Please cite this article in press as: M. U˘ guryol, F. Kulako˘ glu, A preliminary study for the characterization of Kültepe’s adobe soils with the purpose of providing data for conservation and archaeology, Journal of Cultural Heritage (2013), http://dx.doi.org/10.1016/j.culher.2012.12.008 ARTICLE IN PRESS G Model CULHER-2704; No. of Pages 8 Journal of Cultural Heritage xxx (2013) xxx.e1–xxx.e8 Available online at www.sciencedirect.com A preliminary study for the characterization of Kültepe’s adobe soils with the purpose of providing data for conservation and archaeology Mehmet U˘ guryol a,∗ , Fikri Kulako˘ glu b a Yıldız Technical University, Vocational School of National Palaces and Historical Buildings, Architectural Restoration Program, 34349 Bes ¸ iktas ¸ , ˙ Istanbul, Turkey b Ankara University, Faculty of Languages and History-Geography, Department of Archaeology, 06100 Sıhhıye, Ankara, Turkey a r t i c l e i n f o Article history: Received 21 November 2012 Accepted 10 December 2012 Available online xxx Keywords: Soil characterization Adobe soil Mud-brick Adobe conservation Kültepe-Kanesh-Karum a b s t r a c t Kültepe (Kayseri) became an important trade and cultural center between Anatolia, Northern Syria and Mesopotamia starting with the end of the third millennium B.C. Kültepe structures, consisting of mud- brick walls on stone foundations and wood pillars to carry the roof, formed the basis of the typical Hittite architecture. The area excavated in Kültepe so far is only a part of this grand settlement; however, it is quite a large area compared to many other sites covered by protective constructions. So, it is very impor- tant to develop active conservation methods for Kültepe’s unsheltered adobe ruins that are under thread of erosion. In this study, a laboratory characterization was made for future experimental preservation studies, in which the physical, mineralogical and chemical properties of the in situ soil remains from a col- lapsed structure in Kültepe were measured. Initially, color classification, grain specific gravity and specific surface area were identified. Grain size distribution, consistency limits, volumetric and linear shrinkage ratios of the material were determined by mechanical analyses, and the soil was classified based on its granulometry and plasticity characteristics. Clay minerals were identified by X-ray diffraction (XRD) and scanning electron microscope (SEM-EDS) analyses, and sand grains were studied under binocular micro- scope and polarization microscope for mineralogical analyses. As for the chemicals analyses, soil pH was measured, soluble salt content was examined by simple spot tests and conductivity measurements, and organic matter, calcium carbonate contents were approximately determined according to weight loss on ignition. © 2013 Elsevier Masson SAS. All rights reserved. 1. Introduction and research aims Consolidants used for strengthening historical or archaeologi- cal adobe, or water repellent agents used to reduce adobe’s water absorption can be incompatible with the treated material. They can change the original appearance and properties of the material, accelerate its deterioration or even cause failure in a short time after the treatment. Using improper mortars or reproductions of adobe blocks, and substitution of adobe blocks with other building materials can have similar adverse effects on original structures. The soil used to prepare the repair mortars and mud-bricks should have, first of all, the grain size distribution similar to the original material in order to represent its physical characteristics. However, even when the grain size distribution is similar, different plasticity properties depending on the mineralogical composition of the clay can lead to varying swelling-shrinkage behavior and consistency states between the original and repair materials. Thereby, as well as determining the grain size distribution and plasticity properties, ∗ Corresponding author. E-mail address: uguryol@yahoo.com (M. U˘ guryol). identifying the clay mineralogy should be considered as another important process of adobe characterization. Gaining knowledge about the soil is also important in selecting the suitable conser- vation materials, as their performances can vary with respect to grain size distribution, grain mineralogy and constituents such as organic additives or natural organic ingredients. Investigation of soluble salts is another essential part of the characterization stud- ies in providing information regarding deterioration mechanisms, and in estimating the performances of the conservation materials in presence of salts. Considering these facts, the adobe soil from Kültepe was sub- jected to physical, mechanical, chemical and mineralogical analyses to investigate its composition and character. The study is a part of a research, which is aimed at: • reproducing mud-bricks, mud mortars/plasters that have sim- ilar properties to the originals which can be used for repairs, and be used for weathering tests after the application of tradi- tional, conventional, innovative conservation materials so that their potential performances on Kültepe’s adobe ruins can be better estimated and the outcomes evaluated; 1296-2074/$ – see front matter © 2013 Elsevier Masson SAS. All rights reserved. http://dx.doi.org/10.1016/j.culher.2012.12.008