Search results
Results from the WOW.Com Content Network
Concrete carbonation can be visually revealed by applying a phenolphthalein solution over the fresh surface of a concrete samples (concrete core, prism, freshly fractured bar). Phenolphthalein is a pH indicator , whose color turns from colorless at pH < 8.5 to pink-fuchsia at pH > 9.5.
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 ...
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
The good news for the milkvetch plant is that they usually need wildfire to sprout — meaning dormant seeds now have a massive new habitat for a new crop of the rare shrub.
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.
But because the concrete cancer issue keeps coming up, White and Lauer say in their letter that the public needs to know whether Kauffman is in as bad shape as the team has said it is.
Jennifer Aniston does not abide by one popular health mantra. "No pain, no gain. That's not true at all," the actress, 55, tells PEOPLE in an exclusive interview. "You can actually have gain with ...
Degrading concrete has been the focus of many studies and the most obvious sign is calcium-rich leachate seeping from a concrete structure. [5] [6] [7]Calthemite stalactites can form on concrete structures and "artificial caves" lined with concrete (e.g. mines and tunnels) significantly faster than those in limestone, marble or dolomite caves.