A New Stress Monitoring Method for Mechanical State of Buried Steel Pipelines under Geological Hazards

Table 3

Comparison of results between stress algorithm and FEM in pipe section 1.

No.	Combination modes			Maximum axial stress (MPa)			Minimum axial stress (MPa)			Maximum shear stress (MPa)
				Algorithm	FEM	Relative error	Algorithm	FEM	Relative error	Algorithm	FEM	Relative error
1	S1	S2	S3	393.71	423.05	−6.93%	−245.18	−232.48	−5.46%	497.55	484.85	2.62%
2	S1	S2	S4	394.74	423.05	−6.69%	−284.02	−232.48	−22.17%	536.39	484.85	10.63%
3	S1	S2	S5	391.94	423.05	−7.35%	−170.02	−232.48	26.87%	422.39	484.85	−12.88%
4	S1	S3	S4	398.27	423.05	−5.86%	−303.21	−232.48	−30.42%	555.58	484.85	14.59%
5	S1	S3	S5	390.10	423.05	−7.79%	−168.17	−232.48	27.66%	420.55	484.85	−13.26%
6	S1	S4	S5	400.07	423.05	−5.43%	−178.15	−232.48	23.37%	430.52	484.85	−11.21%
7	S2	S3	S4	376.44	423.05	−11.02%	−319.19	−232.48	−37.30%	571.56	484.85	17.88%
8	S2	S3	S5	420.19	423.05	−0.68%	−167.86	−232.48	27.79%	420.24	484.85	−13.33%
9	S2	S4	S5	515.46	423.05	21.84%	−182.34	−232.48	21.57%	515.46	484.85	6.31%
10	S3	S4	S5	718.14	423.05	69.75%	−189.94	−232.48	18.30%	718.14	484.85	48.11%