Seismic Performance Assessment of Traditional Timber Himis Frames By Laboratory Testing and Capacity Spectrum Method

The observations made by various researchers after many historic and contemporary earthquakes suggest that traditional timber-frame himis houses, which still comprise a significant portion of the existing building stock in Turkey and in the Balkans, survived with insignificant damage in comparison to other construction types, hence they are seismically more resistant. However, these observations are based on qualitative evaluation and mostly lack a robust engineering approach. For this aim, a research project (no 106M499) funded by The Scientific and Technological Research Council of Turkey (TUBITAK) was carried out in order to assess and quantify the seismic performance of these buildings in relation to infill/cladding technique and frame geometry by means of full-scale frame tests and capacity/demand calculations. The results showed that himis frames will survive a design earthquake with any infill/cladding, although some are more advantageous than the others. In addition, the “window length” to “total length minus window length” ratio (WTLR) was shown to be a good indicator for rapid geometric evaluation. INTRODUCTION The general form and design principles of timber-frame himis houses were first developed in Western Aegean Region (Kuban, 1995) and applied to a vast area, from the Southern Middle Anatolia to Black Sea Coasts of Romania, Crimea, Bulgaria, Macedonia, Bosnia Herzegovina, Mora, to Croatia and Hungary in the north, regardless of drastic differences in climate (Kuban, 1995; Eldem I, 1984) (Figure 1). Himis houses have a hybrid construction system, where the ground floor is made of masonry with or without timber reinforcement, while the upper stories are comprised of timber frames. 1 Research Associate, Middle East Technical University, yasemindidem@yahoo.com 2 Assoc. Prof. Dr., Middle East Technical University, Ankara, aturer@metu.edu.tr 3 Prof. Dr., Middle East Technical University, Ankara, han@metu.edu.tr