PSI - Issue 60

M.K. Sahu et al. / Procedia Structural Integrity 60 (2024) 390–401 M. K. Sahu et.al./ Structural Integrity Procedia 00 (2019) 000 – 000

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(a)

(b)

(c)

Fig.2 (a) schematic of test set-up for cyclic tearing tests under four-point bending load and cross sectional view of the through wall crack; (b) loading-scheme for cyclic loading; (c) a typical pipe under cyclic loading arrangement. identical pipe. The ratio, , , ⁄ is also called load reduction factor, which is premediated and in the range of 0.67 to 0.8 in the present investigation. This can be written mathematically as, β= , , (1) In above expression, it is presumed that both pipes tested under cyclic tearing test and related monotonic fracture test are identical in every aspect, i. e. geometry, material and loading configuration. Only difference is that one is loaded monotonically while another is subjected to cyclic loadings. However, there may be minor variation in diameter, thickness and especially crack sizes due to fatigue pre-cracking. Hence the capacity load , obtained by monotonic fracture test should be corrected for any geometrical difference from cyclically tested pipe, if there is any. Hence, both capacity loads of 8-inch and 12-inch pipes , values which are already obtained by