Application of stress wave theory to evaluate the bearing capacity of steel pipe piles

This paper describes the evaluation of the dynamic bearing capacity of a driven pile by application of the wave theory combined with site measuring of stress and velocity of the pile during installation. In 1989, Kawasaki Steel has introduced PDA (Pile Driving Analyzer; measuring and analysis device) and CASE and CAPWAPC (analysis software), and made continuous research of this system on the bearing capacity of the full scale steel pipe pile in various aspects. By selecting suitable redriving energy and timing, bearing capacities between values estimated by the PDA system and values obtained by the static loading test showed a good correspondence within an error range of 5 to 10%. Results of application to two actual construction sites proved good applicability as a dynamic bearing capacity control system considering the recovery behavior of shaft resistance during the time elapsed.