Soil Structure Interaction in Practice

Abstract

Seismic incidents of recent decades have evoked extensive studies focusing on the effects of Soil-Structure Interaction (SSI). Rodriguez and Monies [1] evaluated the importance of SSI effects on the seismic response and damage of buildings in Mexico City during the 1985 earthquake. A simple structural model was used to conduct a parametric study using a representative record obtained in the soft soil area of Mexico City. The results indicated that in many cases of inelastic response, SSI can be evaluated considering the rigid-base case and the amplified period of the SSI system. A similar procedure can be followed to assess seismic damage in multi-story buildings supported on flexible soils. Literature in the area is rather extensive. This brief introduction gives only a flavour of issues in recent studies on the topic. Based on an observation on the damage pattern caused by the 1994 Northridge earthquake, that is that the number of severely damaged buildings was reduced in areas where the surface soil experienced some form of non-linear response, Trifunac and Todorovska [2] studied the effects of non-linear soil response. They attempted to quantify the relationship between the density of red-tagged buildings and the severity of shaking, including the density of breaks in water pipes as a variable specifying the level of strain in the soil.