Rebuilding after an earthquake
Practical Action
Technology interventions areas
There were four broad technology intervention areas in the affected districts:
reconstruction of new buildings on new sites;
reconstruction of new buildings on old sites (including the recycling of the material);
strengthening of lightly and moderately damaged buildings in lower intensity zones; and
retrofitting of undamaged buildings in the region under risk. The main technology
intervention in the reconstruction areas was the seismic strengthening of walls and the
use of good-quality engineered and non-engineered masonry.
The primary seismic strengthening options were:
RCC tie beams at lintel and roof level;
RCC nominal plinth tie beams. Since the new buildings were only single-storey
structures that would be used for residential purposes, vertical reinforcements were
provided in the comers of the buildings.
The major walling options that were considered were:
improved coarse random rubble stone masonry in combination mortar (1:2:9
cement:lime:sand) with 45cm wall thickness;
graded stone concrete block masonry in combination mortar (1:2:9); and
hollow concrete block masonry in cement mortar (1:6):
In addition, the possibility of improving local stone masonry (with wall thickness of 35 to 45cm)
by the use of mud mortar with suitable strengthening was investigated. The strengthening would
be provided using lintel beams, RCC roofs, and RCC plinth beams.
The use of brick masonry was ruled out because of the totally inadequate quality of local bricks,
which have a crushing strength that is below the accepted engineering standard of 35kg/cm2.
Three foundations options were considered, including:
strip footings for murram soil sites;
strip footings for rocky sites; and
under-reamed RCC piles with a plinth beam for black cotton soils.
Conclusion
The earthquake in Maharashtra not only had a disastrous effect on the lives of its victims, but
was also a catalyst for change in the social fabric of the society. Relocation as part of
resettlement (in some cases up to 10km away) distanced the displaced victims from their vital
farming lands, and also led to other inevitable adjustments, such as the creation of a new
cultural environment, and, in relation to construction, a shift from a rural to a more urban type of
housing.
In the aftermath of an earthquake, providing housing is only one essential part of a disaster
recovery response. There are also issues of the mental and physical trauma of the victims to be
addressed, and rehabilitating the earthquake-affected communities not only materially but also
socially and economically.
Civil engineers must join forces with other agents involved in disaster response; consultants,
social workers, governmental and non-governmental organizations, and community-based groups
in order to ensure that a rehabilitation programme is appropriate and effective. An effective
disaster response engineer will be only one part of a wider process of managing the disaster
situation, and must co-ordinate and communicate with many of the agencies and individuals
involved.
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