笔者用有限元法进行了分析，给出了单元的线性刚度矩阵和增量刚度矩阵。

Finite element method is used in the analysis. The linear incremental and stiff matrices are derived.

youdao

因而，得到的单元切线刚度矩阵是对称的，此外在增量求解过程中用节点变量的全量进行更新。

As a result, the element tangent stiffness matrix is symmetric and is updated by using the total values of the nodal variables in an incremental solution procedure.

youdao