A plastic material has creep behaviour at 20 oC which can be given by: with J0 = 0.24 GPa-1, J1 = 0.22 GPa-1s-0.4 and n = 0.4 A pipe of this material has a diameter of 7.3 cm, and a wall thickness of 5 mm. The pipe is filled with water and the pressure is increased at a constant rate of 2 kPa.s-1 starting at t = 0 until it reaches 607 kPa. The pressure is then held at 607 kPa. What would the maximum strain in the pipe be 2 hours after the pressure started to increase (when t = 2 hours)? The temperature is 20 oC throughout. Give your answer as a number, with no units to 4 dp (ie don't use standard notation). You have an error margin of 2%.

Consider the simplified stress-strain curve of mild steel shown in the figure below. Only the strains as shown in the figure are known at the critical points. If the ultimate strength is 1.5 times the yield strength, the energy absorbed by this steel per unit volume up to the point U is: U Y S O: ɛ = 0 .F Y: ɛ = 0.002 Young's Modulus, E = 29,000 ksi S: ɛ = 0.02 U: ɛ = 0.1 F: ɛ = 0.15 Strain Stress (ksi)

Find the heat flow rate through the composite wall as shown in the following figure. Assume one dimensional flow and take k 1 = 150 W/m degree, k 2 = 30 W/m degree, k 3 = 65 W/m degree, k 4 = 50 W/m degree. AB = 3 cm, BC = 8 cm and CD = 5 cm. The distance between middle horizontal line from the top is 3 cm and from the bottom is 7 cm.

The depicted in the figure below has a length of 0.635m and a diameter of 50mm. The bar is made of a copper alloy with an elastic modulus E = 110 GPa and a linear thermal expansion coefficient a = 17.5 × 10-6/°C. The bar is initially positioned at room temperature with a gap of 0.2mm between end A and the rigid wall. The bar's right end at B is supported by an elastic spring of negligible thermal expansion coef- ficient and a spring constant of k = 210 × 10°N/m. A small gap maintained between the copper bar and the smooth surrounding sleeve facilitates frictionless motion as the bar thermally expands. Questions: (a) Compute the temperature increase ATer required to close the 0.2 mm gap. (b) Compute the axial force R developed in the copper bar due to a temperature increase of AT = 27°C. State the compatibility condition and solve it for R. (c) Compute the compressive (engineering) stress o developed within the copper bar due to the axial force R. Express your answer in MPa. (d) Compute…