Pounding Risk Assessment through Soil–Structure Interaction Analysis in Adjacent High-Rise RC Structures

Abstract

This study investigates the seismic response of two 20-story adjacent reinforced concrete structures with differing lateral load-bearing systems, emphasizing the influence of soil–structure interaction. In total, 72 numerical models explored the combined effects of 9 earthquake motions, 4 soil types, and 2 structural designs. Analytical fragility curves revealed superior seismic resilience for the structure with shear walls compared to the bare frame structure. Shear walls increased the capacity to withstand earthquakes by up to 56% for each damage level. Soil behavior analysis investigated the effect of soil properties. Softer soil exhibited larger deformations and settlements compared to stiffer soil, highlighting soil ductility’s role in the system’s response. The study further assessed potential pounding between structures. The connection between structural stiffness and soil deformability significantly affected pounding risk. The provided gap (350 mm) proved insufficient to prevent pounding under various earthquake scenarios and soil types, leading to damage to RC components. These findings emphasize the crucial need to consider both structural systems and soil properties in seismic assessments.

Keywords

• soil–structure interaction
• fragility curve
• high-rise building
• dynamic analysis
• RC shear wall