Kath-Kuni architecture: field investigations and material characterisation

Abstract

An extensive investigation was carried out to gain better understanding of the seismic-resilient features of Kath-Kuni structures (mainly timber-laced dry masonry construction) prevalent in the Himachal Pradesh region of India. The research involved field reconnaissance surveys through rapid visual screening to understand the structural configuration. Laboratory testing was then conducted to evaluate the mechanical properties, joint characteristics and interfacial resistance of timber and stones. The results from the field survey indicted that the symmetrical geometry, the use of lintels above openings and corner interlocking were the major contributors to the seismic resilience of the buildings. Laboratory tests on the timber joints present in the walls – namely dowel connections and double-dovetail joints – revealed the importance of connection conditions in increasing the shearing capacity. The shearing capacity was also found to be dependent on the overburden pressure, with the smallest capacity of the connections in the top portion of the wall and the highest capacity at the bottom portion of the wall. The interface of timber and stones contributed to a further increase in the shearing capacity of the walls. This research provides the first insights into the mechanical behaviour of joints of Kath-Kuni structures.