In this seminar, participants will learn how to measure strain and calculate the stress, how to sum-up loads with a rainbow matrix and how to estimate lifetime using a S-N curve
The material S-N curve
for shear can be measured with specimens consisting of [+ or -]45[degrees] lay-ups, see Figure 4.
the log number of cycles-to-failure resulted in a linear S-N curve
Battelle describes it as the mesh-insensitive structural stress method and says it is also called the master S-N curve
method, because it can "correlate a massive amount of actual fatigue test data into a single S-N curve
Figure 5 also shows the S-N curve
for the specimens containing the weld line.
Experimental Verification of the Analytical Method for Estimated S-N Curve
in Limited Fatigue Life
The parameters of the S-N curve
were determined based on the test results, according to , defining a method to calculate the parameters including run-outs and run-out specimens re-tested at higher load levels.
Fatigue strength versus life is a stress-life curve, also called an S-N curve
Standard S-N curves
for both load and stress amplitude are obtained from the test data.
Appropriate S-N curves
are presented for the assessment of the fatigue strength of different materials.
Design S-N curves
for use with the structural hot spot stress are presented for a range of weld details.
After an introduction, chapter two introduces the constant amplitude database, which contains results obtained in test conditions and which forms the basis of the basic S-N curves
for various types of joint.