MEASUREMENT OF MODE-I STRESS INTENSITY FACTOR IN A DOUBLE-CRACKED COMPOSITE SHEET USING DIGITAL IMAGE CORRELATION METHOD

Abstract

Abstract: Digital image correlation method was used to measure mode-I stress intensity factor in a double-cracked composite sheet. First, the principle of DIC was introduced, and the relationship between the stress intensity factor and the displacement at the crack tip was established based on least square fitting. Then, the non-contact optical measurement system of DIC was built up, and the full field displacements at the crack tip were obtained by tensile experiments using double-cracked composite sheets. Finally, the stress intensity factors were extracted from the full field displacements, and the effects of least square fitting terms, sub size and sub spacing of DIC on the stress intensity factors were analyzed.

Key words: composite sheet, digital image correlation method, least square fitting, stress intensity factor, crack

CLC Number:

TB332
O348.1

HAO Wen-feng, YUAN Ya-nan, YAO Xue-feng, MA Yin-ji. MEASUREMENT OF MODE-I STRESS INTENSITY FACTOR IN A DOUBLE-CRACKED COMPOSITE SHEET USING DIGITAL IMAGE CORRELATION METHOD[J]. COMPOSITES SCIENCE AND ENGINEERING, 2015, 0(4): 22-26.

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