STRUCTURAL CHARACTERISTICS OF ASHLAR ROMAN WATCHTOWERS IN CILICIA REGION, ANATOLIA

Depending on requirements of the building type, ashlar masonry (that is a masonry technique composed of rectangular blocks); varies in terms of dimension of blocks, staggering ratio, wall profile, etc. Determination of impact of these variables on resistance is critical for the intervention decision process and sustainability of integrity and authenticity of dry masonry constructions. Therefore, the aim of the study is to determine characteristics effecting structural resistance and failure mechanisms of ashlar Cilician dry masonry watchtowers under lateral loading by quasi-static tilt analysis. Thus, the towers were documented in detail by traditional documentation techniques, the type of stone material were determined by Scanning Electron Microscope (SEM) equipped with X-Ray Energy Dispersive System (EDS) and X-ray Diffraction (XRD) analysis to identify friction coefficient and density values of stones to be used in simulation. Then virtual towers designed based on caharacteristics of case study towers were analysed by quasi-static tilting method. The towers present differences in terms of staggering ratio, which is the ratio between horizontal distance between joints (s) and height of the related course (h), and proportional relationship between heigth (H) and length (L) of the tower. Consequently, it is seen that staggering ratio affected out-plane resistance of the towers, increase in staggering ratio increased structural resistance. High staggering ratio (s/bh=1.4) provided total behavior. When the H/L ratio increased (H/L >= 2), the collapse angle of the towers decreased and slenderness of the towers increased, bending was observed. These results demonstrate that ancient masons were probably aware of structural precautions for resistance, they tried to use these techniques within the limits of the sources of the area.