Geostatistics of strength, modeling and GIS mapping of soil properties for residential purpose for Sulaimani City soils, Kurdistan Region, Iraq

The main objective of the present study is to measure the soil properties of the study area, Sulaimani City (35 degrees 33 ' 26 '' N 45 degrees 26 ' 08 '' E) and their spatial variability. A combination of conventional analytical methods and geostatistical methods were used to analyze the data for spatial variability. This study was focused on the correlations between the physical and mechanical properties and geostatistical analysis of the Sulaimani City soils based on the experimental data and the data collected from various research studies. The study was also focused on presenting the Atterberg limits, and the mechanical properties such as undrained shear strength of extruded soils using ArcGIS mapping. A total of 85 boreholes with depth up to 6 m underground were drilled and the physical and mechanical properties of the soils were tested. The index properties, compressibility properties, free swelling, and compressive strength of the soils were investigated and quantified with over 1000 data records collected from the literature. The field-tested data were compared with the data from literature and qualified using Vipulanandan correlation model. Using the mean, standard deviation, and coefficient of variation, the parameters of soils properties such as density (gamma), index properties, swelling index, initial void ratio, compression index (Cc) and undrained shear strength (S-u) properties were also studied. Undrained shear strength (S-u) of Sulaimani City soils varied from 10 to 119 kPa and quantified very well as a function of liquid limit, plasticity index, moisture content and dry density using the experimental data and data collected from the literature. Statistical analyses and ArcGIS zonation maps based on soil type are presented. Thus, these data are speedily available and can be valuable and provide suggestions for engineers and planners.