Rebuilding after an earthquake
Practical Action
Local decisions
Once the initial surveys had taken place, the team set out to design a process that would ensure
that the communities were involved as much as possible in planning their new villages and
houses. The scale of building required about 80 villages for 200 000 people -meant that the
villagers were going to have to work together with professional builders. In many villages every
house had collapsed and rubble was strewn everywhere, and the need to provide shelter as soon
as the communities felt able to make decisions about abandoning villages and relocating, or
rebuilding on the site of such devastation and death meant that outside workers were going to
be involved as well.
The government set up and managed a rehabilitation centre, to which each community was
invited to send a representative. There the villagers discussed with the architects, planners, and
builders the options for rebuilding. Many villages had to be relocated, so they talked about and
decided where the new villages would be, how large they would be, and what type of school,
community centre, and health centre they wanted. They planned the layout of the new (or
rebuilt) villages, including infrastructure such as roads and water and electricity supply.
The most common failures in damaged buildings were the shattering and buckling of the outer
face of stone masonry walls because of the lack of through stones, and corner failure in stone
and brick masonry. Many walls had collapsed, including load-bearing walls, and there were also
many partial and total roof collapses. In RCC (reinforced cement concrete) structures the shear
failure of brick masonry was apparent where there was a vertical opening between brick joints.
Surprisingly, foundation settlement was uncommon in most of these houses.
A number of technical options for repairing non-engineered constructions and rebuilding were
examined, including seismic- resistant building technologies that have been developed and
promoted by various agencies. Traditional and improved traditional construction technologies
were also evaluated. The criteria for evaluating the technologies included:
Structural safety Technologies must meet the all structural requirements for seismic
zone 4 of the National Building Code.
Thermal comfort Houses must have adequate insulation and ventilation.
Maintainability Structures must be able to be maintained locally, and upgraded.
Cost effective The life cycle cost of the buildings should be as low as possible.
The cluster of technologies that emerged as the most appropriate for new construction in the
region were:
Walling Graded stone/concrete blocks and concrete hollow blocks: and
Roofing Shabad stone (a local material) on steel grilling, pre-cast RCC planking on pre-
cast joists, and RCC slabs cast in-situ.
Existing and traditional conditions
The affected area was connected by road to the Solapur-Hyderabad highway, which passes
through Omerga town in the Osmanabad district. Omerga is l70km from Hyderabad. In this
gently undulating hard rock terrain, with variable thicknesses of soil, the main feature that
influences damage from earthquakes is the depth of the bedrock and the type of soil overlying it.
Indirect factors like the presence of expansive clays and the possibility of liquefaction also need
to be considered. In swelling soils, unless sufficient care is taken to avoid differential
settlement, buildings are likely to develop cracks from the alternate wetting and drying of the
soil during different seasons, so increasing the risk of building collapse or damage due to
seismic shaking..
Damage was usually worse on sites with deep soils. In many villages situated on mounds over
deep soils the earthquake-related damage was extensive.
The existing building and construction technologies depended on raw material availability and
climate conditions. Stone, which was readily available, was the most common building material
in the area. The soil, mainly black cotton, was not good enough for earth or brick construction,
and hence local bricks were almost absent except for some bricks that were made from patches
of red soil, and white soil that was used for the roof insulation layer in most buildings. There
was very little timber available anymore, but a considerable quantity of timber was already used
in the houses and was recycled from generation to generation.
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