Saturday, April 16, 2005

Bamboo Structure

Bamboo House, originally uploaded by Birdiez.

Giant Bamboo can make for some beautful buildings~


Anonymous Bamboo Central said...



BAMBOO offers an ecologically viable alternative to timber for construction. Bamboo is an extremely fast growing plant. Construction grade material is available in three years as opposed to ten to twenty years for timber. Unlike trees, harvesting does not kill the bamboo plant so an erosion problem is not created. Bamboo can grow in soil damaged by erosion, overgrazing or commercial agriculture and has been used for centuries for erosion control for that reason.. In tensile strength bamboo is the equivalent of a mild steel (15,000psi). Bamboo fibers are approximately ten times as strong as the wood fibers currently used in construction. Therefore, much smaller and lighter weight members of bamboo or engineered bamboo products can be used in place of timber and engineered timber products thereby reducing the amount of material being transported and used in construction.

Bamboo offers an opportunity for greater personal sovereignty. Individuals can literally grow their own home. An area the size of the building to be built can grow enough bamboo to build that building in five years, in the sixth year two buildings that size can be built from the same grove, in the seventh, three and so on.

Structural bamboo is now being treated with borates to create a long lasting insect and fungus resistant building material. In Costa Rica seventeen hundred homes a year are being built with bamboo under a government sponsored program using a borate treatment process. the wastes from the process are used to feed the bamboo plantations since boron is a necessary nutrient for plant growth. In Colombia, structural bamboo is being used to create large public buildings with arches spanning ninety feet. Our team has designed and constructed a number of smaller structures in bamboo in the Hawaiian islands. Obtaining a building permit has typically been a lengthy and tedious process since there is as yet no code standard to which the building officials can be referred.

The University of Hawaii is currently putting in an ICBO approved lab to test the primary species of bamboo used for construction so standards for the Uniform Building Code are not far off.

The Association for Bamboo in Construction

The Association of Bamboo for Construction is formed of individuals, companies and NGO’s whose primary concern is the responsible stewardship of the environment, second, the appropriate development and promotion of bamboo as a construction material, and to reduce pressure on timber and tropical forests.

The main purpose of the ABC is to uphold standards set by the ICBO and other responsible authorities i.e. ISO, ASTM, and provide certification of quality assurance to the bamboo flooring, furniture and panel standards will comply with ICBO building code standards for bamboo used in construction { for each species tested }. The Wood Sciences Institute, an accredited Center for testing Timber and Timber products, will do the testing.

The ABC will also develop Standards and Criteria for environmentally responsible agroforestry practices, i.e. propagation and harvesting practices and the treatment of bamboo by environmentally safe i.e."green" methods. Quality Assurance Certificates will be provided to the manufacturers, importers, government agencies and the general public on methods of preservative treatment such as the Boucherie or smoked process against insect attack, and adhesives being used for bamboo flooring and panel products. Quality assurance will naturally extend beyond housing into panel products, flooring and furniture industries as well, wherever treatment or environmental concerns are represented."

ARCHITECTS have been building with bamboo for centuries. The wealth of design and innovative techniques used in bamboo architecture is a world unto itself.
What is strong as steel, more sturdy than than concrete and grows to timber size in a year? The answer is Bamboo . Traditionally bamboo has been grown inefficiently and its real potential has been overlooked until recently. See the report on the bending strength by clicking Guadua.

Bamboo was used to build homes in many parts of Asia and continues to be used that way today. Posts, beams, rafters, flooring, walls and roofing were all made from bamboo poles and from weavings made from bamboo splits Click here to see a table on the Comparative Strengths of Bamboo

The five main species for building with bamboo are Dendrocalamus Asper, Atter, Strictus, Gigantalochia Apus and Guadua Agustifolia.

3:05 PM  
Anonymous Nat Geo said...

Tsunami Proofing: Where to Put Walls, Why to Keep Trees

John Roach
for National Geographic News

April 28, 2005

The images from the Indian Ocean tsunami that left nearly 300,000 dead or missing last December are striking. Amateur video shot in Phuket, Thailand, for example, shows huge ocean waves ripping across beachfront swimming pools and crashing through hotel lobbies.

"All of those videos were shot from the upper floors of hotels; [the buildings] survived," said Gerard Fryer, a geophysicist and tsunami expert at the University of Hawai'i at Manoa in Honolulu.

The hotels were among the few buildings left standing along coastal areas in South Asia and East Africa that were hit by the December 26 tsunami.

According to Fryer, the basic architecture of the buildings that survived serves as a take-home lesson from the catastrophe. All were built so that their load-bearing walls would escape a direct hit from incoming waves.

Bearing walls are key to the integrity of any structure. The walls support, in addition to their own weight, other parts of a buildings structure, such as upper floors and the roof. To survive the impact of a tsunami, bearing walls are built perpendicular (at right angles) to the shoreline.

"The building then does not offer much of an obstruction to the waves," Fryer said. "The waves break down the nonbearing walls, but the building is yielding and not collapsing. The building serves also as a wonderful sanctuary for anybody who wants to escape these things."

Forests, Mangroves, Reefs

Planting a forest between a building and the shore can also protect a building from a tsunami, Fryer said, because the trees serve as barriers that slow the water down.

The geophysicists said that, had natural mangrove forests been left intact in Banda Aceh, an Indonesian city that was devastated by the December 26 tsunami, many lives and buildings would have been spared.

According to the WWF, the conservation nonprofit, areas that had healthy coral reefs and intact mangrove forests were less severely impacted by the Indian Ocean tsunami than areas where the reefs had been damaged and the mangroves removed.

"Coral reefs act as a natural breakwater, and mangroves are a natural shock absorber, and this applies to floods and cyclones as well as tsunamis," Simon Cripps, director of WWF's endangered-seas program, said in a media statement.

The Gland, Switzerland-based conservation organization is urging that rebuilding efforts in the wake of the tsunami include rehabilitation and restoration of coral reefs, mangroves, and other natural buffers.

Fryer said, "The shoreline is a very attractive place, and we're prepared to put up with a lot to live there." However, he added, people need to acknowledge that hazards exist and adjust their building habits.

Tsunami "World Capital"

Fryer points to the Hawaiian Islands, describing them as "tsunami capital of the world." The islands earn the moniker because of their proximity to earthquake-prone trenches of the Pacific Ocean. The volcanic islands are also surrounded by undersea volcanoes that are prone to landslides, which can generate tsunamis.

The city of Hilo on the island of Hawaii, for example, was struck by a tsunami in 1946 and again in 1960. After the second set of destructive waves, city residents said enough is enough and moved Hilo inland.

The millions of tourists who flock to the Hawaiian Islands each year, however, have little intention of spending their holidays away from the beach—a reality that requires local officials to prepare escape plans.

Waikiki Beach on the island of Oahu is Hawaii's most popular destination. The beach itself is lined with towering hotels.

In 1986 a tsunami warning caused a full coastal evacuation in Hawaii, Fryer said. Waikiki was evacuated according to the existing escape plan, which quickly resulted in traffic gridlock—which would have been a disastrous situation had the tsunami warning been real.

In the event of a tsunami warning today, civil planners call for Waikiki visitors, residents, and workers to move to the upper floors of beachfront hotels.

"All the hotels in Waikiki were built half with the expectation there would be a big flooding event, so quite intentionally they have breakaway walls facing the ocean," Fryer said.

12:59 PM  

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