Issue 37

C. Madrigal et alii, Frattura ed Integrità Strutturale, 37 (2016) 8-14 DOI: 10.3221/IGF-ESIS.37.02

The stress-strain response to the path in Fig. 2 appears in Fig. 3, along with the predicted results. In the calculations reported here only the path sequence in Fig. 2 has been considered. The out-of-phase hardening has been taken into account by obtaining the model parameters, namely the metric constants and the hardening modulus function from the stress response and from the stable effective cyclic stress-strain curve derived in a 90° out-of-phase experiment, respectively.

Figure 3 : Stress response to strain path in Fig. 2.

The model predictions quantitatively agree with the experimental results. The strain and stresses at the end of each path are shown in Tab. 1, along with the model predictions. The model’s average error is around 7,5 %, which is much lower than similar studies reported in the literature [16, 17].

ε

γ

σ (MPa) 0.0

τ (MPa) -94.5

σ (MPa) 0.0

τ (MPa) -98.8

Strain Path

Experimental Results

Model Predictions

Error (MPa)

Error (%)

Error (MPa)

Error (%)

Point

(%)

(%) -1.1

0

0.0

-

0.0

4.3

-4.6

1

0.4

-0.8

80.9

-86.7

77.9

3.0

3.7

-90.5

3.8

-4.4

2

0.5

-0.4

99.7

-80.5

108.5

-8.8

-8.9

-81.9

1.4

-1.7

3

0.6

0.2

142.4

-64.2

152.2

-9.8

-6.9

-60.3

-4.0

6.2

4

0.4

0.9

198.6

-8.8

178.2

20.4

10.3

-7.1

-1.6

18.6

5

0.2

1.1

162.9

44.3

170.7

-7.8

-4.8

49.9

-5.6

-12.6

Table 1 : Comparison of experimental results and model predictions.

A CKNOWLEDGEMENTS

he authors would like to thank the Spanish Ministry of Education for its financial support through grant DPI2014-56904-P. T

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