Effects of winding and straightening of medium and large diameter reinforcing bars manufactured in coils in their mechanical properties


  • J. M. Bairan Universitat Politècnica de Catalunya (UPC)
  • A. R. Marí Universitat Politècnica de Catalunya (UPC)
  • H. Ortega Compañía Española de Laminación (CELSA)
  • J. C. Rosa Universitat Politècnica de Catalunya (UPC)




Coiled rebars, ductility, residual stresses, mixed-hardening


Reinforcing bars produced in coils offer important logistic and environmental advantages, for this reason there is a tendency to produce them in medium and larger diameters. Fabrication introduces complex load and temperature histories producing residual stresses. This paper presents an experimental and theoretical study of the incidence in the mechanical properties of reinforcing bars manufactured in coils, mainly in terms of ductility. Experimentation included phases of characterization of the core and crown regions of the bar, and comparison of straight bars and identical rolled bars straightened in laboratory conditions. Numerical study is based in a mixed-hardening constitutive model and allows considering the actual geometry of the bar as well as the high temperatures involved. The model identifies the origin and distribution of residual stresses and the main effects in the mechanical properties of the bars. Finally, recommendations are given regarding coil radius in order to control bar ductility.


Download data is not yet available.


(1) AENOR. UNE-EN-ISO 15630-1:2003: “Aceros para el armado y pretensado del hormigón. Método de ensayo. Parte 1: Barras, alambres y alambrón para el hormigón armado” (2003).

(2) Comisión Permanente del Hormigón: “Instrucción de Hormigón Estructural. EHE-08”, Ministerio de Fomento (2008), pp. 722.

(3) Bontcheva, N.; Petzov, G.: “Total simulation model of the thermo-mechanical process in shape rolling of steel rods”, Computational Materials Science, vol. 34 (2005), pp. 377-388. http://dx.doi.org/10.1016/j.commatsci.2005.01.009

(4) Yong-Soon, J. D. C.; Byung-Min, K.: “Application of the finite element method to predict microstructure evolution in the hot forging of steel”, Journal of Materials Processing Technology, vol. 101 (2000).

(5) Nikolau, J.; Papadimitriou, G.: “Microstructures and mechanical properties after heating of reinforcing 500 MPa class weldable steels produced by various processes”, Construction and Building Materials, vol. 18 (2004), pp. 243-254. http://dx.doi.org/10.1016/j.conbuildmat.2004.01.001

(6) Zheng, H.; Abel, A.: “Fatigue properties of reinforcing steel produced by TEMPCORE Process”, Journal of Materials in Civil Engineering, 11 (2) (1999), pp. 158-165. http://dx.doi.org/10.1061/(ASCE)0899-1561(1999)11:2(158)

(7) National Institute of Standards and Technology (NIST): “Mechanical properties of structural steels”. NIST NCSTAR 1-3D, Department of Commerce, USA (2005), pp. 288.

(8) Comité Européen de Normalisation (CEN): “Eurocode 3: Design of steel structures. Part 1.2: General rules – Structural fire design”. Comité Européen de Normalisation, prEN 1993-1-2:02/2002 (2002).

(9) Marí, A. R.; Bairán, J. M.: “Evaluación de los efectos estructurales del deterioro, reparación y refuerzo, mediante análisis no lineal evolutivo”. Hormigón y Acero, vol. 60, nº 254 (2009), pp. 51-63.

(10) Marí, A. R.: “Nonlinear geometric, material and time dependent analysis of three dimensional reinforced and prestressed concrete frames”, Report No. USB/SESM-84/12. U.C. Berkeley, Berkeley, June, 1984.




How to Cite

Bairan, J. M., Marí, A. R., Ortega, H., & Rosa, J. C. (2011). Effects of winding and straightening of medium and large diameter reinforcing bars manufactured in coils in their mechanical properties. Materiales De Construcción, 61(304), 559–581. https://doi.org/10.3989/mc.2011.60110



Research Articles