Abstract
Tension softening and cracking due to non-uniform shrinkage is investigated in a parametric study and the relation between shrinkage as a material property and the dimensional change of drying specimens is analysed. It is found that regions with tensile strains causing softening or cracking are developed in the early stages of drying. The shrinkage of a drying concrete specimen is always less than or equal to the true material shrinkage, but for normal concrete and drying situations which occur in practice the difference is small compared with the final shrinkage.
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Abbreviations
- C :
-
Diffusivity with respect to moisture concentration
- E :
-
Elastic modulus
- E T :
-
Softening modulus
- F O :
-
Fourier number (dimensionless time), defined in Equation 1
- l ch :
-
Characteristic length of the material
- l s :
-
Spacing between localized cracking zones
- R :
-
Half-thickness of plate, radius of cylinder
- s :
-
Drying shrinkage in the material corresponding to a moisture change betweenw 0 andw 1
- w :
-
Specific moisture content
- w 0 :
-
Initial value ofw
- w 1 :
-
Value ofw when drying is completed
- x :
-
Position coordinate
- ∈l :
-
Relative length change of cylinder or plate
- ∈p :
-
Strain at maximum tensile stress (see Fig. 3)
- ∈s :
-
Shrinkage strain
- \(\bar \in _s \) :
-
‘Mean’ free shrinkage
- θ:
-
Dimensionless water content, defined in Equation 1
- ξ:
-
x/R, dimensionless position coordinate
- σe :
-
Stress due to external load
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Thelandersson, S., Mårtensson, A. & Dahlblom, O. Tension softening and cracking in drying concrete. Materials and Structures 21, 416–424 (1988). https://doi.org/10.1007/BF02472321
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DOI: https://doi.org/10.1007/BF02472321