History of Structural Engineering

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Structural engineering dates back to 2700 B.C.E. when the step pyramid for Pharaoh Djoser was built by Imhotep, the first engineer in history known by name. Pyramids were the most common major structures built by ancient civilizations because the structural form of a pyramid is inherently stable and can be almost infinitely scaled (as opposed to most other structural forms, which cannot be linearly increased in size in proportion to increased loads).

The structural stability of the pyramid, whilst primarily gained from its shape, relies also on the strength of the stone from which it is constructed, and its ability to support the weight of the stone above it.  The limestone blocks were often taken from a quarry near the build site and have a compressive strength from 30 to 250 MPa (MPa = Pa * 10^6). Therefore, the structural strength of the pyramid stems from the material properties of the stones from which it was built rather than the pyramid's geometry.

Throughout ancient and medieval history most architectural design and construction was carried out by artisans, such as stonemasons and carpenters, rising to the role of master builder. No theory of structures existed, and understanding of how structures stood up was extremely limited, and based almost entirely on empirical evidence of 'what had worked before'. Knowledge was retained by guilds and seldom supplanted by advances. Structures were repetitive, and increases in scale were incremental.

No record exists of the first calculations of the strength of structural members or the behavior of structural material, but the profession of structural engineer only really took shape with the Industrial Revolution and the re-invention of concrete (see History of Concrete. The physical sciences underlying structural engineering began to be understood in the Renaissance and have since developed into computer-based applications pioneered in the 1970s.

Civil Engineering has been an aspect of life since the beginnings of human existence. The earliest practices of Civil engg may have commenced between 4000 and 2000 BC in Ancient Egypt and Mesopotamia (Ancient Iraq) when humans started to abandon a nomadic existence, thus causing a need for the construction of shelter. During this time, transportation became increasingly important leading to the development of the wheel and sailing.

Until modern times there was no clear distinction between civil engg and architecture, and the term engineer and architect were mainly geographical variations referring to the same person, often used interchangeably. The construction of Pyramids in Egypt (circa 2700-2500 BC) might be considered the first instances of large structure constructions

Ancient historic civil engineering constructions include the Qanat water management system (the oldest older than 3000 years and longer than 71 km,) the Parthenon by Iktinos in Ancient Greece (447-438 BC), the Appian Way by Roman engineers (c. 312 BC), the Great Wall of China by General Meng T’ien under orders from Ch’in Emperor Shih Huang Ti (c. 220 BC) and the stupas constructed in ancient Sri Lanka like the Jetavanaramaya and the extensive irrigation works in Anuradhapura. The Romans developed civil structures throughout their empire, including especially aqueducts, insulae, harbours, bridges, dams and roads.

Other remarkable historical structures are Sennacherib's Aqueduct at Jerwan built in 691 BC; Li Ping's irrigation projects in China (around 220 BC); Julius Caesar's Bridge over the Rhine River built in 55 BC, numerous bridges built by other Romans in and around Rome(e.g. the pons Fabricius); Pont du Gard (Roman Aqueduct, Nimes, France) built in 19 BC; the extensive system of highways the Romans built to facilitate trading and (more importantly) fast manoeuvring of legions; extensive irrigation system constructed by the Hohokam Indians, Salt River, AZ around 600 AD; first dykes defending against high water in Friesland, The Netherlands around 1000 AD; El Camino Real - The Royal Road, Eastern Branch, TX and Western Branch, NM (1500s AD).