Issue 52

S. Budhe et alii, Frattura ed Integrità Strutturale, 52 (2020) 137-147; DOI: 10.3221/IGF-ESIS.52.12 141 Tab. 2 summarizes the test results of 35 burst tests data using pipe specimens with machined different artificial metal losses (defects) [11, 19, 20, 24, 30-33] to demonstrate the suitability of the semi-empirical model for a better prediction of the strength capacity of defect pipe. Sr. No (Ref.) Material Grade y  (MPa) ult  (MPa) D (mm) t (mm) d (mm) L (mm) exp max P (MPa) 1 [19] X80 589 731 459 7.9 3 40 24.2 2 [19] X80 601 684 457 7.9 4 40 22.7 3 [19] X60 452 542 324 9.5 6.67 256 14.4 4 [19] X46 391 458 76.2 2.04 1.4 75 9.4 5 [19] A25 260 309 76.2 2 1.4 75 5.45 6 [19] X60 452 542 324 9.5 6.67 306 14.07 7 [19] X60 452 542 324 9.5 6.67 350 13.58 8 [19] X60 452 542 324 9.5 6.67 395 12.84 9 [19] X60 452 542 324 9.5 6.67 433 12.13 10 [19] X60 452 542 324 9.5 6.67 467 11.92 11 [19] X60 452 542 324 9.5 6.67 484 11.91 12 [19] X60 452 542 324 9.5 6.67 500 11.99 13 [19] X60 452 542 324 9.5 6.67 528 11.3 14 [30] X80 601 684 458.8 8.1 5.39 39.6 22.68 15 [30] X80 589 731 459.4 8.1 3.75 40.05 24.2 16 [20] X42 380 528.5 273.8 5.30 2.52 1000 15.53 17 [20] X42 380 528.5 273.7 5.24 2.04 1000 15.34 18 [20] X46 357.9 458.2 456.5 6.56 3.32 2750 10.34 19 [20] X46 355.7 539.2 457.7 6.23 3.27 2750 12.06 20 [20] X46 362.3 557.3 457.1 6.09 2.8 2750 12.63 21 [20] X46 285.1 428.5 457.7 6.04 2.71 2750 10.13 22 [20] X46 345.4 568.2 457.7 6.03 2.79 2750 13.04 23 [31] X65 495 565 762.0 17.50 8.75 50 27.50 24 [31] X65 495 565 762.0 17.50 8.75 100 24.30 25 [31] X65 495 565 762.0 17.50 8.75 200 21.80 26 [31] X65 495 565 762.0 17.50 8.75 300 19.80 27 [31] X65 495 565 762.0 17.50 8.75 600 18.50 28 [31] X65 495 565 762.0 17.50 8.75 900 15.00 29 [32] X70 532.2 628.8 762 15.9 7.95 300 21.2 30 [33] Steel 20 305 585 219 6 3.6 133 13.8 31 [11] X60 478 542 527 14.3 10 500 11.6 32 [24] X42 284 464 60 5.80 4.1 49.7 54 33 [24] X42 284 464 60 5.60 3.5 49.8 61 34 [24] X42 284 464 60 5.55 4 69.7 46 35 [24] X42 284 464 60 5.62 4.5 50 44 Table 2: Burst tests data B URST PRESSURE PREDICTION USING SEMI - EMPIRICAL MODELS igs. 2 and 3 present the ratio between the predicted burst pressure and the experimental burst pressure (P theoretical /P experimental ) using the different semi-empirical models. The results shows a mixed trend (conservative/non conservative/accurate) of burst pressure values between predicted and experimental with respect to the different semi empirical models. Some models show conservative predictions of burst pressure, while others F