Question

Which option is not correct concerning the internal load vector in the finite element model of plane elasticity problems?

(a) It is computed at all the nodes interior of the element

(b) It is computed only when the element falls on the boundary of the domain on which tractions are known

(c) Its computation doesn’t involve evaluation of line integrals for any type of element

(d) It is evaluated in global coordinates but not in element coordinates

This question was posed to me in an online interview.

I want to ask this question from Plane Elasticity topic in division Plane Elasticity of Finite Element Method

Answer 1

Right answer is (b) It is computed only when the element falls on the boundary of the domain on which tractions are known

For explanation I would say: In Finite Element Analysis, internal load vector Q is computed only when the element falls on the boundary of the domain on which tractions are specified (i.e., known). Computation of Q involves the evaluation of line integrals (for any type of element). In practice, it is convenient to express the surface traction t in the element coordinates. In that case, Q can be evaluated in the element coordinates and then transformed to the global coordinates using a transformation matrix.