Issue 35

S. Valente et alii, Frattura ed Integrità Strutturale, 35 (2016) 306-312; DOI: 10.3221/IGF-ESIS.35.35 309 Parameters Unit Rock Concrete MPa 41000 24000 Poisson ratio - 0.10 0.15 Tensile strength MPa 2.6 1.3 Table 2 : Properties of rock and concrete. Crack growth conditions in the closeness of the Fictitious Crack Tip The above mentioned hypotheses are related to a surface: the dam-to-foundation interface. On the contrary, the following hypotheses are related to a volume of dam concrete and a volume of rock foundation. Both domain are meshed by means of triangular elements of constant strain type. As shown in Fig.3, the dam is divided into 2205 elements and the foundation into 5673 elements. In the closeness of the interface, the triangles are assumed as equilateral, with a side of 0.6 m. The four stress components are computed in two elements connected to the joint and to the FCT: one for the dam and another for the foundation. The stress level is compared to the Mohr-Coulomb criterion shown in Fig.4. Figure 3 : Finite element mesh used in the numerical analysis. Figure 4 : Mohr-Coulomb criterion applied at the Fictitious Crack Tip.