Seismic site characterization for Moulvibazar town, Bangladesh

In recent years, decision-making and site-planning strategies for earthquake mitigation have shifted away from a crisis management approach, to a greater emphasis on risk reduction. The earthquake hazard of a particular area can be assessed using geophysical and geotechnical site investigations. In the present study, seismic site characterization was carried out to evaluate earthquake risk for the town of Moulvibazar, Bangladesh, by integrating geophysical and geotechnical approaches. The study revealed that the average shear wave velocity to a depth of 30 m (AVS30) varied from 150 to 235 m/s, and US National Earthquake Hazards Reduction Program (NEHRP) soil site classes D and E were predominant, with soil amplification factors (SAF) of 1.3 and 1.45 for site classes D and E, respectively. In addition, peak ground acceleration (PGA) at the ground surface ranged from 0.325 to 0.3625 g, foundation layer depths for the deep foundation varied from 15 to 29 m, and the predominant periods ranged from 0.35 to 0.72 s. These soil parameters can be used to prepare an earthquake risk-sensitive land use plan for future urban development and to design earthquake-resistant structures.