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Much agricultural pollution is exacerbated by surface runoff, leading to a number of down stream impacts, including nutrient pollution that causes eutrophication. In addition to causing water erosion and pollution, surface runoff in urban areas is a primary cause of urban flooding , which can result in property damage, damp and mold in ...
In undisturbed areas with natural subsurface drainage, soil and rock fragments choke karst openings thereby being a self-limitation to the growth of openings. [13]: 189–190, 196 The undisturbed karst drainage system becomes balanced with the climate so it can drain the water produced by most storms. However, problems occur when the landscape ...
Contact with wet concrete can cause skin chemical burns due to the caustic nature of the mixture of cement and water (including rainwater). Indeed, the pH of fresh cement water is highly alkaline due to the presence of free potassium and sodium hydroxides in solution (pH ~ 13.5). Eyes, hands and feet must be correctly protected to avoid any ...
It is the considerable forces internally created by the expansion of the iron corrosion products (about 6 – 7 times less dense than metallic iron, so 6 – 7 times more voluminous) that cause the cracks in the concrete matrix and destroy reinforced concrete. In the absence of iron (and without some harmful chemical degradation reactions also ...
Storm drain grate on a street in Warsaw, Poland Storm drain with its pipe visible beneath it due to construction work. A storm drain, storm sewer (United Kingdom, U.S. and Canada), highway drain, [1] surface water drain/sewer (United Kingdom), or stormwater drain (Australia and New Zealand) is infrastructure designed to drain excess rain and ground water from impervious surfaces such as paved ...
As for any concrete repair, the state-of-the-art rules must be followed. After this cleaning step, the cementitious material is applied to the saturated-surface-dry substrate using either: Low pressure wet spray: this method is the more common because it does not produce dust and virtually no material is lost by rebound.
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Drainage options for the construction industry include: Point drainage, which intercepts water at gullies (points). Gullies connect to drainage pipes beneath the ground surface, so deep excavation is required to facilitate this system. Support for deep trenches is required in the shape of planking, strutting or shoring.