Issue 48

Y.H. Shao et alii, Frattura ed Integrità Strutturale, 48 (2019) 757-767; DOI: 10.3221/IGF-ESIS.48.69

110

120

计算应力 实测应力

当量垂向载荷计算应力 实测应力

100

80

80

50

60

20

40

应力 /Mpa

-10

20

-40

0

-20 Stress /MPa 应力（Mpa）

Stress / P

-70

-40

-100

350

400

450

500

790

810

830

850

870

890

910

采样时刻（s） Sampling time / s

采 样时刻 (s) Sampling time / s

(b) No.2 measuring point on bucket rod

(a) No.1 measuring point on moving arm

Figure 3 : Comparisons of calculated stress and measured stress at measuring points

Fatigue crack

(i)

(ii) Enlarged view

(a) Fatigue failures on moving arm

Fatigue crack

(i)

(ii) Enlarged view

(b) Fatigue failures on bucket rod

Figure 4 : Fatigue failures on No.1 excavator

Fatigue crack

Figure 5 : Fatigue failures on moving arm of No.2 excavator, which is the same as failure position of No.1 excavator

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