Pile Driving Effects on a Steel Truss Railway Bridge During Rehabilitation

ABSTRACT: This paper summarizes the performance of a steel truss railway bridge near Saskatoon, SK, which remained in service during pile driving for rehabilitation. Over 500 H piles were driven to approximately 8 m for existing piers, and 11 m for new piers, over an approximate one-month timeline. Survey, tilt loggers, and vibration monitoring were used to monitor the lateral deflection and accelerations of the structure. Effects on the structure from pile driving into the very hard glacial till foundation soil is discussed. WEAP analysis was conducted to estimate termination criteria and driving hammer performance. Pile Dynamic Analyzer (PDA) testing was conducted on 10% of the piles, with resistances measured as high as 60% more than the design ultimate resistance. Hypotheses regarding the discrepancy between design and measured resistance are presented.