A chain event of the 2016 Kumamoto earthquakes caused considerable
geotechnical damage related to liquefaction in many places around Kumamoto
plain. Many low-rise houses and traditional Japanese style houses, which were
constructed on shallow foundation,
suffered differential settlement and tilting due to liquefaction. To mitigate
the building damages due to the liquefaction, a new countermeasure method of jet grout grid form
with a horizontal slab is introduced in this study.？The effectiveness of the proposed technique was evaluated through
physical modelling and numerical modelling. As a part of the physical modelling,
a set of 1 g shaking table tests for unimproved case and improved case were performed, in which the mitigation effects of the
grid form with a horizontal reinforcing slab were examined based on the acceleration,
excess pore water pressure ratio as well as ground settlement. Numerical
simulation was also performed for assessing the effect of improved method on soil-structure interaction
and building settlement during the
earthquake. The physical and numerical results confirmed that
the grid form with horizontal slab
reinforced method is effective in settlement control and offers favorable
contribution
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