Concrete is a construction material composed of cement In the most general sense of the word, a cement is a binder, a substance which sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term "opus caementicium" to describe masonry which resembled concrete and was made from crushed rock with burnt lime as binder (commonly Portland cement Portland cement is the most common type of cement in general use around the world, because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout. It is a fine powder produced by grinding Portland cement clinker (more than 90%), a limited amount of calcium sulfate which controls the set time, and up to 5% minor) as well as other cementitious materials such as fly ash Fly ash is one of the residues generated in the combustion of coal. Fly ash is generally captured from the chimneys of coal-fired power plants, and is one of two types of ash that jointly are known as coal ash; the other, bottom ash, is removed from the bottom of coal furnaces. Depending upon the source and makeup of the coal being burned, the and slag cement Ground granulated blast furnace slag is obtained by quenching molten iron slag (a by-product of iron and steel making) from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder, aggregate Construction aggregate, or simply "aggregate", is a broad category of coarse particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are a component of composite materials such as concrete and asphalt concrete; the aggregate serves as reinforcement (generally a coarse aggregate such as gravel Gravel is rock that is of a specific particle size range. Specifically, it is any loose rock that is larger than two millimeters in its smallest dimension (about 1/12 of an inch) and no more than 64 mm (2.5 in). The next smaller size class in geology is sand, which is >0.0625 to 2 mm (0.0025 to 0.0787 in) in size. The next larger size is cobble,, limestone Limestone is a sedimentary rock composed largely of the mineral calcite . The deposition of limestone strata is often a by-product and indicator of biological activity in the geologic record. Calcium (along with nitrogen, phosphorus, and potassium) is a key mineral to plant nutrition: soils overlying limestone bedrock tend to be pre-fertilized, or granite Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite has a medium to coarse texture, occasionally with some individual crystals larger than the groundmass forming a rock known as porphyry. Granites can be pink to dark gray or even black, depending on their chemistry and mineralogy. Outcrops of granite tend to, plus a fine aggregate such as sand Sand is a naturally occurring granular material composed of finely divided rock and mineral particles), water Water is the most abundant molecule on Earth's surface, constituting about 75% of the Earth's surface. In nature it exists in liquid, solid, and gaseous states. It is in dynamic equilibrium between the liquid and gas states at standard temperature and pressure. At room temperature, it is a nearly colorless with a hint of blue, tasteless, and, and chemical Chemistry (from Egyptian kēme , meaning "earth") is the science concerned with the composition, behavior, structure, and properties of matter, as well as the changes it undergoes during chemical reactions. It is a physical science for studies of various atoms, molecules, crystals and other aggregates of matter whether in isolation or admixtures. The word concrete comes from the Latin word "concretus" (meaning compact or condensed), the past participle of "concresco", from "com-" (together) and "cresco" (to grow).
Concrete solidifies and hardens after mixing with water and placement due to a chemical process A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.. They are studied by chemists under a field of science called chemistry. It can be either spontaneous that is requiring no input of energy or non-spontaneous, that often comes about only after input of some form of energy, viz. heat, known as hydration Mineral hydration is an inorganic chemical reaction where water is added to the crystal structure of a mineral, usually creating a new mineral, usually called a hydrate. The water reacts with the cement, which bonds the other components together, eventually creating a stone-like material. Concrete is used to make pavements A sidewalk , pavement (British English, South African English and Philadelphia dialect), footpath (Australian English, Irish English, Indian English, Pakistani English and New Zealand English), platform (chiefly Indian English) or footway (Engineering term) is a path for pedestrians that is situated alongside a road or a paved pathway (such as a, architectural structures The structure may be permanent. Typical examples include buildings and nonbuilding structures such as bridges, dams, electricity pylons, and radio masts, foundations A foundation is a structure that transfers loads to the earth. Foundations are generally broken into two categories: shallow foundations and deep foundations, motorways Motorways are identical to freeways as a road type, and comparable to the United States's Interstate Highways as a classification/roads A road is an identifiable route, way or path between places. Roads are typically smoothed, paved, or otherwise prepared to allow easy travel; though they need not be, and historically many roads were simply recognizable routes without any formal construction or maintenance, bridges A bridge is a structure built to span a valley, road, body of water, or other physical obstacle, for the purpose of providing passage over the obstacle. Designs of bridges vary depending on the function of the bridge and the nature of the terrain where the bridge is constructed/overpasses An overpass is a bridge, road, railway or similar structure that crosses over another road or railway. An overpass structure is one that carries a higher capacity road above a lower capacity road, whereas a structure that permits a lower capacity road to travel above a larger capacity road is an underpass.[citation needed] Capacity is determined, parking Parking is the act of stopping a vehicle and leaving it unoccupied for more than a brief time. Parking on one or both sides of a road is commonly permitted, though often with restrictions. Parking facilities are constructed in combination with most buildings, to facilitate the coming and going of the buildings' users structures, brick A brick is a block of ceramic material used in masonry construction, usually laid using mortar/block walls and footings for gates, fences A fence is a freestanding structure designed to restrict or prevent movement across a boundary. It is generally distinguished from a wall by the lightness of its construction: a wall is usually restricted to such barriers made from solid brick or concrete, blocking vision as well as passage and poles.
Concrete is used more than any other man-made material in the world.[1] As of 2006, about 7.5 cubic kilometres of concrete are made each year—more than one cubic metre for every person on Earth.[2] Concrete powers a US $ The United States dollar is the unit of currency of the United States. The U.S. dollar is normally abbreviated as the dollar sign, $, or as USD or US$ to distinguish it from other dollar-denominated currencies and from others that use the $ symbol. It is divided into 100 cents (200 half-cents prior to 1857)35-billion industry which employs more than two million workers in the United States The United States of America is a federal constitutional republic comprising fifty states and a federal district. The country is situated mostly in central North America, where its forty-eight contiguous states and Washington, D.C., the capital district, lie between the Pacific and Atlantic Oceans, bordered by Canada to the north and Mexico to the alone.[citation needed] More than 55,000 miles (89,000 km) of highways A highway is a main road for travel by the public between important destinations, such as cities and states. Highway designs vary widely and can range from a two-lane road without margins to a multi-lane, grade separated motorway. In English and U.S. law, the word "highway" is used to denote any public way used for travel, whether major in the United States are paved with this material. Reinforced concrete Reinforced concrete is concrete in which steel reinforcement bars , plates or fibers have been incorporated to strengthen a material that would otherwise be brittle and prestressed concrete Prestressed concrete is a method for overcoming the concrete's natural weakness in tension. It can be used to produce beams, floors or bridges with a longer span than is practical with ordinary reinforced concrete. Prestressing tendons are used to provide a clamping load which produces a compressive stress that offsets the tensile stress that the are the most widely used modern kinds of concrete functional extensions.
Straits Times
The concrete of Kallang drainage canal will be torn up and the water way will be brought into the park as a meandering river with gentle slopes and plant ...
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A color matched concrete counter
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ue, 29 Sep 2009 07:53:57 GM
Before radar, these experimental . concrete. sound mirrors were used to try and detect planes crossing the channel.
Q. Concrete nouns are nouns we can touch, such as apples. However, paper is a common noun. We can touch paper why isnt it a concrete noun or a common concrete noun?
Asked by Future - Wed Mar 26 20:35:45 2008 - - 3 Answers - 0 Comments
A. I'm an ESL teacher. Your question is confusing. Here is some information about nouns. There are concrete nouns that refer to something that you touch, such as your example of an apple, but there are abstract nouns, such as "love", "joy", things that can't be touched. However, both "apples" and "love" are common nouns, versus proper nouns which always take a capital letter and are the names of things or people: John, Paris, Tuesday. You are probably confusing the terms "count nouns" and "non-count" nouns, (also called "countable" and "uncountable"). Apples are count nouns because you can count them. Paper as a substance is a non-count noun. You don't count paper, you count sheets of paper, or packages of paper. Other non-count nouns… [cont.]
Answered by superwoman - Wed Mar 26 21:08:44 2008
