Region of Research

 The structural engineering for steel structures employs recently a performance-based design, in contrast to the traditional prescriptive specification, to meet measurable or predictable performance requirements for safe and secure infrastructures. Nevertheless, the fatigue design rule in each country adopts the conventional approach with the strength grade diagram, while knowing that most failures of steel structures are controlled by fatigue. Such conservatism is attributed to the incompatibility between stress fields in the laboratory specimen and structural components. The International Research Center for Fatigue Design of Weld Structures aims at developing an advanced methodology to prevent fracture and to ensure the safe operation of structures from a stage of designing structures. The key concept is the visualization of crack performance, leading to fatigue free structures, with the standardization of fatigue assessment procedure.

Current Research Subjects

  1. Critical review of current studies on fatigue design
  2. Link between fatigue initiation at structural discontinuity and fracture mechanics approach
  3. Constraint-based assessment of fatigue
  4. Development of fatigue tests leading to fracture performance design for weld structures
  5. International standardization of performance oriented design for fatigue assessment
F. Minami
Assoc. Prof.
S. Tsutsumi
Asst. Prof.
Y. Talashima
G. Prof.
M. Toyosada
G. Prof.
K. Terada

Example of welding related fatigue problems and the representative scales

Example of fatigue life sensitivity on local geometries (Analysis)

Example of predicted fatigue life based on cyclic plasticity model (Analysis)

Example of extremely low-cycle fatigue problem under complex loading condition (Analysis)

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