Involvements of Stress Triaxiality in the Brittle Fracture during Earthquakes in Steel Bridge Bents

다국어 초록 (Multilingual Abstract)

Stress triaxiality is proposed as one of the key parameters to discuss the cause of brittle fracture during earthquakes in steel
structures. This study analytically investigated the features of stress triaxiality in steel bridge bent subjected to earthquakes. The
target structure is a steel bridge bent actually fractured during the South Hyogo prefecture Earthquake. From the investigations,
it was confirmed that high stress triaxiality was generated at a point supposed as fracture origin. There is a possibility that the
triaxiality was involved in the fracture strongly through the increase of maximum principal stress. Moreover, from the analyses
accounting for several kinds of large earthquake waveforms, it was indicated that threre is possibility that the distribution of
triaxiality around the fracture origin was not affected by significantly by each cycle and each waveform.

다국어 초록 (Multilingual Abstract)

Stress triaxiality is proposed as one of the key parameters to discuss the cause of brittle fracture during earthquakes in steel
structures. This study analytically investigated the features of stress triaxiality in steel bridge bent subjected to earthquakes. The
target structure is a steel bridge bent actually fractured during the South Hyogo prefecture Earthquake. From the investigations,
it was confirmed that high stress triaxiality was generated at a point supposed as fracture origin. There is a possibility that the
triaxiality was involved in the fracture strongly through the increase of maximum principal stress. Moreover, from the analyses
accounting for several kinds of large earthquake waveforms, it was indicated that threre is possibility that the distribution of
triaxiality around the fracture origin was not affected by significantly by each cycle and each waveform.

참고문헌 (Reference)

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