International Concrete Abstracts Portal

Title: Self-Consolidating Concrete Piles Confined in FRP Tubes

Author(s): H. El-Chabib, M. Nehdi, and M. H. El Naggar

Publication: Special Publication

Volume: 209

Issue:

Appears on pages(s): 297-318

Keywords: bending; compression; concrete; fiber-reinforced; piles; plastic; self-consolidating; stress-strain

Date: 9/26/2002

Abstract:
Cast-in-place deep foundations such as drilled shafts and piers are often subjected to two sources of problems. First, the integrity and uniformity of the cross-sectional area of these structural elements cannot be assured using normal concrete because of limited accessibility and visibility during construction. Cavities and soil encroachments leading to soil pockets can jeopardize their load-bearing capacity. Second, corrosion problems of steel reinforcement in deep foundations have been costly, requiring annual repair costs of more than $2 billion in the US alone. To address these two challenges, a novel technology for the construction of drilled shaft concrete piles is proposed in this study. Self-consolidating concrete, a material that compacts under its self-wight without vibration and without bleeding or segregation, is used to assure the structural integrity and uniformity of the cross-sectional area of deep foundations. The self-consolidating concrete is cast into FRP envelopes, which provide corrosion-resistant reinforcement. This paper presents results of a laboratory investigation on the mechanical performance of these novel piles including the effect of using expansive cement and shrinkage-reducing admixtures to enhance the FRP tube-concrete interfacial bond.