Barış Erdil

Seismic Resistance Evaluation of Traditional Ottoman Timber-Frame Hımış Houses: Frame Loadings and Material Tests

Traditional Ottoman timber-frame houses (“hımış”) form the major part of the cultural heritage structures in Turkey. There are many studies in the literature regarding the seismic performance of hımış houses, which claim that these structures have an inherent seismically resistant property. However, these studies lack a quantitative engineering approach and are based on observations made after contemporary earthquakes. This study presents the results of the seismic resistance evaluation of traditional Ottoman houses, made by means of reverse cyclic frame tests conducted on six yellow pine and two fir frames with and without infill (brick and adobe) or cladding (bağdadi and şamdolma). The experimental study, which was intended to differentiate the effects of infill materials, frame geometry, and timber type, has revealed that frames with bağdadi cladding and adobe infill resulted in the best and worst structural performances, respectively, while high ductility and good energy dissipation capacity characteristics were determined.

Testing and Seismic Capacity Evaluation of a Typical Traditional Ottoman Timber Frame

In Turkey, as well as in Balkan countries, examples of an extant housing tradition namely hımış, which was formed during Ottoman period, can still be observed. In spite of minor local differences according to geographical locations, these Ottoman hımış houses are distinguished with a number of common architectural and technical peculiarities that is worth to preserve. They have similar timber frame construction system with different infill materials. There are numerous reports claiming that the hımış houses are seismically more resistant than other construction types such as reinforced concrete and/or masonry structures. However, nearly all such reports are based on observations made after historical or contemporary earthquakes and lack quantitative engineering approach. For these reasons, within the framework of an ongoing research project, supported by The Scientific and Technological Research Council of Turkey (TUBITAK), coded 106M499, the seismic resistance of traditional timber frame houses in Turkey was investigated. A number of timber frames were tested in the laboratory under cyclic and reverse lateral loading, with and without infill. The results were reproduced with pertinent analytical work. As a result, it was shown that connections that were traditionally made with the sole use of standard nails were always the location of failure. In this paper, the results obtained for one of these frames is presented together with its capacity curve analysis to see whether strengthening is needed or not from seismic design point of view.

Confinement Effectiveness of CFRP in Axial Members under Various Loading Conditions

In this study, parameters affecting the mechanical properties of FRP-confined cylindrical and prismatic concrete columns were studied via experimental data, which were collected after an extensive literature review. The parameters were summarized as unconfined concrete strength, FRP thickness, cylinder diameter, overlap length of FRP, sustained stress level, heating-cooling effect and corner radius in prismatic specimens. Considering these parameters the confinement effectiveness is established analytically in the light of ultimate strength values obtained from the test results available in the literature. No steel reinforcement is taken into account because the main aim is to capture the behavior of FRP-confinement only. The analytical results revealed that unconfined concrete strength, FRP thickness, cross-sectional dimension of the specimen are the main parameters controlling the confinement effectiveness in cylindrical specimens. In addition to these parameters corner radius and sustained stress level are found to be significant in prismatic specimens.