Correlation of Soil Liquefaction Potential Index and Geotechnical Properties for Baghdad City, Iraq

This paper comprises the study and analysis of Baghdad soil for eight geotechnical properties, which extract from field experiments of 630 boreholes with depth taken to 30m and representing 200 sites. Soil investigation reports are composed from altered laboratory tests. The soil layers. Divided into each 2m, which means 15 studied’ layers and soil properties values were embraced and submitted. in tables and charts which have been analysis-using excel2013 and check the charts using curve expert program to get the relationships between the properties values and the factor of safety against liquefaction. The correlations between liquefaction potential represented by the safety factor and soil properties for the available data of 200 sites in Baghdad have been studied and statistically studied ‘to evaluate both of soil properties and liquefaction potential index. Eight factors affecting liquefaction have been correlated with factor of safety for all earthquake magnitudes (ML= 4to 6.5 with 0.5 interval). These factors are, groundwater table, fill layer depth, standard penetration test (SPT- N value), saturated unit’ weight (γ), Relative density (Dr %), soil fractions (clay, silt and sand %), and total settlement (Stot). For better correlations, the same factors have been correlated with safety factor but for each earthquake magnitude alone.