Construction sand and gravel is used to make concrete, for road construction, for mixing with asphalt, as construction fill, and in the production of construction materials like concrete blocks, bricks, and pipes. Sand and gravel can also used to make roofing shingles; on icy roads in the winter for enhanced traction; as landscape material; on driveways or parking lots; and also for water filtration.
Sand itself comes in various sizes of grain. It is used for everyday purposes and comes from many sources. It is washed, safe and non-toxic, dried and filtered sand which conforms to safety standard BS EN For outdoor sports and play areas sand can be indispensable.
For example, landing on cushioning sand will be softer than a paving stone. Sand can be laid beneath and between paving to facilitate a smooth level surface for the slabs to sit on and support for hard landscaping.
If you wish to have a Zen garden which is peaceful, organised and perfect for contemplation sand is a vital landscaping material. Raked sand resembles rippling water and has great allure.
Pea gravel is not expensive but it has several uses. Tile manufacturing companies have mixed sand and lime together to make a special brick to use as a building material. Silica rich sand is also exported to major cement manufacturers. There are so many different uses for sand, from leisure activities to commercial uses; the list gets longer every day.
Commercial grade sand is also used in water filtration and has even been used to line animal enclosures at the zoo. Not only does sand have so many commercial uses, it is an inexpensive way to make play areas safer. This can be accomplished by spreading a layer of sand about a foot deep under swings, slides, trampolines, and any other area where safety is an issue.
The mess will solidify and can then be swept up. Sand also works on oil spills in the driveway or garage. Sprinkle sand onto the spill, allow it to set, and then sweep up the mess. If you like to barbecue on a charcoal grill, keep a small bucket or other container of sand handy to put out flames.
The demand for that material is so intense that around the world, riverbeds and beaches are being stripped bare, and farmlands and forests torn up to get at the precious grains.
And in a growing number of countries, criminal gangs have moved in to the trade, spawning an often lethal black market in sand. The main driver of this crisis is breakneck urbanisation. Every year there are more and more people on the planet, with an ever growing number of them moving from the rural countryside into cities, especially in the developing world.
Across Asia, Africa, and Latin America, cities are expanding at a pace and on a scale far greater than any time in human history. The number of people living in urban areas has more than quadrupled since to some 4. Smoothed by the wind, sand in deserts like the Sahara, which cover huge swathes of the planet, do not lock together well in concrete Credit: Alamy. Creating buildings to house all those people, along with the roads to knit them together, requires prodigious quantities of sand.
In India, the amount of construction sand used annually has more than tripled since , and is still rising fast. China alone has likely used more sand this decade than the United States did in the entire 20th Century. There is so much demand for certain types of construction sand that Dubai, which sits on the edge of an enormous desert, imports sand from Australia.
From California to Hong Kong, ever-larger and more powerful dredging ships vacuum up millions of tonnes of sand from the sea floor each year, piling it up in coastal areas to create land where there was none before. Lagos, the largest city in Nigeria, is adding a 2,acre 9. China, the fourth-largest nation on Earth in terms of naturally occurring land, has added hundreds of miles to its coast, and built entire islands to host luxury resorts. This new real estate is valuable, but it often incurs steep costs.
Ocean dredging has damaged coral reefs in Kenya, the Persian Gulf and Florida. It tears up marine habitat and muddies waters with sand plumes that can affect aquatic life far from the original site.
Fishermen in Malaysia and Cambodia have seen their livelihoods decimated by dredging. In China, land reclamation has wiped out coastal wetlands, annihilated habitats for fish and shorebirds, and increased water pollution. To create more space for its nearly six million residents, the jam-packed city-state has built out its territory with an additional 50 sq miles sq km of land over the past 40 years , almost all of it with sand imported from other countries.
The collateral environmental damage has been so extreme that neighbouring Indonesia, Malaysia, Vietnam, and Cambodia have all restricted exports of sand to Singapore. Most of it built with gargantuan amounts of sand. Sand is extracted on an industrial scale from rivers, lakes and beaches around the world to meet the global demand Credit: Getty Images. Mining sand to use in concrete and other industrial purposes is, if anything, even more destructive.
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