Analysis-oriented stress–strain models for FRP–confined concrete

Abstract

Many stress-strain models have been developed for fibre-reinforced polymer (FRP)-confined concrete. These models fall into two categories: (a) design-oriented models in simple closed-form expressions for direct use in design; and (b) analysis-oriented models in which the stress-strain curve is generated via an incremental process. This paper is concerned with analysis-oriented models, and in particular, those models based on the commonly accepted approach in which a model for actively-confined concrete is used as the base model. The paper first provides a critical review and assessment of existing analysis-oriented models for FRP-confined concrete. For this assessment, a database of 48 recent tests conducted by the authors' group is presented; this database includes 23 new tests which have not previously been published. This assessment clarifies how each of the key elements forming such a model affects its accuracy and identifies a recent model proposed by the authors' group as being the most accurate. The paper then presents a refined version of this model, which provides more accurate predictions of the stress-strain behaviour, particularly for weakly-confined concrete.

Behavior and Design of Slender FRP-Confined Circular RC Columns

“…more than tripled) provided the FRP confinement is strong enough (e.g. Jiang and Teng 2007). The failure of stronglyconfined circular concrete specimens can, however, be explosive and is undesirable in practice.…”

Axial compressive behavior of FRP-confined concrete: Experimental test database and a new design-oriented model

“…Only a small number of studies [10,26,27] reported the FRP properties obtained from ringsplitting tests, and the majority of the studies provided the properties obtained from flat coupon tests or supplied by manufacturers. As for the FRP properties obtained from flat coupon tests, in some of the studies [18,[28][29][30][31][32][33][34][35][36] the elastic moduli (E frp ) and tensile stresses (f frp ) were calculated based on nominal fiber thickness instead of the measured thickness of flat FRP coupons. The datasets from these studies are marked with the superscript 't' in Tables 3 to 7.…”

“…Average hoop rupture strain reduction factor (k ε ) with FRP type and confinement technique Table 4. Lam and Teng [3] Wu and Zhou [52] Wu and Wang [51] Al-Salloum and Siddiqui [45] Wei and Wu [50] Realfonzo and Napoli [7] Bisby et al [5] Jiang and Teng [32] AAE in predictions of strength enhancement ratio (f' cc /f' co ) Wei and Wu [50] Binici [46] Jiang and Teng [42] Youssef et al [53] Teng et al [49] Fahmy and Wu [47] Teng et al [48] De Lorenzis and Tepfers [4] AAE in predictions of strain enhancement ratio (ε cu /ε co ) …”

Investigation of the behavior of carbon fiber reinforced polymer confined standard cylinder concrete specimens under axial load

“…Şekil 10(a)'da verilen eğrilere bakıldığında; tek kat CFRP sargılı durumda, C1-I numunesinden elde edilen deneysel (σ − ε) eğrisinin, Jiang ve Teng [10] tarafından önerilen sargılı beton (σ − ε) davranışını ifade eden modelden elde edilen eğriye çok daha yakın olduğu görülmektedir.…”