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Earth block is a construction material made primarily from soil. Types of earth block include compressed earth block (CEB), compressed stabilized earth block (CSEB), and stabilized earth block (SEB). The term soil block is used interchangeably as in compressed soil block (CSB) or stabilized soil block (SSB). Compressed earth block (CEB) or pressed earth block is a building material made primarily from damp soil compressed at high pressure to form blocks. If the blocks are stabilized with a chemical binder such as Portland cement they are called compressed stabilized earth block (CSEB) or stabilized earth block (SEB). Creating CEBs differs from rammed earth in that the latter uses a larger formwork into which earth is poured and manually tamped down, creating larger forms such as a whole wall or more at one time rather than building blocks and adobe which is not compressed. Compressed earth block uses a mechanical press to form block out of an appropriate mix of fairly dry inorganic subsoil, non-expansive clay, aggregate, and sometimes a small amount of cement. Typically, around 3000 psi is applied in compression, and the original soil volume is reduced by about half. The compression strength of properly made CEB can meet or exceed that of typical cement or adobe brick. Building standards have been developed for CEB. CEB blocks are assembled onto walls using standard bricklaying and masonry techniques. The mortar may be a simple slurry made of the same soil/clay mix without aggregate, spread or brushed very thinly between the blocks for bonding, or cement mortar may also be used for high strength, or when construction during freeze-thaw cycles causes stability issues. Hydraform blocks are shaped to be interlocking. ==Development== CEB technology has been developed for low-cost construction, as an alternative to adobe, and with some advantages. A commercial industry has been advanced by eco-friendly contractors, manufacturers of the mechanical presses, and by cultural acceptance of the method. In the United States, most general contractors building with CEB are in the Southwestern states: New Mexico, Colorado, Arizona, California, and to a lesser extent in Texas. The methods and presses have been used for many years in Mexico, and in developing countries. The South African Department of Water Affairs and Forestry considers that CEB, locally called "Dutch brick" is an appropriate technology for a developing country, as are adobe, rammed earth and cob. All use natural building materials. In 2002 the International Institute for Energy Conservation was one of the winners of a World Bank Development Marketplace Award for a project to make an energy-efficient Dutch brick-making machine for home construction in South Africa. By making cheaper bricks that use earth, the project would reduce housing costs while stimulating the building industry. The machine would be mobile, allowing bricks to be made locally from earth. Various types of CEB production machines exist, from manual to semi-automated and fully automated, with increasing capital-investment and production rates, and decreased labor. Automated machines are more common in the developed world, and manual machines in the developing world. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Earth block」の詳細全文を読む スポンサード リンク
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