Effect Of Marl Soil Specification On Seismic Response Of Tall Building Under Near And Far Field Earthquakes

Abstract

Marls are challenging soil types that pose a threat to the safety of construction projects. This type of soil tends to have reduced resistance and increased deformation as humidity levels rise. During an earthquake, the properties and characteristics of the soil change when it shakes. A study was conducted to assess the interaction between soil and structures during both near and far earthquakes on marls. The research focused on marly soils in the northwest region of Shiraz City. The findings indicate that for near-field earthquakes, the structural response values in non-marl regions are significantly lower compared to marly sections. Additionally, the response of drift, bending moment, and base shear for a specific cross-section is greater in high-rise buildings (e.g., 12-story buildings) compared to shorter ones (e.g., 6-story buildings). In marl sections, an increase in the thickness of marl layers leads to a higher building response. The highest response rate is observed when the thickness of the marl layer exceeds 5 meters, while the lowest structural response occurs when the thickness is 5 meters or less. Similar conditions apply for far-field earthquakes, with the distinction that the damping and frequency response of a 12-story building are greater than those of a 6-story building. This indicates that high-rise buildings are more affected by far-field earthquakes with longer periodicity.