STATIC AND SEISMIC BEHAVIOR OF A FRICTION PILE-BOX FOUNDATION IN MEXICO CITY CLAY

MANUEL J. MENDOZA, MIGUEL P. ROMO, MARCOS OROZCO and LEOBARDO DOMINGUEZ

ABSTRACT: A friction pile-box foundation for the support of an urban bridge in Mexico City was instrumented. The goal was to record the foundation state variables to better our knowledge of the performance of this type of foundation under static and dynamic loading. Soil-raft contact pressures, loads on selected piles, and pore water pressures in the subsoil below the foundation have been monitored from the beginning of the foundation construction until now, two and a half years after the bridge was opened to traffic. During this period, the response of the soil-foundation system was recorded during the occurrence of two seismic events in 1997. This case history yielded valuable information about the foundation performance before, during and after seismic events, regarding the analysis, design and regulations for this kind of foundation. Pile-soil-slab load sharing mechanisms are devised from these records.

Key words: case history, clay, monitoring on site/measurement, (piled box foundation), seismic observation, skin friction, soft ground (IGC: E12/Hl/T12)