PSI - Issue 75

Ralf Glienke et al. / Procedia Structural Integrity 75 (2025) 474–488 Ralf Glienke et al / Structural Integrity Procedia 00 (2019) 000 – 000

478

5

comparison to tests on small-scale specimens with low R-ratios. 3. Experimental work

This paper focuses on the effect of blast-cleaning on the fatigue strength of various constructional details. No general statements are to be made on the re-evaluation of detail categories, but rather on the effect of blast-cleaning on fatigue strength. 3.1. Test program Table 1 shows the test program, which includes fatigue tests on the constructional details of transverse loaded butt welds (BW), thermal cut edges (TCE), base material (BM) with mill scale and flat bars with central hole (FB).

Table 1. Test program on transverse loaded butt welds, thermal cut edges, base material and flat bars with central hole

Constructional detail EN 1993-1-9

Specimen type 1)

Process 2)

Condition 3)

Steel grade

f y,obs [MPa]

f u,obs [MPa]

t [mm]

b [mm]

Hole Ø [mm]

SCF K t [-] 2.38 2.49 2.37 2.66 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0 ~ 1.0

R [-]

No. of tests [-]

Ref.

#

BW BW BW BW BW BW TCE TCE TCE TCE

SAW SAW SAW SAW SAW SAW

aw

01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20

S355J2+N 431

526 526 526 526 544 546 448 448 518 518 421 421 545 545 874 874 421 421 421 421

20 20 20 20 40 40 10 10 10 10 10 10 10 10 10 10 10 10 10 10

40 40 40 40 80 80 25 25 25 25 25 25 25 25 25 25 30 30 95 95

- - - - - - - - - - - - - - - -

0.3 0.3

22 28

Ref. A Ref. B

BC Sa 3 S355J2+N 431 BC Sa 3 S355J2+N 431 BC Sa 3 S355J2+N 431

2.39 0.4 - 0.5 2.34  max = f y 4)

18 5)

- 6) - 6)

24 22 16 19 12 12

DC 90 (m 1 = 3)

aw

S355J2+N 431

0.3 0.3

Ref. A

BC Sa 3 S355J2+N 416

- 6)

L L

ac

S235JR S235JR

321 321

-1.0 -1.0

Ref. C

BC Sa 3

- 6)

OF OF

ac

S355J2+N 365

0.1 0.1

Ref. C Ref. D Ref. E Ref. E Ref. F

DC 125 (m 1 = 3)

BC Sa 3 S355J2+N 365

12 5)

BM BM BM BM BM BM

M M M M M M

MS

S235JR S235JR

294 294

-1.0 -1.0 -1.0 -1.0 -1.0 -1.0

19 16

BC Sa 3

MS

S355J2+N 394

9 4

BC Sa 3 S355J2+N 394

- 6) - 6) - 6)

DC 180 (m 1 = 3)

MS

S690QL S690QL S235JR S235JR S235JR S235JR

821 821 294 294 294 294

13 13 14 14 14

BC Sa 3

FB FB FB FB

D D

MS

10 2.31 10 2.31 24 2.43 24 2.43

0.1 0.1

Ref. E Ref. E Ref. E

BC Sa 3

M M

MS

0.1 4)

DC 90 (m 1 = 3)

BC Sa 3

0.1

5

- 6)

Total number of fatigue tests 306

List of acronyms 1) BW – transverse loaded butt weld in quality level B acc. to ISO 5817 / TCE – thermal cut edges – laser (L) resp. oxy fuel (OF) cutting /

BM – base material / FB - flat bar with central hole 2) SAW – submerged arc welding / L – laser cutting (R

z ~ 35µm) / OF – oxy-fuel cutting (R z ~ 40µm) / M – machined edge / D – drilled hole

3) aw – as welded / BC – blast-cleaned / ac – as-cut / MS – mill scale 4) maximum stress  max = f y with varying R- ratios, but R ≤ 0.5 5) Additional tests on the stability of the introduced compressive residual stresses 6) unpublished investigations Ref. A: Glienke et al. (2024b), Ref. B: Glienke et al. (2024a), Ref. C: Glienke et al. (2024d), Ref. D: Schröder et al. (2025), Ref. E: Glienke et al. (2024c), Ref. F: (Kalkowsky et al. 2024) Table 1 provides the specimen dimensions in the cross-section as well as the observed yield strength f y,obs and ultimate strength f u,obs of the base material. The base materials also fulfil the requirements (chemical composition, elongation after fracture) of the delivery standards (EN 10 025) or EN 1993-1-1 (2025) (f u /f y  1.1 and A  15 %). The test specimens for the butt welds (series #02 to #04 and #06) and the test specimens of the non-welded constructional details were blast-cleaned for surface preparation grade Sa 3.