Civil Engineering Reference
In-Depth Information
9.5
Elastic stress distribution in deep beam by finite element method
If it is only required to obtain a pattern of the stress distribution in a deep
beam for preliminary study or design purpose, one can proceed by
assuming the reinforced concrete beam as an elastic isotropic plate,
discretising the beam with triangular and/or rectangular elements,
assembling the element stiffness matrices and setting up equilibrium
equations for the nodes. The nodal displacements can be solved and the
element principal stresses calculated.
Figure 9.5
shows the distribution of
the magnitude and direction of the principal stresses in a simply supported
deep beam with a span/depth ratio of 2.0 subjected to a uniformly
distributed load applied at the top.
9.6
Finite element model for cracked reinforced concrete
However, the linear elastic solutions and stress distributions will have little
meaning once cracking of concrete occurs, and a more sophisticated finite
element model which can make a realistic representation of reinforced
concrete and take into account the actual complexity of the construction
should be employed.
