在LNG液舱建造中，围护系统受到脚手架垫块的垂向压缩载荷作用，垫块压力需控制在限值内以避免损坏围护系统。以Mark III型薄膜围护系统为研究对象，基于抗压试验结果开展非线性有限元计算，验证相关参数设置的合理性；总结围护系统关键失效模式，建立基于许用应力的抗压承载能力判定方法；调整设计参数分析围护系统抗压承载能力主要影响因素，探讨结构薄弱环节。阐明垫块作用面积、树脂绳间距与宽度、底层合板厚度及泡沫密度对抗压承载能力的影响，根据最优设计参数判定准则选定设计参数，围护系统临界承载能力提升22.7%。通过改善底层合板受力，可有效提升围护系统抗压能力，研究成果可为新型围护系统设计与建造过程中的安全评估提供参考。
During the construction of liquefied natural gas (LNG) tanks, the cargo containment system (CCS) is subjected to vertical compressive loads from scaffolding pads, and the pad pressures need to be controlled within limits to avoid damage to the CCS. The Mark III type thin-film CCS was selected as the research object. Based on the compression test results, nonlinear finite element calculations are performed to verify the reasonableness of the relevant parameter settings; the key failure modes of the CCS are summarized, and a method for determining the compressive capacity based on the allowable stress is established. The design parameters are adjusted to analyze the main factors influencing the compressive capacity of the CCS and to investigate the structural weaknesses. The effects of pad area, mastic rope spacing and width, back plywood thickness, and foam density on the compressive capacity were elucidated. The design parameters were selected according to the optimal design parameter determination criterion, and the critical bearing capacity of the CCS was increased by 22.7%. By improving the strength of the back plywood, the compressive capacity of the CCS can be effectively improved. The research results can provide a reference for safety assessment in the design and construction of new cargo containment systems.
2025,47(16): 38-45 收稿日期：2024-12-3
DOI：10.3404/j.issn.1672-7649.2025.16.007
分类号：U671.42
基金项目：国家自然科学基金资助项目（52175239, U2241266, 51979163）
作者简介：高大威(1979-),女,博士,教授,研究方向为结构安全优化设计
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