Underground structures in arid and semi-arid areas - understanding after visiting the mining town of Coober Pedy in Australia

When the author was researching underground buildings in the 20th century, he learned through literature that there were famous underground buildings in the Coobalpatti Opal Mining Town in Australia. In 2005, the author took advantage of the opportunity to visit relatives in Sydney, Australia, and specially selected the desert and big rock tourist route in central Australia, known as the "Dangerous Road". The highlight of this route was visiting the underground buildings of the Opal Mining City. Due to professional sensitivity, I obtained some information and photos in a very short period of time. Combined with my experience in studying underground buildings on loess, I make the following introduction for readers' reference.

Coober Pedy is located in the south-central part of Australia, belonging to the state of South Australia, 960km north of the state capital Adelaide. It has little precipitation, with an average annual precipitation of only 141mm, and a temperature of The temperature ranges from 0 to 47°C, sometimes reaching over 50°C. The land is a desert landscape, bare and unsuitable for farming. The deposit was discovered in 1915, which means that people arrived and lived there only at this time, and it only has a history of more than 90 years. The underground buildings here were formed with the development of the mining industry. When mining began, the miners felt that the underground space could not only withstand the harsh arid climate, but also save the huge cost of ground construction, so they used the abandoned mine caves as living spaces. Later, As the scale of mining expanded and the number of people increased, the needs for industrial and civil buildings also increased accordingly. Therefore, the mining stratum was used as a space for constructing underground buildings, thus forming a famous underground mining city with shops, restaurants, and lecture halls. , residences, churches, etc., you can see bits and pieces from some of the photos I took (photos 1 to 10). According to the tour guide, there are now 4,500 people in the mining city, and 80% of them live underground, which is not a small proportion. The underground buildings are built in the sedimentary layer. The lithology is sandy and semi-rocky, with a relatively uniform structure and few cracks. All I have seen are unlined underground spaces. The walls and roofs of the caves are coated with paint to prevent water from flooding. And rock and soil peeling, because the industrialization, modernization and urbanization of the mining city are the product of simultaneous development, there are complete modern facilities inside, such as water, electricity, gas and other supplies, and the production and living environment is comfortable. After viewing, I believe that the underground construction of the mining city is in a specific location or region. It is wise to understand nature, comply with nature, and thereby utilize nature. It avoids the unfavorable dry climate, utilizes favorable strata, and saves a lot of money. The energy and resources meet the requirements of sustainable development. The good experience of these underground buildings is worth learning.

The following is a discussion based on the situation of loess underground construction in my country. Our country's loess cave dwellings (underground buildings) are world-famous. In the 1980s, many world-famous architectural scholars came to my country to study ancient experience in this area. Our ancestors have been digging holes and living in the loess areas of the north since the cave-dwelling era. With the development of productivity, loess cave dwellings have been greatly developed during the farming period. Because farming has a farming radius, villages are scattered. Today, thousands of years later, there are loess cave dwellings everywhere on the Loess Plateau, still home to tens of millions of people. The reason is that it conforms to nature, takes advantage of the landforms, strata, lithology and other characteristics of loess, lives in cave dwellings that are warm in winter and cool in summer, and saves energy, materials and land. In the 1960s and 1970s, we learned from the needs of industry and the experience of loess cave dwellings as residential buildings. Through experimental research, we expanded the use space, and the results were very good. However, from the perspective of socio-economic development, many residential loess cave dwellings in our country are still in the agricultural era. Unlike the underground buildings in Aobao Mining City, which are the products of industrialization, modernization and urbanization at the same time, the production and living facilities in the caves are complete and the environment is comfortable. . However, my country's residential loess cave dwellings do not yet have the supply of water, electricity, gas, etc. that symbolizes modern production and living conditions. The decoration of the caves also contains few industrial products, which makes them seem a bit crude and inconvenient. Need to catch up with the development stage and modernize. With the acceleration of my country's modernization, this is not difficult to solve.

However, at present, some people who got rich first on the Loess Plateau only see the temporary simplicity and inconvenience of cave dwellings, coupled with the traditional concept of "cold caves", thinking that only poor people live in cave dwellings, and in addition, there are generally people who live in brick houses and small foreign houses. The trend of thinking that buildings are rich, fashionable and glorious makes these people often abandon cave dwellings and build ground-level buildings nearby, which wastes a lot of energy and resources and runs counter to sustainable development. It should attract the attention and correction of relevant parties. Once the truth is understood, it will be easy to manage. For material matters, we should use material methods, such as the decoration of caves and the supply of water, electricity, gas and other materials; for spiritual matters, we should use cultural, policy and other methods. Nowadays, scientific development is deeply rooted in the hearts of the people, energy conservation and emission reduction tasks are urgent, and people's livelihood projects are on the agenda. I believe that low-carbon, green loess underground buildings (cave dwellings) that can make full use of natural conditions will be well developed.

References

Book by Ji Golani (USA), translated by Xia Yun. Earth Covering Architecture (65). Beijing: China Industrial Press, July 1987

(This article was written on November 19, 2010)

Photo 1 Far-sighted underground building entrance

Photo 2 Near-sighted underground building entrance

Photo 3 Passage of underground store

Photo 4 Underground store

Photo 5 Front of underground lecture hall

Photo 6 Back of underground lecture hall

Photo 7 Underground passage and exhibition

Photo 8 Underground reception room

Photo 9 Underground bedroom

Photo 10 Underground study