The topics of stress distribution around underground openings and stability of these openings are well-known in the field of Geomechanics. Accordingly, underground openings start to fail where stress concentration is the highest. The locations of failure and stability are related to the shape of the opening; among others. Our recent survey and the analysis of historical civil structures around the Lake Van, Turkey, indicate that the key in the long-term survivability (stability) of historical structures subjected to multiple earthquakes may also be related to the incorporation of certain shapes in their architecture. The purpose of this paper is to present examples from the surviving historical structures from the Lake Van area and discuss factors, specifically the shape factor, affecting their long-term survival. The landscape of Van area is rich in historical architecture as well as in occurrence of earthquakes; providing a unique laboratory to study and analyze the effects of earthquakes on historical civil structures. The knowledge gained, on factors affecting the survivability of historical structures under repeated earthquakes, should help in design of structures which can survive earthquakes with less damage than experienced by many of today's modern structures.
Earthquakes can cause sheer destruction on civil structures. However, there are many historical structures which, despite being located in earthquake zones and subjected to earthquakes over and over again, managed to survive thousands of years and are available today for examination and learning about their secrets of survival. The purpose of this paper is to present examples from the surviving historical structures from the Lake Van area, Turkey, and discuss factors, specifically the shape factor, affecting their long-term survival. The landscape of the Lake Van area is rich in historical architecture as well as in occurrence of earthquakes; providing a unique laboratory to study and analyze the effects of earthquakes on historical civil structures. The Lake Van is located at the eastern part of Turkey (Figure 1). The study area surrounds the Lake Van and is within two eastern provinces; namely Bitlis and Van. The Van province borders with Iran. Historically, the shores of the Lake Van and the surrounding region has been a region of convergence for Asian, European, Persian, and Arabic peoples for more than 2000 years; a region where eastern, western, northern and southern cultures come together. These cultures established important civilizations of their time. Urartians, Byzantines, Seljucks, Ottomans were the powers of the area at one time or another and all of them built various impressive structures. Some of these structures are available to examinations today and specifically those structures around the Lake of Van, constitute study materials for this study. The Lake Van area is also important seismically, as it is located on the north-end of the Karlıova joint where the Arabian and Eurasian and Caucasian plates intersect via two major active faults: North-Anatolian and East Anatolian faults (Figure 2, Reilinger et al., 2007).