Design of prestressed precast pile splice using glass fiber reinforced polymer (GFRP) dowels

Abstract

For various reasons including shipping and operation limitations and unforeseen soil conditions, it often happens that splicing of precast-prestressed concrete pile (PPCP) segments has to be performed at the site to achieve longer lengths. Epoxy dowel splice is one of the common systems used for splicing PPCPs. The objective of this study was to investigate the effectiveness of glass fiber reinforced polymer (GFRP) dowel bars proposed as an economic corrosion-resistant option for use in pile splices. Analysis was performed for a standard 18×18 in (457×457 mm) PPCP. Two series of material properties were considered for GFRP in the proposed design, mechanical properties in accordance with the Florida Department of Transportation (FDOT) Specifications and improved mechanical properties (2021) under consideration by ASTM D30 Committee. The results show that among various sizes and configurations, the use of 8 #10 GFRP dowels with arrangement similar to that of standard steel dowel splice provides for an optimum design. As an example, the developed design was compared to FDOT requirements. The proposed configuration of GFRP dowels satisfies the requirement for axial compression and tensile capacities. The nominal pure bending capacity of the proposed design is estimated to be 84% and 93% of the threshold capacity for the existing material and improved material, respectively. The flexural resistance of the splice increases with increasing axial compression on the pile to an extent. The use of improved GFRP material for dowel bars shows noticeable enhancement in the flexural resistance so as the use of larger diameter dowels. Detailed drawings for the proposed design were also developed and are presented in this paper.