Effects of Shaking Intensity on Seismic Site Response of Deep Soft Soils
- p71–80
The amplification of earthquake ground motion is influenced not only by the type of soil, thickness of soil cover, and depth of bedrock but also by the level of shaking. The level of shaking is a crucial parameter in strong ground motion. Many earthquake-resistant building design codes (IS: 1893: Part 1: 2016) classify seismic zones based on past and expected levels of shaking, with different zone factors for various categories. In seismic site response analysis, the site characteristic frequency is an essential parameter for investigating the seismic response of sites. Generally, the site characteristic frequency is a function of the soil profile and its properties. In this study, it is aim to explore the influence of the level of shaking on the site characteristic frequency and other strong ground motion parameters, such as peak ground acceleration (PGA) and amplification ratio. A homogeneous soft soil column is modelled in DEEPSOIL, and equivalent linear ground response analyses have been performed at shaking intensities ranging from 0.0001 to 1 g. The shift of characteristic frequency towards lower values has been observed with increasing shaking intensity. The reasons behind this phenomenon have been investigated and validated through rigorous crosschecks. Additionally, the variation of PGA and amplification ratio has been investigated, revealing a nonlinear increment with shaking intensity.
Site-Specific Performance Soil and Rock Mechanics Soil Physics Structural Geology Foundation Engineering Geotechnical Engineering and Applied Earth Sciences