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  Changing standards or standardization

The standards are as we know the rules that determine what parameters must be met by products or products that they can be admitted to trading on the market and carry these or other markings. Some of the standards are only recommended, others - mandatory. Many years ago, each country had its types of standards (in Poland: works - ZN: XXXXX / XX, industry - BN: XXXXX / XX or national -PN: XXXXX / XX). At each level, they determined the rules of conduct, ways of testing whether certain parameters of the product. With time, the first two types of norms have disappeared and replaced them with standard force of all - national (in Poland, for example. PN - Polish Norm)

Since the 90s, especially after the EU accession of new countries in Eastern Europe, their standards began to be adapted to those applicable throughout the EU. This was a simple reason - the client to buy the same product throughout the common market knew that it meets the uniform requirements in all countries, that the signs, which the manufacturer uses in each country mean exactly the same thing. Symbol is the European standard EN, the Polish standards agreed adapted (standardized) with the European standard (eg. In Poland - PN-EN).

For a long period of time such national standards for cement, and his research was not completely agreed with the standard pan. There were some differences in procedures for testing, the tested parameters or abbreviations used to determine certain properties of the product. This situation has changed, but because of the practical part of the shortcuts can occur simultaneously and it is necessary to select according to which standards and which rules the product has been tested (for Polish): Polish (call it conventionally "old" standard) - PN, or European ( "the new ') - EN.

Changes that have been made are different, part of it is cosmetic, some ordering, and a significant one. In sequence:

1. European standard changed the amount of additive components affecting (improving) the properties of the cement, that is, those which serve eg. For regulators bonding time. Their number may not exceed 1%, and organic additives - 0.2%. Earlier this latter limit of 0.5%. The above amounts do not apply pigments

2. Cements CEM V / B-M (multi) sets the maximum content of pozzolanic and granulated blast furnace slag - it can not exceed 49%. Previously, the limit was 50%.

3. The cements of type CEM II / B-M (compound) of the components nieklinkierowych determined to be at least 12%.

4. Determined properties of special cement - including sulphate resistance

To this group belong cements generally available sulphate-resistant as described in the table below.

Symbols: K - clinker, S - granulated blast furnace slag, P - natural pozzolan, V - fly ash silica. Additionally:

  • Cements CEM I are determined additional content C3A (tricalcium aluminate) in the clinker by numbers using the designation SR and so: for CEM I SR0 content of C3A in the clinker is 0% for CEM I SR3 no more than 3% and for CEM SR5 no more than 5%
  • Blast furnace cements CEM III B - SR or CEM III C - SR does not have limits on the content of C3A, but must be cements low early strength (also referred to the letter L)
  • pozzolanic cements CEM CEM IV A and IV B are sulfate resistant cements (SR), if the content of C3A in the clinker shall not exceed 9%, and may contain (which follows directly from the table), only the addition of natural pozzolan or fly ash silica
Cement type Type of cement resistant to sulphates Share in% by weight
Main ingredients Secondary components
CEM I Portland sulphate resistant cement CEM I - SR0 95-100 0 0 0 0-5
CEM III Blast furnace, sulphate resistant cement CEM IIIB - SR 20-34 66-80 0 0 0-5
CEM IIIC - SR 5-19 81-95
CEM IV Pozzolanic sulphate resistant cement CEM IVA - SR 65-79 0 21-35 0-5
CEM IVB - SR 45-64 36-55

As a result of the adjusted national (in our example: Polish, further explanation as to "Polish" example) standard specifying certain parameters of concrete to be used in chemically aggressive environments. These parameters are contained in the following table.

Note: The exposure classes XA2 and XA3 not use cement types HSR (PN) or SR (according to PN-EN).

Exposition class Environment Max. w/c Min. quantity of cement [kg] Min. concrete strength class
XA1 weak chemical aggression 0,55 300 C30/37
XA2 moderate chemical aggression 0,5 320 C30/37
XA3 strong chemical aggression 0,45 360 C35/45

The final table has been set limit intervals to determine a data environment (water, soil) as a chemically aggressive or not, and if their aggressiveness state, what is its degree. It defines the characteristics that meet the aforementioned designations: XA1, XA2 and XA3.


  • It concerns the land and the natural ground water at a temperature of 5-25C and so the free flow of water, it can be assessed as static conditions
  • Class determines the most unfavorable value of the chemical
  • When two or more parameters point to the same class, the environment must be considered to the next, unless additional tests prove that it is unnecessary
  • Land clay with a permeability of less than 10-5 m / s can be shifted to a lower class
  • * Extraction method recommended SO42- hydrochloric acid alternatively can be performed with water, if appropriate experience in the area where concrete is used
  • ** SO42- limit of 3000 mg / kg should be reduced to 2000 mg / kg if a risk of accumulation of sulphate ions in the concrete due to cyclic drying and wetting or capillary
Chemical property Test method XA1 XA2 XA3
Ground water
SO42- mg/l EN 196-2 >=200 i <=600 >600 i <=3000 >3000 i <=6000
pH ISO 4315 >=5,5 i <=6,5 <4,4 i *4,5 <4,5 i *4,0
CO2 mg/l aggresive pr. EN 13577 >=15 i <=40 >40 i <=100 >100 up to saturation
NH4+ mg/l ISO 7150-1 lub ISO 7150-2 >=15 i <=30 >30 i <=60 >60 i <=100
Mg2+ mg/l ISO 7980 >=300 i <=1000 >1000 i <=3000 >3000 up to saturation
SO42- mg/kg* complete EN 196-2 >=200 i <=3000** >3000** i <=12000 >12000 i <=24000
Acidity DIN 4030-2 >200 Baumann Gully unheard of in practice unheard of in practice

PN-EN 197-1 also indicates that cements resistant to sulphates but do not meet this standard (but complying with national standards) can not be marked with the symbol SR, but only that it is in the national standard. In the case of Polish standards (derived even with industry standards) is the definition of HSR.

The above-described change is for the few european coutries (f. ex. for the Polish market) essential. It means that cements that have passed international studies and in accordance with the guidelines in the standard EN 197-1 (Poland corresponding to the PN-EN 197-1) in the producer country will be able to be identified, and this is associated, also legally operate on the national (in this case: Polish) market as cements resistant to sulphates and be sold as SR, while the cements produced by domestic cement and unexamined in accordance with EN 197-1 only in accordance with our old standards will have to be labeled HSR . This duality for some time will still function. All the time its operation is beneficial for the cement quality produced outside the borders of our country, because almost certainly find that at least some manufacturers will be able to provide the documents that specify their products as such. Low alkaline (in some markets these tests are mandatory, so - results), or resistant to sulphates (more broadly, aggressive environment), because they have already done tests in accordance with standard operational in Europe.

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