Influence of pigment Solutions on color stability and surface properties in low-shrinkage and conventional composites

Luciana L Meneghel1, Ana Pp Fugolin2, Sandrine B Berger1

  • 1Universidade Pitágoras Unopar-UNOPAR, Faculdade de Odontología, Departamento de Odontología Restauradora, Londrina, PR, Brasil.

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Shrinkage in concrete is primarily due to water loss from evaporation, hydration of cement, or carbonation, leading to a reduction in volume. The volumetric contraction results in volumetric strain in concrete. However, in practice, shrinkage is measured as linear strain, which is one-third of the volumetric strain.
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Carbonation Shrinkage01:24

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Drying Shrinkage01:21

Drying Shrinkage

When hardened concrete is exposed to air with a relative humidity of less than 100 percent, it begins to lose the free water within its capillaries. As this water evaporates, the water initially adsorbed onto the calcium silicate hydrates migrates towards these now empty spaces and eventually evaporates as well. Over time, as more water leaves, the volume of the concrete decreases, a phenomenon known as drying shrinkage.
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