In rural areas, usually of tropical developing countries, houses and shelters are mainly build of wood, bamboo and leaves and not very durable. When there is some money to spend, bricks are preferred as building material. Bricks are made in kilns, which requires wood for operation. Wood is becoming limited as these countries hardly have replanting projects, or “wood-growing industries”, that keeps this circle going.
Firewood is mostly taken from natural forest. In the past, these tropical countries had abundant natural forests. Unfortunately, their forest resources have significantly declined, due to civil wars, illegal logging or over cutting, population growth, etc.
Deforestation has economic and environmental consequences. It leads to firewood shortages, and adversely effects living conditions, especially of those in the rural area. Every day more forest and bushes are disappearing. The wood prices have increased significant over the past years and is becoming alarmingly expensive for the poor.
If rural people want to go for bricks, the road conditions are poor and transport doesn’t guarantee the fragile bricks to be delivered in one piece.A key feature of most of the UNDP conservation projects is encouragement of community engagement in forest protection and wildlife conservation. In this way, those that live in natural resource areas become part of the solution for their sustainability. UNDP projects also link these countries to actions under the Kyoto protocol to reduce emissions of harmful greenhouse gases, CO2 from combustion processes (wood), being one of the major ones.
THE SOLUTION
Bricks can be made without burning and the use of sun-dried bricks of soil is practiced since thousands of years, called adobe. In modern times, also rammed bricks are made, by compressing soil and then sun-dry them. These bricks however are not very strong, nor durable and tend to crack on drying, especially if so called "black cotton soil" is used.
It is therefore proposed to mix soil with sand and cement, while adding some water and then compress this material in a form giving mould, which results in strong and durable bricks, that do not crack. This can be done with simple and yet innovative manually operated brick presses, to produce interlocking soil bricks without burning from the freely available soil around (any kind of), allowing the rural population to build their own durable houses.
This fits well in environmental programs, that aim to reduce rural poverty and sustain economic growth, ensuring that future generations will be able to benefit from the rich environmental resources of the country, while reversing the loss of them.
Feasible, affordable and environmentally friendly, including significant cost savings and on-going environmental benefits, building with soil bricks is one of the most environmentally-sound building technologies in the world today, utilizing on-site available soils, as the main ingredient of the soil bricks.
The environment is protected in several ways:
- It lessens the environmental impact of building construction. The need for lumber is substantially reduced, thereby curtailing deforestation, drought, soil erosion, flooding, species displacement as well as the greenhouse effect
- It saves money. On-site manufacturing of brick eliminates a large portion of transportation, middlemen and breakage cost. This is because the soil bricks that might get broken for one reason or another, can be recycled through the manufacturing process. The structures made with soil bricks are as beautiful and durable as housing made from conventional bricks. The higher acoustical qualities of these houses shut out exterior noise for less stressful living. The interlocking blocks are more thermally radiant than conventional bricks and reduce the need to heat or cool the interior.
There is hence no need to burn the bricks, which makes this process a very low-energy requiring one. The soil is thought to originate for free from the building site itself and constitutes between 70 and 80% of the total mass of the bricks.
The press delivers bricks that are interlocking and thus don’t require jointing cement. This process uses 75% less cement than the conventional method. The bricks have cavities, that are filled by pouring thin cement, as to seal the bricks over their whole length and between the vertical joints, keeping small insects (ants) and rain water (drought) out. If required, steel or bamboo rods can be placed in the cavities as well, which would provide for earthquake resistant structures.
One of the main features of this brick type is, that it has more resilient strength than its fired counterparts. The secret of its success, is the composition of materials and the forming under moderate pressures. The soil brick is suitable especially for use in multi-storey buildings, due to its durability and robustness. It allows to abandon the inflexible and costly steel supported concrete column construction.
The bricks' cell interlocking system, eliminates the need for a horizontal mortar bed and anchoring reinforcements in wall corners and joints, thus reducing the demand for highly skilled brick layers, all together cutting the costs of construction considerably. Apart from the environmental benefits, the expected price of a pressed brick versus a conventional, burned brick, is at least 1:4 lower.
Brick presses allow rural people to create independently their own affordable bricks to build houses themselves and not have to rely on salesmen and production in towns, bad roads, transport problems and fluctuating prices. A brick press can be operated by the house builder himself or somebody can make a business of it, by serving other members of his community.
This simple, yet innovative technology can generate income when used as service to other villagers, which alleviates poverty and saves the forest at the same time. Most rural inhabitants are farmers who are often only busy for 6 months of the year and look for other employment during the remaining 6 months.
Though the idea of pressing bricks from soil is far from new and many have made an effort, for some unknown reasons this technology doesn't seem to have made its brake through. In my view it must have to do with wrong management, because the demand, or at least the need is there and the technology is simple (once you know how to do it).
Postingan
0 komentar:
Posting Komentar