GATE Civil Engineering (CE) 2019 Shift 1 Solved Paper

An isolated concrete pavement slab of length $\mathit{L}$ is resting on a frictionless base. The temperature of the top and bottom fibre of the slab are ${\mathit{T}}_{\mathit{t}}$ and ${\mathit{T}}_{\mathit{b}}$, respectively. Given: the coefficient of thermal expansion $=\mathit{\alpha }$ and the elastic modulus $=\mathit{E}$ Assuming ${\mathit{T}}_{\mathit{t}}>{\mathit{T}}_{\mathit{b}}$ and the unit weight of concrete as zero, the maximum thermal stress is calculated as