Nonlinear Finite Element Analysis of Concrete Structures

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the value K = 0 is always assumed except for certain sensitivity
studies cf. also sections 5.1 and 5.3.
Membrane reinforcement, cc. fig. 1 c), carries load both in the
tangential direction and in the RZ-plane. Like the RZ-reinforcement,
shear stresses in the RZ-plane due to dowel action might
be considered, i.e..
V
1
*b. mem. 1-V
0
0
0
K(l-V)
2
E* = aAT
ob,mem.
1
1
i 0
V J
(4.3-9)
where in general the value K = 0 again is assumed.
From the standard finite element formulation given by eqs.
(4.1-19) to (4.1-25) and noting the constitutive equation (6)
the reinforcement element is described by
R; a,* = F'
b b e o b (4.3-10)
where the reinforcement element stiffness matrix is given by K',
the nodal displacements a' are given by eq. (1) and the vector
F' . describes the nocal forces due to temperature loading. The
stiffness matrix is given by
R i = f g b T B ;
bar vol.
B' dV = §' T D* B' 2