Dynamic properties of soils in the northern coast of Izmir Bay area

In this study, dynamic properties of soils in the northern coast of Izmir Bay area are investigated by dynamic site response analyses and microtremor measurements. Fundamental periods of soil profiles that are obtained from both methods are compared. Variation of dynamic soil properties in the northern coast of Izmir Bay are investigated depending on the bedrock depth and heterogeneous soil structure in the site. Dynamic site response analyses based on equivalent-linear methodology have been performed for 50 borehole locations. Liquefaction analyses are also performed at borehole locations, liquefaction potential index is calculated, and level of liquefaction risk is determined. While the liquefaction risk is very low or none for the moderate scale earthquake (M=5.3), medium-high levels of liquefaction risk for the scenario earthquake magnitude (M=6.5) is found. Fundamental periods obtained from microtremor measurements and those calculated from dynamic analyses are close to each other. Fundamental periods vary in the range of 0.65-1.2 s depending on the bedrock depth in the study area. Fundamental period is higher where the bedrock depth increases.