Question

The concrete sections of a certain superhighway are designed to have a length of 23.0 m. The sections are poured and cured at 10.0°C. What minimum spacing should the engineer leave between the sections to eliminate buckling if the concrete is to reach a temperature of 42.0°C?

Answer 1

Answer:

0.88 cm

Explanation:

Initial length at 10°c, L = 23 m

Rise of temperature, Δt = 42 - 10 = 32°c

Coefficient of linear expansion of concrete, α = 12 x 10^(-6) per°c

Minimum spacing to be left = α L Δt

$=12\times10^{-6}\times23\times32$

$=8.832\times10^{-3}m$

= 8.832 x 10^{-1} cm

= 0.88 cm

Note: I have a chosen a general value of 12 x 10^-6 per deg c for coefficient of expansion of  concrete. However, please refer to the value given in your text book and substitute it for an accurate answer.