Prestress state evolution during thermal activation of memory effect in concrete beams strengthened with external SMA wires / A. Debska, Piotr Gwozdziewicz, A. Seruga, X. Balandraud, J. F. Destrebecq // ... więcej

Prestress state evolution during thermal activation of memory effect in concrete beams strengthened with external SMA wires / A. Debska, Piotr Gwozdziewicz, A. Seruga, X. Balandraud, J. F. Destrebecq // Archives of Civil and Mechanical Engineering [Dokument elektroniczny]. – 2020, Vol. 20, Iss. 4, 15 s. : fot., schem., tab., wykr. – Tryb dostępu: https://link.springer.com/article/10.1007%2Fs43452-020-00133-y. – Oznaczenie ref./art.: 142. – Bibliogr. 40 poz., Abstr. – doi: 10.1007/s43452-020-00133-y. – ISSN 1644-9665

The memory efect of shape-memory alloys (SMAs) has opened interesting perspectives to create prestress states in concrete elements. However, the procedure has not been yet fully resolved due to the complex ... więcej

The memory efect of shape-memory alloys (SMAs) has opened interesting perspectives to create prestress states in concrete elements. However, the procedure has not been yet fully resolved due to the complex thermomechanical behavior of these alloys, in addition to the practical difculties of mechanical coupling between SMA and concrete elements. The present study deals with tests on the development of prestressing forces in concrete beams during the thermal cycle required in the procedure. Pre-stretched nickel-titanium wires were externally placed on concrete prismatic beams equipped with strain gauges. As concrete rupture may occur during the heating by the Joule efect, a compromise must be found between the SMA pre-stretch level and the maximum temperature to be applied before returning to ambient temperature. A macroscopic model was developed to analyze this compromise. The complex thermomechanical response of SMAs implies a particular attention in the defnition of the ambient temperature and heating conditions for the creation of prestress states in concrete components.