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EN 13001 Fatigue (2018)

EN 13001 Fatigue (2018) – a crane standard EN 13001-3-1+A2 Limits States and proof competence of steel structure.

EN13001 Fatigue (2018)

To add EN 13001 Fatigue (2018) Standard execute Standards - Main - EN 13001 - EN 13001 Fatigue (2018) from the ribbon:

add EN13001 Standard

Press to Set Standard Custom Settings

EN 13001-3-1 standard deals only with the limit state method. The allowable stress method is reliable in specific cases - for cranes where all masses act only unfavorable with a linear relationship between load actions and load effects.

Static Strength

For static strength, the default method is the Limit State Method. If the Allowable Stress design method is used press to specify safety factors for Individual Loads and Load Sets. The limit design stress for normal stresses:

EN13001_limit_design_stress_for normal_stresses_formula

For shear stresses:

EN13001_limit_design_stress_for shear_stresses_formula

Where EN13001_YRm formula

is the general resistance factor (EN13001-2).

is the specific resistance factor for the material.

Press Button_Element_Characteristic to define characteristic with specific resistance factor.

In case of plane states of stresses when von Mises stresses are not used it shall additionally be proven that:

EN13001_Formula24

Fatigue Strength

Fatigue Strength can be calculated using 2 methods: Direct Use of Stress History and Simplified Method (Chapter 6.5.3).

EN13001_fatigue_strength

In the direct use of stress history method Stress History Parameter is calculated automatically based on stress ranges and stress history (Fatigue Group):

Example: Fatigue Group with a total amount of cycles 4 million:

EN13001_fatigue_group_example

Stress History Parameter:

EN13001_stress_history_parameter

ν is the relative total number of occurrences of stress ranges;
kmis the stress spectrum factor dependent on m;
Δ σi is the stress range i;
Δ^σthe maximum stress range;
niis the number of occurrences of stress range i;
EN13001_Nt formula is the total number of occurrences of stress ranges during the design life of the crane;
mis the slope constant of the logΔσ—logN -curve of the component under consideration.

The limit design stress for fatigue

EN13001_limit_design_stress_for_fatigue_formula

ΔσRdis the limit design stress range
Δσc ia the characteristic fatigue strength (see Annex D and Annex H)
mis the slope constant of the ogΔσ—logN curve (see Annex D and Annex H)
ϒmfis the fatigue strength specific resistance factor (see Table 9)
smis the stress history parameter

The combined fatigue effect of normal and shear stresses:

EN13001_combined_effect_of_normal_and_shear_stresses_formula

Note: Maximum value between each combination (x^2 + xy^2 + xz^2, y^2 + xy^2 + yz^2, z^2 + yz^2 + xz^2) will be taken as a result of formula 41.

Check with the simplified method is optional, stress history parameter is user input and fatigue is calculated for one stress range (Load Group) without summation.

For Fatigue strength resistance factor, notch class, slope factor, and reduced stress range have to be defined.

Fatigue strength specific resistance factor is an elemental characteristic. Chapter 6.1 Table 9:

Accessibility for inspection Fail-safe detail Non fail-safe detail
Without hazard for personsb With hazard for persons
Detail accessible without disassembly 1.0 1.05 1.15
Detail accessible by disassembly 1.05 1.10 1.20
Non-accessible detail N/A 1.15 1.25

Notch Class and Slope Factor should be defined for different direction: X - parallel to the weld, Y - perpendicular, XY - Shear based on Annex D.

EN13001_weld_direction_table

Button_define_notch_class - define Notch class.

Example of classification:

EN13001_edit_classification

Button_clear_classification_results - clear classification results.

In non-welded details or stress-relieved welded details the effective stress range may be calculated by adding the tensile portion of the stress range and 60% of the magnitude of the compressive portion of the stress range:

EN13001_effective_stress_range_diagram

By default, the Reduced Range is set to Not Reduced. Press Button_Element_Characteristic to specify the selection which should use reduced stress range:

EN13001_add_element_characteristic

Standard uses material data (Yield/Tensile) in calculations. Wizard checks if the values are defined for all materials.

Use Hot Spot Stress - use Hot Spot Stress results for locations defined in Weld Finder Tool or Weld Stress results in the fatigue checks.

Include Rainflow Counting - include rainflow fatigue summation check with defined result category and method from which Rainflow Counting data will be used.

Note: category options for fatigue are Weld Stress or Hot Spot Stress.

Note: this option is available only for Enterprise licensing.