Ar.
Shekhar Garud graduated from School of Planning and Architecture, New Delhi in 1984. He is partner in the firm
Narendra Dengle and Associates and currently teaches at VIT’s PVP College of
Architecture, Pune. He has been actively associated with IIA, AESA,BAI,PCERF.
Ferrocement is commonly known to be a
mixture of Portland cement and sand applied over layers of woven or expanded
steel mesh and closely spaced small diameter steel rebars. Being able to be
formed into relatively thin, curved sheets, it is extensively used to form
hulls for boats, shell roofs, water tanks, sculptures, prefabricated building
components etc.
A Frenchman, Joseph Monier ( 1823-1906)
invented “Ciement arme”. As a gardener, not satisfied with clay pots which are
easily broken, he experimented with embedding iron mesh in cement and sand
mixture and invented ferrocrete troughs and later on even took patents for
iron-reinforced cement pipes, cement panels for building facades and other
reinforced concrete products. Paris exposition of 1867, brought the attention
of the world on his products and patents and reinforced concrete started
becoming a prominent building material.
Another French inventor, Joseph-Louis
Lambot (1814-1887) was also simultaneously working laong the same lines who
first constructed a boat in reinforced cement concrete and exhibited at
Exposition Universelle at Paris in 1855.
In 1875, Monier expanded his patents to
include even bridges and designed his first steel and concrete bridge. He also
introduced “Faux Bois” concrete in which the outer layer was sculpted to mimic
rustic logs and timbers.
Ferrocrete, with relatively good strength,
resistance to impact , better resistance to fire, earthquake and corrosion than
traditional methods such as wood, adobe and stone masonary, has become quite a
popular material not only in construction but also creating “novelty
architecture”. It has become popular because the technique can be learned very
quickly, thus people are able to supply their own labour and become active
participants in the process.
Ferrocrete as a construction technique was
made popular in India by a gifted structural engineer and alumnus of College of
Engineering, Pune of 1948 batch, late shri Vishnu Joshi. While working with the
renowned architect Joseph Alan Stein as structural engineer and designing
structures for many landmark buildings like Express Towers at Mumbai, India
International Centre and India Habitat Centre at New Delhi, he explored
“Ferrocrete” as a material for innovative use. He believed “it was most
suitable for developing countries, which could help in employability of
unskilled labour.” It was his passion and commitment to the spread of knowledge
that inspired a generation of architects, structural engineers as well as civil
contractors to explore ferrocrete in innovative ways. Apart from creating miscellaneous building
components for use in building industry and irrigation projects, his vision
inspired many to create fascinating building forms using ferrocrete.
As he settled in Pune in later part of his
life, his vision and guidance inspired Ar. Narendra Dengle to design some
fascinating roof forms which explore the freedom offered by ferrocrete,
unmatched by ordinary reinforced cement concrete. While the architect
skillfully explored the forms, the expertise and experience of late shri V.D.
Joshi ensured the strength, stability and performance of the structure.
Architect’s own house and studio at Pune,
constructed during 1995-1997 provided the first opportunity to explore the
possibilities and the freedom offered by ferrocrete. For a house designed with
minimal use of RCC and extensive
use
of load bearing construction in hollow concrete blocks, modulated roof forms in
curved ferrocrete “in-situ” construction was the natural choice. With the use
of plywood shuttering, bent to desired shape, interesting volumes could be
created for the first floor rooms. Along with the “in-situ” ferrocrete roofing,
pre-cast panels/petals were used to construct a truncated dome (Shankav) over
the central double heighted family space. Even though, the volumes are large
and complex, the structure itself is very light and Elegant.
The Welfare Centre for workers at Deccan
Florabase, a floriculture project near Pune, executed during 1998-2001,
consisted of tow overlapping octagons in plan. The roof was designed as a
folded plate structure with a central skylight and covered by a thin ferrocrete
skin. The skin was cast in-situ supported by “Sitatex” boards used as lost
shuttering over a steel structure. China mosaic finish offered the
waterproofing and acted as a thermal reflector.
During the same period, a guest house
complex at Vansda, Gujrath was constructed for BAIF, Pune. Since BAIF had been
actively promoting use of ferrocrete for constructing Toilets in remote
villages by training the villagers, they readily accepted the pyramidal roof
over the Canteen and sloping roofs for the guest rooms, both to be done in
precast ferrocrete panels. The pyramidal roof with a skylight at top was
conceived as an assemblage of easily manageable pre-cast ferrocrete plates
which when could be joined together with cast-in-situ edge beams. Once the
structure was complete, batons were cast in cement mortar for placing the
manglore tiles over them. The guest rooms were also provided with pre-cast
ferrocrete panels complete with eaves boards, finished in manglore tile
roofing. This technique along with the exposed brick walls created a harmonious
architecture in the rural setting. The pre-casting techniques saved lot of
labour and it could be done under skilled supervision by unskilled workers. It
also demonstrated a new economical and better performing technique of building
sloping roofs compatible with the local architecture.
The “Universal Temple of Sri Ramakrishna”
at Pune, built during 1998-2002, provided a unique opportunity to explore
ferrocrete daringly for one of the most conspicuous elements of Indian temples,
i.e. the shikhara. The architect has deviated from the practice of making the shikhara
as a solid element with various types of adornment and created a lightweight,
porous and transparent shikhara. Thus not only the association of the devotees
with the traditional image of the temple is respected but an aesthetic
experiment in using ferrocrete technology hs been successfully carried out. The
petals of the dome were precast on the ground when the main structure was being
built and then they were joined together progressively with cas-in-situ ribs.
The petals of the smaller domes were also precast and then assembled on site. Glass mosaic
tiles have been applied over the exposed surfaces as a waterproofing and
aesthetically pleasing finish. While the traditional shikaras are always lit up
from outside, this unique shikhara “glows from within”. The precasting
technique saved major construction time and simplified the construction itself.
All the above experiments which involved
the imaginative architectural solutions supported by innate understanding of
the structural aspects were guided by late shri V.D.Joshi. After his demise,
the ferrocrete technology was nurtured by his disciples with equal passion. Ar.
Dengle designed further projects with
Er. Bhalchandra Bhedasgaonkar who had been trained by late V.D. Joshi in the
ferrocrete technology.
For the extension of Swami Samartha Math at
Hedavi, built during 2007-09) a different attempt was made in the form of a
asymmetrical pyramid over the existing garbhagirha. The roof is envisaged as a
skin of asymmetrical stepped pyramid supported on sloping RCC beams. The
stepped form was explored to create opening at various levels for admitting
light and ventilation in the spaces below.
The proposed Railway Museum at Mysore, has
been conceived as three interconnected vaults like a wavy tunnel under which
the vintage collection of railway engines and bogies will be displayed. Here
again the ferrocrete skin is wrapped over the steel structure of the vaults.
The skin has a layer of thermocole sandwitched in between the ferrocrete skins.
The structure would be light and the construction time for such a large volume
would be less.
At present, the redevelopment of the
Mhasoba Deosthan at village Kharawade near Pune is under construction which
also has a shikhara over garbhagirha with precast petals assembled on site with cast-in-situ ribs. The Sabhamandap will
have a pyramidal stepped roof with in-situ ferrocrete skin with sandwitched
thermorcole offering thermal insulation.
Ferrocrete does offer interesting
possibilities in modulating the roof forms provided the structural engineer
guides the architect in resolving the stability and strength issues. Adequate
care and expert supervision to ensure quality and maintaining accuracy of the
geometry is very critical. Ferrocrete is not only a material / technique to
produce low cost building components but can be explored most imaginatively by
architects and open minded structural engineers to create a different spatial
experience.
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