Tension stiffening approach for deformation assessment of flexural reinforced concrete members under compressive axial load

• Published in: Structural concrete : journal of the FIB Vol. 20; no. 6; pp. 2056 - 2068
• Main Authors: Ng, Pui‐Lam, Gribniak, Viktor, Jakubovskis, Ronaldas, Rimkus, Arvydas
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY‐VCH Verlag GmbH & Co. KGaA 01.12.2019; Wiley Subscription Services, Inc
• Subjects: Adequacy; axial load; Axial loads; Axial stress; Concrete blocks; Deformation; finite element analysis; Finite element method; flexural member; Reinforced concrete; Stiffening; Stress distribution; Tensile stress; tensile stress block; Tension stiffening
• ISSN: 1464-4177; 1751-7648
• DOI: 10.1002/suco.201800286

The deformation characteristics of cracked reinforced concrete beams are largely dependent on the tension stiffening effect. As one of the serviceability analysis approaches, the employment of a concrete tensile stress block that reflects the flexural tension stiffening behavior is useful for evaluation of beam deflections. In many practical applications, however, beams have to withstand a small degree of axial compression. There has been little research on axial load effects on tension stiffening, and tensile stress block for beams subject to compressive axial load has not been developed. In this study, finite element method is employed to analyze beams under different levels of compressive axial load. The numerical results reveal that the tensile stress block is considerably influenced by the presence of axial load. Using the tension stress fields obtained, values of stress block parameters under different levels of axial load are determined. Adequacy of the proposed model was verified using the test data reported in the literature.