About KUWANO REIKO
About 東大 生産技研
About 地盤工学会誌
About underground opening
About falling
About road
About road surface
About waterway
About shallow groundwater
About sewer pipe
About calcareous soil
About volcanic ash soil
About ground subsidence
About earth surface
About water channel
About cave-in in the road
About cavity under road surface
About Other disasters
About 陥没
About 地盤
About 空洞