PSI- Issue 9

Ch.F. Markides et al. / Procedia Structural Integrity 9 (2018) 108–115 Author name / Structural Integrity Procedia 00 (2018) 000–000

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Taking advantage of Eqs.(17) and (19), as well as of the experimental data provided by the DIC system, Fig.4 is drawn. In this figure the analytically determined horizontal displacement component u x , developed along the locus AB (shown in the sketch embedded), is plotted, in juxtaposition to the respective experimentally measured quantity. Excluding a qualitative difference, related to the position of the maximum value of the distribution (which according to the analytic solution is located exactly at point B while according to the experimental data it is located at some distance from point B), the two curves (analytic and experimental) are in relatively good agreement to each other.

1.20

1.15

B A

1.10

u x [mm]

1.05

Analytic solution Experimental data

1.00

0.95

25

30

35

40

45

50

r [mm]

Fig. 4. Experimentally determined displacements u x vs. the analytic ones.

4. Discussion and conclusions Concerning the stress field, the most crucial feature of the CSR test is the stress developed along x-axis, given that for a successful test fracture is expected along the specific locus. Therefore, in case the CSR test is to be used for the determination of the material’s tensile strength, what is of importance is the maximum transverse normal stress, σ θ , developed along x-axis. The specific stress component, for the CSR under compression and bending, is plotted in Fig.5 (for the same as previously numerical data), along the locus of interest (denoted as AB in the sketch embedded in Fig.5) (Markides and Kourkoulis (2018)). As expected, σ θ is compressive at the inner part of AB (25mm

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    

 2 2 2 2c R R 2R og(R R ) R R 4R R og(R R )          2 1 1 2 1 2 2 2 2 1 2 1 2 1  2 2 

2 2 R R 

2

P h

   

(21)



1





2 R R R (R R ) og(R R )     2

 

2 2

2 2

2





2 1

1

2 1