Chandra Kiran Kawan, Amit Prajapati, Dinesh Sakhakarmi
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引用次数: 0
Abstract
Bhaktapur city, one of the historical cities of Nepal, is among the old settlements within Kathmandu Valley that were frequently devastated during major earthquakes. Historical evidence clearly states the high seismic vulnerability of Bhaktapur. So, this study characterizes the free field of the Bhaktapur district in terms of periods. For this, the horizontal to vertical (H/V) technique was used to determine the predominant period of the study area, measuring microtremor data at 200 m × 200 m spacing in the core city area, whereas 400 m × 400 m spacing of measurement was done at the outskirts of the city with rare settlement. The spatial distribution map of the predominant period is prepared with the period obtained from 609 measuring points. The map shows that the predominant period ranges from 0.1 to 4 s and then categorized into four different zones—A (0.10–0.6 s), B (0.6–1.0 s), C (1.0–1.7 s), and D (1.7–4.0 s). The central parts of the study areas are spotted with longer periods (1.7–4.0 s), where the density of the dweller is high. The structural period of 28 reinforced concrete buildings was also determined to understand the level of danger of the buildings due to soil-structure resonance. The predominant period of the buildings ranges from 0.12 to 0.42 s. The possibility of soil structure resonance condition is higher for six buildings, medium for two buildings, and low for the rest of the buildings. The results can be applied to urban planning, seismic hazard mitigation, conservation, and restoration of heritage monuments.
期刊介绍:
Journal of Seismology is an international journal specialising in all observational and theoretical aspects related to earthquake occurrence.
Research topics may cover: seismotectonics, seismicity, historical seismicity, seismic source physics, strong ground motion studies, seismic hazard or risk, engineering seismology, physics of fault systems, triggered and induced seismicity, mining seismology, volcano seismology, earthquake prediction, structural investigations ranging from local to regional and global studies with a particular focus on passive experiments.