ABSTRACT
The deleterious effects that water can have on pavement performance are explored in
Chapters 8, 11 and 14. Water movement within a pavement can be considered as
occurring in three phases:
(a) an entry phase (Figure 9.1), which occurs quite rapidly;
(b) a redistribution phase (Figure 9.1) when water moves within the pavement in
response to soil suction (Section 9.2.4) and gravity; and
(c) an evaporative phase when water, as vapour, leaves a material or moves to other
layers. Water vapour movements can occur under temperature gradients, with
the vapour travelling from a warm to a cool area where it then condenses.
