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).
However, it is important to note that the structural stability of the
pyramid is not primarily a result of its shape. The integrity of the
pyramid is intact as long as each of the stones is able to support the
weight of the stone above it. The limestone blocks were taken from a quarry near the build site.
Since the compressive strength of limestone is anywhere from 30 to 250
MPa (MPa = Pa * 10^6), the blocks will not fail under compression.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 stone masons 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.
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