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Primary efflorescence is named such, as it typically occurs during the initial cure of a cementitious product. It often occurs on masonry construction, particularly brick, as well as some firestop mortars, when water moving through a wall or other structure, or water being driven out as a result of the heat of hydration as cement stone is being formed, brings salts to the surface that are not ...
Example of secondary efflorescence in parking garage exposed to diluted road salt from vehicles entering the garage during winter. When water flows through cracks present in concrete, water may dissolve various minerals present in the hardened cement paste or in the aggregates, if the solution is unsaturated with respect to them.
A fairly well-defined reaction front can often be observed in thin sections; ahead of the front the concrete is normal, or near normal. Behind the reaction front, the composition and the microstructure of concrete are modified. These changes may vary in type or severity but commonly include: Extensive cracking; Expansion
Efflorescence is usually the result of mineral solutions in the capillary channels being drawn to the surface. If the water evaporates, the minerals remain as the so-called efflorescence. It also can be the result of chemical reaction; if badly prepared cement-based mortar is applied to maintain the stone in position, free calcium hydroxide may ...
You don’t want to add heavy chemicals that could cause issues with your skin, because the pores will get clogged up. Concrete pores work like the pores on your face, and you want to keep them clean.
Concrete has a total embodied energy of 1.69 GJ/tonne, lower per unit mass than most common building materials besides wood. However, concrete structures often have high masses, so this comparison is not always directly relevant to decision making. Additionally, this value is based only on mix proportions of up to 20% fly ash.
The concrete industry uses calcium stearate for efflorescence control of cementitious products used in the production of concrete masonry units i.e. paver and block, as well as waterproofing. [3] In paper production, calcium stearate is used as a lubricant to provide good gloss, preventing dusting and fold cracking in paper and paperboard ...
Processing can create layers in materials which can fail by delamination. In concrete, surfaces can flake off from improper finishing. If the surface is finished and densified by troweling while the underlying concrete is bleeding water and air, the dense top layer may separate from the water and air pushing upwards. [8]