Jawaharlal Nehru Technological University Hyderabad B.Tech III AIRCRAFT STRUCTURAL ANALYSIS Previous Question Paper (November/December - 2018 - R16)

Calculate total strain energy (U) produced by bending and twisting for a rectangular plate of dimensions a × b.

Determine the position of the shear centre S for the thin-walled, open cross section shown in Figure 2. The thickness t is constant.

Find the position of the shear centre of the rectangular four boom beam section shown in Figure 3. The booms carry only direct stresses, but the skin is fully effective in carrying both shear and direct stress. The area of each boom is 100mm2.

Determine the shear flow distribution at the built-in end of a beam whose cross-section is shown in Figure 4. All walls have the same thickness t and shear modulus G, R=200 mm.

A uniform four boom box of span 5m is 500mm wide by 20mm deep and has four corner booms each of cross-sectional area 800 mm2, its wall thickness is 1.0 mm. If the box is subjected to a uniformly distributed torque loading of 20 Nm/mm along its length and it is supported at each end such that complete freedom of warping exists at the end cross-sections calculate the angle of twist at the mid-span section. Take G=20,000 N/mm2 and G/E = 0.36.

The cantilever beam shown in Figure 5 is uniformly tapered along its length in both x and y directions and carries a load of 100 kN at its free end. Calculate the forces in the booms and the shear flow distribution in the walls at a section 2m from the built-in end if the booms resist all the direct stresses while the walls are effective only in shear. Each corner boom has a cross-sectional area of 900mm2 while both central booms have cross-sectional areas of 1200mm2.