A Time and Cost-Effective Robust Optimal Design Procedure for Structures Subjected to Uncertain Pile Driving Induced Vibrations Considering Record-to-Record Variations

Abstract With rapid urbanization, it is becoming almost inevitable to construct pile foundations for multistoried buildings in close proximity to existing structures. Such pile driving induced vibrations (PDIVs) are associated with parameters like soil properties, pile characteristics, ram velocity, etc., for which often well-defined probability distribution functions are unavailable. Furthermore, PDIV induced ground acceleration time-histories show significant record-to-record variations (RRVs) even at identical sites, hammer–pile–soil characteristics, and other input parameters. To address these issues, a new robust design optimization procedure is proposed in this study, by modeling such parameters as uncertain-but-bounded type, and incorporating RRV issues in a dual response surface method framework. A convex programming is adopted with a proposed sensitivity measure to render the design insensitive to the even highest possible PDIV uncertainty setups. The efficiency of the proposed approach is elucidated with a practical example of a 20-story reinforced concrete (RC) building. The results show that the proposed approach yields more economic and robust design solutions with fewer performance deviations than usual design procedures in a computationally efficient way. Hypersurfaces are developed to assess approximate cost requirement, possible story drift, and its dispersion for a wide range of PDIV parameters. Interestingly, it is observed that for a few cases, the PDIV may be even more critical than the seismic loading, and must be included in design standards.