Title:
Experimental Study on Concrete Pile-to-Cap Connection Behavior
Author(s):
Isabella Rakestraw, John Corven, Armin Mehrabi, and David Garber
Publication:
Structural Journal
Volume:
123
Issue:
1
Appears on pages(s):
131-142
Keywords:
pile embedment length; pile-to-cap connections; precast, prestressed concrete pile
DOI:
10.14359/51749101
Date:
1/1/2026
Abstract:
Current design assumptions for precast, prestressed concrete piles embedded in cast-in-place (CIP) pile caps or footings vary across states, leading to inconsistencies in engineering practices. Previous studies suggest that short embedment lengths (0.5 to 1.0 times the pile diameter) can develop approximately 60% of the bending capacity of the pile, with full fixity potentially achieved at shorter embedment lengths than current design specifications due to confinement stresses. This study experimentally evaluates 10 full-scale pile-to-cap connection specimens with varying embedment lengths, aiming to investigate the required development length for full bending capacity. The findings demonstrate that full bending capacity can be achieved at the pile-to-pile cap connection with shallower embedment than code provisions, challenging existing design standards and highlighting the need for more accurate guidelines for bridge foundation design.
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