矿砂船舱口间甲板结构的可靠性评估

文章针对一艘舱口间甲板发生屈曲破坏的矿砂船,对其舱口间甲板结构进行横向压缩强度分析和可靠性评估。为建立一套初步的可靠性评估方法,首先,采用半解析公式计算舱口间甲板结构在不同破坏模式下的压缩极限强度,其最小值即为结构的临界应力,为强度评估提供依据。其次,基于改进的一次二阶矩法编写FOR?TRAN子程序,计算结构的可靠性指标,建立了基于舱口间甲板的横向压缩强度的可靠性分析程序。综合评估结果表明,舱口间甲板结构的强度储备不足以抵抗外部载荷,屈曲破坏发生起始于檐板和舱口间甲板,这与目标船的事故分析报告中的屈曲现象吻合。根据舱口间甲板结构的强度和可靠性评估结果,采取三种加强方案,权衡结构安全因子和结构重量从而得出较优的修复加强方案。

Structural reliability assessment on cross-deck structures of ore carrier

This paper concentrates on transverse compressive strength and structural reliability assessment of the cross-deck structures of an ore carrier in which buckling damages were found on the cross-deck strip plating and stiffeners.To develop a structural reliability-based procedure for the preliminary analysis,the minimum value from the ultimate strength at different collapse modes of the structures is firstly selected as critical stress by analytical approaches to provide criteria for the strength assessment.The FORTRAN subroutines for reliability procedure is written based on the advanced first-order second-moment method to analyze the structural reliability indies.It can be concluded that the cross-deck structures are not strong enough to resist the loads and the buckling initiation is identified at curtain plate and upper deck,according with the phenomena on the damaged ore carrier.Consequently,three strengthening methods are implemented by comparing the factors of safety and structural weight to explore a more optimal repaired option of cross-deck structures on the basis of the assessment results.