The Over-Prediction of Seismically Induced Soil Liquefaction during the 2016 Kumamoto, Japan Earthquake Sequence

Following the M7.0 strike-slip earthquake near Kumamoto, Japan, in April of 2016, most geotechnical engineering experts believed that there would be significant soil liquefaction and liquefaction-induced infrastructure damage observed densely populated city Kumamoto during post-event reconnaissance. This belief was driven by several factors including young geologic environment, alluvially deposited soils, a predominance loose sandy soils documented publicly available boring logs throughout region, high intensity ground motions from earthquake. To surprise many researchers, occurred both less frequently severely than expected. paper summarizes findings our field, laboratory, simplified analytical studies common to practice assess lower occurrence liquefaction. Measured situ SPT CPT resistance values were evaluated with current triggering procedures. Minimally disturbed samples subjected cyclic triaxial testing. Furthermore, an extensive literature review on volcanic performed. Our suggest procedures over-predict frequency effects soils. Volcanic found possess properties crushability, fines content, moderate plasticity, unanticipated organic constituents. Cyclic tests confirm these Moving forward, engineers should holistically consider soil’s mineralogy geology before relying solely when evaluating for