Issue34

A. Satoh et alii, Frattura ed Integrità Strutturale, 34 (2015) 397-405; DOI: 10.3221/IGF-ESIS.34.44 401 0 1 2 3 4 5 6 0 0.001 0.002 0.003 0.004 0.005 Stress (N/mm 2 ) Deformation (mm) M M-I M-S M-V 0 1 2 3 4 5 6 0 0.001 0.002 0.003 0.004 0.005 Stress (N/mm 2 ) Deformation (mm) R R-I R-S R-V (a) Response of Model M with the properties for mortar. (b) Response of Model R with the properties for repair. Figure 6 : Analyzed stress-deformation response for monolithic models. Fig. 7 represents the crack distribution at the final stage of fracture. Though the final crack path is the straight one in all the cases in Fig. 7, the distribution of cracked element is very wide spread in the case of ductile matrix. Crack distribution of Model R-V is wider than Model R-I and R-S helped with voids, making the response weak and ductile. (a) Model M-I. (b) Model M-S. (c) Model M-V. (d) Model R-I. (e) Model R-S. (f) Model R-V. Figure 7 : Crack distribution in models at the final stage of fracture. A NALYSIS OF MODEL S AND W he authors analyzed Model S and W. The material property of the interface is different with 3 types: TSD1, TSD2 and TSD3, which are depicted in Fig. 8. The tensile strength of interface (LB) in TSD is varied from 6.21 MPa (average of the strength of substrate and repair) through 4.95 MPa (95% of the strength of repair) to 4.278 MPa (82% of the strength of repair). Strength of layer of wall effect (LWE) is the same as repair (5.21 MPa), but more brittle than repair. Type N model has no iron aggregate whereas Type A has iron aggregate as shown in Fig. 4. The response is depicted in Fig. 9. The responses of TSD1 in Fig. 9(a) are almost the same each other, because repair is ductile and the crack path mainly extends in repair (See Fig. 10(a1) to Fig. 10(d1)). Then the effects of high modulus aggregates do not appear in the same way as discussed in the former chapter regarding the strength of Model R. T