QE69 : Liquefaction hazard microzonation in the coastal areas of Bandar Abbes
Thesis > Central Library of Shahrood University > Geosciences > MSc > 2011
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Abstarct: Very damages which are caused from earthquakes, are related to seismic geotchnic. One of these phenomena, saturated soil liquefaction during an earthquake, is a non-compact type of fine-grained sand or coarse sediment is observed. Considering the high seismicity conditions, high groundwater levels and soil characteristics, the eastern part of Bandar Abbas City for the occurrence of high liquefaction potential is high.
Liquefaction hazard potential in this sector, an area about 12 kilometers east coast city of Bandar Abbas, has been evaluated baxsed on geotechnical data. Given the importance of geological and soil conditions in the occurrence of liquefaction, the soil in this area by field observation, drilling boreholes and 1:20000 scale aerial photographs were evaluated. Then the map using the local groundwater levels and water levels recorded in boreholes during drilling, was drawn. In this study data from 30 exploration boreholes such as standard penetration test (SPT), aggregation and soil classification, has been used as a baxse. Detailed and systematic study of the potential for liquefaction risk, study area, 500 meters to 500 meters, divided into grids and soil properties were estimated in each network. In order to evaluate the liquefaction potential, method of Seed et al (2003) use of liquefaction safety factor (FS) was calculated for different depths. Than potential indicators liquefaction (PL) and the Iwasaki et al (1982) method were obtained for each borehole. In this study, the acceleration 0.35g , which designs buildings in earthquake regulations set for the city of Bandar Abbas, has been used as the bedrock acceleration. Regulations for the acceleration of the earth's surface, but as a conservative value in this study have been attributed to the bedrock. Then using EERA software acceleration level was determined baxsed on its reliability and liquefaction potential index was calculated.
Investigation showed that the soil is mostly sandy soil of study area and is of type SM and SP. Also check the water level indicates a change in water level is in this range. The beach near the water surface with 0.5-1 m away from the beach, in the West and North West of the city also reaches 15-20 m. According to the survey, part of the city of Bandar Abbas is located between the coastal line to the central area has a potential indicator of more than 15, which represents a high risk of liquefaction is in this range. Thus, for make of different structures,detail studies for reduce of liquefaction hazards, is essential. The study area of north central range with the exception of a limited number of channels and rivers in the privacy of 50 meters that is considered at risk of liquefaction potential is zero and the other networks generally do not require detailed studies.
Keywords:
#Earthquake #liquefaction #Bandar Abbas #the standard penetration test Link
Keeping place: Central Library of Shahrood University
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Keeping place: Central Library of Shahrood University
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