Hollow-Core FRP–Concrete–Steel Bridge Columns under Torsional Loading

This paper presents the behavior of hollow-core fiber-reinforced polymer–concrete–steel (HC-FCS) columns under cyclic torsional loading combined with constant axial load. The HC-FCS consists of an outer fiber-reinforced polymer (FRP) tube and an inner steel tube, with a concrete shell sandwiched between the two tubes. The FRP tube was stopped at the surface of the footing, and provided confinement to the concrete shell from the outer direction. The steel tube was embedded into the footing to a length of 1.8 times the diameter of the steel tube. The longitudinal and transversal reinforcements of the column were provided by the steel tube only. A large-scale HC-FCS column with a diameter of 24 in. (610 mm) and applied load height of 96 in. (2438 mm) with an aspect ratio of four was investigated during this study. The study revealed that the torsional behavior of the HC-FCS column mainly depended on the stiffness of the steel tube and the interactions among the column components (concrete shell, steel tube, and FRP tube). A brief comparison of torsional behavior was made between the conventional reinforced concrete columns and the HC-FCS column. The comparison illustrated that both column types showed high initial stiffness under torsional loading. However, the HC-FCS column maintained the torsion strength until a high twist angle, while the conventional reinforced concrete column did not.

[1]  A. Mirmiran,et al.  A new concrete-filled hollow FRP composite column , 1996 .

[2]  Tao Yu,et al.  Flexural Behavior of Hybrid FRP-Concrete-Steel Double-Skin Tubular Members , 2006 .

[3]  Mohamed A. ElGawady,et al.  Seismic Behavior of Hollow-Core FRP-Concrete-Steel Bridge Columns , 2015 .

[4]  Tao Yu,et al.  Hybrid FRP-concrete-steel tubular columns : concept and behavior , 2007 .

[5]  P. Montague The Experimental Behaviour of Double-Skinned, Composite, Circular Cylindrical Shells under External Pressure: , 1978 .

[6]  T. Rousakis Reusable and recyclable nonbonded composite tapes and ropes for concrete columns confinement , 2016 .

[7]  Mohamed A. ElGawady,et al.  Behavior of Hollow-Core Steel-Concrete-Steel Columns Subjected to Torsion Loading , 2016 .

[8]  X. Zhao,et al.  Investigation on concrete filled double skin steel tubes (CFDSTs) under pure torsion , 2013 .

[9]  Togay Ozbakkaloglu,et al.  Behavior of FRP-Confined Normal- and High-Strength Concrete under Cyclic Axial Compression , 2012 .

[10]  Lin-Hai Han,et al.  Performance of concrete-filled thin-walled steel tubes under pure torsion , 2007 .

[11]  Theodoros C. Rousakis,et al.  Hybrid Confinement of Concrete by Fiber-Reinforced Polymer Sheets and Fiber Ropes under Cyclic Axial Compressive Loading , 2013 .

[12]  Jin-Guang Teng,et al.  Behavior of Hybrid FRP-Concrete-Steel Double-Skin Tubular Columns Subjected to Eccentric Compression , 2010 .

[13]  Haitham Dawood,et al.  Factors affecting the seismic behavior of segmental precast bridge columns , 2014 .

[14]  Mohamed A. ElGawady,et al.  Behavior of hollow FRP–concrete–steel columns under static cyclic axial compressive loading , 2016 .

[15]  Togay Ozbakkaloglu,et al.  Axial Compressive Behavior of Square and Rectangular High-Strength Concrete-Filled FRP Tubes , 2013 .

[16]  Mohamed A. ElGawady,et al.  Strain Rate Effect on Properties of Rubberized Concrete Confined with Glass Fiber–Reinforced Polymers , 2016 .

[17]  Jin-Guang Teng,et al.  ULTIMATE CONDITION OF FIBER REINFORCED POLYMER-CONFINED CONCRETE , 2004 .

[18]  Mohamed A. ElGawady,et al.  Analytical and Finite-Element Modeling of FRP-Concrete-Steel Double-Skin Tubular Columns , 2015 .

[19]  Amir Mirmiran,et al.  SLENDERNESS LIMIT FOR HYBRID FRP-CONCRETE COLUMNS , 2001 .

[20]  Theodoros C. Rousakis Elastic Fiber Ropes of Ultrahigh-Extension Capacity in Strengthening of Concrete through Confinement , 2014 .

[21]  J. Teng,et al.  Experimental behavior of hybrid FRP-concrete-steel double-skin tubular columns under combined axial compression and cyclic lateral loading , 2015 .

[22]  Mohamed A. ElGawady,et al.  Concrete-Filled-Large Deformable FRP Tubular Columns under Axial Compressive Loading , 2015 .

[23]  Jian-Sheng Fan,et al.  Experimental study on seismic behavior of concrete filled steel tube columns under pure torsion and compression–torsion cyclic load , 2012 .

[24]  Mohamed A. ElGawady,et al.  Static cyclic behaviour of FRP-confined crumb rubber concrete columns , 2016 .

[25]  Mohamed A. ElGawady,et al.  Seismic Performance of Innovative Hollow-Core FRP–Concrete–Steel Bridge Columns , 2017 .

[26]  Osamu Kiyomiya,et al.  FUNDEMENTAL PURE TORSIONAL PROPERTIES OF CONCRETE FILLED CIRCULAR STEEL TUBES , 2003 .

[27]  Mohamed A. ElGawady,et al.  Finite element modelling and dilation of FRP-confined concrete columns , 2014 .

[28]  Tao Yu,et al.  Behavior of FRP-confined concrete in annular section columns , 2008 .

[29]  Mohamed A. ElGawady,et al.  Dynamic and Static Behavior of Hollow-Core FRP-Concrete-Steel and Reinforced Concrete Bridge Columns under Vehicle Collision , 2016, Polymers.

[30]  Theodoros C. Rousakis,et al.  Modeling of passive and active external confinement of RC columns with elastic material , 2015 .