The Montana Department of Transportation (MDT) has found concrete-filled steel tube (CFST) piles connected at the top by a concrete pile cap to be a very cost-effective support system for short and medium span bridges. This type of system offers low initial cost, short construction time, low maintenance requirements, and a long service life. While the gravity load performance of these systems is well understood, their strength and ductility under extreme lateral loads (e.g., seismic events) is more difficult to reliably predict using conventional design procedures.

MDT has sponsored previous WTI research to investigate the performance of these systems under extreme lateral loads and to develop appropriate analysis/design procedures. The primary objective of this research, led by Michael Berry, is to further validate/improve MDT’s CFST to concrete pile cap connection design/analysis methodologies, and to ensure the efficacy of these methodologies for a wide variety of potential design configurations. This research has important potential benefits for evaluating and enhancing bridge performance during earthquakes and other seismic events.

Additional information is available on the project page of the WTI website.