Abstract
This paper presents a case study of Taipingshan landslide triggered by Typhoon Saola. The Taipingshan villa is one of the most famous scenic spots at Taipingshan National Forest Recreation Area in northern Taiwan. Since early 1990s, the unstable appearances of slopes had occurred frequently in the study area, such as tension cracks, ground settlements, man-made structures cracking…etc. Therefore, a series of geological investigations and in-site/laboratory tests were carried out to estimate the slope stability and predict the rainfall threshold of landslides in 2010. The results show that the critical rainfall threshold of the case study is around 1,765 mm. In 2012, however, Typhoon Saola brought tremendous rainfall to hit eastern Taiwan. The main scarp of sliding mass B located at the History Exhibition Hall in the study area. According to in-situ extensometer data, the broken moment of extensometer shows that the real accumulated rainfall which triggered this landslide is 1,694 mm. The results of coupled analysis have been demonstrated in good agreement from the field monitoring data during the typhoon event. Our preliminary results appear to be useful for assessing the rainfall threshold of landslides. The findings can also be a good reference to establish an early warning system of landslides.
