Seismic Site Effects Assessment of Chitwan Dun Valley
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https://doi.org/10.64862/Keywords:
Granular flow, Small-scale experiment, Particle size, Mixing ratio, Erosion and transportAbstract
The Chitwan Dun Valley, located in the central Himalayan foreland basin of Nepal, represents a seismically active region with significant potential for ground motion amplification due to thick unconsolidated sediments. This study evaluates the seismic site effects in the Chitwan Dun Valley through field microtremor surveys, geotechnical modeling, and 1-D ground response analysis. Two representative sites, Jamunapur (eastern Bharatpur) and Shantipur (western Bharatpur) were selected for representative shear wave velocity measurment. The shear wave velocity profiles, site predominant periods, and ground response parameters were determined using array microtremor data and nonlinear response analyses. Results indicate that site effects in the Chitwan Dun Valley are strongly influenced by variations in sediment composition and bedrock depth, with shorter predominant periods compared to the Kathmandu Valley.
References
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