Question

For plane elasticity problems, which option represents the essential boundary conditions among the governing equations?

(a) Displacements, ux and uy  at the boundary

(b) Surface traction at the boundary

(c) The displacements (ux and uy) and surface traction at the boundary

(d) Stresses in the element

The question was posed to me in an international level competition.

This key question is from Plane Elasticity in portion Plane Elasticity of Finite Element Method

Answer 1

Correct choice is (a) Displacements, ux and uy  at the boundary

The best explanation: For plane elasticity problems, the boundary conditions are one of the governing equations. There are two types of boundary conditions, namely, essential boundary conditions and natural boundary conditions. The displacements specified in the problem are the essential boundary condition or Dirichlet boundary condition.