Influence of wall effect on drying shrinkage of self-compacting concrete

The time-consuming nature of conventional shrinkage tests—which often extend over a year to approach ultimate shrinkage values and enable reliable extrapolation to structural scales—necessitates the development of accelerated approaches. This study investigates the shrinkage and moisture loss of specimens smaller than the recommended https://www.w3.org/1998/Math/MathML" display="inline"> 75 × 75 m m or https://www.w3.org/1998/Math/MathML" display="inline"> 100 × 100 m m prisms. In the experimental part, prismatic specimens of several sizes are prepared conventionally by casting or wet-cutting from a larger block of self-compacting concrete to mitigate the wall-effect caused by the mold. In the first 100 days of the experiment, behavior contradicting engineering expectations was observed, showing that the cut-out specimens tend dry and shrink faster and more. One-way coupled hygro-mechanical model was developed for both types of specimens. If the cut-out specimens are assumed as homogeneous, the modeling approach can accurately capture moisture loss, shrinkage evolution, and the development of internal relative humidity. The data support the credibility of the non-linear shrinkage coefficient recently introduced in the MPS theory. However, accurately reproducing the trends observed in the cast specimens remains challenging with the present modeling approach, indicating complexities that warrant further investigation.