401 research outputs found
Application of advanced notch stress approaches to assess fatigue strength of ship structural details: literature review.
No full textThis report summarizes the literature review carried out at the beginning of the research programme in
compliance with Task 1 of the research project proposed to and funded by the A. Von Humboldt Stiftung.
Conclusions of the present report address the future steps to be undertaken in the research programe that implies exchange periods of the Author at the Hamburg University of technology.
Application of advanced notch stress approaches to assess fatigue strength of ship structural details: analysis of tests and evaluation of approaches for complex geometries
No full textThis report summarizes research activities carried out in compliance with the extension period of the research project proposed to and funded by the A. Von Humboldt Stiftung. Outline of the activities is reported in the work plan for the fourth period of exchange of the fellowship (extension) of the first author, at the beginning of the present report. Reference is made to previous reports describing activities of former periods.
Thereafter, activities are outlined as they were carried out during the stay in Hamburg of the first author.
Similarly to previous reports, this report is co-authored by Dipl.-Ing. Claas Fischer, actually Doktorand at TUHH and working on similar topics, as the reported research activities were carried out in strict cooperation
Application of advanced notch stress approaches to assess fatigue strength of ship structural details: benchmarks on complex geometries and laboratory tests
No full textThis report summarizes research activities carried out in compliance with Task #3, #4 and #5 of the research project proposed to and funded by the A. Von Humboldt Stiftung. Outline of the activities is reported in the work plan for the third period of exchange of the fellowship of the first author at the beginning of the present report, briefly summarizing the findings from the previous work and looking forward to future developments.
Thereafter, activities are outlined as they were carried out during the stay in Hamburg of the first author. Advices for future activities are also provided for both, numerical and experimental analyses. Updating of literature review about N-SIF based approaches is finally reported.
Similarly to a previous report, this report is co-authored by Dipl.-Ing. Claas Fischer, actually doktorand at TUHH and working on similar topics, as the reported research activities were carried out in strict cooperation
Application of advanced notch stress approaches to assess fatigue strength of ship structural details: consolidation and dissemination of results
No full textThis report summarizes research activities carried out in compliance with the extension period of the research project proposed to and funded by the A. Von Humboldt Stiftung. Outline of the activities is reported in the work plan for the fifth period of exchange of the fellowship (extension) of the first author, at the beginning of the present report. Reference is made to previous reports describing activities of former periods.
Thereafter, activities are outlined as they were carried out during the stay in Hamburg of the first author.
Similarly to previous reports, this report is co-authored by Dipl.-Ing. Claas Fischer, actually Doktorand at TUHH and working on similar topics, as the reported research activities were carried out in strict cooperation
A critical comparison of the scantling rules for shipbuilding issued by classification societies
No full textThe present research work starts from the working experience of the Author as field surveyor to a classification society. The rules are the link between theory and practice, between research and in service experience.
This role is of paramount importance: on a side, theory allows to develop mathematical models and design methods more and more accurate; on the other side experimental validation is always necessary.
In the last years the classification societies rules, especially the structural design rules, have been deeply and innovatively improved and probably the updating process is not completed at all.
The first chapter of this work summarizes the hystorical origin of rules and introduces reasons which imposed an evolution, undoubtedly very important for the shipping.
After a brief description describing, even from the theoretical point of view, new concepts on which new rules are based on, it seemed appropriate a comparison among the rules of the main classification societies involving both methods criteria and numerical examples.
The aim is to evaluate the impact of the rules modifications and to give a state of the art review. This choice revealed even more correct considering that in these months the main class societies are proposing the edition of common rules for ships construction, unconceivable since few years ago.
In particular the formulations for structural scantling of ABS, BV, DNV, GL, RINA and, for fatigue checks, also of CCS and NKK, have been compared.
After the theoretical analysis presented in chapter 3, some numerical examples are variously examined. They allow to highlight different aspects of the changing and to outline what can be still improved:
1. the midship section scantling of a double hull oil tanker has been scantled according to the old and the new edition of RINA rules,
2. the midship section scantling of three typical ships (a double hull oil tanker, a bulk carrier, a container ship) have been evaluated according to some rules and then results compared and analyzed,
3. a practical design example is presented regarding the lengthening of a chemical tanker according to some classification societies rules,
4. the fatigue checks of a typical detail according to different rules are presented and deeply analyzed,
5. the ultimate strength of the hull girder required by BV and RINA is compared to simplified analytical methods and with an FE model.
The last chapter addresses recommendation for further research and conclusion issues
The lengthening of al small chemical tanker: a comparison of scantling rules
No full textThe classification societies’ rules have been updated and improved dramatically in the last
years, crossing from empirically-based and prescriptive rules to more rational rules based on reliability
analyses and recommending design criteria rather than codifying design scantlings. However, the
complexity of the new rules needs to be faced by computer software issued by the class societies
themselves. This article presents the results of some preliminary structural design calculations, carried
out according to five different classification societies’ rules (BV, DnV, GL, LR and RINA) and using
the associated softwares, on a small double hull tanker built in the nineties. In view of the possible
lengthening of the ship, the scantling design has been carried out on the midship section, aiming to
compare the different rules, requirements and criteria before and after lengthening. An analysis of
general check formulations has been firstly carried out, highlighting similarities and differences in the
scantling criteria. Then, results of the exercise have been compared to evaluate the best solution for
lengthening, and rules requirements have been commented on in the light of the methods and criteria
previously reported with the aim to contribute to the rules harmonization process
Fatigue life of typical welded joints by fracture mechanics approach and reliability analysis
No full textEditorial Special Issue on Passenger Ships and Yachts
No full textPresentatio of the paper of the Special Issu
- …
