Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Back-Face Strain Compliance Calibration for the Four-Point Bend Specimen

  • Huh, Yong-Hak (Material Evaluation Center, Korea Research Institute of Science and Standards) ;
  • Song, Ji-Ho (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology)
  • Published : 2000.03.01
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Abstract

Back-face strain compliance (BFS compliance) for the four-point bend specimen has been calibrated for various crack length ratios. Finite element technique was employed to simulate four-point loading and calculate back-face strain of the bend specimen. The numerically determined strain variation along the back face indicates that the sensitivity to gage placement increases with crack length and back-face strain at the gage length less than O.2W, where W is the width of the bend specimen, can be measured within 5% deviation of the maximum BFS. Non-dimensional back-face strain compliance, -E'BCW, was calibrated with FE analysis and experiment. The experimentally determined compliance indicates good agreement with the numerical compliance and can be expressed as a function of crack length ratio.

Keywords

References

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