International experts point at need to invite foreign demolition contractors for high rise buildings
Kathmandu, May 29: While the government and general public are perplexed about pulling down the high-rises damaged by the tremors in the Kathmandu Valley, a team of international experts has suggested inviting demolition contractors from other parts of the world.
Speaking at an interaction programme here today, professors and engineers from the United States, Australia and New Zealand underscored the need to demolish the derelict high-rises as they posed threat to occupants in adjoining houses.
The engineers were presenting their opinions and suggestions after visiting Kathmandu, Sindhupalchowk and Bhaktapur and assessing about 800 houses and cultural monuments damaged by the earthquakes. The visit was coordinated by the Global Fairness Initiative Nepal and other organizations.
"Nepal urgently needs the support of demolition contractors. There are professional companies having expertise in such operations. Hence, I suggest Nepal government to invite those contractors," said Jason Ingham, professor of Civil, Environmental and Mine Engineering at the University of Auckland, New Zealand.
Ingham, who has expertise in structural engineering, however, suggested engaging such contractors with the local engineers.
"It is not happening only in Nepal. There is a lot of learning from other countries," said Ingham who has worked in the reconstruction and planning after the Canterbury earthquake in 2011 in New Zealand.
The government is seeking international assistance in demolishing the high-rises since it lacks the tools and equipment required to pull down the houses taller than four storeys.
Sonny Fite, Structural Engineering Manager at Target Corporation, USA suggested that the houses that sustained the jolts also needed to be evaluated since they might have been weakened internally.
"The damage assessment must be done by the structural engineers and they should communicate the finding to the house owner immediately," he said.
The experts also suggested not to demolish any building without detailed engineering.
The April 25 earthquake and powerful aftershocks completely damaged 500,000 buildings while more than 270,000 buildings were partially damaged.
According to the Ministry of Home Affairs, thousands of partially damaged houses in the Kathmandu valley needed to be demolished while the derelict buildings that pose threat to the people and houses nearby must be pulled down immediately.
Up to 30 storey buildings in the Valley
The engineers and experts said that 25 to 30 storey buildings can be constructed in the Kathmandu Valley.
However, they should be properly engineered, well conceived and reinforced, they said.
"The devastating earthquake and aftershocks have damaged the walls of the apartment buildings in the valley, their structure is fine. Therefore we suggest making a reinforced concrete wall at the centre of the building," said Art Schultz, an engineer from the US.
The engineers suggested not erecting buildings taller than two storeys if it doesn't use concrete structure.
"Don't vie for taller structure for non-engineered house, instead make short building and use bamboo and other light materials," opined Michael Griffiths, professor of Civil, Environment and Mining at the University of Adelaide, Australia.
The experts also said that the government's jurisdiction ability must be enhanced and there must be somebody to be held accountable.