August 20, 2019

Date:August 20, 2019
Location:e-Asia Landslide Field Excursion in Kyushu

We had a field excursion at two landslide site at Murobaru landslide in Kumamoto Prefecture and Yabakei landslide in Oita Prefecture.

Stop 1 Murobaru landslide (33°08′18″N, 130°59′10″E)
Guide: Mr. Tosa, S., Mr. Kawashima, M., Mr. Nishikubo, F. (Japan Conservation Engineers & Co., Ltd.)

The Murobaru landslide is one of the largest landslides in Kumamoto Prefecture, which has 1,000-meter length, 350-meter width, and 80-meter depth. We observed the drainage wells and the observation systems such as inclinometers and pore water pressure gages.

Stop 2 Yabakei landslide (33°24′24″N, 131°05′54″E)
Guide: Mr. Hayashi, ○. (Oita Prefectural Government)
Mr. Tosa, S., Mr. Nishikubo, F. (Japan Conservation Engineers & Co., Ltd.)

The Yabakei landslide occurred in April 2018, and six people were killed by landslide debris. The scale of the slide has 220-meter length, 160-meter width, and 35-meter depth. The characteristic of the slide was rapidly and non-rain induced landslide. We discussed not only landslide causing mechanism but also Japanese advanced countermeasure works for a secondary landslide.

We received generous support from Kumamoto Prefecture, Oita Prefecture, and Japan Conservation Engineers & Co. Ltd. I want to offer our special thanks to the above organizations.