3D Numerical Lateral Pushover Analysis of Multiple Pile Group Systems

In the development of a performance-based design approach for pile groups, it is important to identify aspects that may have significant effects. To achieve that objective, a series of 3D numerical lateral pushover analyses of pile groups is performed, and the results are subsequently evaluated and synthesized. The effects of pile structural capacity, soil conditions, and foundations systems (single pile groups and multiple pile group systems) are examined explicitly. The highlighted observations include: 1) the structural performance criteria of piles as structural elements alone may not be directly applicable for pile group systems, 2) the performance criteria for the pile group systems would need to consider explicitly the soil conditions, 3) the behavior of pile groups in softer soils appears to be displacement-controlled, while that in stiffer soils appears to be force-controlled, and 4) the progression of plastic hinge development would not most likely lead to a sudden decrease in the pile group system stiffness.