Abstract:
This case history showcases the viability of high-capacity auger pressure-grouted (APG) piles as an alternative to the traditional deep foundation systems commonly used within the Philadelphia region (e.g. drilled shafts/caissons; driven piles; micro-piles). It demonstrates that relatively high capacities can be developed using APG piles in similar geologic settings as the subject site, and highlights circumstances where APG piles may be a favorable alternative. Included is a brief summary of the 500 Walnut Street multi-family residential development, geologic setting, and process of how APG piles were selected and implemented for support of the proposed tower. Explanations are included demonstrating how the designers arrived at the theoretical pile capacities. It also summarizes the results of the pile load test program confirming the recommended capacities, as well as the production pile installation experience.