Civil Engineering Reference
In-Depth Information
Figure 5.3
Stresses (MPa) in RC 2-D element with equal steel in two directions (example problem 5.1)
the concrete element (
σ
d
). Express all these stresses in terms of Mohr circles. Assume equal
percentages of steel in both directions, i.e.
ρ
=
ρ
t
, and neglect the tensile strength of concrete
(
σ
r
=
0).
5.1.5.2 Basic Principles for Solution
In the equilibrium (plasticity) truss model, the design of reinforced concrete membrane ele-
ments is based on the yielding of both the longitudinal and transverse steel. Assuming
f
=
f
y
and
f
t
=
f
ty
, and neglecting the tensile stress of concrete (
σ
r
=
0), the three equilibrium
equations, Equations (5.21)
-
(5.23), become
ρ
f
y
=
σ
+
τ
t
tan
α
r
(5.33)
ρ
t
f
ty
=
σ
t
+
τ
t
cot
α
r
(5.34)
1
(
−
σ
d
)
=
τ
t
(5.35)
sin
α
r
cos
α
r
