Application of 3D Finite Element Software in Web Cracking Analysis of Concrete Box-Girder Bridge

For a curved rigid bridge found vertical cracks in web during the construction process, the finite element software (MIDAS) was used to analysis for the creaking reason for the cast-in-place concrete box bridge. From the analysis of the objectives, the credibility of the results, foundation for modeling, the factors choice for the model and relevant experience are introduced. Including low strength and low elastic modulus of concrete, low grade concretes when the prestressing tendons stretched, longitudinal and vertical tendons excess stretched than the Code permission, as well as the combined effects of these factors results are described in detail, conclude that the poor quality of construction should be the cause of the cracks. By the web of concrete core drilling inspection found that there are more honeycomb holes in the web which is the direct cause of cracks and verified the finite element analysis results.