STRESS CONCENTRATION FACTORS FOR TWO EQUAL CIRCULAR HOLES IN AN INFINITE PLATE
Theoretical stress concentration factors (K_{t}) of two equal circular holes in infinite plate
can be
calculated by this calculator for tension loads. In addition to
stress concentration factor calculation, the calculator can be used to find
maximum stress values at the edge of the hole if loading parameters are
known. See footnotes of the "Results" table for the necessary equations for the
stress calculations.
There exist some
validity conditions for the equations which are used in the calculations. If input parameters don't satisfy
validity conditions of equations, a warning message is given by the calculator.
The formulas and parameters used in the calculator are given in " List of Equations " section of this page.
Calculator:
Note: Use dot "." as decimal separator.
RESULTS 
LOADING TYPE  INPLANE NORMAL STRESSES 

Parameter 
Symbol 
Value 
Unit 
UNIAXIAL TENSION PARALLEL TO ROW OF HOLES (σ_{1}=σ ,σ_{2}=0) 
Stress concentration factor * 
K_{t} 


 
Maximum tension stress 
σ 



UNIAXIAL TENSION NORMAL TO ROW OF HOLES (σ_{1}=0 ,σ_{2}=σ) 
Stress concentration factor for pointB* 
K_{tB} 


 
Nominal tension stress 
σ_{nom} 



Maximum tension stress at pointB 
σ_{B} 


BIAXIAL STRESS ( σ_{2 }= σ_{1}) 
Stress concentration factor for pointB* 
K_{tB} 


 
Nominal tension stress 
σ_{nom} 



Maximum tension stress at pointB 
σ_{B} 


Note 1: * Geometry rises σ_{nom} by a factor of K_{t} . (K_{t }= σ_{max}/σ_{nom})
Note 2: K_{tB } = (σ_{max}/σ_{nom}) Theoretical
stress concentration factor at point B in elastic range
Definitions:
Stress Concentration Factor:
Dimensional changes and discontinuities of a member in a loaded structure causes variations of stress and high stresses concentrate near these dimensional changes. This situation of high stresses near dimensional changes and discontinuities of a member (holes, sharp corners, cracks etc.) is called stress concentration. The ratio of peak stress near stress riser to average stress over the member is called stress concentration factor.
K_{t}: Theoretical stress
concentration factor in elastic range = (σ_{max}/σ_{nom})
List of Equations:
Reference:

Pilkey, W. D..(2005). Formulas for Stress, Strain, and Structural Matrices .2nd
Edition John Wiley & Sons