The hillside and road cuttings of most parts of the north,south and western regions of the Ethiopian Plateau have a record of instability.Landslide-generated problems claimed many lives and property damages in the cou...The hillside and road cuttings of most parts of the north,south and western regions of the Ethiopian Plateau have a record of instability.Landslide-generated problems claimed many lives and property damages in the country.On the road from town Fofa to Gilgel GibeⅡproject instability problem is common.Since the area is extremely rugged,the variation in the elevation is very large and展开更多
Nahaew District in northeastern Thailand, where crops out the Cretaceous Khorat Group, is a priority area for landslide hazard assessment through landslide susceptibility and hazard zoning. Through an interpretation o...Nahaew District in northeastern Thailand, where crops out the Cretaceous Khorat Group, is a priority area for landslide hazard assessment through landslide susceptibility and hazard zoning. Through an interpretation of Google Earth imagery, several landslides were mapped to create landslide inventory map. Parameter maps were constructed and compiled into a database with the landslide inventory. The bivariate (frequency ratio) statistical analysis was used to establish landslide susceptibility maps, which were classified into five susceptibility classes. Another approach was landslide hazard zonation. Urban and rural planning and engineering construction need especially hazard zonation map in medium and local scale. GIS and remote sensing techniques have many advantages in the preparation of the map including regional, medium and local scales. In this study, landslide zonation map was prepared using runout model by assigning engineering properties and Digital Elevation Model (DEM) as well as rainfall data. The result was landslide hazard zonation of the area and can be used for urban planning. The report and recommendation have contributed to local authority.展开更多
There is a great difference between the distribution and evolvement characteristics of slope geological hazard in the same geographical location and climatic conditions,taking the similar structural-genetic connection...There is a great difference between the distribution and evolvement characteristics of slope geological hazard in the same geographical location and climatic conditions,taking the similar structural-genetic connection in Wudongde reservoir area of Jinshajiang River valley for example. In all engineering geological conditions,the chronologic age and attitude of strata,and the lithologic association factors control the distributions and evolvement characteristics of slope geological hazard in the studied area. The study shows that the slopes in geological evolution are in different stages. The conclusion helps to understand the types and the intensity of geological disasters.展开更多
Rockfall is one of severe natural hazards that are frequently reported in northeast region of India. It carries rock block falling from the cliff with high velocities and energies which can result in damages to vehicl...Rockfall is one of severe natural hazards that are frequently reported in northeast region of India. It carries rock block falling from the cliff with high velocities and energies which can result in damages to vehicles, disruption to transportation, injuries and fatalities. The massive rockfall event which occurred in April 2017 on the highway NH-44 A, near Lengpui Airport, blocked the traffic for 1 d, and fortunately,no casualties were reported as the event occurred in the night. This is the only highway connecting the Aizawl city to the airport and the region is highly prone to rockfall events. Hence assessment of rockfall along this highway is necessary. In the current study, rockfall hazard assessment has been carried out on three locations by rockfall hazard rating system(RHRS). During pre-failure analysis, the result shows that most hazardous slopes have RHRS score of 639. The slopes were found to be vulnerable and later on the rockfall activity occurred. Three-dimensional(3 D) stability analysis has been carried out using 3 DEC software package to analyze the failure behavior and to decide the rockfall-prone zone(unstable blocks)for slope. The total displacement of 2.24 cm and velocity of 2,25 mm/s of the failed block have been observed in the numerical analysis. Further, the rockfall vulnerable zone(unstable blocks) is considered to determine the parameters such as run-out distance, bounce height and energies of the falling rock blocks. The maximum total kinetic energy of 5047 kJ has been observed in the numerical analysis with the maximum run-out distance up to 18 m.展开更多
文摘The hillside and road cuttings of most parts of the north,south and western regions of the Ethiopian Plateau have a record of instability.Landslide-generated problems claimed many lives and property damages in the country.On the road from town Fofa to Gilgel GibeⅡproject instability problem is common.Since the area is extremely rugged,the variation in the elevation is very large and
文摘Nahaew District in northeastern Thailand, where crops out the Cretaceous Khorat Group, is a priority area for landslide hazard assessment through landslide susceptibility and hazard zoning. Through an interpretation of Google Earth imagery, several landslides were mapped to create landslide inventory map. Parameter maps were constructed and compiled into a database with the landslide inventory. The bivariate (frequency ratio) statistical analysis was used to establish landslide susceptibility maps, which were classified into five susceptibility classes. Another approach was landslide hazard zonation. Urban and rural planning and engineering construction need especially hazard zonation map in medium and local scale. GIS and remote sensing techniques have many advantages in the preparation of the map including regional, medium and local scales. In this study, landslide zonation map was prepared using runout model by assigning engineering properties and Digital Elevation Model (DEM) as well as rainfall data. The result was landslide hazard zonation of the area and can be used for urban planning. The report and recommendation have contributed to local authority.
文摘There is a great difference between the distribution and evolvement characteristics of slope geological hazard in the same geographical location and climatic conditions,taking the similar structural-genetic connection in Wudongde reservoir area of Jinshajiang River valley for example. In all engineering geological conditions,the chronologic age and attitude of strata,and the lithologic association factors control the distributions and evolvement characteristics of slope geological hazard in the studied area. The study shows that the slopes in geological evolution are in different stages. The conclusion helps to understand the types and the intensity of geological disasters.
基金the Ministry of Earth Sciences,Government of India(MoES/P.O(Geosci)/42/2015)for the grant to carry out this study
文摘Rockfall is one of severe natural hazards that are frequently reported in northeast region of India. It carries rock block falling from the cliff with high velocities and energies which can result in damages to vehicles, disruption to transportation, injuries and fatalities. The massive rockfall event which occurred in April 2017 on the highway NH-44 A, near Lengpui Airport, blocked the traffic for 1 d, and fortunately,no casualties were reported as the event occurred in the night. This is the only highway connecting the Aizawl city to the airport and the region is highly prone to rockfall events. Hence assessment of rockfall along this highway is necessary. In the current study, rockfall hazard assessment has been carried out on three locations by rockfall hazard rating system(RHRS). During pre-failure analysis, the result shows that most hazardous slopes have RHRS score of 639. The slopes were found to be vulnerable and later on the rockfall activity occurred. Three-dimensional(3 D) stability analysis has been carried out using 3 DEC software package to analyze the failure behavior and to decide the rockfall-prone zone(unstable blocks)for slope. The total displacement of 2.24 cm and velocity of 2,25 mm/s of the failed block have been observed in the numerical analysis. Further, the rockfall vulnerable zone(unstable blocks) is considered to determine the parameters such as run-out distance, bounce height and energies of the falling rock blocks. The maximum total kinetic energy of 5047 kJ has been observed in the numerical analysis with the maximum run-out distance up to 18 m.
