Autogenous Shrinkage

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. When concrete is still in its plastic state, it can undergo a decrease in volume by about 1% of its absolute volume. This decrease is known as plastic shrinkage. It arises either...

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. A portion of this drying shrinkage can be reversed; if the concrete is...

Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage. The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...

In order to understand the spatial development of polymerization shrinkage stress in dental resin-composite restorations, Digital Image Correlation was used to provide full-field displacement/strain measurement of restored model glass cavities by correlating images of the restoration taken before and after polymerization.

In inventory-based businesses, profitability often depends on more than just sales volume or procurement efficiency. Hidden costs tied to inventory management—specifically shrinkage, obsolescence, and holding costs—can significantly erode margins if left unmanaged.Shrinkage occurs when inventory is lost due to theft, damage, or administrative errors. Even with advanced tracking systems, discrepancies remain a persistent issue, especially in retail. Regular audits, employee training, and...