In order to consider the action of concrete among cracks in tensile area, a factor for released force, ZC, is proposed in the treatment of failure elements and analysed on the basis of studies in nonlinear behaviours of the whole process.

• 为了考虑裂缝间受拉区混凝土的工作；在破坏单元处理中提出了释放力系数ZC；并在全过程非线性研究的基础上对系数ZC进行了分析.