The value of the limit temperature gradient Δtl follows for the center of a
longitudinal edge (plain concrete pavement) from equalizing the equations 21
and 22a and for the center of a transverse edge or transverse crack
(reinforced concrete pavement) from equalizing the equations 21 and 22b.
The determination of Δtl is an iterative calculation.
It is however not necessary to calculate the limit temperature gradient Δtl. The
actual temperature gradient stress σt in the centre of the longitudinal edge is
the smallest value resulting from the equations 21 and 22a, and similarly the
actual temperature gradient stress σt in the centre of the transverse edge or
crack is the smallest value resulting from the equations 21 and 22b.
To obtain the temperature gradient stresses along an edge or crack of the
concrete slab equation 20 can be used.
The temperature gradient stresses calculated by means of this Dutch method
are in good agreement with finite element calculation results (12,13,14).