Earth structure

Construction is faster with pre-formed adobe or mudbricks, compressed earth blocks, earthbags or fired clay bricks.

It was used in the early civilizations of the Mediterranean, Egypt and Mesopotamia, in the Indus, Ganges and Yellow river valleys, in Central and South America.

[7] The two main technologies are stamped or rammed earth, clay or loam, called pise de terre in French, and adobe, typically using sun-dried bricks made of a mud and straw mixture.

[11] European settlers on the North American Prairies found that the sod least likely to deteriorate due to freezing or rain came from dried sloughs.

It is susceptible to moisture, so must be laid on a course that stops rising dampness, must be roofed or covered to keep out water from above, and may need protection through some sort of plaster, paint or sheathing.

Thick sloping walls made of rammed earth became a characteristic of traditional Buddhist monasteries throughout the Himalayas and became very common in northern Indian areas such as Sikkim.

[28] Their longevity may be explained by the fact that the builders used a relatively dry mix of mortar and aggregate and compacted it by pounding it down to eliminate air pockets.

[1] Mudbricks or Adobe bricks are preformed modular masonry units of sun-dried mud that were invented at different times in different parts of the world as civilization developed.

[31] Adobe bricks are traditionally made from sand and clay mixed with water to a plastic consistency, with straw or grass as a binder.

[49] Pit houses made by Hohokam farmers between 100 and 900 AD, in what is now the southwest of the US, were bermed structures, partially embedded in south-facing slopes.

Other examples of subterranean, semi-subterranean or cliff-based dwellings in both hot and cold climates are found in Turkey, northern China and the Himalayas, and the southwest USA.

[51] A number of Buddhist monasteries built from earth and other materials into cliff sides or caves in Himalayan areas such as Tibet, Bhutan, Nepal and northern India are often perilously placed.

[54] Wattle and daub is an old building technique in which vines or smaller sticks are interwoven between upright poles, and then mud mixed with straw and grass is plastered over the wall.

[58] Generally the walls are not structural, and in interior use the technique in the developed world was replaced by lath and plaster, and then by gypsum wallboard.

[56] European pioneer farmers in the prairies of North America, where there is no wood for construction, often made their first home in a dug-out cave in the side of a hill or ravine, with a covering over the entrance.

[59] The sod strips were piled grass-side down, staggered in the same way as brickwork, in three side-by-side rows, resulting in a wall over 3 feet (0.91 m) thick.

The walled city of Shibam in Yemen, designated a World Heritage Site in 1982, is known for its ten-story unreinforced mud-brick buildings.

[63] The Casa Grande Ruins, now a national monument in Arizona protected by a modern roof, is a massive four-story adobe structure built by Hohokam people between 1200 and 1450 AD.

[66] Huaca de la Luna in what is now northern Peru is a large adobe temple built by the Moche people.

The building went through a series of construction phases, growing eventually to a height of about 32 metres (105 ft), with three main platforms, four plazas and many smaller rooms and enclosures.

Smaller interior buildings are often enclosed by these huge peripheral walls which can contain halls, storehouses, wells and living areas.

[73] Many pre-Columbian Native American societies of ancient North America built large pyramidal earth structures known as platform mounds.

Among the largest and best-known of these structures is Monks Mound at the site of Cahokia in what became Illinois, completed around 1100 AD, which has a base larger than that of the Great Pyramid at Giza.

A levee, floodbank or stopbank is an elongated natural ridge or artificially constructed dirt fill wall that regulates water levels.

[79] After the leveling pad has been laid and the first row of panels has been placed and braced, the first layer of earth backfill is brought in behind the wall and compacted.

[88] In the American Civil War (1861−1865) trenches were used for defensive positions throughout the struggle, but played an increasingly important role in the campaigns of the last two years.

[89] Military earthworks perhaps culminated in the vast network of trenches built during World War I (1914−1918) that stretched from Switzerland to the North Sea by the end of 1914.

The Germans were more willing to accept the trenches as long-term positions, and used concrete blocks to build secure shelters deep underground, often with electrical lighting and heating.

[95] The Syncrude Mildred Lake Tailings Dyke in Alberta, Canada, is an embankment dam about 18 kilometres (11 mi) long and from 40 to 88 metres (131 to 289 ft) high.

Best adobe shear strength came from horizontal reinforcement attached directly to vertical rebar spanning from footing to bond beam.