Confinement of RC Elements by Means of EBR FRP Systems

Abstract

This chapter reviews the issues of confinement in plain and reinforced concrete under concentric compression and summarizes the state of the art regarding the available confinement models for strength and stress-strain behaviour of encased confined concrete, and the corresponding magnitude of dependable strain capacity. The mechanisms of confinement failure, the evolution of Poissons’ effects under low and high confinement, and the ensuing material compaction at high confining pressures (plastification) are discussed. The effects of stress concentrations near corners, the effectiveness of layers and influence of adhesive, other scale effects and the influence of specimen morphology on mechanical behaviour are also outlined. Next, the chapter concentrates on the effects of embedded reinforcement both longitudinal and transverse. Confinement effectiveness in the presence of combined flexure and shear (in plastic hinge regions), local effects due to rotation capacity increase, and effects of FRP confinement on overall member behaviour are discussed. Shape effects that occur in hollow or oblong sections are also considered. Furthermore, the chapter gives an outline regarding the characteristics of the international database of tests for confinement, and its calibration with the database of the available confinement models including those included in the design standards (ACI, CNR and EC8-III).

Appendix: List of Sources for Database Specimens

Characteristics and experimental results for 219 FRP confined circular columns without steel reinforcement (Table 5.A-(i), in supplementary material) shown in Arduini et al. (1999), Berhet et al. (2005), Carey and Harries (2005), Harmon and Slattery (1992), Harries and Carey (2003), Kono et al. (1998), Li et al. (2003), Matthys et al. (1999), Micelli et al. (2001), Miyauchi et al. (1997), Pellegrino et al. (2004), Pessiki et al. (2001), Picher et al. (1996), Rochette and Labossiere (2000), Rousakis (2001), Shahawy et al. (2000), Silva and Rodrigues (2006), Teng and Lam (2004), Tinazzi et al. (2003), Toutanji (1999), Wang and Wu (2008), Watanabe et al. (1997) are included in the database (a).

Characteristics and experimental results for 77 FRP confined circular columns with steel reinforcement (Table 5.A-(ii), in supplementary material) shown in the works of Arduini et al. (1999), Carey and Harries (2005), Demerse and Neale (1999), Esafhani and Kianoush (2004), Ilki et al. (2008), Li et al. (2003), Lin and Liao (2004), Matthys et al. (2006), Parretti and Nanni (2002), Pellegrino et al. (2004), Pessiki et al. (2001), Rodrigues and Silva (2001), Tinazzi et al. (2003) are included in the database (b).

Characteristics and experimental results for 135 FRP confined rectangular columns without steel reinforcement (Table 5.A-(i), in supplementary material) shown in the works of Braga et al. (2004), Campione (2006), Chaallal et al. (2003), Harajli 2006, Harries and Carey (2003), Ilki and Kumbasar (2003), Mirmiran et al. (1998), Mukherjee et al. (2004), Parvin and Wang (2002), Pessiki et al. (2001), Rochette and Labossierre (2000), Rousakis et al. (2007), Wang and Wu (2008) are included in the database (c).

Characteristics and experimental results for 156 FRP confined rectangular columns with steel reinforcement (Table 5.A-(ii), in supplementary material) shown in the works of Braga et al. (2004), De Paula and Da Silva (2002), Esfahani (2004), Feng et al. (2002), Harajli et al. (2006), Hosseini and Fadaee (2004), Ilki et al. (2008), Maalej et al. (2003), Parretti and Nanni (2002), Pessiki et al. (2001), Prota et al. (2006), Tastani et al. (2006) are included in the database (d).