Durability and service life 19
The durability requirements linked to the listed exposure classes are
expressed in terms of a maximum allowable water/cement ratio and a minimum needed cement content. In an indicative way, also strength classes are
mentioned. All requirements in terms of water/cement ratio, cement content
and strength are locally defined in each European member state. The code
provisions of the ‘place of use’ should be followed when producing concrete
elements in Europe.
While the durability provisions of the European Standard EN 206-1:2000
were summarized in the previous paragraphs as an example, it can be mentioned that a similar approach is followed in many other international standards such as the North American Standard ACI 318:2011, the Canadian
Standard CSA A23.1:2009, the Australian Standard AS 3600:2001, and
the Indian Standard IS 456-2000. Some exposure classes are defined
Table 1.2 Exposure classes defined in European Standard EN 206-1:2000
Exposure classes
no risk of corrosion or attack
X0
corrosion induced by carbonation
XC1
Dry or permanently wet
XC2
Wet, rarely dry
XC3
Moderate humidity
XC4
Cyclic wet and dry
corrosion induced by chlorides other than from sea water
XD1
Moderate humidity
XD2
Wet, rarely dry
XD3
Cyclic wet and dry
corrosion induced by chlorides from sea water
XS1
Exposed to airborne salt but not in direct contact with sea water
XS2
Permanently submerged
XS3
Tidal, splash, and spray zones
freeze/thaw attack with or without de-icing salts
XF1
Moderate water saturation without de-icing agents
XF2
Moderate water saturation with de-icing agents
XF3
High water saturation without de-icing agents
XF4
High water saturation with de-icing agents or sea water
chemical attack
XA1
Slightly aggressive chemical environment
XA2
Moderately aggressive chemical environment
XA3
Highly aggressive chemical environment
The durability requirements linked to the listed exposure classes are
expressed in terms of a maximum allowable water/cement ratio and a minimum needed cement content. In an indicative way, also strength classes are
mentioned. All requirements in terms of water/cement ratio, cement content
and strength are locally defined in each European member state. The code
provisions of the ‘place of use’ should be followed when producing concrete
elements in Europe.
While the durability provisions of the European Standard EN 206-1:2000
were summarized in the previous paragraphs as an example, it can be mentioned that a similar approach is followed in many other international standards such as the North American Standard ACI 318:2011, the Canadian
Standard CSA A23.1:2009, the Australian Standard AS 3600:2001, and
the Indian Standard IS 456-2000. Some exposure classes are defined
Table 1.2 Exposure classes defined in European Standard EN 206-1:2000
Exposure classes
no risk of corrosion or attack
X0
corrosion induced by carbonation
XC1
Dry or permanently wet
XC2
Wet, rarely dry
XC3
Moderate humidity
XC4
Cyclic wet and dry
corrosion induced by chlorides other than from sea water
XD1
Moderate humidity
XD2
Wet, rarely dry
XD3
Cyclic wet and dry
corrosion induced by chlorides from sea water
XS1
Exposed to airborne salt but not in direct contact with sea water
XS2
Permanently submerged
XS3
Tidal, splash, and spray zones
freeze/thaw attack with or without de-icing salts
XF1
Moderate water saturation without de-icing agents
XF2
Moderate water saturation with de-icing agents
XF3
High water saturation without de-icing agents
XF4
High water saturation with de-icing agents or sea water
chemical attack
XA1
Slightly aggressive chemical environment
XA2
Moderately aggressive chemical environment
XA3
Highly aggressive chemical environment