The Analysis Of Distortion,Shear-Lag Effect And Reliability For Thin-Walled Box Girders

This dissertation analyzes the distortion, shear-lag effect and reliability for thin-walled box girders based on the theories of thin-walled bar, the random fields, the stochastic variational principle, Monte Carlo method, etc. The one-dimensional discretized finite element computational models are established for box girders with closed profiles whenever the assumption of unyielding profile is adopted or violated. Meanwhile, the effect of distortion is analyzed for box girder. The stochastic numerical methods for thin-walled box girders are studied systematically. The one-dimensional stochastic finite element method and Monte Carlo method for box girders is proposed. The main contributions of the thesis are as follows:1. Based on the symposium of unyielding profile, the one-dimensional discretized finite element methods are presented to analyse the effects of shear lag and distortion on thin-walled box girders under restrained torsion.2. On the other hand, the one-dimensional computation model is also presented for thin-walled bars with closed cross section when the assumption of unyielding profile is violated.3. Several examples are considered to illustrate the correctness and applicability of the methods presented in this dissertation. Examples show that...