LIQUEFACTION RISK ASSESSMENT IN THE 23 WARDS OF TOKYO USING ELASTOPLASTIC ANALYSIS
Keywords:Elastoplastic constitutive model, Soil-water coupled problem, Finite Element Method, Liquefaction
The risk assessment of liquefaction damage is crucial for recovery from large-scale earthquakes,which are predictedto occur in recent years. In this study, the liquefaction risk is evaluated over a wide area througheffective stress analysis, considering the interaction between the soil particles and pore water. The target area of the analysis was the 23 wards of Tokyo, including the zero-meter zone, and a 3D ground model was constructed from the borehole data. A vertical columnar ground model isestablishedat 463 locations from the 3D ground model using the material parameter determination flow. The liquefaction risk of a wide area isevaluated by performingseismic response analysis using two types of earthquake motions for each analysis point, thus showingthe difference in the risk and degree of liquefaction by location.In the future, various dynamicanalyses must be conducted with sufficient resolution and compared with the actualdamages.