Ad
related to: effects of sulfate in concrete paintingvalspar.com has been visited by 10K+ users in the past month
Search results
Results From The WOW.Com Content Network
Sulfate attack typically happens to ground floor slabs in contact with soils containing a source of sulfates. [2] Sulfates dissolved by ground moisture migrate into the concrete of the slab where they react with different mineral phases of the hardened cement paste. The attack arises from soils containing SO 2−
As a consequence, even concrete containing low-C 3 A sulfate-resisting Portland cement may be affected. [9] TSA is sometimes easily recognizable on the field when examining the altered concrete. TSA-affected concrete becomes powdery and can be dug with a scoop, or even scrapped with the fingers. Concrete decohesion is very characteristic of TSA.
Corrosion may occur where stale sewage generates hydrogen sulfide gas into an atmosphere containing oxygen gas and high relative humidity. There must be an underlying anaerobic aquatic habitat containing sulfates and an overlying aerobic aquatic habitat separated by a gas phase containing both oxygen and hydrogen sulfide at concentrations in excess of 2 ppm.
This reaction is expansive, and can disrupt mature concrete. Where concrete is to be placed in contact with, for example, sulfate-laden ground waters, either a "sulfate-resisting" cement (with low levels of tricalcium aluminate) is used, or slag is added to the cement or to the concrete mix. The slag contributes sufficient aluminium to suppress ...
When a paint coating is applied on a metallic surface contaminated with soluble salts, an osmotic blistering process takes place (Figure 8.10). Osmosis is the spontaneous net movement of solvent molecules (water) through a semipermeable membrane (coating film) into a region of higher solute concentration (the salt contaminated substrate).
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Donate
Traditional painting materials and processes can have harmful effects on the environment, including those from the use of lead and other additives. Measures can be taken to reduce its environmental effects, including accurately estimating paint quantities so waste is minimized, and use of environmentally preferred paints, coating, painting ...
The solvent also modifies the curing rate and viscosity of the paint in its liquid state. There are two types of paint: solvent-borne and water-borne paints. Solvent-borne paints use organic solvents as the primary vehicle carrying the solid components in a paint formulation, whereas water-borne paints use water as the continuous medium.