In this paper, the elastoplastic incremental finite element method with variable plastic stiffness is used to analyse the surrounding rock stability of underground openings.
本文采用三维弹塑性增量变塑性刚度有限元法计算地下洞室围岩稳定。
2
The stiffnessincremental coefficient of the box girder contributed by prestressed tendons, which is also known as prestress parameter, is established with its .
文中还推得张索对梁刚度提高系数，亦称张力参数，并建立其控制式，便于设计应用。
3
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.