History of Civil Engineering



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History of Civil Engineering



Pre-18th Century Civil Engineering

Civil engineering began in 4000 and 2000 BC in Egypt during the times of the creation of the pyramids and with the increased need for transportation of goods, materials, and supplies for people and construction. Major structures like the Ancient Wall of China and the Pyramids were constructed on the basis of ancient civil engineering techniques that form the basis of what we use today. They started creating aqueducts, dams, and vast empires for protection of their people and commodities. Civil engineering was a chiefly applied in a military manner after major civilizations began appearing. Engineers used the principles of civil engineering to construct catapults, towers, and small arms and instruments for them to use in battle. They als0o traveled with armies to construct roads, bridges, and other forms of transportation to assist in the armies’ advance.

18th-20th Century Engineering

It wasn’t until the early to mid 19th century that Civil Engineering was named a separate study from Architecture. In 1819, Norwich University established a separate civil engineering class delineating the difference between architecture, military engineering, and civil engineering. From that point on, many civil engineering societies like the American Society of Civil Engineers were formed in the United States and Europe and the popularity and importance of the study greatly increased.

Modern Civil Engineering

Nowadays, civil engineering is one the most important parts of the engineering field. It is used to create important machinery, buildings, roads, schools, and much more. With recent advancements in technology, modern engineers now have access to programs like CAD and CAM which help them design, create, and test simulations of any type of structure the engineer creates. These programs can save time, money, and labor and greatly increase the efficiency of construction in modern times.

Building materials

Building material is any material which is used for a construction purpose.

Wood

Wood is a product of trees, and sometimes other plants, used for construction purposes when cut or pressed into lumber and such as boards, planks and similar materials. It is a building material and is used in building just about any type of structure in most climates. Wood can be very flexible under loads, keeping strength while bending, and is incredibly strong when compressed vertically. There are many differing qualities to the different types of wood, even among same tree species. This means specific species are better for various uses than others. And growing conditions are important for deciding quality.

Historically, wood for building large structures was used in its unprocessed form as logs. The trees were just cut to the needed length, sometimes stripped of bark, and then notched or lashed into place.

In earlier times, and in some parts of the world, many country homes or communities had a personal woodlot from which the family or community would grow and harvest trees to build with. These lots would be tended to like a garden.

Brick and Block

A brick is a block made of kiln-fired material, usually clay or shale but also may be of lower quality mud, etc. Kilns are thermally insulated chambers, or ovens, in which a controlled temperature regimes are produced. They are used to harden, burn or dry materials. Clay bricks are formed in a moulding (the soft mud method), or in commercial manufacture more frequently by extruding clay through a die and then wire-cutting them to the proper size (the stiff mud process).

Bricks were very popular as a building material in the 1700, 1800 and 1900's. This was probably due to the fact that it was much more flame retardant than wood in the crowding cities, and fairly cheap to produce.

Brickwork masonry is produced when a bricklayer uses bricks and mortar to build up structures such as walls, bridges and chimneys. (Brickwork is also used to finish openings such as doors or windows in buildings made of other materials.) Where the bricks are to remain fully visible, as opposed to being covered up by plaster or stucco, this is known as face-work.

Brickwork

Bricks are laid to expose their ends (Header bricks), or sides (Stretcher bricks). As the work progresses, the bricks are laid in rows called courses. The manner in which the bricks overlap as they are laid up is called the bond. Types of bond include English bond, Flemish Bond, and Herringbone bond, but the most common type of brickwork seen these days is the simple stretcher bond, showing only the long side-surface of the brick.

Because only the outside of finished brickwork is visible, cheaper grades of brick are commonly used for the hidden parts of a wall. The thickness of brickwork is measured in units of brick. If bricks are put down end-to-end with the long side facing you (stretchers) and then another row on top, the wall thickness is half a brick.

Concrete

Concrete is a construction material that consists of cement (commonly Portland cement), aggregate (generally gravel and sand), water and admixtures.

Concrete solidifies and hardens after mixing and placement due to a chemical process known as hydration. The water reacts with the cement, which bonds the other components together, eventually creating a stone-like material. It is used to make pavements, architectural structures, foundations, motorways/roads, overpasses, parking structures, brick/block walls and footings for gates, fences and poles.

Concrete is used more than any other manmade material on the planet.

Cement

Portland cement is the most common type of cement in general usage. It is a basic ingredient of concrete, mortar and plaster. English engineer Joseph Aspdin patented Portland cement in 1824; it was named because of its similarity in colour to Portland limestone, quarried from the English Isle of Portland and used extensively in London architecture. It consists of a mixture of oxides of calcium, silicon and aluminium. Portland cement and similar materials are made by heating limestone (a source of calcium) with clay, and grinding this product (called clinker) with a source of sulfate (most commonly gypsum). When mixed with water, the resulting powder will become a hydrated solid over time.

High temperature applications, such as masonry ovens and the like, generally require the use of a refractory cement; concretes based on Portland cement can be damaged or destroyed by elevated temperatures, but refractory concretes are better able to withstand such conditions.

The water/cement ratio (mass ratio of water to cement) is the key factor that determines the strength of concrete. A lower w/c ratio will yield a concrete which is stronger and more durable, while a higher w/c ratio yields a concrete with a larger slump, so it may be placed more easily.

Agricultural Machinery

Tractor Parts

The tractor drawbar is used to pull various implements. Some tractors have a drawbar which can be attached to the hydraulic linkage. It is not used for heavy implements.

Some tractors have special automatic devices which enable the tractor driver to lift an implement without leaving his seat. These devices are operated hydraulically. In this way much of the weight of the implement is carried on the tractor providing better wheel grip. If an implement is mounted on a hydraulic lift system its weight can be used to increase the pulling power of the tractor: the three-point linkage system transmits much of the weight of' the implement on to the tractor. So one can design lighter implements which need no wheels or heavy drawbars. Mounted implements are easily transported. Hydraulically operated implements can also be attached in front of the tractor.

Using the hydraulic system one can lower of lift the mounted implements. The hydraulic system provides the power for hydraulic motors which are used to drive different machines.

The power-take-off shaft is the driving fогсе for different implements. It can drive irrigation pumps and cultivation machinery. It can provide for the farm when there is a cut in the electricity supply. Some stationary machines are belt driven. Tractors can provide the driving power for this too. Some tractors have a belt pulley mounted on the gear-box and driven by it. Other tractors can have a pulley connected with the power-take-off shaft.



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