picture taken under a bridge structure

The Montana Department of Transportation has found concrete-filled steel tube (CFT) 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. The proposed research aims to further develop newly established design and analysis methodologies, and to ultimately ensure the desired bridge performance.

Phase I: Preliminary Investigation

Final Report

Phase II: Lateral Load and Lateral Displacement

Final Report
Implementation
Project Summary Report

Phase III: Confirmation of Connection Performance

Final Report
Implementation
Project Summary Report
Performance Measures Report
Kappas, L. (2018). Performance and Design of Steel Pipe Pile to Concrete Cap Connections Subject to Seismic or High Transverse Loading
"A design aide was developed in Excel to assist with the proposed algorithm and calculations of subsequent internal connection forces between the embedded steel pile and the concrete pile cap, as described in portions of the provided dissertation. This design aide may be useful to assist with design of a pile-to-pile cap connection if used appropriately. The design aide’s results are based on the experimental findings of the research and would require verification for other specific applications. Additional work is ongoing to verify the design of these connections and design aide. Please contact Lenci Kappes, 406-444-6932, with questions about this design aide and accompanying information."
2016 TRB Annual Meeting Poster

Phase IV: Further Evaluation/Improvement of Analysis/Design Methodologies

Final Report (pending)
Final Presentation (pending)
Project Summary Report (pending)
Implementation Report (pending)
Performance Measures Report (pending)
Poster (pending)