An Artificial Neural Networks model for the prediction of the compressive strength of FRP-confined concrete circular columns

Abstract Nowadays, Fiber Reinforced Polymers are extensively applied in the field of civil engineering due to their advantageous proprieties such as high strength-to-weight ratio and high corrosion resistance in aggressive environments. It is well-known that the compressive strength of concrete significantly increases if a lateral confining pressure is provided. The present paper aims to present an analytical model, able to predict the strength of FRP-confined concrete, which is based on Artificial Neural Networks . The innovation of the proposed model consists of a formulation of an analytical relationship that does not consider the traditional effectiveness parameter commonly found in the models presented in the literature. An extensive experimental database was used to define the variables of the proposed equations. The proposed model is recommended for circular columns with continuous FRP wrapping. The validity of the predictions is indicated through a parametric study and the accuracy is tested by an experimental versus theoretical comparison. An additional comparison is shown by considering the theoretical predictions obtained from the proposed model and the outcomes of equations adopted by important international design codes. The results evidence that the proposed model is adapt for the design of FRP-confined concrete and guarantees an improved accuracy with respect the available competitors.

[1]  H. Toutanji.  STRESS-STRAIN CHARACTERISTICS OF CONCRETE COLUMNS EXTERNALLY CONFINED WITH ADVANCED FIBER COMPOSITE SHEETS , 1999 .

[2]  Ashraf F. Ashour,et al.  Prediction of shear capacity of single anchors located near a concrete edge using neural networks , 2005 .

[3]  H. Toutanji,et al.  BEHAVIOR OF CONCRETE COLUMNS CONFINED WITH FIBER REINFORCED POLYMER TUBES , 1999 .

[4]  Hosein Naderpour,et al.  Prediction of FRP-confined compressive strength of concrete using artificial neural networks , 2010 .

[5]  M. Feng,et al.  Stress-strain model for concrete confined by FRP composites , 2007 .

[6]  Huei-Jeng Lin,et al.  Strength of Concrete Cylinder Confined by Composite Materials , 2001 .

[7]  V. Karbhari,et al.  COMPOSITE JACKETED CONCRETE UNDER UNIAXIAL COMPRESSION--VERIFICATION OF SIMPLE DESIGN EQUATIONS , 1997 .

[8]  Joaquim Agostinho Barbosa Tinoco,et al.  Application of data mining techniques in the estimation of the uniaxial compressive strength of jet grouting columns over time , 2011 .

[9]  T. Kaku,et al.  EVALUATION OF CONFINING EFFECTS OF CFRP SHEETS ON REINFORCED CONCRETE MEMBERS , 1998 .

[10]  M Saiid Saiidi,et al.  SIMPLE CARBON-FIBER-REINFORCED-PLASTIC-CONFINED CONCRETE MODEL FOR MOMENT-CURVATURE ANALYSIS , 2005 .

[11]  Chris P. Pantelides,et al.  Variable strain ductility ratio for fiber-reinforced polymer-confined concrete , 2002 .

[12]  Han-Liang Wu,et al.  Experimental study on reinforced high-strength concrete short columns confined with AFRP sheets , 2010 .

[13]  Mohamed F. M. Fahmy,et al.  Evaluating and proposing models of circular concrete columns confined with different FRP composites , 2010 .

[14]  I. Shehata,et al.  Strength of short concrete columns confined with CFRP sheets , 2002 .

[15]  R. Realfonzo,et al.  Concrete confined by FRP systems: Confinement efficiency and design strength models , 2011 .

[16]  R. Tepfers,et al.  Behavior of concrete cylinders confined by carbon composite 2. Prediction of strength , 2006 .

[17]  Riad Benzaid,et al.  FRP-confined Concrete Cylinders: Axial Compression Experiments and Strength Model , 2010 .

[18]  J. Teng,et al.  Strength Models for Fiber-Reinforced Plastic-Confined Concrete , 2002 .

[19]  C K Jolly,et al.  AN INNOVATIVE FORM OF REINFORCEMENT FOR CONCRETE COLUMNS USING ADVANCED COMPOSITES , 2000 .

[20]  Yufei Wu,et al.  Unified Strength Model for Square and Circular Concrete Columns Confined by External Jacket , 2009 .

[21]  M. Aiello,et al.  Structural Upgrading of Masonry Columns by Using Composite Reinforcements , 2007 .

[22]  A. Ilki,et al.  Low strength concrete members externally confined with FRP sheets , 2004 .

[23]  J. Teng,et al.  Design-oriented stress–strain model for FRP-confined concrete , 2003 .

[24]  P. Hamelin,et al.  Compressive behavior of concrete externally confined by composite jackets , 2006 .

[25]  Amir Mirmiran,et al.  COMPOSITE FRP-CONCRETE COLUMN WITH BI-DIRECTIONAL EXTERNAL REINFORCEMENT , 1996 .

[26]  Soon-Jong Yoon,et al.  Experimental investigation on the structural behavior of concrete filled FRP tubes with/without steel Re-bar , 2011 .

[27]  R. S. Olivito,et al.  La qualificazione dell’esecuzione degli interventi di rinforzo strutturale con FRP a margine delle recenti Istruzioni per la Progettazione, l’Esecuzione ed il Controllo di Interventi di Consolidamento Statico mediante l’utilizzo di Compositi Fibrorinforzati (CNR-DT 200/2004) , 2005 .

[28]  Radhouane Masmoudi,et al.  Axial Load Capacity of Concrete-Filled FRP Tube Columns: Experimental versus Theoretical Predictions , 2010 .

[29]  Amir Mirmiran,et al.  Model of Concrete Confined by Fiber Composites , 1998 .

[30]  Stephanie L. Walkup,et al.  Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures (ACI 440.2R-02) , 2005 .

[31]  Baris Binici,et al.  Design of FRPs in circular bridge column retrofits for ductility enhancement , 2008 .

[32]  J. Mander,et al.  Theoretical stress strain model for confined concrete , 1988 .

[33]  Liu Yu,et al.  Experimental and Computational Studies on High-Strength Concrete Circular Columns Confined by Aramid Fiber-Reinforced Polymer Sheets , 2009 .

[34]  H. Toutanji,et al.  Axial load behavior of large-scale columns confined with fiber-reinforced polymer composites , 2005 .

[35]  Michèle Thériault,et al.  Design equations for axially loaded reinforced concrete columns strengthened with fibre reinforced polymer wraps , 2000 .

[36]  M. R. Spoelstra,et al.  FRP-Confined Concrete Model , 2001 .

[37]  R. Moeini,et al.  Prediction of shear strength of reinforced concrete beams using adaptive neuro-fuzzy inference system and artificial neural network , 2012 .

[38]  Zhishen Wu,et al.  Strength and ductility of concrete cylinders confined with FRP composites , 2006 .

[39]  F. E. Richart,et al.  Failure of plain and spirally reinforced concrete in compression , 1929 .

[40]  Francesco Micelli,et al.  Analytical model based on artificial neural network for masonry shear walls strengthened with FRM systems , 2016 .

[41]  Mark F. Green,et al.  COMPARISON OF CONFINEMENT MODELS FOR FIBER-REINFORCED POLYMER-WRAPPED CONCRETE , 2005 .

[42]  Salim T. Yousif,et al.  NEW MODEL OF CFRP-CONFINED CIRCULAR CONCRETE COLUMNS: ANN APPROACH , 2013 .

[43]  Sidney A. Guralnick,et al.  Strengthening of Reinforced Concrete Bridge Columns with FRP Wrap , 2006 .

[44]  Arnaud Castel,et al.  Artificial neural network model for steel–concrete bond prediction , 2009 .

[45]  Francesco Micelli,et al.  Unified model for hollow columns externally confined by FRP , 2016 .

[46]  E. Vintzileou,et al.  An empirical model for predicting the mechanical properties of FRP-confined concrete , 2008 .