Finite Element Method – I Amir R.
Khoei
HW #3. Civil Engineering Department
Sharif University of Technology
Consider two higher order beam elements of length ℓ and flexural rigidity EI , as shown in Figure.
Model (a) is 2-noded element with three-degrees of freedom (υ, θ, κ) at each node. Model (b) is 3-
noded element with two-degrees of freedom (υ, θ) at each node.
1 κ1 κ2 2 1 2 3
θ1 θ2 θ1 θ2 θ3
υ1 υ2 υ1 υ2 υ3
ℓ ℓ
model (a) model (b)
1. Determine the shape functions of elements (a) and (b).
2. Determine the stiffness matrix of elements (a) and (b).
3. Consider that the elements are subjected to the uniform distributed loading with intensity q
per unit length, determine the vector of equivalent nodal force for each element.
4. Consider the cantilever beam shown in figure, determine the variations of vertical
deformation along the beam in the following cases;
a. Using four-elements of type (a).
b. Using four-elements of type (b).
c. Using four-simple-beam-elements of 2-nodal points with (υ, θ) at each node.
q = 5000 Kg/m
ℓ= 8 m