Nonlinear Finite Element Analysis of Concrete Structures

- 86 -
(4.3-6)
where the material matrix Di and the initial strain vector
e" due to temperature take different forms depending on the
reinforcement type.
For tangential reinforcement that carries forces only in the
tangential direction, cf. fig. 1 a), we have
0 0 0
b,tan.
0 1 0
e' . = OLLT
ob,tan.
(4.3-7)
0 0 0
where, as usual, E is Young's modulus, a the coefficient of
thermal expansion and AT the mean temperature rise of the bar
element in question.
RZ-reinforcement, cf. fig. 1 b), carries load in the RZ-plane.
In addition to the load in the bar direction, shear stresses due
to dowel action might be considered, i.e.
1 0
0
D b,RZ
0 0
0
ob,RZ
= aAT (4.3-8)
0 0
K
2(l+v)
where v is Poisson's ratio for the reinforcement material and
K is factor, 0 < * < 1, which implies that the full shear capacity
of the reinforcement cannot be utilized due to, for instance,
local crushing of the concrete. As explained previously