Showing 3 results for Type of Study: Other
Volume 1, Issue 1 (7-2003)
Abstract
(Paper pages 24-41 ) Different methods are used for landslide hazard zonation. Some of the methods are based on specific condition of the area. In this research, applicapibility of a number of landslide hazard zonation methods in Latian Dam watershed is evaluated. For this purpose Latian Dam watershed due to variety in geological condition, engineering geological characteristics, topography, geomorphology, and precipitation was selected. Different thematic layers including geology, distance from active faults, elevation, slope rate and aspect, precipitation, and vegetation cover were prepared. More than 150 single and landslide zones were recorded based on aerial photo interpretation and field survey. The data were analyzed to find out about landslide controlling factors. Considering instability controlling factors, Nilsen, Information Value, Weight of evidence, and Density area methods were used for preparation of landslide hazard zonation in the watershed. The comparison of the prepared hazard zonation maps with landslide inventory map indicates that weight of evidence and information value methods with accuracy of 99.4 and 99.7 percent respectively are most appropriate methods for preparation of landslide hazaed zonation map in similar area in Central Alborz.
B B, M Kh, ,
Volume 4, Issue 1 (11-2010)
Abstract
Gotvand dam reservoir with over 90 km length is surrounded by Gachsaran, Mishan, Aghajari and Bakhtiari formations. The noticeable point in the dam reservoir is the presence of Gachsaran Formation that is composed of considerable volume of salt located 4 km upstream of dam. Salinity of dam water due to dissolution of salt in reservoir water can cause serious environmental problems. In addition to direct dissolution of salt in contact with reservoir water, slope instability can also influence on this process. Probable sliding in salty layers of slopes will insert a significant volume of salt in contact with reservoir water in a short time. In order to study the land-sliding process in reservoir area and also analysis of the effect of dissolution of salty layers on sliding, characteristics of dominant material engineering of mass constituent were defined by rock mechanics experiments. Then the results of performed tests on rock samples and GSI method were used to estimate the engineering parameters of rock mass. To investigate the land-sliding process in reservoir area and also the effect of dissolution of salty layers on sliding, some salt samples were transferred to the laboratory. Using circulation method, solubility of those samples were examined in different conditions. The results were generalized to the reservoir condition. Eventually, slope stability were analyzed by modeling with SLIDE software, considering different levels of reservoir water, influence of dissolution of salty layers. The obtained results indicate that slidings in reservoir area are mostly shallow and are caused by dissolution of salty layer.
S Afshar, M Ghafori, Gr Lashkaripur, M Arian, M Musavimadah,
Volume 6, Issue 1 (11-2012)
Abstract
With respect to development of underground structures and their high construction costs in intra- and inter-municipal transportation, it is necessary to study the stability of such structures. In this research, tunnel stability of Mashhad Metro line 2 with 17 km length is studied. First, the type of sediments and geotechnical properties in Mashhad Plain are investigated. The SPT profiles were prepared using Rock Work 2006 software. The soil classification tests and XRD results show that the soils in this line are mostly clay such as Illite and Kaolinite types. Afterwards, because most of the soils in this line are characterized as fine grained, the ground settlement using PLAXIS V8 software was performed. According to the numerical modeling and the depth of tunnel, the optimum depth for tunnel was determined.
