EN 680:2005

Foreword
1 Scope
2 Normative references
3 Principle
4 Apparatus
5 Test specimens
  5.1 Sample
  5.2 Shape and size of the test specimens
  5.3 Number of test specimens
  5.4 Preparation of test specimens
  5.5 Measurement of dimensions of test specimens and
      determination of their volume
  5.6 Conditioning of test specimens
6 Testing procedure
  6.1 Drying storage in a climate at (20 +/- 2) degree C and
      (45 +/- 5) % relative humidity and determination of
      length changes and variations of mass
  6.2 Drying of test specimens at (105 +/- 5) degree C
7 Test results
  7.1 Calculation of relative length change
  7.2 Calculation of moisture content
  7.3 Determination of the conventional reference value of
      drying shrinkage
  7.4 Determination of the total value of drying shrinkage
  7.5 Calculation of the dry density
8 Test report

This Euopean Standard specifies a method for measuring the relative length changes due to drying (drying shrinkage) of autoclaved aerated concrete manufactured according to EN 771-4 or prEN 12602. The shrinkage characteristics determined according to this method are the following: The conventional reference value of drying shrinkage is the relative length change between two specified moisture contents. The total value of drying shrinkage is the relative length change due to drying from the saturated state until reaching constant length under specified climatic conditions. Other drying shrinkage values may be determined between other parameters to meet other specified national requirements.