英语翻译Since the structure is composed of several finite elemen
英语翻译
Since the structure is composed of several finite elements,the individual element siffness matrices and load vectors are to be assembled in a suitable manner and the overall equlibrium equations have to be formulated as [K] =P where [K] is called the assembled stiffness matrix,Q is the vector of nodal displacements and P is the vector of nodal forces for the complete structure.
Step(v):Solution for the unknown nodal displacements
The overall equilibrium equations have to be modfied to account for the boundary conditions of the problem.After the incorporation of the boundary conditions,the equilibrium equations can be expressed as [K] =P
For linear problems,the vector Q can be solved very easily.But for nonlinear problems,the solution has to be obtained n a sequence of steps,each step involving the modification of the stiffness matrix [K] and/or the load vector P.
Step(vi):Computation of element strains and stresses
From the known nodal displacements Q,if required,the element strains and stresses can be computed by using the necessary equations of solid or structural mechanics.
The terminology used n the above six steps has to be modified if we want to extend the concept to other fields.For example,we have to use the term continuum or domain in place of structure,field variable in place of displacement,characteristic matrix in place of stiffness matrix,and element resultants n place of element strains.