Stress calculation method for power transmission tower nonlinear flexible member

The invention discloses a stress calculation method for a power transmission tower nonlinear flexible member. The stress calculation method comprises the steps of firstly selecting a structural model and a material model according to the structural composition and material of a tower, respectively generating a stiffness matrix, a nodal displacement array and a nodal load array of tower member units according to each tower member unit and node displacement; secondly, adopting a finite increment method and a Newton iteration method to correct an obtained stress matrix and an obtained displacement matrix; finally, conducting Lagrange's interpolation on the stress matrix and the displacement matrix of the tower to obtain overall load and displacement of the tower and accordingly obtaining the stress at any point position in a tower structure. The stress calculation method directly conducts effective calculation on the stress of the power transmission tower nonlinear flexible member by means of a mathematical method and can provide an important scientific basis for safety evaluation of the tower structure.