Parameters for calculation of shrinkage strain

 

The total shrinkage strain is composed of two components, the drying shrinkage strain and the autogenous shrinkage strain. The drying shrinkage strain develops slowly, since it is a

function of the migration of the water through the hardened concrete. The autogenous shrinkage strain develops during hardening of the concrete

There are three options for calculation/input total shrinkage strain:

• No (Consider drying and autogenous shrinkage= No)- shrinkage will not be taken into account in CDD calculation
• Automatic calculation (Consider drying and autogenous shrinkage = Auto), where shrinkage strain is calculated according to EN 1992-1-1, chapter 3.1.4(6) for following input parameters:

  • Relative humidity

  • Age of concrete at beginning of drying shrinkage

  • Age of concrete at moment considered

  

  Except of these input parameters, automatic calculation of creep coefficient depends on material properties (mean compressive strength of concrete f_cm,characteristic compressive cylinder strength f_ck ,type of cement), cross-section parameters (cross-sectional area A_c and the perimeter of the member in contact with the atmosphere u)

• User input (Consider drying and autogenous shrinkage = User value) and user can input directly value of total shrinkage strain

automatic calculated shrinkage strain can be in each section of 1D member or in each element of 2D member different, because cross-sectional properties and material properties can be different in each section/member (haunch, arbitrary member, 2D member with variable thickness...)

type of shrinkage strain and input parameters can be defined separately for each 1D and 2D member via Setting per member (1D concrete data and 2D concrete data)