本文应用松弛系数表示混凝土材料的徐变物理方程,导出了求解徐变应力的“初应力法”。与初应变法相比,初应力法的物理概念清晰,公式较为简单,公式中的弹性——徐变矩阵、应力矩阵、劲度矩阵与弹性状态的矩阵完全相似,只须将其中的弹性模量代之以“松弛弹性模量”。因此可以方便地参考和应用弹性状态的有限单元法公式来编制程序,进行徐变应力分析。 In this paper, the relaxation coefficient is used to represent the creep physical equation of concrete materials, and the “initial stress method” for solving creep stress is derived. Compared with the initial strain method, the physical concept of the initial stress method is clear and the formula is relatively simple. The elasticity in the formula—the creep matrix, the stress matrix, the stiffness matrix, and the matrix in the elastic state are completely similar, only the elastic modulus of the elastic strain is required. Instead, “relaxed elastic modulus.” Therefore, it is convenient to refer to and apply the finite element method formula of the elastic state to formulate a program for creep stress analysis.