Rammed earth

The rammed-earth construction (or pisé ) is a massive building with earth - type, which is occupied since prehistoric times. In Roman times it was used in southern France, and later in Central France to the Middle Ages. In Portugal, parts of France and Great Britain it is still in use today. In the following years they got into Germany in oblivion, until the next receiving end of the 18th century in the form of " Lehmpisé - building " (French Piser, Spanish pisar = stomp ).

Processing

10-15 cm in height layers (not higher, otherwise no good compaction longer possible ) slightly moist clay with a bulk density 1700-2200 kg / m³ are poured between a pressure-tight formwork and compacted with tamping devices. Compared to traditional techniques reduces machine pitching the time and effort. After completion, you can immediately stripped, because there is no Abbind latency. Entering a just turned off the set but should be avoided initially. In the case of a non- freestanding rammed the ratio of height / depth may be (h / t) does not exceed the value of 12.

Pros and Cons

The frequently occurring in nature mixture of clay, sand and gravel is best for the rammed earth construction. This building material can thus be environmentally friendly because produced without high additional use of primary energy; In contrast to other building materials such as cement- concrete, burned or damped ( limestone ) - brick or steel. Moreover, clay is hygroscopic, ie (air ) Moisture absorbing and tampering, and thus acts as open-pored wood and other ( mostly ) natural building materials to promote health regulatory effect on the indoor climate. In addition, clay emits no allergenic or otherwise harmful synthetic substances. At a demolition or renovation of the building, this building material can be disposed of in the simplest way: either environmentally friendly and risk-free any place repositories, or re- enrich it with water up to the malleability and reuse. Also, the thermal insulation values ​​of clay are presentable and can, as is already common in earlier centuries, chop / by incorporation of straw or wood shavings still be significantly increased. A solid rammed earth reaches the F90 standard, but can be destroyed by the high pressure water jet of fire hoses at a fire fighting. By contrast, clay in the resistance to free water, hardness, pressure, train, Biegedruck-/Biegezugfestigkeit and elasticity components made of steel and / or cement- concrete inferior strong, which projects of construction with delicate yet supporting or cantilevered or high rising building parts very close sets limits. Where these features are much less or not required, is a clay with respect to the static reasonable, cost-effective building material.

Colors

Rammed earth is available in different shades, so should the case of components with stampflehmsichtigen surfaces such as concrete building in time are applied sample surfaces. Rammed earth has no binding colors, can also with the colors given by the natural clays, clays and aggregates, more or less occur strong deviations of the color. Desired dyeings can be achieved with earth pigments.