Post-tensioned splice system for precast, prestressed concrete piles: Part 3, capacity verification from laboratory and full-scale testing

Splicing precast, prestressed concrete piles has historically been difficult because the attachment detail requires either preplanned considerations and cast-in connection details or onsite coring and doweling when unplanned pile extensions arc needed. When the piles are driven after splicing, the splice connection is prone to tensile failures due to the inability to transfer tensile driving stresses through the connection and into the other pile segment. Focusing on preplanned splices, the Florida Department of Transportation limits tension stresses during driving to 250 and 500 psi (1700 and 3400 kPa) for epoxy dowel splices and mechanical splices, respectively. This can limit the ability to efficiently drive the pile to the point that it may even he impossible. In response to the need for a more robust splicing methodology, an alternative pile-splicing approach incorporating post-tensioning was developed. The concept eliminates the limitations on tension stresses during driving. This is the third of three papers that details the development and implementation of the new approach into a prototype system. This involved laboratory and full-scale studies and subsequent ultimate load verification tests. The findings show that the concept is scalable and implementable in commercial facilities with minor adjustments.