RECONSTRUCTION AFTER EARTHQUAKE
Diagnosis and design
Team with Lucie Biarnes and Helen Le Berre
Architecture & Development NGO, ENSA-PB
SUSTAINABLE and EARTHQUAKE-PROOF RECONSTRUCTION
in Dolakha Region
Nepal, on the edge of India and China, is the third poorest country in Asia. In April and May 2015, the earth shook several times, weakening many homes and erasing a part of Nepalese heritage. A year and a half after these events and emergency actions by international NGOs, we went to Dolakha region, 20 minutes far from Kathmandu by helicopter, or 13 hours by coach because of the weakness of the infrastructures.
The country is also suffering from heavy floods during the monsoon from June to September, as well as frequent landslides. The life expectancy rate of Nepalese does not reach 68 years. Access to care in high altitudes and pollution are an integral part of national problems.
The international NGO Architecture&Development has proposed to us to carry out a technical and social in situ diagnosis in order to participate in the realization of a technical charter requested by the National Reconstruction Authority (NRA) created in January 2016 by the Government of Nepal. Indeed the government decided to provide installment to each family affected by the earthquake for the construction of a new house. The communist party wants to distribute financial aid fairly in three stages of construction: foundations, walls at the height of the sill and roof. At the end of these phases, mandated engineers validate the conformity of the production thanks to the technical guideline published by the NRA.
On-site, that theory is hardly visible. Too many households need financial resources and workers often misinterpret the new regulations. Cooperatives and associations are created by the inhabitants to ensure their survival and use to work with international NGOs.
For a week, we conducted a multitude of interviews with the inhabitants of two villages in the region of Dolakha and recorded 35 houses – destroyed traditional houses and CGI shelters equipments and infrastructures. We have also listed the water and electricity networks Geographic Information System.
The challenge of our work has been to propose a convincing methodology to maximize the reusable structure and materials of a private school with a stone basement and RCC post and beams on the second floor which suffered a lot the earthquakes.
In every hamlet, open-covered structures called “pati” traditionally enables social community activities.
They are used to gather people in rural areas. They should be reinforced to provide security to the citizens. They will become refuge areas in case of natural disaster.
Maina Pokhari private school has been seen as an illustration of these refuge areas.
In case of earthquake or flood crisis, the signal alert is emitted from the refuge area.
The bigger part of the existing structure has been kept, as far as the structural strength was ensured. Indeed, the most you modify an existing structure, the most it could be weakened.
The existing RCC slab of the second floor is half the weight of the stone walls. It is able to support the RCC columns and a new floor and framework.
However, the internal stone walls are in very bad shape, one of them is totally collapsed.
The South-West angle on the groundfloor has too many cracks and needs to be completely replaced.
The structure of the RCC staircase doesn’t stand on proper foundations and its location is not the best one to ensure evacuation in case of fire.
The building is disconnected from the embankment because in order to have two different resonance frequencies in case of earthquake. The flow around the building would also be smoother.
Here is the statement of the building after having removed all the defective materials. We may notice that the structure is not totally regular but still displays a generous open space.