This paper presents a simplified plastic zone method with consideration of the influences of the plastic zone length on the stiffnessmatrix for elastic-plastic analysis of steel frames.
对于杆件单元，本文采用了一种变刚度的杆单元模型，建立了考虑塑性铰分布长度影响的构件单元刚度矩阵。
2
Using the principle of virtual displacement and a rigid-plastic constitutive model, the stiffnessmatrix of the new contact element was deduced.
采用虚位移原理和刚塑性本构模型，推导了接触单元的刚度矩阵。
3
An explicit expression of stiffnessmatrix for a 3-dimensional beam made of elastic-plastic material is derived in the paper.