a) Independence and availability.
An important factor in favor of the mud is their independence and abundance, availability and use of raw materials for community participation and use by unskilled labor.
In the case of traditional adobe, another benefit is the ease of cutting, turning or adjusting dimensionally.
c) Cost of manufacture.
Traditional technologies discussed here in the mud (adobe, adobe, mud pressing) no energy requirements than the use of the sun as a source of drying. This represents a significant savings relative to other technologies.
In the case of the traditional adobe as construction material cost savings in energy production is decisive factor, especially when considering that the “burning” of the brick red clay represents 40% of the cost. If we compare the energy values required to produce both materials we find that 2,000 Btu to 30,000 against the adobe brick oven.
d) Soundproofing and air conditioning.
The use of mud in building a good acoustic and insulation, even when no pede be classified as a good thermal insulation in areas where there are marked differences in day-night temperature outside the wall of mud acts as a regulator in the environmental field domestic air conditioning.
e) environmental sense.
From the standpoint of growing environmental awareness that characterizes the current architecture is put together with mud environmentally sound technologies because of their auto recycling.
Buildings that incorporate the use of clay are particularly vulnerable to deterioration and deserving of care and maintenance. This of course depends greatly on the degree of stabilization and compaction of the material used and its original conditions. In walls of compressed earth establilizada and these weaknesses are minimal while the maximum rise buildings using traditional adobe adobe or not stabilized.
Another weakness is so far down the popularity it enjoys in the field of mechanization of industrial building systems due to its excessive dependence on manual labor ( “work intensive”), which tends to make the services of its professional production.
9 – CONSTRUCTION OF PRESERVATION OF ADOBE
“The preservation and rehabilitation of a deteriorated adobe building is the more successful the more closely approximates the use of techniques that were used in the original construction.”
“The cyclical maintenance is key to revitalizing the use of adobe as building material.”
“The preservation of the adobe is one of the most difficult problems of conservation. Under the impact of weather, rain and increased humidity, mud and dirt to be reverted and collapses back inexorably to the land. Traditionally, the houses Mud and residential buildings are subject to annual repairs and maintenance, often adding to the natural mud additives to make it more durable. ”
“In the late’80s, when the excavations at Tel Dan in Israel revealed a triple-arched gate mud brick from the middle of the Bronze Age, the GCI was interested in investigating the preservation of the adobe. In a short period of exposure to the elements, the site began to deteriorate rapidly. ”
The use of siloxanes and hydrophobic polisilicatos are a great resource in the recovery of historical architecture constructed with mud, but their high cost undermines the popularity of its use and disclosure.
Expertise in the restoration of archaeological works in mud or in the recovery of historic and artistic heritage of the countries engaged in their use is an important technological resource.
Deterioration of signs and sources of construction in adobe
– Damage caused by structural foundations insufficient, poor quality material or effects of external forces such as wind, water and earthquakes.
– Problems caused by excess moisture or humidity or rain water in the subsurface due to natural causes or inadequate drainage.
– Agrietamento caused by incompatibilities between the rat expansion / contraction in relation to the existing frieze on the wall of mud that coats.
More specifically referring to the humidity as the most aggressive and most common cause of deterioration of the adobe buildings can be made several recommendations:
1) Verify and restrict undesirable vegetation close to the construction of adobe, as the roots can penetrate the building leading to an excess of moisture inside of it.
2) Check the drainage of the pavement immediately to ensure the construction of adobe because it offers outstanding emposamiento appropriate to avoid the water at the foot of its walls.
3) Consider creating drainage channels which help to ease the burden of excessive water on the building.
4) Strengthen and wall friezes original hygroscopic applying protective films and / or waterproofing.
5) To combat wind erosion in the upper part of walls or in extreme cases into a curtain of vegetation as windbreaks.
6) To combat the ingress of pests, insects and rodents or birds that help accelerate the deterioration process of building.
7) To combat the growth of parasitic plants that stay in the interstices of the walls of the building.
10 – REASONS FOR THE DECREASE OF IMPORTANCE IN THE USE OF BARRO as construction materials.
There are a number of reasons for the loss of popularity of the technology of mud buildings in recent decades. Among them:
1) demands intensive labor.
2) Picture of the associated works mud in our latitudes (for misinformation) with “poverty.” Ironically, in other more technologically updated and effluent is currently considered a symbol of status.
3) regulatory ordinances construction.
4) cyclic maintenance requirements.
5) Image advertising. Constructions based on conventional technologies involving marketable an army of publicists: writers, builders, business owners of manufacturing materials, plumbing, blacksmithing, carpentry, and many more carriers. The builders of earthen structures show a very low-profile advertising.
But these conditions show signs of changing in the light of recent advances in the field of preservation of buildings and the continuing advances in technology and resource building.
10 – NEW TECHNOLOGIES AND ATTITUDES IN THE USE OF CLAY UNDER CONSTRUCTION
Presents a sample of experiences that they go in search of applications and innovations in the traditional mud.
A-Adobe. New interpretations of a traditional technology
Currently witnessed in the beginning of a change in habits and attitudes about what had traditionally been the culture of the mud in construction. Today, without neglecting the approaches of the use of mud applied to technology use popular, low cost, saw the construction technology and resources have opened up roads in the use of once-despised and humble adobe that stimulate creativity and sensitivity to the architectural forms of mud in the architect today. The technology seems to have entered the mud, as we said earlier, a new phase not only refreshed and review of its management and construction technology but also their ability to express in architectural form and their collective value as an element of prestige within the urban life in which he had begun to participate with renewed vigor.
Progress of mechanization
From an inventory study of technologies used in the production of 288 million adobe bricks in New Mexico, USA in 1994 found that only 1% is devoted to the use of traditional manual technology while 99% is divided shared equally between mechanical production methods and semi-mechanical. Moreover the volume of production of stabilized adobe bricks are very low and only while the application of the blocks of clay pressed type CINVA-RAM was also very low only equivalent to 118,000 blocks.
Comparative production figures
Traditional construction (manual) adobe: adobe 300-500 / day
Construction of semi-mechanized adobes: 1.500-3.000 adobes per day
Mechanized construction of adobe: adobe 3,000 + / day
Adobe “High Technology”
“While the right combination of mud and clay remains unchanged, in this type of mud is added a new component: emulsified asphalt. This emulsion is a byproduct of petroleum which is commonly used in road construction. When mixed with water, mud and clay, depending on the ratio, you get a brick of adobe waterproof (semi-stabilized) or completely waterproofed (fully stabilized). The addition of emulsified asphalt is not accepted by all, since the outer wall of mud will be covered with a plaster (plaster). When the wall is an interior garden courtyard or their use is justified. The “purists” are not comfortable with the idea of adding oil to a product which, in itself offers a natural beauty to the building. Any asphalt gasification is another cause for concern. All construction materials used in a release gases that are found to be harmful, and some of them carcinogenic. We are not aware of the issue has been investigated the gasification of bitumen emulsion in some detail, especially its possible effects in the long term. ”
Pumice with Adobe to build shelters in the mountains of Colorado
This technology, experienced by William Porter and his non-profit company “Sangre de Cristo Adobe Solar Works uses a mobile unit for transportation of construction materials pumice (” scum “) very light, reddish color, texture, full of coral hollows and ridges that promote adherence to the mud of low cost and non-expansive when wetted. Once on the site, you are mixed with clay in a ratio of five parts of slag pumice for a part of local clay and 4% by weight of asphalt emulsion which results in a block maneuverable and lightweight, providing While a good balance of the isolation mass.
Building with wood chips and clay lightweight filler
One of the latest innovations in the development of modern German technology building with mud is the use of wood chips amalgamated with clay and used as lightweight insulation in external walls and internal. Since its emergence in the construction market in the early nineties, the contractors have been able to offer a piece of clay filler, monolithic, natural and healthy. The slippage of material used is comparable to the systems of mud and straw, but much shorter production time, easier to construct and less time for drying and curing. Additionally, it is more efficient, and less emphasis on the involvement of human resource.
The mixing ratio is 3-4 buckets of chips for every bucket of mud light depending on the strength / weight required, the quality of the clay and the size of chips used. This combination is amalgamated into the mixer for one minute until all chips that have been coated with a layer of mud and, upon completion, is already ready to be cast in the formaletas forming the mold wall. Then empty the mixture processed to verify the absence of empty spaces.
It is feasible to use a variety of resources and sustaining the fabric of the mud wall, including the use of bamboo sticks. Other types of wood frames more or less formal as the case may be used. The existence of the plot contributes to sustaining rigid and fortify the constitution of the wall, at the same time reducing the chances of contraction. Once dry the surface of the wall can be implemented on a frieze of plaster it without difficulty.
A wall of 30 cm. thickness may require approximately eight weeks of drying time.
Industrialization of the B-Bahareque
“One man alone can not build your own house but ten men working in a group can easily build ten houses.”
– Hassan Fathi
Inspired by this philosophy, the French-Canadian “Polypus, based in Canada, projected to the world of systematized technology bahareque (provided that the system called” bajareque “) beginning with applications in Latin American and Arab countries. A source of surprises in this increasingly globalizing societies living on the planet …
The product of the experience of Polypus, to demonstrate the superior performance of traditional structures of reeds and mud, endure unscathed a devastating earthquake in Central America, is a type of housing construction “basket” flexible and adaptable to external conditions, formed for a structure that uses a sustaining frame of treated wood against insects and moisture, as a plot, on which lies a mass of lateritic clay. This simple structure can be transported in crates to the remotest regions to its conformation in place. So, a box of 1.20 x 1.20 x 3.60 mts. and about 320 kg. can accommodate the weight of components to build a house with an area of 40 m2.
Barro casting (cast earth “) and calcined gypsum
The technology does not require emptying mud placing bricks or adobe blocks or rammed earth walls typical slow compaction of the clay technology. In contrast, consists of a rapidly emptying construction once and for all can be used to remove formaletas short time emptying. What makes the above setting is the speed of calcined gypsum and the increase in strength until it reaches a strength, yet moist enough to support a wall in its final site. And most surprising of all is the very low concentration of material required to agglutinate the mud that comes with it. A ratio of 15% or less of calcined gypsum provide sufficient strength to perform the process described above. And do not warrant metal reinforcements …
Traditionally, the technology of building with mud reflects an image of intensive labor that makes it attractive only to very poor (who use it without intermediaries) or the very rich (who can pay for it). In contrast, the technology of clay casting, combined with a ratio of calcined gypsum reduces the work difficult and slow labor of replacing it once a few hours of use of construction machinery. And the innovative design does not lose its validity as the “armed” the material is in its plastic state.
The costs of construction with the technology of clay casting are significantly lower than those for adobe and rammed earth and even could be, depending on the circumstances, regarding the “new” bahareque (systematic).
Technology is competitive in mud casting a wide spectrum ranging from houses to the mass production of high costs to purchase.
Despite their natural resistance to moisture, it is always advisable to coat the outer surface of walls with a layer of silicone once the wall is built totlalmente dry. This spray without altering their appearance offers a protection which extends up to five years.