Suggested Method to Predict Catastrophic Landslides

1994年（1）来自加拿大、英国、新西兰、斯里兰卡和中国在京都举行了为期两周的联合研究会议，并在日本长崎县的马郁山滑坡区进行了联合实地调查。1995（2）Sassa和Fukuoka与加拿大地质调查局的Evans一起对加拿大的Frank Slide进行了调查。梯田土壤取样从那里的幻灯片逃跑，并带到日本。他们对该样品进行了不排水加载环剪切试验，以预测滑坡运动，发现表观摩擦角仅为3.8度，这可以解释其长期运行。埃文斯通过钻孔在弗兰克滑坡的堆积物下面发现了剪切层。(3)Sassa、Fukuoka和Evans联合调查了1995年1月17日日本兵库县南部地震引发的西宫的Nikawa滑坡。他们在那里取样，进行不排水循环加载环剪试验。结果表明，滑面液化是由于土体结构破坏和颗粒破碎造成的。这一现象可以解释滑坡体的快速运动。(4)来自加拿大，英国，新西兰、美国和意大利在京都大学召开了为期两周的联合研究会议，讨论了滑坡预测和评估的实用方法。1996（5）福冈县佐对1996年12月6日的甘原泽泥石流灾害进行了实地调查。他们从最近的溪流中采集了激流沉积物的样本。不排水环剪试验结果表明，滑面发生液化并引发高速剪切，这可以解释滑坡触发泥石流的机制。Sassa在IUGS（国际地质科学联合会）会议上与美国和加拿大的调查人员和联合研究人员讨论了结果。

1994(1) Investigators and joint researchers from Canada, U.K., New Zealand, Sri Lanka, and China held a joint research meeting for two weeks in Kyoto, and made a joint field investigation in Mt.Mayu Landslide area, Nagasaki Prefecture, Japan.1995(2) Sassa and Fukuoka investigated Frank Slide, Canada with Evans of Geological Survey of Canada. Terrace soils were sampled from where the slide ran away and brought to Japan. They carried out undrained loading ring shear tests for predicition of landslide movement with the sample and found that the apparent friction angle was only 3.8 degrees, which could explain its longrunout. Evans found sheared layr beneath the deposited mass of the Frank Slide by boring.(3) Sassa, Fukuoka and Evans jointly investigated the Nikawa landslide, Nishinomiya, Japan which was triggered by the 17 January 1995 Hyogoken-Nambu earthquake. They sampled soils there and carried out undrained cyclic loading ring shear tests. Results showed "sliding surface liquefaction" occurred due to destruction of soil structure and grain crushing. This phenomenon reduced the shear strength rapidly and dramatically and could explain the rapid landslide motion.(4) Investigators and joint researchers from Canada, U.K., New Zealand, United States, and Italy gathered at Kyoto University and held a joint research meeting for two weeks, and discussed on the practical method of landslide prediction and assessment.1996(5) Sassa Fukuoka carried out field investigation of the 6 December 1996 Gamaharazawa Debris Flow Disaster. They sampled torrent deposits from the nearest stream. Undrained ring shear tests on the sample revealed that the sliding surface liquefaction occurred and initiated high speed shearing, which could explain the landslide triggered debris flow mechanism. Sassa discussed the results with Investigators and joint researchers form United States and Canada at the occasion of IUGS (International Union of Geological Sciences) meeting.