For instance, an unreinforced concrete carriageway is constructed in

winter. When temperature rises in the following summer, the section between expansion joints will expand as a whole single element resulting in the closure of expansion joints.

This section of concrete pavement will move outwards from the mid-point between the expansion joints. In the next winter, each bay (i.e. concrete pavement between adjacent contraction joints) of concrete contracts about the midpoint of its length with opening ofcontraction joints.

Thanks dr. abbas for your valuable answer

Not at all Dr Amjad