Evaluation of The Materials of A Historical Building in Terms of Restoration: The Case of Ankara Kalecik Castle

Transferring the historical accumulation of a society to future generations is of great importance for the continuity and identity of that society. Kalecik Castle, built in 200 BC, has witnessed many civilizations since the Galatians period. The protection of historical buildings, which serve as a bridge from the past to the future, can be ensured by appropriate technique and material choices. In this study, the selection of appropriate materials and techniques in the restoration of historical buildings is discussed in the case of Ankara Kalecik Castle. Studies were carried out with samples taken from 4 facades of the castle (north, south, east, west). Physical tests and electron microscope analyzes (SEM and EDS) were performed on the samples taken from the castle. As a result of these analyzes, compressive strength, porosity, water absorption, density and unit volume weight values of the materials used in the structure were obtained. As a result of the EDS analysis, it was observed that the percentages of silicon-dominant elements on the north and south facades and calcium-dominant elements on the west and east facades were prominent. As a result of SEM analysis, it was determined that the particles exhibited a homogeneous distribution. In terms of compressive strength, the highest value was measured on the east facade and the lowest on the north facade. The results of other physical tests showed that the values of the four facades were close to each other. In the light of the data obtained from the samples, the castle was modeled with SAP 2000 program and the static condition of the structure was evaluated. As a result of numerical modeling and analysis, it was determined that the structure was stable under dead loads and it was predicted that the structure could be damaged under live loads.