journal article·2024-05Open access

FKM-guideline “Analytical strength Assessment” – Background and current developments

Roland Rennert, Michael Vormwald, Alfons Esderts

Abstract

The FKM-Guideline “Analytical Strength Assessment” contains an algorithm for both static and the fatigue strength assessment of components made of steel, cast iron, and aluminium alloys. Designed to be advantageous for industrial applications, this guideline expresses the design stress using a straightforward linear-elastic material behaviour. Starting with the material strength properties specified in technical standards, the relevant component properties for both static and fatigue strengths can be determined by considering all influencing factors. The safety level required for assessment can be adjusted using experience-based safety factors. The outcomes of the analytical strength assessment provide a measure of the degree of utilisation. While the FKM-Guideline has been successfully applied since 1994, continuous further development is necessary to ensure it remains at the forefront of industry standards. Key development areas include the improvement of the critical strain curve, introduction of a coordinate-invariant fatigue strength assessment procedure, conducting investigations on the accuracy of the calculation according to the FKM-Guideline as a precondition for the development of a probabilistic safety concept, and extension of the FKM-Guideline to additional material groups such as high-strength steel.
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Research context

OpenAlex topics: Fatigue and fracture mechanics · Structural Behavior of Reinforced Concrete · Probabilistic and Robust Engineering Design

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