Answer :
To calculate the expansion gap necessary for steel rails laid at 20°C to accommodate expansion at a maximum temperature of 55°C, apply the linear thermal expansion formula ΔL = αLΔT with the coefficient of linear expansion for steel.
Calculating the Expansion Gap for Steel Rails
When steel rails are laid at an initial temperature of 20°C, and the maximum temperature they are expected to reach is 55°C, there will be an expansion due to the increase in temperature. To find out how large an expansion gap should be left between the rails, we use the equation for linear thermal expansion ΔL = αLΔT, where ΔL is the change in length, α is the coefficient of linear expansion for steel, L is the original length of the steel rails, and ΔT is the change in temperature.
The standard coefficient of linear expansion for steel is approximately α = 12 × 10-6 °C-1. Given that the change in temperature (ΔT) is 55°C - 20°C = 35°C, and assuming the original length of each rail (L) is 10.0 m, the equation to find the expansion gap (ΔL) becomes:
ΔL = (12 × 10-6 °C-1) × 10.0 m × 35°C
By calculating ΔL, we can determine the size of the gap necessary to prevent stress in the rails due to temperature-induced expansion.
