RECONNAISSANCE ON LIQUEFACTION-INDUCED FLOW FAILURE CAUSED BY THE 2018 MW 7.5 SULAWESI EARTHQUAKE, PALU, INDONESIA

Hidayat, Risqi Faris (Geo-disaster Mitigation Engineering Laboratory, Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 113-8656,)
Kiyota, Takashi (Geo-disaster Mitigation Engineering Laboratory, Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 113-8656,)
Tada, Naoto (Disaster Risk Reduction Expert, Japan International Cooperation Agency Indonesia Office, Sentral Senayan II, 14th Floor, Jalan Asia Afrika No. 8, Jakarta 10270, I)
Hayakawa, Jun (Ministry of Land, Infrastructure, Transport, and Tourism, 2-3-1 Kasumigaseki, Chiyoda-ku, Tokyo,)
Nawir, Hasbullah (Department of Civil Engineering, Faculty of Civil and Environmental Engineering, Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132)

Journal of Engineering and Technological Sciences
Vol 52, No 1 (2020)

The Mw 7.5 Sulawesi Earthquake 2018 was a catastrophic disaster that resulted in large numbers of casualties. This study aimed to investigate the damages of liquefaction-induced-flow failure in three areas in Palu city, i.e. Petobo, Balaroa, and Jono Oge. It was found that this flow failure occurred on a large scale at a very gentle ground inclination, ranging from 1 to 3%. In order to gain an understanding of the soil conditions in these specific locations, Portable Dynamic Cone Penetration Tests were conducted in Petobo. The results showed that the soil layers in the affected area were in a loose state compared to the non-affected areas. Furthermore, some spots of freshwater inundation were recognized in Petobo and Balaroa, even two weeks after the disaster. Based on this evidence, a mechanism of liquefaction-induced-flow failure caused by a confined aquifer is proposed.