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Dhajji Dewari is a non-engineered traditional construction mostly found in the northern areas of Pakistan and in Kashmir. The construction is based on timber framing with bracing members of different arrangements. The spaces between these timber bracings are filled with single wythe of stone or brick masonry laid in mud. Dhajji Dewari is a simple straight forward construction which can be easily constructed by using locally available materials i.e. wood and stones. This construction type is highly sustainable as the materials used are environment friendly, affordable, flexible in usage and durable which are the prime characteristics of a sustainable structural system (Abimaje & Baba, 2014). Around the world, timber frame buildings are now being designed to meet low energy construction standards as timber has a high standard of thermal comfort while consuming minimal non-renewable energy (Environmental benefits report). For over 200 years, this construction type is in practice. Similar construction types with little modification can also be found across the globe. Such buildings are mostly found in Britain (as half timbered), France (as colombage), Germany (as Fachwerk), Central America, South America, Turkey (as hımış), Greece, Portugal (as Gaiola) and Italy.
In event of an earthquake, such traditional timber buildings have performed very well around the globe. Various researches are available on these traditional buildings on their seismic or lateral load performance. Langenbach (2008) reported the remarkable performance of traditional timber construction in Turkey locally known as Hımış (Langenbach, 2008). In the 1999 Turkey earthquake, where a lot of modern reinforced concrete frame structures collapsed or were severely damaged, the traditional timber construction survived with light to moderate damage and very few were severely damaged or collapsed. In October 2005 earthquake in Pakistan, there was a massive collapse of modern reinforced concrete structures and unreinforced masonry structures, the traditional timber construction Dhajji Dewari performed exceptionally well. As there was no numerical evidence of the performance of Dhajji Dewari, the donors were reluctant in promoting and funding such construction.
Kasal et al. (2004) investigated the seismic performance of timber frames with fiber reinforced joints. A series of dynamic tests were conducted on a two-story frame to ascertain the seismic beahvior of frames (Kasal et al., 2004). Poposvki et al. (2002) investigated the role of connection material in timber frames and compared the steel bolts and glulam rivets fasteners for joints. It was concluded that glulam riveted connections were seismically more efficient as compared to bolted connections (Popovski, Prion, & Karacabeyli, 2002). Lam et al. (2002) reviewed the research work conducted on the timber structure’s performance during seismic activity (Lam, Filiatrault, Kawai, Nakajima, & Yamaguchi, 2002). Aktas and Turer (2016) conducted the full-scale testing of traditional Himis timber frames. Effect of change in geometrical configuration and infill was evaluated (Aktaş & Türer, 2016).
After a few years of earthquake initial research was started on this traditional construction. A full scale Dhajji Dewari wall was tested in the Earthquake centre of University of Peshawar Pakistan. Ali et al. (2010) studied the in-plane behaviour of full scale Dhajji Dewari walls under quasi static loading. This was the very first experimental approach to study the Dhajji Dewari behaviour under lateral loading which provided the very first drift limits, hysteretic response, vicious damping and strength envelop of Dhajji walls. It was concluded that the Dhajji Dewari system possess tremendous resilience against lateral loadings as it went through numerous load cycles before losing its structural integrity. Study further suggested that the performance of Dhajji Dewari is mainly controlled by the timber framework with no contribution from the infill (Ali, Schacher, Ashraf, Naeem, & Alam, 2010).