A Self-Learning Manual - Institution of Engineers Mauritius

A Self-Learning Manual
Mastering Different Fields of Civil Engineering Works (VC-Q&A Method) Vincent T. H. CHU
increase the thickness of corners and edges to reduce the induced
stresses. However, such local thickenings also increase temperature
stresses. Moreover, the construction of non-uniform concrete pavement is
not convenient from practical point of view. The other way out is to use load
transfer devices like dowel bars at the edges of concrete panels. However,
in situation where the designed thickness of concrete pavement is small
which renders the provision of dowel bars not practical, special design of
corner reinforcement has to be considered [21].
18. Should engineers design acute angle for concrete pavement?
(PS8)
The stress induced in acute angle corners of concrete pavement is far
much higher than that in right-angle corners of the pavement. For instance,
concrete pavement corner of acute angle of 70 o induces stresses about
50% more than the stress induced by an angle of 90 o . As a result, corners
of concrete pavement should not be designed with acute angles to avoid
corner cracking. If it is necessary to adopt acute angles for concrete
pavement, special reinforcement has to be provided to strengthen these
corners [55].
Fig. Acute angle of concrete pavement
19. There is an optimum time to saw contraction joints in new
concrete pavement. Why? (C2)
There is an optimum time to saw contraction joints in new concrete
pavement. Sawing cannot be carried out too early because the saw blade
would break out particles from pavement and this results in the formation of
jagged and rough edges. Such raveling is undesirable as it would impair
the appearance and the ability to seal the joint properly.
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