IMPACT OF A WEDGE DISCLINATION DIPOLE ON TIP FIELDS OF A WEDGE CRACK

The elastic interaction between a wedge disclinationdipole and a wedge crack is investigated. The closed form solutions ofcomplex potentials and stress fields are obtained by usingcomplex potential theory. The stress intensity factor at the tip of thewedge crack is also obtained. The shielding or anti-shielding effects of thewedge disclination dipole on the stress intensity factor is evaluated. Theresults indicate that the shielding or anti-shielding effects on the stressintensity factor increase sharply when the wedge disclination dipoleapproaches the tip of the crack. Under certain conditions, the disclinationdipole may weaken the stress intensity near the crack tip. If thecenter of the dipole is fixed, there always exists a critical value ofthe angleof the dipole arm for the shielding or anti-shielding effects to be maximal.In addition, the wedge angle of the crack and the length of the dipole armhave a significant influence on the stress intensity factor.