This tab extends the Design tab. You can calculate bolted connection data based on selections in the Design tab.
|
Access: |
Ribbon: Design tab  Fasten panel Bolted Connection  and then click the Fatigue Calculation tab.
|
Loads
Select the type of loading.
Calculation Parameters
This area displays calculated forces and stresses in the bolt and pressure in the nut thread.
|
Dynamic Stroke Factor |
It is necessary to include the Dynamic Stroke Factor in the calculation if strokes actuate on the joint. In this case the Dynamic Stroke Factor is used. The button located beside the edit field opens a Recommended value of dynamic stroke factor dialog box, where you can select a coefficient value. |
|
Life of a Joint in Thousands Deflections |
Select one of the preset values. |
|
Required Safety Degree |
Required Safety Degree of the bolted connection during fatigue loading is the ratio of fatigue strength and the calculated stress of the bolted connection. The dialog box enables its selection. It is displayed after you click the button beside the edit field. |
|
Strength Ratios |
See the Bolted Connection Endurance Limit Determination chapter in the Engineer's Handbook for used calculation. |
Fatigue Strength Calculation method
Use the pull-down menu to select a method that defines the fatigue curve for determining of the fatigue strength of the bolted connection. The used fatigue curve is displayed in this area.
|
Factor of Haigh diagram Narrowing |
Depends on the joint material (recommended values) for traction and bending Ψ <0.15...0.3>. |
Endurance Limit Calculation Parameters
|
Basic Endurance Limit Material |
Basic endurance limit of a test bar from the selected material. This value is automatically inserted by the calculation. To change the value manually, clear the box. |
|
Modifying Factor of Stress Concentration |
Modified factor of stress concentration is determined from the k e = 1/K formula, where the fatigue-strength reduction factor K depends on the bolted connection type, shape, design, bolted connection quality, and the bolted connection loading. |
|
Miscellaneous-effects Factor |
All other effects that can reduce or increase the fatigue strength of bolted connection (for example, the influence of corrosion) are included in this coefficient. |
Results
To display the Results area on the right side of the Calculation and Design tabs, double-click the double line on the right or click the chevron.
Displays calculated forces and stresses in the bolt and pressure in the nut thread. Click Calculate to display the values
For information about formulas for the bolted connection calculation, see Engineer's Handbook
.Following output parameters are displayed in the Results pane:
- Corrected Endurance Limit (σ e )
- Virtual Mean Stress (S e / Ψ) (σ F )
- Mean Fatigue Strength of the Joint (σ M )
- Amplitude of Joint Fatigue Joint Stress (σ A )
- Mean Cycle Stress of the Joint (σ m )
- Cycle Stress Amplitude (σ a )
- Calculated Safety Degree (n c )
Summary of Messages
Displays the reports about calculation. To open the Summary of Messages area at the bottom of the Calculation and Design tabs, double-click the double line at the bottom of tabs or click the chevron at the bottom of the tabs. The Message area incorporates a summary for all calculations (state and fatigue).