Analysis And Experimental Research On Grouting Sleeve Reinforcement Of Jacket Partial Severely Damage

Jacket is an important supporting structure of offshore platforms,and its reliability is a prerequisite for ensuring the safety of offshore oil and gas platform personnel and the normal operation of the platform.However,jackets in the complex and harsh marine environment are often partially damaged due to various reasons.Based on the research on the structural characteristics and connection forms of various connecting sleeves at home and abroad,this paper proposes a grouting sleeve with built-in wedge teeth to realize the connection and repair of partially large defects or even partially broken jackets.The characteristic of this new type of sleeve is that its connection bearing capacity is provided by the built-in wedge teeth and the expansion clamping force of the injected grout.Therefore,compared with ordinary grouting sleeves,its bearing capacity is greatly improved.This article firstly compares and analyzes the critical buckling stress of the intact and defect-free jacket before and after the sleeve connection is reinforced,and studies the strengthening effect of the sleeve connection on the jacket.Then the mechanical clamping force of the wedge-tooth clamping grouting sleeve and the expansion clamping force of the grout are respectively analyzed.Next,the overall structure of the sleeve and the wedge tooth clamping mechanism were designed respectively.Since the grouting sleeve is subjected to ocean wave forces during operation,this article analyzes the wave loads on the grouting sleeve installed in different positions.Finally,the clamping mechanism of the wedge tooth,the tooth tip profile of the wedge tooth and the force and deformation of the triangular profile tooth tip are analyzed,and the load on the wedge tooth is optimized by cutting off the triangular tooth tip.The distribution situation improves the mechanical bearing capacity of the sleeve.In order to further study the connection and reinforcement performance of the wedge-tooth clamping grouting sleeve,this paper firstly carried out the axial loading experiment on the defect-free jacket before and after the sleeve connection and reinforcement,and compared the deformation of the jacket..Then,the axial loading experiment and the radial loading experiment were carried out on the 40 mm large-diameter defective jacket before and after the sleeve connection and reinforcement.Through the comparative analysis of the experimental data,it is found that the sleeve connection has a good reinforcement and repair effect on the complete jacket and the large-diameter defective jacket.At the same time,the reinforcement through the sleeve connection can also greatly weaken the partial defects of the jacket on the lateral load.The degree of sensitivity is conducive to the resistance of the damaged jacket to the lateral wave load.Finally,through the axial loading experiment on the two disconnected jacket specimens connected by the sleeve,the equivalent friction coefficient between the wedge teeth and the outer wall of the jacket was obtained,and the self-locking slope of the wedge teeth was obtained.Maximum inclination.