PSI - Issue 67

Oscar Aurelio Mendoza Reales et al. / Procedia Structural Integrity 67 (2025) 8–16 Mendoza Reales et.al. / Structural Integrity Procedia 00 (2024) 000 – 000

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(a) SSCC1

(b) SSCC1

(c) SSCC2 (d) SSCC2 Fig. 5. Stress versus strain curves for SSCC1 (a) and SSCC2 (c), and FCR versus strain curves for SSCC1 (b) and SSCC2 (d). 4. Discussion The effect of temperature over the SSCC presented in Fig. 4 can be considered valid only for a SSCC without any restrictions of movement that allows it to freely expand when temperature increases. In many cases, if a SSCC is ment to work as an embedded sensor, this freedom to expand with temperature would be partially or fully restricted, such as in the case of SSCC embedded in pillars and dams. Thus, it becomes interesting to estimate what the effect of temperature over FCR would be when a SSCC has its freedom of movement fully restricted. It is expected that the thermal expansion of the SSCC causes an increase in the distance between the measuring copper electrodes, which in turn, would increase the electrical resistivity the material. This implies that the measured FCR versus temperature curves are composed of two superimposed physical effects: (i) FCR becoming more positive with temperature due to expansion of the SSCC, and (ii) FCR becoming more negative with temperature due to the increase in electrical conductivity of the composite. This superimposition is represented in equation 4. = + ℎ (4) It is possible to attempt a decoupling of the superimposed phenomena with the experimental information gathered in this work and thus, estimate the effect of temperature when the SSCC are exposed to temperature rises with no freedom for deformation. To perform de above-described decoupling, it would be necessary to assume that the GF obtained from fitting equation 3 to compression experiments, is valid both in compression and tension, which is a fair assumption given the low amounts of strain imposed on the SSCC. Additionally, it would be necessary to assume that