The Many Uses of Sand and Aggregates in Construction

1. The Many Uses of Sand and Aggregates in Construction In the world of construction, it’s easy to take sand and aggregates for granted, but they have so many uses that it’s hard to keep track of them all. Not only are they essential in concrete building projects, they also have applications in asphalt and concrete work as well as landscaping and garden design. Let’s take a look at some of the more popular uses of sand and aggregates in the construction world today. Gravel and Crushed Stone When you’re building a driveway, adding onto your home or building anything concrete, gravel is a popular construction material. It has two primary uses: to act as an aggregate (it’s mixed with cement and sand), and to provide drainage for rainwater. As a non-engineered fill, it can be used for low-impact development projects like ball fields. Gravel comes in three sizes: small (about one-sixteenth of an inch), coarse (roughly half an inch) and large (roughly 1/4 inch). When crushed, it’s called crushed stone. This rock is popular for curbing as well as landscaping. Residential uses It’s no secret that homes can be built without a ton of sand or aggregates. Even so, most building contractors use them regularly. Depending on where you live, you may be familiar with these terms; they refer to soil-like materials made up primarily of crushed stone, gravel or dirt. These products are key ingredients in concrete and asphalt—the stuff used to build roads—as well as cement blocks and bricks (which get mixed with water and air to form mortar). But those aren’t their only uses! Imports, exports and consumption How is sand used throughout the world? As you can imagine, it’s most heavily consumed right here at home. The U.S. is both a huge importer and exporter of sand, bringing in about $8 billion worth each year from countries like Canada, Mexico, Japan, Morocco and other countries around the world (the top five export destinations for U.S.-made sand are Canada ($4.4 billion), Mexico ($1.6 billion), Germany ($0.74 billion), China ($0.57 billion) and South Korea ($0.45 billion)). We also export a ton domestically: In fact, it’s estimated that we export more sand than any other country on Earth (with sales to China coming in second). And why not? How much is used every year? Globally, it’s estimated that over 6.3 billion tons of sand are extracted every year for use in construction. This is an incredibly significant number; not only because sand is a natural resource, but also because extracting these resources can have negative effects on both our environment and our health. The amount used varies from country to country depending on several factors like population density, climate conditions, etc., but no matter what – most

2. countries are using more than they should be. It’s important to note here that concrete isn’t just made up of sand; cement is mixed with water to create concrete. Where does it come from? Well, rocks are made from minerals that are created when heat and pressure fuse elements like silicon, aluminum, iron, calcium, potassium, sodium, zinc and titanium together. When it rains on bedrock or an eroding cliff face (as it often does at construction sites), water washes these minerals down to rivers which eventually dump them out into oceans. Over time (millions of years) currents push these eroded rocks around so they eventually form beaches on coastlines all over the world. As your architect will tell you--sand and gravel make up approximately 65% to 75% percent of construction concrete’s aggregate. The other 25% is used to reinforce concrete’s strength (rebar). Why do we need to use concrete for road building? We’ve all seen pictures or have heard stories about new roads being built with concrete. Why do they use it? Concrete is stronger than asphalt, lasts longer, and is more environmentally friendly to produce. Asphalt often has up to 40% recycled material in it, whereas concrete contains zero recycled material. Concrete also has a much higher tensile strength—or resistance to breakage—than asphalt does, which means that you can drive on it at faster speeds without worrying about potholes forming and causing problems for drivers. Finally, concrete roads require less maintenance throughout their lifetimes. What are aggregate fines? Aggregate fines are tiny particles (1/16 inch or smaller) that add volume to soils. They're a key component of concrete, asphalt, plaster, stucco, grout and plasterboard. To make aggregates into aggregate fines, simply screen them through a 0.125-inch screen to separate them from coarser materials such as sand. A powerful magnet will remove metal particles before you put anything on a conveyor belt for processing. After passing through that metal detector, these aggregate fines can then be shipped off by rail car or truck; crushed down even further at a plant; or used as they are—as ready-made aggregate fines—by construction companies all over North America...and beyond! What are the different types of aggregate rocks? The different types of rocks that are used as aggregates are granite, limestone, sandstone, slate, pebbles and gravel. Granite is a hard rock mainly composed by feldspar minerals. Limestone consists mainly by calcium carbonate. Slate is a soft rock made up mostly by clay minerals. Pebbles are basically rounded rocks having medium size with thin to thick weathering crust on it. Gravel is small to medium sized rounded rock fragments with thick weathering crust on it. Generally boulders or cobbles are not considered as aggregate but they can be used as aggregate rocks if their size is reduced before mixing into concrete mixes like road works etc... In some cases boulders or cobbles can be crushed using jaw crusher for use as aggregates for concrete purposes.

3. About granulated blast furnace slag (GBS) concrete products … When mixed with sand, GBS concrete products can be used for footings, foundations, curbs and gutters. The GBS concrete product replaces 30 to 40 percent of fine aggregate with mineral slag. Because slag has different physical properties than crushed stone or sand, mixing it with cement makes a tough but workable material that resists weathering. It also reduces your overall costs because you need less cement to hold it together ... As a building material that combines economic value, durability and sustainable properties into one package, granulated blast furnace slag (GBS) concrete has significant benefits ... For example, they are non-combustible which makes them valuable additions to buildings near wooded areas or close to fuel tanks.