{"id":{"repo_id":"nus","oai_identifier":"oai:scholarbank.nus.edu.sg:10635/107374"},"canonical_url":"https://search.dev.ndltd.org/etd/nus/oai:scholarbank.nus.edu.sg:10635/107374","repository":{"repo_id":"nus","name":"National University of Singapore","base_url":"https://scholarbank.nus.edu.sg/oai/request"},"display":{"title":"Overtrawlability and Mechanical Damage of Pipe-in-Pipe","abstract":"Pipe-in-pipes are widely used in the offshore industry. Traditionally, mechanical design of these systems with regards to fishing gear interaction has used the same approach as for single pipe systems. However, this approach is likely to result in a conservative design as the outer pipe is not required to resist internal pressure and can accommodate a greater level of indentation than a single, pressure containing pipe. Eliminating conservatism in this aspect of design has the potential to eliminate the need for trenching in areas of high fishing activity and can therefore have considerable economic benefits. The objective of this research is to develop the methods to estimate the overtrawlability of pipe-in-pipes, meanwhile review the existing methods for single wall pipes. Experiments are conducted, and FE models and semi-empirical relationships are developed and validated. The model test and scaling law are reviewed and improved.","abstract_html":"Pipe-in-pipes are widely used in the offshore industry. Traditionally, mechanical design of these systems with regards to fishing gear interaction has used the same approach as for single pipe systems. However, this approach is likely to result in a conservative design as the outer pipe is not required to resist internal pressure and can accommodate a greater level of indentation than a single, pressure containing pipe. Eliminating conservatism in this aspect of design has the potential to eliminate the need for trenching in areas of high fishing activity and can therefore have considerable economic benefits. The objective of this research is to develop the methods to estimate the overtrawlability of pipe-in-pipes, meanwhile review the existing methods for single wall pipes. Experiments are conducted, and FE models and semi-empirical relationships are developed and validated. The model test and scaling law are reviewed and improved.","abstract_has_math":false,"creators":["ZHENG JIEXIN"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-03-31","date_published":"2014-03-31","updated_at":"2026-07-24T03:32:18Z","subjects":["Overtrawlability;Pipe-in-Pipe;Indentation;Pull-over;Model Test;Scaling Law"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["ZHENG JIEXIN"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2014-03-31"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://scholarbank.nus.edu.sg/handle/10635/107374"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Overtrawlability;Pipe-in-Pipe;Indentation;Pull-over;Model Test;Scaling Law"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://scholarbank.nus.edu.sg/bitstreams/618d77c2-4686-4c06-a6bb-f563bf1f8f46/download"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Pipe-in-pipes are widely used in the offshore industry. Traditionally, mechanical design of these systems with regards to fishing gear interaction has used the same approach as for single pipe systems. However, this approach is likely to result in a conservative design as the outer pipe is not required to resist internal pressure and can accommodate a greater level of indentation than a single, pressure containing pipe. Eliminating conservatism in this aspect of design has the potential to eliminate the need for trenching in areas of high fishing activity and can therefore have considerable economic benefits. The objective of this research is to develop the methods to estimate the overtrawlability of pipe-in-pipes, meanwhile review the existing methods for single wall pipes. Experiments are conducted, and FE models and semi-empirical relationships are developed and validated. The model test and scaling law are reviewed and improved."]},{"key":"dc:format.checksum.md5","label":"Dc Format Checksum Md5","values":["c69e7a5d885922c36871f3a0660d976d","debbf8adb3e1c8b340fc439c2a5fc99d"]},{"key":"dc:title","label":"Title","values":["Overtrawlability and Mechanical Damage of Pipe-in-Pipe"]}]}],"canonical_facts":{"dc:creator":["ZHENG JIEXIN"],"dc:date.issued":["2014-03-31"],"dc:description.abstract":["Pipe-in-pipes are widely used in the offshore industry. Traditionally, mechanical design of these systems with regards to fishing gear interaction has used the same approach as for single pipe systems. However, this approach is likely to result in a conservative design as the outer pipe is not required to resist internal pressure and can accommodate a greater level of indentation than a single, pressure containing pipe. Eliminating conservatism in this aspect of design has the potential to eliminate the need for trenching in areas of high fishing activity and can therefore have considerable economic benefits. The objective of this research is to develop the methods to estimate the overtrawlability of pipe-in-pipes, meanwhile review the existing methods for single wall pipes. Experiments are conducted, and FE models and semi-empirical relationships are developed and validated. The model test and scaling law are reviewed and improved."],"dc:format.checksum.md5":["c69e7a5d885922c36871f3a0660d976d","debbf8adb3e1c8b340fc439c2a5fc99d"],"dc:identifier.uri":["https://scholarbank.nus.edu.sg/bitstreams/618d77c2-4686-4c06-a6bb-f563bf1f8f46/download"],"dc:relation.isreferencedby":["https://scholarbank.nus.edu.sg/handle/10635/107374"],"dc:subject":["Overtrawlability;Pipe-in-Pipe;Indentation;Pull-over;Model Test;Scaling Law"],"dc:title":["Overtrawlability and Mechanical Damage of Pipe-in-Pipe"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T03:32:18Z"}