Haivan Station Landslide

Hai Van station is located on the sea side-slope of Hai Van pass at the height of 127 m. Every day, there are over 30 trains pass through this station. However, this area is often affected by landslides, for example landslides in the years of 1999, 2005, and 2007. This landslide is the biggest landslide in Hai Van Mountain with the length of 1040 m, and depth of displaced mass of 100 -120 m. Three bore holes (BH1 with 30 m depth, BH2 with 60 m depth, BH3 with 80 m depth) and some monitoring equipment such as rain gauges, extensometers, inclinometers have been carried out in this area to survey geology, observe rainfall and displacement of the landslide mass. The daily variation of rainfall and slope displacement from 10 May 2013 to 17 January 2014 was observed. The accumulative displacement in this period is around 19 mm and the large displacement observed after the heavy rainfall period from 18 September 2013 to 16 November 2013. It indicates that Hai Van station landslide is an active landslide with slow movement and failure may occur in the future. In the computer simulation of the active landslide in Viet Nam, failure started from a middle point of the slope when the pore-water pressure ratio (ru) reached the value of 0.31. The total landslide volume and the vertical maximum depth of the landslide were calculated to be 24057.9 x 103 m3 and 111 m, respectively. Source: Dang K (2015) Development of a new high-stress dynamic-loading ring-shear apparatus and its application to large-scale landslides. Doctoral Thesis, Graduate School of Engineering, Kyoto University. 79 pages