A generally applicable approximate solution for mixed mode crack-inclusion interaction

Journal of Adhesion Science and Technology

Yuan

et al. 2015

The effect of inclusion shape on the mode I stress intensity factor of the matrix crack interaction with a rigid inclusion was studied experimentally using digital gradient sensing (DGS) method. First, the noncontact optical measurement system of DGS was built up, and the specimens with different shapes of inclusion ahead of matrix crack were performed using transparent epoxy resin. Then, the angular deflection contour at the crack tip with different shapes of inclusions was obtained, and the stress intensity factors were extracted from the stress gradient filed based on least square fitting. Finally, a numerical simulation was conducted on the same problem using ABAQUS, and the stress intensity factors computed from FEM were compared with the experimental results. The results show that the stress intensity factors extracted from the stress gradient filed are agreed well with the numerical and theoretical results.

Section: Introductionmentioning

confidence: 99%

Study on the effect of inclusion shape on crack-inclusion interaction using digital gradient sensing method

Hao

Journal of Adhesion Science and Technology

Yuan

et al. 2015

“…Several simple formulas have been developed to predict the variations of stress intensity factors for mode I crack induced by the stiffness and geometry of the near crack-tip inclusion by Li and Chen [5,6]. Later, Li et al [7,8] proposed a generally applicable approximate solution for mixed mode crack-inclusion interaction. In considering this problem, most studies were performed by numerical approaches.…”

Section: Introductionmentioning

confidence: 99%

Study on crack-inclusion interaction using digital gradient sensing method

Hao

Mechanics of Advanced Materials and Structures

2016

The interaction between matrix crack and a round inclusion was studied by the method of digital gradient sensing (DGS). First, the stress fields at the matrix crack tip in the neighbor of a round inclusion were derived based on transformation toughening theory and Eshelby inclusion method, and the effect of the inclusion on the stress intensity factor of the matrix crack was analyzed. Then, the non-contact optical measurement system of digital gradient sensing was built up, and a three point bending test was carried out using a single edge cracked specimen. The mode I stress intensity factor was extracted from the angular deflection of the light rays. Finally, the effect of the inclusion on the angular deflection fields and the stress ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT 2 intensity factor at the crack tip was analyzed experimentally. These results will play an important role for evaluating the fracture mechanism of crack-inclusion interaction in composites.

“…Several simple formulas have been developed to predict the variations of stress intensity factors for mode I crack induced by the stiffness and geometry of the near crack‐tip inclusion by Li and Chen . Later, Li et al proposed a generally applicable approximate solution for mixed mode crack‐inclusion interaction. In considering this problem, most studies were performed by numerical approaches.…”

Section: Introductionmentioning

confidence: 99%

A study of crack‐fiber interaction in fiber‐reinforced composites using optical caustic method

Polymer Engineering & Sci

2014

In this article, the matrix crack‐fiber buddle interaction in fiber‐reinforced composites is investigated analytically and experimentally. First, the influence of the fiber buddle on the matrix crack is analyzed based on Eshelby equivalent inclusion method. Then the effect of dimensions and material properties of the fiber buddle on the stress intensity factor (SIF) of the matrix crack is studied numerically. Finally, a low velocity impact experiment of fiber‐reinforced composites with a matrix crack is conducted using optical caustic method to verify the analytical and numerical results. POLYM. ENG. SCI., 55:852–857, 2015. © 2014 Society of Plastics Engineers