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The Jure landslide or the Sunkoshi landslide, a deep-seated catastrophic landslide was triggered by a heavy rainfall at 02:36 AM on Saturday morning, 2 August 2014 in Jure Village, Sindhupalchowk District, Nepal. The huge landslide claimed 156 people, caused a seriously damages to tens of house. The landslide created a rapidly massive wave of about 100 meter towards the opposite bank of the river, which destroyed the forest area on the left bank of Sunkoshi River with a height of 100 m. The landslide velocity was estimated from 60 to 70m per second and it completely dammed the river within about 2 – 3 minutes. The catastrophic landslide also resulted in a local quake of 3.3 magnitudes. In addition, the large volume of debris about 7.4 million cubic meters blocked the Sunkoshi River and created a dam that is about 3 km long, 300 to 350 m width and 46.7 m depth. The deposited materials damaged the two gates of the Sunkoshi hydropower dam by the pressurized surging of the mud and debris. The outburst discharge and the dam breach took place on 7 September 2014. Sources: – Report on Jure Landslide, Mankha VDC, Sindhupalchowk District, Nepal Government Ministry of Irrigation, August 24, 2014, 29 pages in English. Available at http://www.sabo-int.org/case/2014_aug_nepal.pdf . – A report by Disaster Preparedness Network Nepal (DPNet Nepal). Available at http://dpnet.org.np/docs/reportManagement/c1177e6cb4970cf8b32f2a789a05d67c.pdf

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

Climate warming leads to permafrost degradation and permafrost melting phase transition, resulting in an increasing number of landslides. This study uses the road segments and road area at the intersection between Bei’an-Heihe Highway and the northwest section of the Lesser Khingan Range in north China as the study area. By means of geological survey combined with meteorological data, we analyzed the impact of climate change on landslide movement in the permafrost zone. Over a 60 year period, the average annual temperature of the study area has increased by 3.2 ◦ C, and permafrost degradation is severe. Loose soil on the hillside surface provides appropriate conditions for the infiltration of atmospheric precipitation and snowmelt, and seepage from thawing permafrost. As it infiltrates downwards, water is blocked by the underlying permafrost or dense soil, and infiltrates along this barrier layer toward lower positions, forming a potential sliding zone. The representative Landslide in the study area was examined in detail. Displacement monitoring points were set up on the surface of the landslide mass, and at the trailing edge of the landslide mass. The data collected were used to investigate the relationship between landslide movement and pore water pressure at the tailing edge as well as the ground temperature. The results show that the landslide movement process changes with the season, showing a notable annual cyclical characteristic and seasonal activity. Landslide movement is characterized by low angles and intermittence. The time of slide occurrence and the slip rate show a corresponding relationship with the pore water pressure at the tailing edge of the landslide mass. The seepage of water from thawing into the landslide mass will influence the pore water pressure at the tailing edge of the landslide mass, and is the main cause of landslide movement.

On August 8, 1979, a large translational block landslide occurred in Abbotsford – residential suburb of southwest Dunedin, New Zealand after several weeks of preliminary movements. In the history of New Zealand, the Abbotsford landslide is considered as the biggest landslide in an urbanized area. This landslide (with an area of 18 hectares and a volume of 5 million m3) moved a distance of around 50 meters down the hill at an average speed of approximately 1.7 m/min. The maximum thickness of the slide mass was up to 40 meters. No-one was injured or killed, however, the landslide caused the destruction of almost 70 houses with economic losses are around NZ $ 10-13 million. The Abbotsford landslide was contributed by two man-made factors: A sand quarry (closed 10 years earlier) at the toe of the slope and a leaking water main beyond the landslide area. Another factor which added to the initiation of the failure is high ground water levels because of the increased precipitation over the past decade. This report referred the research in the paper: Graham T. Hancox (2008) The 1979 Abbotsford Landslide, Dunedin, New Zealand: a retrospective look at its nature and causes. Landslides 5:177–188

The 1792 Unzen-Mayuyama megaslide in Japan (volume, 3.4 x 108 m3; maximum depth 400 m) killed 10,139 persons directly by the displaced landslide mass in the Shimabara area. The landslide mass also entering into the Ariake Sea where it triggered a tsunami wave. This landslide-induced tsunami wave killed 4,653 people in Kumamoto Prefecture, 343 people on Amakusa Island and 18 people in other areas (Usami, 1996). Simulations of this landslide and tsunami have already been made using LS-RAPID and LS-Tsunami in Sassa et al. (2014, 2016). Source: Sassa, K., Dang, K., Yanagisawa, H. et al. Landslides (2016). A new landslide-induced tsunami simulation model and its application to the 1792 Unzen-Mayuyama landslide-and-tsunami disaster. Landslides, First Online. doi:10.1007/s10346-016-0691-9

On 28 July 2015, around 01:00 local time, a catastrophic landslide occurred at Cao Thang ward, Ha Long city, Quang Ninh province, Vietnam. The landslide claimed 8 lives and destroyed 3 houses. It was the most significant disaster triggered by torrential rains in Vietnam in 2015. Total recorded rainfalls in a number of gauging stations in Quang Ninh province during 26-30 July were historically the highest in the last 40 years . The cumulative rainfall from 19:00, 27 July, until 07:00, 28 July was 296 mm at Bai Chay weather station in Ha Long city. The heavy rain was the main cause of the Ha Long disaster. Ha Long city is located in the center of Quang Ninh province where there is complex and diverse coastal topography including hills, delta, and islands. It is a highly urbanized and rapidly growing city (population 221,580 in 2010). Many of its people live in hilly areas prone to landslides and debris flows. The North and North East are covered by hills, containing the 70% city’s area. Altitude ranges from sea level to 504 m. Ha Long has a tropical coastal climate with two seasons. A summer season lasts from May to October; the winter from November to April. The average annual precipitation is 1800mm with 80 – 85 % of the annual average falling in summer, especially in July and August.

Landslide Umka is located 25 km south-west of Belgrade and has been researched in detail over the past 35 years, which provided extensive geotechnical documentation as well as a great number of published papers. Landslide Umka is located on the right bank of the river Sava in the crook of the large right meander before its confluence with Danube. Total length of the landslide is approximately 1700 m and its width is around 900 m. Average gradient of the slope is 9o, however, the inclination is greater in the upper sections of the terrain above the 80-85 meters above the sea level – up to 15o, while closer to the banks it is much less severe – up to 6o. Also, within the body of the landslide in the zones of the minor scarps, the gradient is greater – up to 15o. Landslide covers the area of approximately 1.8 sq km, and is in the shape of a wide fan, with volume of around 14,000,000 m3. Analysis of numerous laboratory results of research of samples taken from the colluviums, sliding planes and bedrock, defined the parameters representing their mechanical characteristics. Data analysis from inclinometer monitoring during 2005, type and amount of precipitation, temperature regimen, observation of the levels of underground waters in piezometers, as well as the measuring of levels of the Sava, allowed the conclusion that the intensifying of activity was caused by sudden increase in Sava levels, sudden thaw followed by a quick drop in Sava level. After the automated GNSS monitoring in the last six years, similar pattern was observed. Umka landslide is typical slow moving landslide with phases of intensive and slower movements, directly dependent from the precipitation regime and the levels of Sava. Reference: Abolmasov, B., Milenković, S., Marjanović, M., Đurić, U., Jelisavac, B. (2015). A geotechnical model of the Umka landslide with reference to landslides in weathered Neogene marls in Serbia. Landslides, Vol 12 (4): 689-702. DOI 10.1007/s10346-014-0499-4.

The Aso-ohashi landslide is situated at the western tip of the caldera of Mount Aso. It was named after the 200-m long Aso-ohashi bridge that formerly spanned the 80-m deep gorge of the Kurokawa River before it was destroyed by the landslide on April 16 during the magnitude 7.3 earthquake. This area is characterized by soft ground composed of weathered volcanic cohesive soil (Geological map display system of Geological Survey of Japan, AIST, 2016). The average slope angle of the sliding surface was 35.0 degrees and the average apparent friction angle was about 24.5 degrees. The maximum depth was measured as approximately 35 m. The landslide mass traveled a distance of about 800 m, deposited much debris onto National Route 57, and severely damaged a section of the JR Hohi railway track running parallel to the highway (The Japan Time 2016). This landslide also destroyed an important bridge connecting Minamiaso village to the city of Kumamoto. – – – – – Source: Dang, K., Sassa, K., Fukuoka, H. et al. “Mechanism of two rapid and long-runout landslides in the 16 April 2016 Kumamoto earthquake using a ring-shear apparatus and computer simulation (LS-RAPID)”. Landslides (2016). doi:10.1007/s10346-016-0748-9

The 2016 Kumamoto earthquakes were a series of earthquakes, including two main shocks which occurred beneath Kumamoto City, Kumamoto Prefecture, Kyushu Region, Japan. A M6.5 earthquake occurred at 21:26 JST on April 14, and a M7.3 earthquake struck at 01:25 JST on April 16 (National Research Institute for Earth Science and Disaster Resilience, NIED). The two earthquakes killed at least 49 people and injured about 3000 others. More than 44,000 people were evacuated from their homes due to the disaster. These two events generated most of the building damage and many of the landslides in the Kumamoto area. According to Japan’s Ministry of Land, Infrastructure, Transport and Tourism, at least 97 landslide locations were confirmed in the Aso area. Among these earthquake-triggered landslides, the largest landslides were two very substantial slope failures. One was located on the National Road 57 and destroyed an important bridge. The other occurred near the Aso volcanological laboratory of Kyoto University and destroyed seven houses. The Takanodai landslide includes three landslide blocks on the hillslope below the Aso volcanological laboratory of Kyoto University in Minamiaso village, Kumamoto Prefecture. The largest one destroyed seven houses of the Takanodai housing complex and killed five people (Ministry of land, infrastructure, transport and tourism). After triggering by earthquake, this landslide moved at least 150 m. – – – – – Source: Dang, K., Sassa, K., Fukuoka, H. et al. “Mechanism of two rapid and long-runout landslides in the 16 April 2016 Kumamoto earthquake using a ring-shear apparatus and computer simulation (LS-RAPID)”. Landslides (2016) . doi:10.1007/s10346-016-0748-9

The Kostanjek landslide is the largest landslide in the Republic of Croatia. It is located in the western part of the City of Zagreb, in residential area at the base of the southwestern slope of Mt. Medvednica. The landslide was mainly caused by anthropogenic factors, including mining and excavation in a marl quarry for cement production at the toe part of the landslide and blasting in a limestone quarry placed on the north of the upper part of the landslide. It is a deep-seated large translational landslide formed in soft rock-hard soil, i.e., Pannonian and Sarmatian marls. The landslide extends over an area of approximately 1.2 km2 with a total volume of displaced mass of 32.6 x 106 m3. The maximal depth of the sliding surface is 90 m. Since its activation in 1963, this landslide has caused substantial damage to buildings and infrastructure in the residential zone as well as to factories and commercial buildings. On Kostanjek landslide during the 2011-2013, within the frame of Japanese-Croatian SATREPS FY2008 project ‘Risk Identification and Land-Use Planning for Disaster Mitigation of Landslides and Floods in Croatia’, a monitoring system was established for the purpose of early warning system. The installed monitoring system consists of multiple sensor networks for the measurement of (1) external triggers (a rain gauge, a meteorological station and 7 accelerometers), (2) displacement/deformation/activity (15 GNSS sensors, 7 extensometers, 4 borehole extensometers and an inclinometer), and (3) hydrological properties (3 pore pressure gauges and 5 water level sensors in boreholes and domestic wells, and 2 water level sensors at outflow weirs).