Improvement of trawler hull structure under condition of ensuring fatigue strength

The structure of the hull project 1288 trawler in a region fore hold was improved to ensure fatigue strength assemblies intersection main frames with second bottom. To this end, study these carried out for original side and two versions its modernization. Values internal forces at points appearance cracks compartment have been determined three design side. It found that greatest act middle half compartment. Calculations parameters long-term distribution magnitudes ranges total equivalent operating stresses according Weibull law occurrence different grillage performed. These were vessel areas which maximum values bending moment are effect without corrosive wear. damage durability studied determined. by nominal stress method, hot spot experimental theoretical method. shown order assembly under consideration, it is necessary extend intermediate version level bottom fixing them deck. also attach cargo platform thus reducing frame span. As result, over 25 years operation will decrease about 3.5 times. found, approximate consideration slamming does not significantly increase amount assembly. results development recommendations modernization can be implemented both on ships other transverse framing system.