Preliminary design assessment of an alternative repair method for corroded shear panels in ship hull structures

摘要

Thickness wastage due to corrosion is a typical consequence of steel plated structures that operate in a sea environment. Corrosion below a given threshold calls for the performance of rehabilitation actions in order to avoid local structural instabilities. An innovative repair technique that is based on the application of composite stiffeners in ship plated structures is evaluated numerically and at a preliminry basis. The stiffeners act as means for strengthening the plating against budding. The adequacy of the new repair design is evaluated with particular focus on a shear panel, through numerical experimentation, with regards to the required number of stiffeners, their cross section, their material and their length. Methods sourcing from Design of Experiments (DoE) have been employed. Initially a Full Factorial analysis (2(k)) has been performed so as to identify the significant design variables. In the following, a procedure based on Response Surface Methodology (RSM) and Central Composite Design (CCD) has been developed for deducing the feasible design space with repair solutions that satisfy the imposed requirements. In the practical range of the design variables, the performed study has provided initial findings which show the effectiveness of the proposed method. Depending on the design criteria and requirements imposed by the engineer, different design points may be found through the application of optimization techniques.