Effect of weld geometry parameters on dynamic behavior of buried X70 steel pipeline under subsurface detonation

Abstract

Although a significant amount of research has been conducted to investigate the deformation and failure of buried pipelines subjected to load disturbance, scarce information is available about the effect of weld geometry parameters on the dynamic behavior of buried pipelines under blast loads. In the present study, numerical method and range analysis method were conducted to investigate the effect of weld geometry parameters including bevel angle, residual weld height, weld root opening, and thickness of root face on the dynamic performance of welded X70 steel pipelines under subsurface detonation. The results showed that the deformation of explosion-front surface is larger than that of explosion-back surface of the buried pipeline. The bevel angle, residual weld height, and thickness of root face have different effects on the dynamic comparison index of the welded pipes including peak vibration velocity, peak equivalent stress, peak equivalent strain, and peak displacement. Reasonable configuration should be adopted to properly select the geometry and dimensions of welding groove due to the complex influence of the weld geometry parameters. Combined the present results with the designing practice and current standards, the suggested weld geometry parameters to decrease their effects on the dynamic behavior of the welded X70 steel pipeline are as follows: the bevel angle (25 ± 5°), residual weld height (less than 1 mm), weld root opening (3.5 ± 0.5 mm), and thickness of root face (1.6 ± 0.6 mm).