Numerical analysis on the SIF of internal surface cracks in steel pipes reinforced with CRS subjected to bending

Abstract

In this paper, Composite Repair System (CRS) is applied to repair the circumferential internal surface cracked steel pipes subjected to bending. The Stress Intensity Factor (SIF) is quantitatively analysed by means of numerical simulations, and the crack growth rate is predicted by using the Paris' law. First, the three-dimensional finite element (FE) model is developed, and its reliability of evaluating SIF of internal surface crack in CRS reinforced pipe is validated. Then based on the FE method and combined with Paris' law, a case study is deployed to predict the internal surface crack growth in steel pipes reinforced with CRS. The results show that CRS have significantly reduced the SIF of the internal surface crack and decrease the crack growth rate, while unchanging the variation trend of the crack aspect ratio. Afterwards, a parametric study is performed in order to guide the optimisation design of CRS reinforcement.

Surface Crack Growth in Offshore Metallic Pipes under Cyclic Loads: A Literature Review

“…Maintaining the structural integrity of offshore metallic pipelines is of great importance to guarantee operational safety. While as a matter of fact, offshore metallic pipelines are prone to the fatigue problem due to a variety of environmental and operational dynamic loads [1,2]. For instance, there are two typical layouts of offshore metallic pipes: the S-shape and the J-shape (as shown in Figure 1), where the critical areas, i.e., hang-off zone, touch-down zone, sag bend, and arch bend, seriously suffer from fatigue problems under dynamic loads induced by waves, wind, currents, 2nd order floater motions, and unstable internal pressure [3,4].…”

Experimental investigation on FRP-reinforced surface cracked steel plates subjected to cyclic tension

“…They might continually propagate under cyclic loads, causing serious threats to the structural integrity. In practical situations, preventing surface cracks from propagating to through-thickness cracks is of great importance, such as in the fields of aerospace engineering [4], transportation pipelines [5,6], pressure vessels, and nuclear reactors [7,8]. Fiber-Reinforced Polymer (FRP) reinforcement is a recognized alternative of traditional fatigue crack repairing methods, such as bolting, welding, and drilling a stop hole [9][10][11][12][13].…”