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Nonlinear elastic characterization of concrete materials is a promising approach for actual stress detection in structural elements. In this study we investigate the use of the “torsional nonlinear parameter” βG of elongated concrete specimens to detect the actual uniaxial stress level. We derive a theoretical expression of βG ex-pressed in terms of the third order elastic constants l, m and n. Then we apply quasistatic uniaxial loading cycles on a 15 x 15 x 60 cm3 specimen and measure βG using the torsional resonance technique, obtaining an average βG = -125. This re-sult is compared against the βG measured using ultrasonic wave propagation in the same specimen during the same test. Finally, we measure βG in a real size reinforced concrete column using the torsional resonance technique, obtaining βG =-650. A final discussion is posed to analyze the findings and to guide future research.