Abstract

Land becomes scared with city growth and it often becomes necessary to construct the building and other structure on the site in an unfavorable condition. Kirkuk city is currently experiencing significant urban growth due to its strategic location and its natural resources. Thus, the study of soil properties is very important. However, obtaining high-resolution soil maps by field survey is time-consuming and expensive. The objective of this study is to produce spatial distribution maps of soil properties which are bearing capacity, gypsum percentage and Calcium Carbonate (CaCO3) using geostatistical interpolation. Inverse Distance Weighting (IDW) and Radial Basis Functions (RBF) interpolation methods were applied for 51 boreholes to produce geotechnical properties maps of soil at depth of 1.5 meters. Furthermore, the two methods have been compared by applying root mean square error prediction (RMSE) accuracy assessment. The RMSE was (0.0136, 0.4538 and 0.4694) for bearing capacity, gypsum and CaCO3 respectively when the RBF have used. In contrast, RMSE was (0.4250, 0.1571 and 0.6834) for bearing capacity, gypsum and CaCO3 respectively when IDW have used. The result shows that the RBF method more accurate than IDW for producing bearing capacity and CaCO3 maps. While, IDW method more accurate for producing gypsum percentage in the soil. Finally, Fuzzy logic algorithm overlay has used to produce soil suitability map for building construction in the study area according to bearing capacity, gypsum and CaCO3. The result that obtained in this study can be used as elementary data to contribute soil hazard management and land use planning in Kirkuk city. The information resultant from this study has a significant impact on evaluating the feasible deformation on intended construction applications in the study area.