KVPT’s Patan Darbar Earthquake Response Campaign - Work to Date - September 2016

Patukva Agam
Structural improvements include
a timber backup frame within the
structure and a two-layered system
of perpendicular diagonal planking
to increase stiffness and shear
capacity.
Photographs and sketch by Rohit Ranjitkar,
1996.
Timber reinforcement schemes in the 90’s:
Patukva Agam backup frame, Yetkha, Vambaha
The restoration of the Patukva Agam (restored 1994-8)
presented a significant structural challenge as its massive
rooftop and multi-tiered temple structure rested on a
dilapidated three-story base structure which was about
to collapse due to water damage. The Trust consulted
with the UK’s pre-eminent conservationist, Sir Bernard
Feilden, during his working visit with KVPT in 1994 regarding
the Agam as well as strengthening techniques for
the Ayuguthi. Eduard Sekler negotiated a consultancy
from Guy Nordenson to pursue the engineering concept
of a backup frame using massive timber members, an
idea which had been initiated in consultation with Sir
Bernard Feilden. Nordenson, a senior engineer at the
international engineering firm of Ove Arup, advised on
this innovative design. The solution can be described
as a framework of interior scaffolding, - massive timber
members carefully fit into the corners of the structure
and spanning floor joists designed to "catch " the
towering masonry and timber tower in case of failure. A
structural membrane created by multiple layers of timber
planking with staggered joints in 45 degree was introduced
at the floor level to provide horizontal rigidity,
replacing the historical thick mud floors. This backup
structural frame allowed us to leave the slightly tilting
facade masonry intact, without dismantling, so that the
extraordinary patina and irregularity of the facade could
be “frozen”.
Timber was chosen over steel both for its aesthetic flavor,
congruent with the medieval tiny crooked structure,
and because it would be easier to fit and install in the
tiny spaces, which allowed no extra room for machinery.
Steel and a timber backup frame were employed for
Patukva Agam, a dilapidated shrine building, in 1994-
97. In 1995 KVPT worked with Walther Mann and
the GTZ funded Patan Conservation and Development
Programme to develop the Vambaha timber ring beam
inserted at the roof plate and wall plate levels.
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