an additive mixture comprising 0.5 to 5 parts by weight of dialuminium pentahydroxychloride, 1 to 12 parts by weight of gypsum, 0.5 to 20 parts by weight of lime and 0.01 to 3 parts by weight of nitrite is mixed with 100 weight of cement and water.

The gypsum used herein may contain 0.5 or 2 water of crystallization and the lime may or may not be slaked.

The production of cement masses, cement-sand mortars and concretes can be carried out at ambient temperature or after preheating at 30-90 ° C, preferably at 30-5 ° C. After casting, curing is achieved at ambient temperature or at 30-100 ° C, but preferably at 50-90 ° C.

The described method can be used either for fast-curing cements, or for slow-curing cements such as slag, pozzolanic and bellite cements, in which case it should be noted that fast-curing cements have a lower lime content, i.e. 0.5-5 parts by weight, while slow-curing cements require a larger amount of lime, i.e. 2-20 parts by weight.

The advantage of the invention is the accelerated hardening of the cements, because their strength at an early stage increases 1.6-5.5 ~ times at normal temperature (20 ° C and below) and 1.5-3.5^-by heating the henton mixture or by heat treatment at 50 ° C alone.

In addition, at a later stage, the strength not only remains constant, but tends to increase compared to cements for which this method has not been used.

Another important advantage is that a very small amount of chlorine is used, i.e. only 2-4% of the total weight of the mixture, and in addition the mixture medium is strongly alkaline. Compared to the most effective acceleration mixture, there is 16-32 times less chlorine than calcium chloride and 20-40 times less than aluminum chloride, all of which are acidic media. By including nitrite in the mixture, which neutralizes the effect of this small amount of chlorine as an inhibitor, the field of application of the method expands for different grades of steel-reinforced benton. On the other hand, nitrite plays an important role in the extra strength increase of cements.

Finally, it is a substantial advantage that the mixture is not hygroscopic and can be preliminarily mixed with the cement, i.e. in its initial grinding. The cement thus prepared (including the mixture) is not affected by moisture, so that its inherent quality does not deteriorate before use.

The following examples are provided to illustrate the invention:

Example 1

100 2 parts by weight of dialuminous pentahydroxychloride are added to one part by weight of quick-setting cement or slag or bellite cement, these are dissolved in mixing water and 4 parts by weight (4 parts by weight of slaked lime and 2 parts by weight of slaked lime for half-cement slaked lime in a row. About 0.22 parts by weight of sodium nitrite are also added to half of the charge together with dialumin pentahydrochloride.

The mixtures thus obtained are mechanically mixed with suitable cement-sand mortars with a cement / sand ratio of 1: 3 and a water / cement ratio of 0.5. The vibrating table is used to form faces measuring 4 x 4 x 16 cm. After being removed from the mold, they are cured under water at 20 ° C until tested. For comparison, the same method is used to make cement-sand mortar faces, but in this case mortars without an additive mixture are used. The experimental results obtained are shown in Table 1. It can be seen that the addition of sodium nitrite also accelerates the curing process - in the case of bellite cements, for example. Example 2

100 2 parts by weight of slag or bellite cement are added to 2 parts by weight of dialuminous pentahydroxychloride, these are dissolved in mixing water and 4 parts by weight of semi-hydrated gypsum are added to this solution, followed by 2 or 4 parts by weight of slaked lime. The mixture thus obtained produces a cement-sand mortar with a cement / sand weight ratio of 1: 3 and a water / cement weight ratio of 0.5. One of the bellite-cement compounds contains 6 parts by weight of lime. With such an addition, the mixture can be added dry, i.e. without the use of mixing water, mainly because

1) that the formability of the mortar tends to decrease, thus deteriorating the molding process. For comparison, cement sand mortar faces are made from slag and bellite cements in the same way, whereby the mass is mixed with water without a mixture.

The sample squares, measuring 4 x 4 x 16 cm, are formed from cement-sand mortar using a vibrating table. After they are removed from the mold, they are cured in water until their testing time comes. The experimental results are shown in Table 2. These values ​​show that for slow-curing cements with lower lime impregnation, the addition of the lime component of the mixture results in a significant increase in the curing acceleration according to the method.

Example 3

This relates to the preparation of concrete having the following composition: fast-curing cement / aggregate ratio = 1: 6.5, with a fast-curing cement of 300 kg / m 3 and a water / cement ratio of 0.56. One part of the concrete is mixed with pure water, and the other with water in which the mixture is present, the composition of the latter being 2 parts by weight of dialuminium pentahydroxychloride, 0.22 parts by weight of sodium nitrite (initially dissolved), 4 parts by weight of hemihydrate gypsum and 2 parts by weight slaked lime. Part of the concrete batch is not preheated, in which case the temperature of the concrete batch with or without the mixture is 20 ° C. The materials of the remaining part of the concrete deposit (with or without the mixture) are heated to 50 ° C. The strength of the concrete was tested with cubes measuring 15 x 15 x 15 cm.

In addition, a second concrete batch is prepared with the following ratios: slag-cement / aggregate ratio = 1: 4.5 with a water / cement ratio of 0.42. One part of the concrete is mixed with pure water, but the other is mixed with water and a mixture comprising 2 parts by weight of dialuminium pentahydroxychloride, 0.22 parts by weight of sodium nitrite (initially dissolved), 4 parts by weight of semi-hydrate gypsum and 3 parts by weight of slaked lime. . Concrete, with or without a mixture, is prepared by preheating the material so that the temperature of the concrete insert is 44 ° C and 41.5 ° C, respectively. The strength of the concrete is tested with cubes measuring 15 x 15 x 15 cm.

The strengths shown in Table 3 show that as fast as the fourth hour with high-speed concrete and the sixth hour with slag cement - concrete - this method is used - can be removed from the mold, multiplying the casting cycle, which in turn leads to significant production speeds in construction processes.

Example 4

Cement-sand mortar 1: 3 with a water / cement ratio of 0.5, either without or using a mixture comprising 2 parts by weight of dialuminium pentahydroxychloride (initially dissolved), 4 parts by weight of semi-hydrated gypsum and 2 parts by weight of slaked lime, fed with mixing water for 100 parts by weight of fast-curing concrete, then, together with the molds, is heat-treated at 50 ° C or drawn in air at 20 ° C. The heat treatment time is 6 hours and the strength values ​​obtained are shown in Table 4. The latter clearly show that the heat treatment according to the method greatly accelerates the hardening of cement masses, cement-sand mortars and concretes after their casting.

Example 5

Concrete with a quick-setting s / filler ratio of 1: 6.5 and a fast-setting cement content of 300 kg / 1 m 2 with a water / cement ratio of 0.56 is prepared either without use or with a mixture which in turn contains 2 parts by weight. parts by weight of dialumin pentahydroxychloride, 0.22 parts by weight of sodium nitrite (initially dissolved), 4 parts by weight of semi-hydrate gypsum and 2 parts by weight of slaked lime, the mixture being fed with the mixing water. After pouring the concrete, this is left outside (outside air) to cure at 3-5 ° C until the test time expires. The strengths obtained are given in Table 5 and clearly show that when using the method according to the invention, the increase in strength in the first days is 1.6-1.9times, even under such difficult conditions, the hardening of cement masses, cement sand mortars and concretes accelerates greatly after their casting. Example 6

Three grades of no peakov cement, one slag-sanitary grade, one Portland pozzolanic cement grade and one Portland or bellite cement grade are used to make 1: 3 cement mortars with a water / cement ratio of 0.5, either unused or using a mixture added to the mixing water. which in turn comprises 2 parts by weight of dialuminium pentahydroxychloride (initially dissolved), 4 parts by weight of semi-hydrated gypsum and 2 parts by weight of slaked lime, all these per 100 parts by weight of cement. After being taken from the molds, the samples, measuring 4 x 4 x 16 cm, are cured under water at 20 ° C until the test time has elapsed. The strength of the slag cement is shown for a 1.33-fold increase in the amount of mix. The strengths are given in Table 6.

Table 7 shows the strength of the concrete (using cubes of 15 x 15 x 15 cm), where the concrete has the following composition and ratios: quick-setting cement / aggregates ratio = 1: 6.5, fast-setting cement 300 kg / 1 m and water / the cement ratio is 0.56 and the concrete is hardened at 20 ° C, with or without the use of a mixture added with mixing water. In the first case, the additive comprises 2 parts by weight of dialuminium pentahydroxychloride, 0.22 parts by weight of sodium nitrite (initially dissolved), 4 parts by weight of semi-hydrate gypsum and 2 parts by weight of slaked lime per 100 parts by weight of quick-setting cement. In another case, the composition is 2.66 parts by weight of dialuminium pentahydroxychloride, 0.29 parts by weight of sodium nitrite (initially dissolved), 5 to 32 parts by weight of semi-hydrated gypsum and 2.66 parts by weight of slaked lime per 100 parts by weight of quick-setting cement.

The strength obtained offers a wide range of possibilities - when using the addition of a mixture with mixing water - to accelerate the curing and increase the strength of either cement / sand mortars or concretes in their early stage by 1.7 ~ 3.5 ~ and in their later stage by 1.2-1.3 times .

Example 7

High-speed cement, slag and bellite cement are used to prepare cement-sand mortars with a water / cement ratio of 0.5, without or using a mixture of 2 parts by weight of dialuminous pentahydroxychloride, 1 part by weight of hemihydrate gypsum and 2 parts by weight of parts of slaked lime per 100 parts by weight of cement. The cement is mixed into the mixture dry, i.e. before mixing with water. After removal from the molds, samples of cement / sand mortar, 4 x 4 x 16 cm, are cured under water at 20 ° C until the test time expires.

For comparison, samples of the same size are prepared from slag and bellite cements - »in fact in the same way, but without the mixture, while fast-curing concrete uses a mixture that is added in front of s eko itu sv. The corresponding strengths are shown in Table 8. They show that the method in which the mixture is added dry significantly accelerates the curing of the cement and gives additional strength as well as when the mixture is added with the mixing water.

table 1

Cement / sand mortar 1: 3 compression strength with water / cement ratio 0.5, without adding or adding sodium nitrite to the mixture

<td rowspan="2">Compound</td><td colspan="2">1 day</td><td colspan="2">3 days</td><td colspan="2">28 days</td>

<td>kg / cm</td><td> %</td><td>kg / cm ^ '</td><td> %</td><td>kg / cm^Z</td><td> %</td>

<td>RHC *, with a mixture without nitrite</td><td> 159,1</td><td> 100,0</td><td> -</td><td> -</td><td> 543,1</td><td> 100,0</td>

<td></td><td> 293,2</td><td> 184,3</td><td> -</td><td> -</td><td> 635,9</td><td> 117,1</td>

<td>FHC</td><td> 168,3</td><td> 100,0</td><td> 370,5</td><td> 100,0</td><td> 527,2</td><td> 100,0</td>

<td>RHC, in a mixture with nitrite</td><td> 307,5</td><td> 162,7</td><td> 468,7</td><td> 131,9</td><td> 634,0</td><td> 120,3</td>

<td>SC</td><td> 37,0</td><td> 100,0</td><td> 110,2</td><td> 100,0</td><td> 359,6</td><td> 100,0</td>

<td>SC with a mixture without nitrite</td><td> 60,7</td><td> 164,1</td><td> 161,7</td><td> 164,9</td><td> 447,6</td><td> 124,5</td>

<td>SC in a mixture with nitrite +</td><td> 61,2 .</td><td> 165,4</td><td> 172,7</td><td> 156,7</td><td> 402,8</td><td> 112,0</td>

<td>BC</td><td> 24,3</td><td> 100,0</td><td> 117,1</td><td> 100,0</td><td> 411,5</td><td> 100,0</td>

<td>BC with a mixture without nitrite</td><td> 96,9</td><td> 398,8</td><td> 260,1</td><td> 239,2</td><td> 543,1</td><td> 132,0</td>

<td>BC in a mixture with nitrite +</td><td> 132,6</td><td> 545,7</td><td> 294,9</td><td> 251,8</td><td> 500,6</td><td> 123,6</td>

Hucm .: RHC = High speed hardening cement

RHC = Quick-setting cement that has been stored for a long time before use

SC = Slag cement

Table 2

Cement / sand-mortar 1: 3, compressive strength with water / cement ratio 0.5, and increased lime component in the mixture

<td>Compound</td><td colspan="2">1 day</td><td colspan="2">3 days</td><td colspan="2">28 days</td>

<td></td><td>2 kg / cm</td><td> %</td><td>kg / cm² .</td><td> %</td><td>kg / cm²</td><td> %</td>

<td>SC SC with mixture</td><td> 37,0</td><td> 100,0</td><td> 110,2</td><td> 100,0</td><td> 359,6</td><td> 100,0</td>

<td>SC mixture and double</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>tetun</td><td> 60,7</td><td> 164,1</td><td> 161,7</td><td> 164,9</td><td> 447,6</td><td> 124,5</td>

<td>with the lime component</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td></td><td> 67,2</td><td> 181,6</td><td> 181,1</td><td> 164,3'</td><td> 406,2</td><td> 113,0</td>

<td>BC</td><td> 24,3</td><td> 100,0</td><td> 117,1</td><td> 100, 0</td><td> 411,5</td><td> 100,0</td>

<td>BC with the mixture</td><td> 79,0</td><td> 325,1</td><td> 248,3</td><td> 212,0</td><td> 541,9</td><td> 131,7</td>

<td>BC mixture and double</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>with the lime component</td><td> 96,9</td><td> 398,8</td><td> 280,1</td><td> 239,2</td><td> 543,1</td><td> 132,0</td>

<td>BC mixture and triple</td><td> •</td><td></td><td></td><td></td><td></td><td></td>

<td>lime</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>with the component</td><td> 123,9</td><td> 509,9</td><td> 283,8</td><td> 242,4</td><td> 537,7</td><td> 130,7</td>

Notes: SC = Slag * cement

BC - Bellite cement

Lime Component - Unlike other compounds, the mixture here is mixed dry with cement

Table 3

Compressive strength of concrete without pre-curing and without preheating

Compound hours

<img file="FI58482B_D0001.tif" />

Θ hour ^ kg / crn

<img file="FI58482B_D0002.tif" />

day kg / cm% o Without preheating the concrete mix

RHC-300 kg / 1 m, W / C ratio = 0.56;

without mixture

2Θ kg / cm%

<td>At 20 ° C</td><td> -</td><td> 24</td><td> 100,0</td><td> 210</td><td> 100,0</td><td> 450</td><td> 100,0 1</td>

<td>RHC-300 kg / 1 m³, W / C ratio = 0.56; with the mixture at 20 ° C</td><td></td><td> 59</td><td>245, a</td><td> 317</td><td> 151,0</td><td> 511</td><td> 113,6</td>

RHC-300 kg / l. m, preheating the concrete mix

W / G ratio = 0.56, without mixture

<td>At 50 ° C</td><td> 90</td><td> 100,0</td><td> -</td><td> -</td><td> 241</td><td> 100,0</td><td> 374</td><td> 100,0</td>

<td>RHC-300 kg / 1 m³, W / C ratio = 0.56; with the mixture at 50 ° C</td><td> 148</td><td> 164,4</td><td></td><td></td><td> 299</td><td> 124,1</td><td> 436</td><td> 116,6</td>

<td>SC-410 kg / 1 m³, W / C ratio = 0.42; without mixture at 41.5 ° C</td><td> 26</td><td> 100,0</td><td> 57</td><td> 100,0</td><td> 167,</td><td> 100,0</td><td> 348</td><td> 100,0</td>

<td>SC-410 kg / 1 m³, W / C ratio = 0.42; with the mixture at 44 ° C</td><td> 60</td><td> 230,8</td><td> 122</td><td> 214,0</td><td> 294</td><td> 176,0</td><td> 503</td><td> 144,5</td>

NOTE RHC Fast water te in in cement

SC - Slag cement

W / C - Water / Cement

Table 4

Cement / sand mortar 1: 3, compressive strength water / cement ratio (W / C) 0.5; by heating and without preheating after its formation

Compound hours kg./cm^%

Θ hours kg / ατ7 hours 26 hours kg / crr7% kg / cn7

Curing in air at 20 ° C

<td>RHC</td><td colspan="3"> 11,5</td><td> 100</td><td> 122,3</td><td> 100</td><td> 400,2</td><td> 100</td>

<td>RHC mixture</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>with</td><td> -</td><td> -</td><td> 40,3</td><td> 350,4</td><td> 254,2</td><td> 207,6</td><td> 476,2</td><td> 119,5</td>

Curing by heat treatment at 50 ° C

<td>RHC</td><td> 167,1</td><td> 100,0</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 391,3 100,0</td>

<td>mixture</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>with</td><td> 261,1</td><td> 156,3</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 473,7 121,1</td>

Note. RHC = High speed hardening cement

<td></td><td>Table 5</td>

<td>Compressive strength</td><td>3 For concrete with 300 kg RHC / 1 m and water /</td>

the cement ratio is 0.56 at a curing temperature of 3-5 ° C

<td rowspan="2">Compound</td><td colspan="2">1 day</td><td colspan="2">3 days</td><td colspan="2">28 days</td>

<td>kg / cm '²</td><td> %</td><td>kg / άτι?</td><td> %</td><td>kg / cm 2</td><td> %</td>

<td>Concrete without mixture</td><td> 37,6</td><td> 100,0</td><td> 165</td><td> 100,0</td><td> 430</td><td> 100,0</td>

<td>Concrete with mixture</td><td> 60,0</td><td> 159,6</td><td> 306</td><td> 165,5</td><td> 520</td><td> 120,9</td>

NOTE. RHC = High speed hardening concrete

Table 6

Cement / sand-mortar 1: 3, with a water / serrient ratio of 0.5 compressive strength with and without the mixture, the subsequent is mixed with the cement with mixing water.

Compound day 3 days 28 days

<td></td><td>kg / cn /</td><td> %</td><td>2 kg / cm</td><td> %</td><td>kg / cn /</td><td> %</td>

<td>RHC</td><td> 182,4</td><td> 100,0</td><td> 382,8</td><td> 100,0</td><td> 509,6</td><td> 100,0</td>

<td>RHC ♦ link</td><td> 340,7</td><td> 186,8</td><td> 497,7</td><td> 130,0</td><td> 607,5</td><td> 119,2</td>

<td>RHC^X</td><td> 159,1</td><td> 100,0</td><td> -</td><td> -</td><td> 543,1</td><td> 100,0</td>

<td>RHC^X + link</td><td> 293,2</td><td> 184, 3</td><td> -</td><td> -</td><td> 635,9</td><td> 117,1</td>

<td>RHC^XX</td><td> 161,9</td><td> 100,0</td><td> 343,1</td><td> 100,0</td><td> 528,9</td><td> 100,0</td>

<td>RHC^XXmixture</td><td> 322,1</td><td> 199,0</td><td> 536,1</td><td> 156,3</td><td> 684,3</td><td> 129,3</td>

<td>SC</td><td> 30,0</td><td> 100,0</td><td> 99,1</td><td> 100,0</td><td> 390,6</td><td> 100,0</td>

<td>SC ♦ link</td><td> 51,8</td><td> 172,7</td><td> 176,9</td><td> 178,5</td><td> 459.0</td><td> 117,5</td>

<td>SC * 1.33 fold mixture addition</td><td> 58,8</td><td> 196,0</td><td> -</td><td> -</td><td> 473,7</td><td> 121,3</td>

<td>PC</td><td> 22,7</td><td> 100,0</td><td> 106,6</td><td> 100,0</td><td> 326,7</td><td> 100,0</td>

<td>PC + connection</td><td> 79,7</td><td> 351,1</td><td> 180,1</td><td> 168,9</td><td> 393,1</td><td> 120,3</td>

<td>BC</td><td> 24,3</td><td> 100,0</td><td> 117,1</td><td> 100,0</td><td> 411,5</td><td> 100,0</td>

<td>BC + link</td><td> 79,0</td><td> 325,1</td><td> 248,3</td><td> 212,0</td><td> 541,9</td><td> 131,7</td>

HUDM. RHC, RHC,^X RHC^XX = Fast hardened cement,

SC - slag cement

Pf Puz Zolaani cement

BC = Belite cement. 2

Concrete with quick-setting cement 300 kg / 1 m; water / 58482

Table 7

<td></td><td>cement ratio =</td><td>0.58 - compressive strength using</td><td>or</td><td>without use</td>

<td></td><td>mixture.</td><td></td><td></td><td></td>

<td>Compound</td><td>12 hours</td><td>1 day 3 days</td><td>2Θ</td><td>days</td>

<td></td><td>7 9- kg / cm</td><td>kg / cm² % kg / cm² %</td><td>kg</td><td>/ cm² %</td>

<td colspan="4">Concrete</td><td rowspan="3"> 100,0</td><td colspan="2" rowspan="3"> 333</td><td rowspan="3"> 450</td><td rowspan="3"> 100,0</td>

<td colspan="2">free</td><td rowspan="2"> 100,0</td><td rowspan="2"> 210</td>

<td>mixture</td><td> 95</td>

<td>Concrete * mixture</td><td> 190</td><td> 197,9</td><td> 317</td><td> 151,0</td><td> 406</td><td></td><td> 511</td><td> 113,6</td>

<td>Concrete +1.33 times the addition of the mixture</td><td> 221</td><td> 230,2</td><td> 334</td><td> 159,0</td><td> -</td><td> -</td><td> 551</td><td> 122,4</td>

Cement / sand-mortar 1: 3, compressive strength water / cement14

Table 8

<td rowspan="3">Compound</td><td colspan="2" rowspan="2">with a ratio of 0.5, 1 day □</td><td colspan="4">mixture and cement mixed very dry</td>

<td colspan="2">3 days Ώ</td><td colspan="2">28 days 'of</td>

<td>kg / cnT</td><td> %</td><td>kg / cnf</td><td> ' %</td><td colspan="2">kg / errf%</td>

<td>RHC + mixture</td><td> 287,5</td><td> 100,0</td><td> 480,</td><td> 100,0</td><td> 639,9</td><td> 100,0</td>

<td>RHC + mixture</td><td> 307,3</td><td> 106,9</td><td> 497,8</td><td> 101,9</td><td> 640,9</td><td> 100,2</td>

<td>SC</td><td> 37,3</td><td> 100,0</td><td> 118,7</td><td> 100,0</td><td> 370,2</td><td> 100,0</td>

<td>SC + link</td><td> 68,0</td><td> 184,5</td><td> 176,0</td><td> 140,3</td><td> 420,8</td><td> 113,7</td>

<td>BC</td><td> 24,3</td><td> 100,0</td><td> 117,1</td><td> 100,0</td><td> 411,5</td><td> 100,0</td>

<td>BC + link</td><td> 101,9</td><td> 419,3</td><td> 258,5</td><td> 220,8</td><td> 519,7</td><td> 126,3</td>

NOTE.

RHC - Fast hardened cement

SC - Slag cement

BC - Bdlite cement

Mixture- For comparison, the mixture is added with stirring water.