2. Benchmark solution#

2.1. Benchmark results#

2.1.1. ZE200a#

2.1.1.1. Calculation of Sn#

The parameter \(\mathit{Sn}\) represents the amplitude of variation of the linear stress (mean stress \(\pm\) flexural stress) between two moments of the transient in question.

math:

`{S} _ {n} =begin {array} {c} {c} {C} {C} _ {1}frac {R} {e} | {A} - {P} - {B} |+ {C}} {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {2}}frac {R} {I} _ {I}}sqrt {({M}} _ {mathit {xB}})} ^ {2} + {({M}} + {({M} _ {mathit {yA}}} - {M} _ {mathit {yB}})} ^ {2} + {({M}} _ {mathit {zA}} _ {mathit {zB}}})} ^ {2})} ^ {2}) + {({M} _ {M} _ {mathit {zB}})} ^ {2}) + {(M} _ {M} _ {mathit {zB}})} ^ {2}) + {(M} _ {M} _ {mathit {zB}})} ^ {2})} + {{M} _ {{M} _ {m {sigma}} _ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {}}) - {mathrm {sigma}} _ {text {tran}}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}} ^ {text {tran}}}

Without thermal constraints, for situation 1 \({S}_{n}=120\) and for situation 2 \({S}_{n}=60\) (at the origin and at the end).

With thermal constraints, we calculate the maximum amplitudes of thermal stresses linearized at the origin and then at the end.

Situation 1

Instant

Thermal constraints

\({\mathrm{\sigma }}^{\mathit{moyen}}\)

\({\mathrm{\sigma }}^{\mathit{flexion}}\)

\({\mathrm{\sigma }}_{0}^{\mathit{lin}}\)

\({\mathrm{\sigma }}_{L}^{\mathit{lin}}\)

Abscissa

0

1

2

1, 5

90

100

110

100

10

90

110

2, 5

0

100

-90

27.5

-45

72.5

-17.5

3, 5

100

-50

-100

-25

-100

75

-125

4, 5

0

0

0

0

0

0

0

Instant 1

Instant 2

\({\mathit{Sn}}_{0}\)

\({\mathit{Sn}}_{L}\)

1, 5

2, 5

17.5

127.5

1, 5

3, 5

15

235

1, 5

4, 5

90

110

2, 5

3, 5

2.5

107.5

2, 5

4, 5

72.5

17.5

3, 5

4, 5

75

125

For situation 1 with thermal constraints, \({\mathit{Sn}}_{0}=120+90=210\) and \({\mathit{Sn}}_{L}=120+235=355\).

Situation 2

Instant

Thermal constraints

\({\mathrm{\sigma }}^{\mathit{moyen}}\)

\({\mathrm{\sigma }}^{\mathit{flexion}}\)

\({\mathrm{\sigma }}_{0}^{\mathit{lin}}\)

\({\mathrm{\sigma }}_{L}^{\mathit{lin}}\)

Abscissa

0

1

2

1

90

100

90

95

0

95

95

2

0

100

-90

27.5

-45

72.5

-17.5

3

100

-50

-100

-25

-100

75

-125

4

0

0

0

0

0

0

0

Instant 1

Instant 2

\({\mathit{Sn}}_{0}\)

\({\mathit{Sn}}_{L}\)

1

2

22.5

12.5

1

3

20

2 20

1

4

9 5

95

2

3

2.5

107.5

2

4

72.5

17.5

3

4

75

125

For situation 2 with thermal constraints, \({\mathit{Sn}}_{0}=60+95=155\) and \({\mathit{Sn}}_{L}=60+220=280\).

2.1.1.2. Calculation of Sn with earthquake#

We have just added the contribution of the earthquake to the magnitude Sn such that

math:

{S} _ {mathit {nS}} =begin {array} {c} {C} _ {1}frac {R} {e} | {P} _ {A} - {A} - {P} _ {B} | {B} |\ + {B}} |\ + {B}} |\ + {C} _ {B} |\ + {C} _ {B} |\ + {C} _ {2}frac {R} {I}}sqrt {({M}} _ {mathit {xA} _ {mathit {xA}}} - {M} _ {mathit {xB}}}pm 2 {M}}pm 2 {M} _ {mathit {xS}})} ^ {2} + {mathit {yA}} - {mathit {yA}}} - {M}} - {mathit {xA}}}} - {mathit {yA}}}} - {mathit {yA}}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} - {M}}} mathit {zA}} - {M} _ {mathit {zB}}}pm 2 {M}} _ {mathit {zS}})} ^ {2})}\ +Vert {mathrm {sigma}}} _ {mathrm {sigma}}} _ {text {sigma}}} _ {text {sigma}}} _ {text {sigma}}} _ {text {sigma}}} _ {text {sigma}}} _ {mathrm {}}) - {mathrm {sigma}}} _ {mathrm {}}} m {sigma}} _ {text {tran}}} ^ {text {lin}} ^ {text {tran}}} ^ {text {}})Vertend {tran}}} ^ {text {tran}}} ^ {text {tran}} ^ {text {tran}}} ^ {text {}})Greenend {array}

For the situation 1 without constraints in the form of a transitory,

math:

{S} _ {mathit {nS}} =begin {array} {c} {C} _ {1}frac {R} {e} | {P} _ {A} - {A} - {P} _ {B} | {B} |+ {B}} |+ {C}} |+ {C}} | + {C} _ {B} |+ {C}} | + {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {C} _ {B} |+ {M} _ {mathit {xB}}}pm 2 {M} _ {mathit {xS}})} ^ {2})}}end {array}

math:

{mathit {Sn}} _ {S} =1astfrac {mathrm {0.5}} {1} |201-1|+2astfrac {mathrm {0.5}} {1} {1}sqrt {1}sqrt {({(21-1pm 2ast 21)}} ^ {2})} =100+62=162 at the origin and at the end.

For the situation 2without constraints in the form of a transitory,

math:

`{mathit {Sn}} _ {S} =1astfrac {mathrm {0.5}} {1} |0-0|+2astfrac {mathrm {0.5}} {1} {1}sqrt {1}}sqrt {({(1-61pm 2ast 21)} {1} |0-0|+2astfrac {mathrm {0.5}}} {1}} {1}} {1}} {1}} {1}} {1}} {mathrm {0.5}}} {1}} {1}} {1}} {1}} {1}} {1}} {5}} {1}} {1}} {1}} {

2.1.1.3. Fatigue calculation for situations 1 and 2 in the same group#

The calculation is detailed for the combination of situations 1 and 2 only and*originally*.

We are trying to fill in the table of elementary use factors.

We first calculate the quantities by situations and then the combination.

Situation 1

For situation 1, remember that with thermal constraints \({\mathit{Sn}}_{0}=210\) (part 2.1.1). The quantity Sp is calculated at the origin.

math:

{S} _ {p} =begin {array} {c} {c} {K} _ {1} {C} _ {1}frac {R} {e} | {P} _ {A} - {P} - {P} - {P} - {P} _ {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} _ {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {P} - {mathit {xA}} - {M} _ {mathit {xB}})})} ^ {2}} + {({M} _ {mathit {yA}} - {M} _ {mathit {yB}}})})})} ^ {2}})} ^ {2} + {({M}} _ {mathit {zB}}})}) ^ {2})}\ +Vert {mathrm {sigma}}} _ {text {tran}}} ^ {text {}} ({t} _ {1} ^ {text {}}) - {mathrm {sigma}}) - {mathrm {sigma}}}} _ {text {sigma}}} _ {text {}})Greenend {array}

Without thermal constraints, for situation 1 \({S}_{p}^{0}=120\).

With thermal constraints, we calculate the maximum amplitudes of thermal stresses linearized at the origin:

Instant 1

Instant 2

\({\mathit{Sp}}_{0}\)

1, 5

2, 5

90

1, 5

3, 5

10

1, 5

4, 5

90

2, 5

3, 5

100

2, 5

4, 5

0

3, 5

4, 5

100

So for situation 1, we have \({\mathit{Sp}}_{0}=120+100=220\).

So for \(\mathit{Sm}=2000\mathit{MPa}\), we have \(\mathit{Ke}=1\) and \({\mathit{Salt}}_{0}=\frac{1}{2}\frac{{E}_{c}}{E}\mathit{Ke}{\mathit{Sp}}_{0}=110\mathit{MPa}\). According to the Wöhler curve we therefore have \({\mathit{Nadm}}_{0}=\frac{500000}{{\mathit{Salt}}_{0}}=4545\) or \({\mathit{FU}}_{0}=\mathrm{2,2}{10}^{-4}\).

Situation 2

Similarly for situation 2, we have \({\mathit{Sn}}_{0}=155\), \({\mathit{Sp}}_{0}=60+100=160\), or \(\mathit{Ke}=1\) and \({\mathit{Salt}}_{0}=80\mathit{MPa}\) or \({\mathit{FU}}_{0}={\mathrm{1,6.10}}^{-4}\).

Combination of situations 1 and 2

For the combination of situations 1 and 2 we have without the thermal

math:

{S} _ {n} ^ {0} =begin {array} {0} =begin {array} {0} =frac {R} {e} |201-0|+ {C} _ {2}frac {R} {0}}frac {R} {0}} =frac {R} {0} {0}} =frac {R} {0} {0} =frac {R} {0} {0} =frac {R} {0} {0} =frac {R} {0} {0} =frac {R} {0} {0} =frac {R} {0} {0} =frac {R} {0} {0} =frac {R} {0} {mathrm {140.5}

With thermal we have \({\mathit{Sn}}_{0}=95+\mathrm{140,5}=\mathrm{235,5}\) for moments 4,5 and 1. So \(\mathit{Ke}=1\).

Without thermal \({\mathit{Sp}}_{0}^{1}=\mathrm{140,5}\) then for example by combining the moments 2.5 and 3 \({\mathit{Sp}}_{0}^{1}=\mathrm{240,5}\) or \({\mathit{FU}}_{0}^{1}=\mathrm{2,405.}{10}^{-4}\).

We calculate the second fictional transient, without the thermal on the moments and the pressure we take the complementary states either:math: {mathit {Sp}} _ {0} ^ {2} =begin {array} {c} {C} {C} {C} {C} {C} {C} {C} {2} =begin {array} {c} {2} =begin {array} {c} {C} {2} =begin {array} {c} {C} {2} =begin {array} {c} {C} {C} {2} =begin {array} {c} {C} {C} {2} =begin {array} {c} {C} {C} {2} =begin {array} {c} {C} {C} {{(1-1)} ^ {2})}end {array} =mathrm {0.5}. Then by combining the moments 3.5 and 2:math: {mathit {Sp}}} _ {0} ^ {2} =100+mathrm {0.5} =mathrm {100.5} either:math: {mathit {FU}}} _ {0} ^ {2} =mathrm {1,005.} {10} ^ {-4}.

So the use factor of combining situations 1 and 2 is \(\mathit{FU}={\mathit{FU}}_{0}^{1}+{\mathit{FU}}_{0}^{2}=\mathrm{2,405.}{10}^{-4}+\mathrm{1,005.}{10}^{-4}=\mathrm{3,41.}{10}^{-4}\)

So the table of elementary factors of use at the origin is

Situation 1

Situation 2

Situation 1

\(\mathrm{2,2}{10}^{-4}\)

\({\mathrm{3,41.10}}^{-4}\)

Situation 2

\({\mathrm{1,6.10}}^{-4}\)

As we have \({\mathit{Nocc}}_{1}=1\) and \({\mathit{Nocc}}_{2}=1\) we have \({\mathit{FU}}_{\mathit{TOTAL}}^{\mathit{ORI}}={\mathrm{3,41.10}}^{-4}\).

2.1.2. ZE200b#

2.1.2.1. Calculation of Sn#

The parameter \(\mathit{Sn}\) represents the amplitude of variation of the linear stress (mean stress \(\pm\) flexural stress) between two moments of the transient in question.

\({S}_{n}=\begin{array}{c}{C}_{2}\frac{R}{I}\sqrt{({({M}_{\mathit{xA}}-{M}_{\mathit{xB}})}^{2}+{({M}_{\mathit{yA}}-{M}_{\mathit{yB}})}^{2}+{({M}_{\mathit{zA}}-{M}_{\mathit{zB}})}^{2})}+\Vert {\mathrm{\sigma }}_{\text{tran}}^{\text{lin}}({t}_{1}^{\text{}})-{\mathrm{\sigma }}_{\text{tran}}^{\text{lin}}({t}_{2}^{\text{}})\Vert \end{array}\)

Without thermal constraints or pressure, for situation 1 \({S}_{n}=20\) (at the origin and at the end).

With stresses in the form of a transient, we calculate the maximum amplitudes of thermal stress+pressure linearized at the origin and then at the end.

Situation 1

Instant

Thermal stress+pressure

\({\mathrm{\sigma }}^{\mathit{moyen}}\)

\({\mathrm{\sigma }}^{\mathit{flexion}}\)

\({\mathrm{\sigma }}_{0}^{\mathit{lin}}\)

\({\mathrm{\sigma }}_{L}^{\mathit{lin}}\)

Abscissa

0

1

2

1, 5

180

200

220

200

20

180

220

2, 5

0

200

-180

55

-90

145

-35

3.5

200

-100

-200

-50

-200

150

-250

4, 5

0

0

0

0

0

0

0

Instant 1

Instant 2

\({\mathit{Sn}}_{0}\)

\({\mathit{Sn}}_{L}\)

1, 5

2, 5

35

255

1, 5

3, 5

30

470

1, 5

4, 5

18 0

220

2, 5

3, 5

5

215

2, 5

4, 5

145

35

3, 5

4, 5

150

250

For situation 1 with constraints in the form of a transitory, \({\mathit{Sn}}_{0}=20+180=200\) and \({\mathit{Sn}}_{L}=20+470=490\).

Situation*2

Without thermal constraints or pressure, for situation 2 \({S}_{n}=60\) (at the origin and at the end).

Situation 2 has no pressure constraints so the calculation of the part in the form of a transient is the same as in ZE200a (part 2.1.1.1).

For situation 2 with thermal constraints, \({\mathit{Sn}}_{0}=60+95=155\) and \({\mathit{Sn}}_{L}=60+220=280\).

2.1.2.2. Calculation of Sn with earthquake#

We have just added the contribution of the earthquake to the magnitude Sn such that

\({S}_{\mathit{nS}}=\begin{array}{c}{C}_{2}\frac{R}{I}\sqrt{({({M}_{\mathit{xA}}-{M}_{\mathit{xB}}\pm 2{M}_{\mathit{xS}})}^{2}+{({M}_{\mathit{yA}}-{M}_{\mathit{yB}}\pm 2{M}_{\mathit{yS}})}^{2}+{({M}_{\mathit{zA}}-{M}_{\mathit{zB}}\pm 2{M}_{\mathit{zS}})}^{2})}\\ +\Vert {\mathrm{\sigma }}_{\text{tran}}^{\text{lin}}({t}_{1}^{\text{}})-{\mathrm{\sigma }}_{\text{tran}}^{\text{lin}}({t}_{2}^{\text{}})\Vert \end{array}\)

For the situation 1 without constraints in the form of a transitory,

\({S}_{\mathit{nS}}=\begin{array}{c}{C}_{2}\frac{R}{I}\sqrt{({({M}_{\mathit{xA}}-{M}_{\mathit{xB}}\pm 2{M}_{\mathit{xS}})}^{2})}\end{array}=2\ast \frac{\mathrm{0,5}}{1}\sqrt{({(21-1\pm 2\ast 21)}^{2})}=62\) at the origin and at the end.

For the situation 2without constraints in the form of a transitory,

\({S}_{\mathit{nS}}=\begin{array}{c}{C}_{2}\frac{R}{I}\sqrt{({({M}_{\mathit{xA}}-{M}_{\mathit{xB}}\pm 2{M}_{\mathit{xS}})}^{2})}\end{array}=2\ast \frac{\mathrm{0,5}}{1}\sqrt{({(1-61\pm 2\ast 21)}^{2})}=102\) at the origin and at the end.

2.2. Uncertainty about the solution#

Analytical solution.