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The formation of fissures in the concrete cover above the reinforcement bars represents a preferential pathway for the ingress of water and aggressive agents such as CO 2 (lowering of pH around the rebar) and chloride anions (pitting corrosion) into concrete. The physical formation of cracks therefore favors the chemical degradation of concrete ...
In the UK, well built modern houses include damp proofing in the form of a synthetic damp-proof course (DPC), about 15 cm (6") above ground level, to act as a barrier through which water cannot pass. Slate or "engineering bricks" with a low porosity were often used for the first few courses above ground level, and these can help minimise the ...
Bacterial activity in sewers – anaerobic sulfate reduction at work in the organic-rich sludges accumulated under water in the conduits produces hydrogen sulfide gas (H 2 S). After its released in the air of the galleries, H 2 S is further oxidized into sulfuric acid by atmospheric oxygen.
Air entrainment in concrete is the intentional creation of tiny air bubbles in a batch by adding an air entraining agent during mixing. A form of surfactant (a surface-active substance that in the instance reduces the surface tension between water and solids) it allows bubbles of a desired size to form.
The South Coast Air Quality Management District's governing board voted 9-1 to effectively phase out certain kinds of natural-gas-fired water-heating equipment in homes and businesses across its ...
The city’s water company issued a boil water notice on Friday to the more than 600,000 people it serves because low pressure in the system and breaks in water mains could allow harmful bacteria ...
A water pipe that burst overnight and flooded Duke University Hospital continued to cause problems Friday, with ambulances being diverted to other hospitals in the region. A chilled water pipe ...
A rupture disc (burst) Pressure-effect acting at a rupture disc A rupture disc, also known as a pressure safety disc, burst disc, bursting disc, or burst diaphragm, is a non-reclosing pressure relief safety device that, in most uses, protects a pressure vessel, equipment or system from overpressurization or potentially damaging vacuum conditions.