The Analysis Of Test Method Of Welding Residual Stress In Steel Structure

With the development of production and scientific and technological progress, welding technology has been widely used in bridges, buildings and other fields, the development of the national economy plays a very important role. Because of the high concentration of transient heat input, component weld will have a considerable welding residual stress and deformation, which will have a variety of mechanical properties of welded joints have different degrees. The existence of welding residual stress, on the one hand reduce the strength of the workpiece, so that generated when the workpiece during the manufacturing process defects such as deformation and cracking; the other hand, will naturally release later in the manufacturing process, to change the size of the workpiece, or to fatigue , stress corrosion and other mechanical properties decrease. Therefore, the residual stress measurements, to ensure the safety and reliability of the workpiece has a very important significance.At the same time, the method of welding residual stress can be more accurate grasp of welding residual stress component size and distribution, the study of welding residual stress distribution has important significance.The author access to a large number of relevant information, based on the basic theory of welding, welding residual stress of the formation mechanism were consolidated, summed up and concluded, and on this basis, detailed residual stress present some of the more common method of testing and describes the current residual stress at home and abroad a number of new testing methods, in this based on the development trend of residual stress were analyzed. And made a rational choice to the appropriate residual stress testing methods.This article relies on the Yangtze River Bridge in Chongqing Jiangjin guanyinyan pieces welded plate tests, using magnetic components measured by ultrasound determination of residual stress before and after the impact of component received test data applications of mathematical statistics in line with the theoretical analysis and proof of Central Limit Theorem, hypothesis testing experimental data have lent their sequence of distribution functions converges to normal distribution, analysis of test data derived welding statistical analysis to meet the requirements for component design and master the changes in weld stress provide some guidance.