Rammed earth walls (aka pise) are constructed by the compacting (ramming) of moistened subsoil into place between temporary formwork panels. When dried, the result is a dense, hard monolithic wall.ed ed
A vernacular green building material as well as in more recent 'Eco houses', rammed earth is an ancient form of construction, usually associated with arid areas. There remain plentiful examples of the form around the world – evidence that rammed earth is a successful and durable way of building.
In recent years, rammed earth has become popular amongst environmentally-conscious
architects as well as those seeking an element of exoticism.
The likely future for the application of rammed earth is as:
- Thermal mass.
- Internal load-bearing unstabilised walls.
- External load-bearing stabilised walls.
Design
Rammed earth houses are custom designed to make the most energy-efficient use of the site.
They can be successfully designed for many climate regions, including humid areas with cold winters. The size and placement of windows is an important factor in taking advantage of solar heating in the winter and cooling breezes in the summer.
The house can be positioned to take advantage of hills that offer protection from storms. Shade trees or trellised vines offer relief from summer heat but admit warm sunlight in winter.
Many of the shortcomings associated with the durability of rammed earth (primarily
external surface protection, water resistance, shrinkage and strength) can be averted by the addition of a stabiliser.
Though other forms have been used, the most common stabilizer is cement, which when added typically makes up between 6 or 7% (by volume) of the mix.
The compressive strength of rammed earth is a maximum of 4.3 MPa (620 psi). This is less than that of concrete but more than sufficiently strong for domestic edifices.
One significant benefit of rammed earth is its high thermal mass: like brick or concrete, it can absorb heat during daytime and nocturnally release it
Коментарі