钢桥构件焊接残余应力的有限元分析-结构工程专业论文.docxVIP

ABSTRACT Welding is the principal way of connection in building steel structures, which is applied to steel bridges more and more widely in recent years. In the process of welding, due to phase change of material, displacement constraints, uneven distribution of temperature field etc, residual stress and deformation are formed in the components , which affect the initiation and propagation of cracks in welding structure and reduce the mechanical properties of steel substantially. Based on temperature - structure coupling function of the general finite element software ABAQUS, utilizing subroutine DFLUX to simulate welding heat source, welding residual stress and deformation of the important components of a steel bridge are analyzed, then patterns of production and distribution of residual stress and deformation can be obtained, which provides important basis for controlling and reducing the residual stress in construction with effective measures. The main contents of the paper are showed as follows: This paper introduces the basic theory and commonly used methods of numerical simulation of welding residual stress, and how to measure and eliminate welding residual stress effectively. In addition, the key technologies in simulation of welding process using ABAQUS are discussed in this paper. Due to high bearing capacity and stiffness, steel saving and the obvious economic benefit, the corrugated web is widely used in the areas of bridge. In this paper welding temperature field, distribution of residual stress and deformation of three kinds of H-beam with different shapes of corrugated web, including sawtoothed, trapezoidal and sinusoid, are studied. The residual stress of U-shaped stiffener in Haihe bridge and L-shaped stiffener in Haimen bridge in the manufacturing process are analyzed to acquire initial stress for the analysis of the whole bridge, and study the influence of welding residual stress Taking Chunyi bridge in Tianjin as the research background, residual