802 薄層平織CFRP積層板の切欠強度のプライスケールおよびサブラミネートスケール依存性(OS8-(1),OS8 オーガナイズドセッション≪複合材料の変形と破壊およびマルチスケール計算技術≫)

Abstract

Size effect on the static tensile fracture strength of thin-ply woven carbon fiber composite laminates as well as its stacking sequence dependence is studied. Applicability of existing strength models to the notch size and scale dependent tensile fracture strength is also examined. Two kinds of woven fabric composites ([(0/90)_n/(±45)_n]_s and [(0/90)/(±45)]_<ms>) are tested. To observe the effect of specimen size, static tension tests are performed on 1D, 2D and 3D-geometrically similar specimens. Unnotched (UN) and double-edge notched (DEN) were prepared for each size, respectively. To elucidate the size effect on notch sensitivity, furthermore, 1D, 2D and 3D scaled DEN specimens are tested for different notch lengths, respectively. It is observed that the tensile fracture strength of DEN specimens significantly decreases as the size of specimen increases. As the specimen size decreases, the tensile fracture behavior gradually shifts from a LEFM-dominated region to an UN-strength-dominated region.