PSI - Issue 64

Davide Santinon et al. / Procedia Structural Integrity 64 (2024) 1095–1102 Jaime Hernan Gonzalez-Libreros / Structural Integrity Procedia 00 (2019) 000 – 000

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Keyword

Occurrence

Mechanical properties

101

Debonding Concrete

88 85 84 78 70 65 61 56 55

Finite element analysis

Adhesion

Strengthening

Interface

Bond

Fracture mechanics Digital image correlation

a)

b)

Fig. 1 a) A uthor’s keywords in the Scopus database; b) First 10 keywords with the highest co – occurrences number

In the numerical field the primary focus is on providing numerical models to simulate the behavior of materials and interfaces in the stress transfer zone, while the experimental field provides experimental results necessary for calibrating the numerical models. There is particular emphasis on instrumentation in the experimental field, as evidenced by the frequent occurrence of the terms "digital image correlation" or "DIC," which are preferred methods for instrumenting the specimens (as they are non-invasive, as explained later in section 3.2), although they cannot provide the exact type of measurement needed to calibrate the numerical model (Tekieli, et al., 2017).

3. Traditional monitoring methods 3.1. Strain gauges (SG)

Strain Gauges (SG) are sensors used to measure the strain in a material, and consequently, deriving its stress state. They consist of thin metallic wires or strips of conductive material (nickel-chromium or nickel-copper alloy) mounted on a flexible base or adhesive backing. When the material on which they are mounted is subjected to mechanical stress, such as tension, compression, or torsion, the electrical resistance of the gauge changes in proportion to the material's strain. Strain gauges are used in a wide range of strain measurement applications, such as structural testing (to monitor deformation in bridges, buildings, airplane wings, laboratory experimental tests, etc.), pressure measurement (applied to devices like piezoresistive pressure sensors to measure pressure in different environments) and measuring the force applied to various mechanical components or devices, industrial applications (to monitor stress or deformation in machinery, pipelines, etc.). They are generally very versatile instruments as they can assume various sizes and configurations depending on the case at hand (Fig. 2).