Title:
Lap Splice Length Equation of Glass Fiber-Reinforced Polymer Bars in Flexural Reinforced Concrete Members
Author(s):
Jesus D. Ortiz, Brahim Benmokrane, and Antonio Nanni
Publication:
Structural Journal
Volume:
122
Issue:
2
Appears on pages(s):
175-188
Keywords:
bond strength; development length; glass fiber-reinforced polymer (GFRP) reinforcing bar; lap splice length
DOI:
10.14359/51742156
Date:
3/1/2025
Abstract:
This paper presents a statistically based expression derived from the existing ACI provision for determining the development and lap splice length of glass fiber-reinforced polymer (GFRP) reinforcing bars in concrete elements subjected to flexure. Missing parameters such as confining reinforcement and the differentiation between development and lap splice strength were incorporated into the base expression available in ACI CODE-440.11-22 to enhance its reliability. A database of 201 tests was used to formulate the proposed equation, aiming to prevent a splitting failure mode and resulting in a reduction in the required embedment length for typical values employed in a GFRP-reinforced concrete beam, as compared to the ACI 440 expression. The analysis of bond strength revealed an unconservative aspect in the current ACI 440 expression, particularly noticeable in lap splice tests. The proposed expression achieved an experimental-to-predicted ratio of 1.01 with a coefficient of variation of 0.180. Finally, recommendations for adoption in the next version of the Code are presented.