42000吨散货船结构疲劳可靠性评估

STRUCTURE FATIGUE RELIABILITY ASSESSMENT OF 42000 DWT BULK CARRIER

本文从可靠性概念出发，对沪东造船厂建造的42000吨散货船甲板角隅结构疲劳强度进行安全评估。评估中考虑了疲劳数据的离散性、应力分析的误差以及波浪载荷的随机性等不确定因素，结果表明，该船甲板角隅的疲劳可靠性水平在0．98以上，即失效概率小于0．02，较好地反映了该船的实际情况。该评估方法也可用于集装箱船甲板大开口疲劳安全评估。选择合适的可靠性水平，保证角隅恰当的疲劳强度，避免角隅疲劳裂纹的产生，对集装箱船结构安全具有实际意义。

The safety assessment of a 42000 DWT bulk carrier, built by Hudong Shipyard, iscarried out in aspect to structure fatigue from viewpoint of reliability. In the analysis,such uncertainities are considered as scatter in fatigue data, quality of fabrication andworkmanship, error in stress analysis, and variable loading, etc. The results indicate thatthe fatigue reliability level of hatch corner of the 42000 DWT bulk carrier is above 0. 98,that is, probability of failure is less than 0. 02, which is in accord with practical situationof the ship to great extent. This assessment approach may also be used to container shipswith large openings on deck. Anadequate reliability level should be chosen to guaranteesuitable fatigue strength and prevent from generation of fatigue cracks, which has greatpractical value for structure safety of container ships.