Seismic hazard evaluation using site response analysis and amplitude parameters at Hawassa town, Main Ethiopian Rift.

Ground motion from an earthquake is the most devastating geo-hazard in seismically active areas as it affects human life and infrastructure as well as their day-to-day activities. Hawassa town has faced distress of building due to earthquake of small to intermediate magnitudes. The main aim of this study is to predict ground motion parameters using DEEPSOILV.7 program. For this purpose, linear, equivalent linear, and nonlinear approaches at five sites were applied. In this study, the natural period (T30) and amplification (A30) of the site were used to determine the amplification. Two input ground motions from the DEEPSOILV.7 software were used to generate site's PGA (g), spectral acceleration (PSA) (g), maximum strain (%), and amplification factor (AF) at the surface. In addition, T30 and A30 maps at a depth of 30 m were prepared by krigging interpolation techniques. The PGA (g), AF, and maximum strain (%) and PSA (g) showed the amplification at a shallow depth for the input motion at four sites but deamplification at one sites. The highest maximum strain (%) values were observed at a shallow depth indicating the probability of liquefaction induced ground deformation. The T30 and A30 map showed a long period and high amplification in the northern part but a short period and low amplification in the southern part. The results of this study will be used at local, zonal, regional, and federal levels for the design of critical structures as it provides first-hand information on the seismic hazard of the area. [ABSTRACT FROM AUTHOR]