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Rigid pavements have sufficient flexural strength to transmit the wheel load
stresses to a wider area below.
A typical cross section of the rigid pavement is shown in Figure 1.
Compared to flexible pavement, rigid pavements are placed either
directly on the prepared sub-grade or on a single layer of granular or
stabilized material.
Since there is only one layer of material between the concrete and the
sub-grade, this layer can be called as base or sub-base course.
Figure 1:
Typical Cross section of Rigid pavement
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In rigid pavement, load is distributed by the slab action, and the pavement
behaves like an elastic plate resting on a viscous medium (Figure 2).
Rigid pavements are constructed by Portland cement concrete (PCC) and
should be analyzed by plate theory instead of layer theory, assuming
an elastic plate resting on viscous foundation.
Plate theory is a simplified version of layer theory that assumes the
concrete slab as a medium thick plate which is plane before loading and to
remain plane after loading.
Bending of the slab due to wheel load and
temperature variation and the resulting tensile and flexural stress.
Elastic plate resting on viscous foundation
Deflection on concrete pavement
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