This is a post Loma Prieta earthquake (Oct. 1989) investigation project in learning from this damaging event. This project studies one particular structure which faired remarkably well amidst similar buildings which suffered considerable damage during the earthquake. The Clarion Hotel complex is located in a region where high ground accelerations were measured due to the soft soil conditions near the San Francisco Airport. Interaction of the heavily reinforced pile foundation with the soil medium is suspected to have provided beneficial effects by mobilizing radiation and hysteretic damping. In addition, the pile flexibility may have provided a longer period than present in a fixed base structure. The effects of soil-pile-structure interaction on the performance of a portion of the hotel will be investigated using a complex response analysis in the frequency domain and a nonlinear time history analysis. The analysis utilizes and extends a methodology developed earlier to focus on interaction effects in an actual case. Important results expected include a comparison of the forces acting in the building and foundation elements as computed from the interactive and fixed base models, and an assessment of the period shift produced by pile flexibility.
