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At this time India is witnessing a new phase in development. with rapid economic growth
and high rate of urbanisation. Construction provides the direct means for the
development, expansion, improvement and maintenance of human settlements is
particular and economic growth in general. Construction activity accounts for more than
50% of the development outlays in India. Building construction costs are increasing at
rates which are So per cent over inflation. This is primarily due to the increase in the cost
of basic building materials like burnt brick, steel, cement, timber, etc. As a result, the cost
of construction using conventional building materials and construction forms range from
As. 40001- to As. 6000/- per sqm even for normal housing. Construction costs of this
order is beyond the affordable capacity of the economically Weaker Section and Low
Income Group and a large cross section of the Middle Income Groups, whose income
levels have not increased commensurately. This has become all the more relevant in the
macro context. due to the large volume of housing to be done in both rural and urban
areas and the limited resource of building materials and finance available. According to
the projections for the Ninth Five Year Plan, there will be a shortage of 6.6 million
houses in urban areas and 12.76 million houses in the rural areas at the end of year 2001,
inspite of all the Governmental efforts and resources.
However, it also needs to be recognized that construction also adversely affect the environment, through
physical disruption. the depletion of key renewable resources like fertile top soil, forest cover and excessive
consumption of energy. Therefore, there Is a strong need to adopt cost-effective, environmentally
appropriate technologies by upgradation of the traditional technologies and also using local materials as well
as using appropriate and intermediate technologies using modem construction materials with efficient,
effective technology inputs. Building materials is an area where enormous amount of innovation for cost
reduction, can be achieved. May bricks being the most important area for innovation as the total demand of
clay bricks, as an challenged walling material in India, is estimated at 180 billion per annum causing the
depletion 540.000 metric tonnes of fertile soil.
In the above background, Flyash, basically a waste material, has a dear edge over the
other construction material as it can be converted to a resource with minimum amount of
investments. Further, it can help to increase the speed and quality of construction and
thereby helping in enhancing the efficiency of housing delivery mechanism.
AVAILABILITY OF FLYASH
Total flyash generation in India from Thermal Power Plants is estimated at aboot 60 million tonnes per year,
which may increase to about 110 million tonnes per year by 2010 AD. India utilise only 3-4% of the flyash
generated as compared to more than 40% utilisation in Europe, China and America etc. The Government
has indicated a clear willingness to achieve 50% fIyash utilisation by the turn of the century at its enlarged
level of 90 million tonnes per annum. A variety of experiences are now available to us on the scenario at
different levels of manufacturing of flyash bricks.
Tiny Scale
The production of Fal-G based building material industries indicate a considerable
promise. These units are coming up at tiny and small scale sector along the coastal
PENDING
of HUDCO and West Bengal Power Development Corporation Limited (PDCL). The
Building Centre is responed manufacturing 25 lacs bricks per year (6 months working
period) using conventional technology since January 1991 where 50% ash is mixed with
clay. A significant proportion of bricks thus manufactured have been consumed by
Bharat Heavy Electrical LId. West Bengal Infrastructure Development Corporation LId..
Bharat Petroleum Corporation LId. Public Works Deptt. Govt. of West Bengal. Kolaghat
Thermal Power Station, Minapore Zilla Parishad and Panchayats alongwith large number
of families from low and middle income group of housing. The technology so far
practiced has been demonstrated before a good number of private brick manufacturing
units and so far forty private brick manufacturing units have applied this process
successfully.
Medium Scale
Various efforts have been made in different pans of the country to utilise the flyash in
medium level industries. However, these efforts appear to be quite exclusive and are
quite capital intensive.
Practically entire focus is on use of flyash with sand and lime etc. The production cost of
these flyash sand lime bricks etc. works out higher as compared to conventional walling
material available in the market. The most automatic and large scale production unit of
M/s Pulver Ash Ltd. is also giving adverse messages as the unit is said to be working at a
capacity of only upto 25% due to marketing problems. Another such example is of
Autocalaved Aerated Concete plant set up by M/s Ballarpur Industries Ltd. at Palwal
(Haryana) near Delhi, which is also not fully successful in generating enough market.
OTHER USES OF FLYASH FOR WALLING MATERIALS
Flyash can also be used for making a variety of building products, some using simple low
cost processes and others involving high investment processes high quality walling
material. The present state of art in manufacture of flyash products is outlined below.
1. Stabilized Mud Fly Ash Bricks
Compacted mud fly ash blocks stabilised with lime, cement or other chemicals can be
easily made. The problem of getting dry fly ash at the site, makes adoption of this
technology somewhat difficult.
2. Cellular Light Weight Concrete
CONCLUSION
There is an imperative need to produce more building materials for various elements of
construction and the role of alternative and innovative options would come into sharp
focus, considering the short supply, increasing cost and energy and environment
considerations for traditional and conventional materials. The possibility of using
innovative building materials and technologies, more so covering waste material like
Ifyash have been considered as a felt need.
Series of institutional support for land, for land, finance, regulatory, media, marketing
support, testing support and awareness creation would be needed and some of the existing
initiatives would have to be substantially strengthened, more importantly,
entrepreneurship for the production of appropriate flyash based walling, roofing and
flooring materials including Portland Pozzolana Cement and other cements to ad1ieve
better strength, energy saving, conservation of natural resources besides cost efficiency,
would have to be increasingly supported and developed.