Skip to main content

Cylindrical shell: stresses, max shear and volume change

Short answer

Circumferential stress σ_c = 125.0 N/mm², longitudinal σ_l = 62.5 N/mm². Max shear stress = 31.25 N/mm². Volumetric strain ε_v = 1.1875×10⁻³ gives δV = 3731 cm³ (increase).

A cylindrical shell 4m long and 1m diameter is subjected to an internal pressure of 2 N/mm22\ \text{N/mm}^2. If the thickness of the shell is 8mm, find the circumferential stress and longitudinal stress. Find also the maximum shear stress and change in volume.

Data: L=4000L = 4000 mm, d=1000d = 1000 mm, p=2 N/mm2p = 2\ \text{N/mm}^2, t=8t = 8 mm. The change in volume needs EE and ν\nu; they are not given, so the usual values for steel are taken: E=2×105 N/mm2E = 2\times10^5\ \text{N/mm}^2 and ν=0.3\nu = 0.3.

Stresses

σc=pd2t=2(1000)2(8)=125.0 N/mm2,σl=pd4t=62.5 N/mm2\sigma_c = \frac{pd}{2t} = \frac{2(1000)}{2(8)} = 125.0\ \text{N/mm}^2, \qquad \sigma_l = \frac{pd}{4t} = 62.5\ \text{N/mm}^2

Maximum shear stress

τmax=σc−σl2=125.0−62.52=31.25 N/mm2\tau_{max} = \frac{\sigma_c-\sigma_l}{2} = \frac{125.0-62.5}{2} = 31.25\ \text{N/mm}^2

Change in volume

εv=pd4tE(5−4ν)=2(1000)4(8)(2×105)(5−1.2)=1.1875×10−3\varepsilon_v = \frac{pd}{4tE}(5-4\nu) = \frac{2(1000)}{4(8)(2\times10^5)}(5-1.2) = 1.1875\times10^{-3} V=π4(1000)2(4000)=3.1416×109 mm3,δV=εvV=3.7306×106 mm3=3731 cm3V = \frac{\pi}{4}(1000)^2(4000) = 3.1416\times10^{9}\ \text{mm}^3, \qquad \delta V = \varepsilon_v V = 3.7306\times10^{6}\ \text{mm}^3 = 3731\ \text{cm}^3

Answer: σc=125.0\sigma_c = 125.0 N/mm², σl=62.5\sigma_l = 62.5 N/mm², τmax=31.25\tau_{max} = 31.25 N/mm², δV≈3731\delta V \approx 3731 cm³ (increase).

✓ Answer checked by Claude Opus 5.5 (high effort)

All Strength of Materials chapter 5 questions →