شبكة التخطيط العمراني بسم الله الرحمن الرحيم
للكاتبين :
A. A. Abdel-Alhadya, M. H. Seleemb, Y. Fouadc and H. E. M. Sallamb
a Mechanical Design Department, Mataria, Helwan University, Cairo, Egypt.
b Materials Engineering Dept., Faculty of Eng., Zagazig University, Zagazig, Egypt
c Mechanical Engineering Dept., Higher Technological Institute, Tenth of Ramadan, Egypt
ABSTRACT
The stress intensity factor is a traditional topic in mechanics and there have been many solutions
for many different cases. The crack problem which is emanating from elliptical oblique notch has
been studied previously under uniaxial load. Further, the study of SIF of short crack emanating
from notch under biaxial loading has not been considered in the literature. A plane stress elastictwo
dimensional finite element model was adopted to estimate mode I stress intensity factor
(SIF), stress concentration factor, (SCF), crack tip opening displacement (CTOD) and site of
crack initiation for biaxially loaded plate containing central elliptical oblique notch. Biaxial
loadings of different patterns, i.e. tension-tension or tension-compression were studied. Notches
of variable depths (D), (D= 2 and 4 mm) and variable radius (ρ), (ρ = 0.5 and 1 mm) were
studied. The effect of biaxial ratio, λb (the ratio of the two involved axial normal stresses) (λb= -1to 1) and notch angles (
θ), (θ= 0o, 15o, 30o and 45o) were investigated. Stress distribution at the
surface of the notches was analyzed to detect the point of maximum equivalent stress and
subsequently locating the site of crack initiation.
The highest equivalent stress on the surface of inclined notch was found at the point that has the
largest horizontal coordinate (= horizontal projection), i.e. site of crack initiation. The SCF
increased with increasing the biaxial ratio. In the case of tension-tension biaxial loading, the
mode I SIF decreased with increasing the biaxial ratio.