Liquefaction-Induced Damage in Recent Earthquakes and New Countermeasures against Liquefaction

摘要

This paper focuses on new countermeasures against liquefaction. Firstly, an overview of liquefaction triggered by the 2016 Kumamoto earthquake in Japan is presented. The tilt angle of 68 houses and buildings in liquefied areas in Kumamoto City was measured as liquefaction-induced damage to residential houses. Next, shaking table tests in a 1-g gravity field concerning on new countermeasures against liquefaction are introduced here. One of them is a log pilling into a liquefiable sand layer against the settlement of structures during earthquake. Shaking table tests were conducted using the model ground to clarify the effects of installing logs into liquefiable sand layer and relationship between duration time of shaking and settlement of structure. Another method is geosynthetics along with gravel installed at liquefiable ground. The effects of the gravel and geosynthetics were evaluated.