PSI - Issue 47

Caroline Bremm et al. / Procedia Structural Integrity 47 (2023) 261–267 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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For the Frictionless conditions, the slenderness does not influence the results, with an average axial compression strength of 57 MPa. For the Fixed condition, the slenderness has a significant influence, with the average axial compression strength decreasing with the increase in slenderness level. This can be explained by the action of triaxial stresses generated when horizontal displacements are restricted. These stresses have a greater influence on samples with lower slenderness. On the other hand, when the slenderness increases, triaxial stresses have less influence on the sample behavior. Both conditions, Frictionless and Fixed, have quite similar average axial compressive strength values.

Fig. 3. Average axial compressive strength against slenderness level of concrete by considering the Model A and the Model B for different boundary conditions.

Fig. 4 shows the influence of the cross-section shape of the sample, that is, square and circular, by considering h/b=2.0, on the axial compressive strength of the concrete for both models. It can be observed that the cross-section shape influences the compressive strength independently of the model applied. More precisely:  For the Frictionless condition and a square cross-section, an average axial compressive strength equal to about 56 MPa is obtained, by considering both the Model A and the Model B, whereas, for the circular one, such a value is equal to about 21 MPa.  For the Fixed condition and a square cross-section, an average axial compressive strength equal to about 64 MPa is obtained, by considering both the Model A and the Model B, whereas for the circular one, such a value is equal to about 31 MPa.