The Suspension Bridge Nonlinear Finite Element Static Analysis And Program Design

Suspension bridges are long-span bridges supported by cables. Because of their long span ability and light beautiful structures, suspension bridges are competitive bridge types of long-span bridges.Starting with the theoretical development of suspension bridges, this thesis introduces the basic principle of linear-elastic theory, deflection theory and finite displacement theory, and through the comparative analysis to the three, proves under the background that the computer develops and uses at a high speed now, finite displacement theory is the best theory that analyses the structure of suspension bridges.This thesis has considered the three primary geometric nonlinearity factors of suspension bridges: the cable sagging effect, the large deflection effect due to changes in geometry and the influence of initial strains, and carry on static structure analysis to the structure of suspension bridges with 2D finite-element models on the basis of Updating Lagrange form foundation.The equations of nonlinearities are solved by the Newton-Raphson method based on increment-iterationwise.The Suspension Bridge Static Analysis program (SBSA) is developed in VB program language in this thesis. To verify the program a certain suspension bridge of spans of 230 m + 648 m +230 m is used as an example. It indicates that the results of program are reliable by the program. So, the program has certain practical value of project.