Abstract:As a high level statically indeterminate structure, the cable forces of cable-stayed bridge are often need to be computed tautologically both when doing FEM structural analysis or construction observation computing of bridge. This time consuming computing process also need well training on analytical mechanics and deep insight to the behavior of bridge structure. In this work, an influence matrix and particle swarm intelligence optimization algorithm based cable force adjustment computing Algorithm are proposed, with the aims to realize the automatic cable force adjustment when facing the cable stayed bridge structural analysis or construction observation computing tasks. The cable force adjustment is modeled as an auto resolution space searching process with the optimization objective expressed by influence matrix of bridge, and particle swarm intelligence optimization algorithm replaces the tautological manual tentative calculation. The programs are developed and applied to the true cable stayed bridge, and the result showed that in most cases, a rational resolution for cable force collection can be arrived at handily and promptly, without any manual interventions. And in all case, the relative errors are under controlled less than 2%. The proposal method is expected to provide a efficient resolution or guideline for structural FEM analysis and construction observation computing on cable stayed bridge.