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

Opposite page
Manimandapa analysis-
Sample sheet from thought exercises
on pati typologies, recognizing
Manimandapa structures as unique
and weak in the greater context of
pati designs because of the massive
masonry walls bearing only on an
open timber column arcade.
Sketch by Evan Speer
On the other hand, the challenge will be to unify these
particularly top-heavy patis in spite of the openness of
their arcades (which leave no place to hide reinforcements)
without destroying them architecturally. Here
we meet our greatest preservation challenge in balancing
historical and technical, authenticity and seismic integrity.
The Manimandapas are coming to epitomize the post-
2015-earthquake seismic challenges, just as the Indrapur
Temple project of 1992 has for the Trust become emblematic
of our seismic work before the earthquake. At
the same time, because the two patis collapsed completely
down to their plinths in the 2015 earthquake, they
are among the rebuilding projects, where the international
consensus would support our conclusion that the
only responsible seismic solutions must include a unified
foundation-for which the use of concealed reinforced
concrete is the only known practical solution. It is because
this consensus has until now been consistently rejected
by the local authority, even since the earthquake,
that we say that foundations are the new battleground.
KVPT has over a dozen post-earthquake projects in the
works as of September 2016, with a handful of other
ongoing projects and a number of additional upcoming
projects identified. All of these include or will include
seismic strengthening design measures that are informed
by our past experience and our post-earthquake seismic
analysis. In the next section, we present the story of the
design work to date for the Manimandapas as a detailed
case study of the challenges, processes, and current seismic
design conclusions of our new project work since
April 25th of 2015.
Part IV
South Manimandapa - Seismic Design Case Study
For the purposes of the current report, we will take
the Manimandapa project - and specifically the South
Manimandapa - as an example of our ongoing projects.
Over the past few months, this project has proven to be
a unique challenge and has encompassed many of the
issues that have arisen on previous projects. We present
here a detailed discussion of the progression of this
project to date, in order to illustrate our seismic design
process and the issues that arise along the way.
The Manimandapa patis present a unique seismic dilemma
because of the imposition of a heavy brick masonry
perimeter wall bearing on an open arcade of timber columns,
-all with no direct vertical connections other than
weak traditional timber joints. During the earthquake,
these top-heavy structures shifted enough to roll the column
tenons out of their base connections and shear the
wooden tenons off the tops of columns, leaving the majority
of the timber columns intact. The design of this
structure is perhaps unique in the Kathmandu Valley.
Several other similar patis either have just a roof structure
bearing on a timber arcade, or have a masonry structure
above bearing on a partial timber arcade supplemented
by at least one brick masonry wall. The comparison of
different typologies of the pati structures, some surviving
and some collapsing, was among the multiple thought
exercises that have accompanied the design process for
the rebuild of the Mani Mandapas. This combination of
heavy upper structure with weak ground level structure,
lack of stiff connections throughout, and the mediocre
quality of the plinth construction below, resulted in a
perfect recipe for failure in a large earthquake.
The search for solutions for South Manimandapa drove
us to consider the range of options for how stiff a seismic
intervention should be in a given structure, and what the
implications of these options might be.
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