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DPC visible between concrete foundation and brickwork. Damp proofing is defined by the American Society for Testing and Materials (ASTM) as a material that resists the passage of water with no hydrostatic pressure. [1] Waterproof is defined by the ASTM as a treatment that resists the passage of water under pressure. [1]
Polished concrete may be considered a form of sustainable design flooring, if less material is used than in comparable types of flooring. [citation needed] Polished concrete floors have the following advantages: low-maintenance [7] – polished concrete is easily maintained with the use of clean water or a neutral pH cleaner. The application of ...
The Ellipse, sometimes referred to as President's Park South, is a 52-acre (21 ha) park south of the White House fence and north of Constitution Avenue and the National Mall in Washington, D.C., United States. The Ellipse is also the name of the five-furlong (1.0 km) circumference street within the park.
Dalecarlia Water Treatment Plant, Washington, D.C. Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment.
Portland cement has been used to treat more contaminated material than any other S/S binding agent because of its ability to bind free liquids, reduce permeability, encapsulate hazardous materials, and reduce the toxicity of certain contaminants. Lime can be used to adjust the pH of the substance of drive off water by using high heats of hydration.
Oxidation of pyrite in clay formations in contact with concrete – this produces sulfuric acid which reacts with concrete. 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).
When atmospheric carbon dioxide (CO 2), or carbonate ions (HCO − 3, CO 2− 3 dissolved in water) diffuse into concrete from its external surface, they react with calcium hydroxide (portlandite, Ca(OH) 2) and the pH of the concrete pore water progressively decreases from 13.5 – 12.5 to 8.5 (pH of water in equilibrium with calcite).
A concrete slab is a common structural element of modern buildings, consisting of a flat, horizontal surface made of cast concrete. Steel- reinforced slabs, typically between 100 and 500 mm thick, are most often used to construct floors and ceilings, while thinner mud slabs may be used for exterior paving ( see below ).