Metro Plus
Bangalore
Chennai
Coimbatore
Delhi
Hyderabad
Kochi
A home for keeps
|
A very good and cheap alternative in low-cost housing is mud blocks
|
In the wake of natural disasters like tsunami and earthquakes, there is low-cost technology to help rehabilitate the homeless. — Photo: C. Rateesh Kumar
SHELTER: CRISIS or no crisis, is basic. Particularly, for those who can't afford it. Natural causes do not discriminate in disrupting a social fabric. This was evident when the tsunami devastated entire communities.
M.R. Yogananda, a doctorate in Civil Engineering from the Indian Institute of Science (IISc), his associates at Astra and Mrinmayee, a consultancy he has set up on alternative housing technology, are just the right people for the circumstance. Dr. Yogananda and his colleagues have evolved housing technology that is safe, eco-friendly, affordable, one that can be grasped and deployed by people themselves. Dr. Yogananda's associates from his consultancy are currently assessing housing needs in Nagapattinam, Cuddalore, and Velankanni. Based on their report, he and his associates will help in rehabilitation.
New techniques
Stabilised mud block technology entails the use of mud blocks, a mix of cement, lime, sand, quarry dust, and fly ash. Two techniques are employed: machine press and rammed earth. Under machine press, the Mardini press operated manually, presses the mix, which is then compacted and cured for 21 days. The block is ready for use. The machine can make any number of blocks, and on site.
The rammed earth technique produces a mud block without the use of a machine and is particularly helpful to those who can't afford the machine. Lime, quarry dust, sand, fly-ash and cement are poured into a mould, a rectangular steel box held together by nuts and bolts, and rammed manually using steel rammers. The rammers used are flat and blunt. The blunt helps compact the mix and once compacted, the block is ready. This block is done onsite and the mould can be fastened and unfastened anywhere. Dr. Yogananda's emphasis on rammed earth these days arises out of these advantages.
The quantity/texture of mix is based on the kind of house/structure required. "The blocks perform the requirements of any other wall. They are load-bearing walls and do not need columns/beams. Plastering is eliminated all together as the blocks are bound by mortar," says Dr. Yogananda.
Why stabilised? Because of the mix of cement and lime. Mud on its own disintegrates, he points out.
Astra worked on machine press technology for 10 years into the late '80s. No one believed such buildings would be stable. In 1987, Dr. Yogananda built his house entirely in mud block. "People asked questions about the house. No one will invest in something they doubt. Someone had to demonstrate that technology works, and since it was going to be my house anyway, I invested in it. Gradually the word spread," says Dr. Yogananda.
But it was the Latur quake in 2001 that got mud block technology off the blocks. The quake struck even as Dr. Yogananda and his associates were conducting a workshop on mud-block houses. "It was a coincidence. The devastation was there to see." They studied the conditions immediately and suggested structures that could handle quakes and would give people time to run out. "We built circular structures, bunkers, because they withstand quakes better. We inserted three-inch thick horizontal bands of concrete and steel within the masonry to bind them."
Dr. Yogananda received invites from Iran and Afghanistan to share knowledge on the technology following the successful demonstration in Kutch. Mrinmayee helped build a school in Afghanistan. Some of them are in those countries now outlining the concept of cost-effective housing.
The technology helps preserve energy. There is no burning of bricks, no use of coal, steel, timber. "This technology consumes only 30 per cent of the energy that goes into brick burning. You conserve 70 per cent energy," Dr. Yogananda points out.
Mrinmayee has built private houses, corporate buildings, Breaks India of the TVS group for instance, school buildings, hospitals, clinics in rural areas. One incident is particularly instructive of the benefits of this technology. "After the school fire tragedy in Kumbakonam, the Tamil Nadu Government passed an order stating that thatched roofing will no longer do. AC sheets were proposed. It can get really hot in Tamil Nadu and teachers were worried about work and students. We built vaulted roofs that allow for natural cooling and don't catch fire. If there is a quake, it gives time for students to run..."
Bangalore now has some 5,000 mud block houses. Kutch and parts of rural Orissa too have them. Dr. Yogananda says his objective is to train people in both technologies. "Once trained, they get to build their own houses. They don't need to pay for labour. And resources are locally available. They save a lot. The idea is to promote the technology. Not patent it."
PRASHANTH.G.N.
Printer friendly
page
Send this article to Friends by
E-Mail
Metro Plus
Bangalore
Chennai
Coimbatore
Delhi
Hyderabad
Kochi
|
