Tools › Structures › Stress Concentrations › Round Hole Finite Strip › Example
Round hole in a finite strip, D/W = 0.25: K_tg = 3.248, K_tn = 2.436 against Heywood's 2 + (1 − D/W)³
| Tool | Round Hole Finite Strip |
| Source | Heywood, R. B. (1952). Designing by Photoelasticity. Chapman and Hall, London (K_tn = 2 + (1 − d/W)³); Howland, R. C. J. (1930). "On the Stresses in the Neighbourhood of a Circular Hole in a Strip under Tension." Philosophical Transactions of the Royal Society of London, Series A, Vol. 229, pp. 49–86. |
| Level | Professional |
Problem
A long strip 1 in wide and 0.1 in thick with a central 0.25 in hole carries 5,000 lb. Find the gross and net nominal stresses, the gross and net stress concentration factors, the hoop stress on the load axis and the stress at the strip edge on the net section.
Inputs to Enter
- P = 5000 lb, t = 0.1 in
- W = 1 in, D = 0.25 in (D/W = 0.25)
- r = 0.125 in, θ = 90°
Answers
- σ_g = 50 ksi, σ_n = 66.67 ksi
- K_tg = 3.248, K_tn = 2.436 (Heywood 2 + 0.75³ = 2.422)
- Hoop stress at θ = 0 (load axis): −1.181 σ_g; strip-edge σ_yy on the net section: 0.685 σ_n
Notes
The tool's default inputs are this case. The page prints K_tn,Heywood beside the series value; Heywood's formula is within 1 % up to D/W = 0.3 and 2–3.5 % low beyond.