Research Projects

The seismic performance of reinforced concrete (RC) structures is significantly influenced by soilstructure interaction (SSI), whether built on flat ground or slopes. Many structures failed on slopes during the previous 2015 Nepal earthquake, 2023 Turkey earthquake, etc. Traditional seismic analysis often assumes that the foundation soil is rigid, neglecting the elastic properties of the underlying soil (Debnath et al. 2022, 2023; Dutta et al. 2021). The PI has also recently contributed to the research considering RC structures on slopes with fixed base (Kumar et al. 2025). This approach does not consider SSI and the variability of ground motion parameters, focusing only on the structural dynamic parameters. However, it is realized that when a building is constructed on soft soil, its response during seismic events can differ significantly, making SSI a crucial factor in earthquake performance due to the dynamic interaction between soil and structure. Although earthquake ground motion parameters are regularly considered in seismic design, their impact on buildings with SSI, especially under nonlinear conditions, is not well understood. (Hamidia et al. 2021; Saha et al. 2020). Different nearfault and far-field earthquakes also result in variations in frequency content, amplitude, and duration of ground motion, all of which influence the structural behavior. So, this research will explore the impact of SSI and ground motion characteristics on the seismic performance of RC buildings on slopes. The project will develop a 3D finite element model of a typical RC building on slopes and its foundation system, integrating both structural elements and the underlying soil domain using advanced computational models and finite element analysis, like PLAXIS 3D. It will comprehensively analyze how soil properties (such as stiffness and damping) and ground motion characteristics (such as amplitude, frequency, and duration) affect building response during earthquakes. The study will analyze how various soil types—soft, stiff, and layered—affect the building’s seismic vulnerability, with additional consideration of varying water content. This project will contribute to safer building designs in seismic zones IV & V on slopes like the Himalayan belt. Incremental dynamic analysis will be performed for seismic loading, and fragility curves will be drawn to assess vulnerability. The novelty of this research lies in its innovative approach to SSI modeling, realistic soil-structure simulations, parametric investigations under different earthquake motions, and bridging the gap between theoretical analysis and engineering practice, helping government initiatives like the Smart Cities Mission or NDMA guidelines, emphasizing impact of proper planning and designing on reducing seismic vulnerability. This work is among the first in India to integrate SSI, ground motion variability, and slope effects into a unified probabilistic vulnerability framework.