Civil Engineering Reference
In-Depth Information
constitutive relationships of embedded mild steel. The tensile stress-strain relationships of
embedded tendons as per SMM for prestressed concrete are given in Equations (9.16) and
(9.17). The initial prestressing strain in the tendons is also implemented as an input parameter
in this module.
0
.
7
f
pu
E
ps
f
ps
=
E
ps
¯
ε
s
,
ε
s
<
¯
(9.16)
E
ps
¯
ε
s
0
.
7
f
pu
E
ps
f
ps
=
5
,
ε
s
≥
¯
(9.17)
⎡
5
⎤
⎦
E
ps
¯
1
ε
s
f
pu
⎣
1
+
where:
where
f
ps
=
stress in prestressing tendons for a given uniaxial strain ¯
ε
s
E
ps
=
elastic modulus of prestressing tendons taken as 200 GPa (29 000 ksi)
f
pu
=
ultimate strength of prestressing tendons taken as 1862 MPa (270 ksi),
E
ps
=
modulus of prestressing tendons, used in plastic region, taken as 209 GPa
(30 345 ksi)
f
pu
=
revised strength of prestressing tendons taken as 1793 MPa (260 ksi)
9.2.2.3 ConcreteL01
The concrete module ConcreteL01 was developed according to the cyclic uniaxial concrete
model of CSMM for prestressed concrete (Figure 9.7). This cyclic uniaxial concrete model
considers the softening effect due to the perpendicular tensile strain on the concrete struts.
Figure 9.7
ConcreteL01 material model
