Collapse strength of hatch cover of bulk carrier subjected to lateral pressure load

A series of elastoplastic large deflection FEM analyses has been performed on hatch covers of bulk carriers subjected to lateral load. Two types of hatch covers are considered which are the folding type and the side-sliding type. For the folding-type cover, one size is considered which is for Handy size bulk carrier, whilst for the side-sliding-type cover, two sizes are considered which are for Panamax and Cape size bulk carriers. For each type, two hatch covers are selected which are designed in accordance with the old ICLL rule and new IACS rule, respectively. Calculated collapse strengths are compared with individual design loads, and a strength assessment is performed. On the basis of collapse behaviour observed in FEM analyses, a simple method is proposed to evaluate the collapse strength of a hatch cover subjected to lateral load. It is confirmed that the collapse strength is accurately predicted by the proposed method.     

论PSSA的发展及对我国建立PSSA的思考

随着不断增长的船舶交通量和危险货物的运输,对海洋环境潜在威胁的加大和大众对海洋环境保护意识的不断增强,指定和实施特别敏感海域已成为越来越多国家防止海洋污染的政策之一。然而,作为一种需要实施特殊环境保护的海域,特别敏感海域的指定目前在IMO引起了非常激烈的讨论。本文主要介绍了PSSA的发展历程及其热点问题,并阐述了对我国建立PSSA的一些想法。     

Fatigue crack propagation and computational remaining life assessment of ship structures

The fitness for serviceability of structural members of marine structures in which fatigue cracks might be found during in-service inspection is investigated in order to prevent instantaneous failures of ships, as well as a loss of serviceability such as the oil- and/or watertightness of critical compartments. The essential features of fatigue crack propagation and the remaining life assessment are discussed in the first part of the paper, where the effects of weldment, complicated stress distributions including stress biaxialities at three-dimensional structural joints, structural redundancy, and crack curving are found to be of primary importance. The second part of the paper contains a discussion of an advanced numerical simulation method for the remaining life assessment, in which the above-mentioned effects of fatigue crack propagation are taken into account. The simulated crack paths and the fatigue crack propagation lives are found to be in fairly good agreement with the experimental results.     

水利工程中进度控制的风险评估

分析影响施工进度的因素，并以施工方因素为例建立模糊风险评价集。利用模糊综合评价法对水利工程中影响施工进度的因素进行定量的风险评估，得出施工方各因素对施工进度影响的定量值，可以达到有效减小风险的效果。     

Collision damage of jack-ups

North Sea collision accident records covering a period of ten years indicate that the risk of collisions involving jack-ups is not dissimilar to that for semi-submersibles or fixed jacket structures. However, jack-ups are much more flexible than jackets and have a much lower degree of redundancy. Their response to collisions and their ability to absorb impact energy is, therefore, expected to be considerably different in comparison to jackets. This paper examines available data and information regarding the capability of jack-ups to withstand collision impacts and investigates the level of local damage that can potentially be caused to jack-up legs due to accidental collisions.     

Risk assessment for fire safety considering characteristic evacuees and smoke movement in marine fires

In the safety design of marine systems, the matter of human life in the event of a marine fire must be considered. It may be difficult to establish a safe evacuation system because a characteristic behavioral pattern based on human factors is elusive. This study consists of three analyses on (1) the state of smoke diffusion, calculated by the use of a two-layer zone model, (2) evacuation movements, simulated by a group behavioral model, and considering the occurrence of panic and the smoke spreading phase, and (3) the risk index for safety assessment using the results of smoke diffusion and escape movements. This risk index can be used for comparisons between various safety systems, and its validity is confirmed by an evacuation model of common spaces on a typical cruise ship.     

关于铁路隧道风险评估方法的探讨

开展铁路隧道风险评估，有利于决策科学化，有利于减少工程事故的发生，有利于提高政府、业主、设计单位和施工单位的风险管理意识和风险管理能力，从而达到控制风险、减少损失的目的。此文主要针对铁路隧道风险评估的方法进行探讨，供有关设计、施工和建设管理人员参考。     

5800DWT杂货船总体和结构设计的特点

本文介绍了5800DWT杂货船总体和结构设计的特点，可供同类型船设计、研究参考。     

高速公路贷车计重收费标准构建与方案优化研究

系统研究了如何以原分型收费标准和载货车辆质量分布为依据构建货车完全计重收费标准,并且研究了计重收费标准的评价指标和优化方法。最后以天津市为例,给出了应用本文方法所生成的两个计重收费标准方案。     

电力机车牵引绕组阻尼电路参数匹配对设备安全的影响

根据整流桥换流工作原理,研究了绕组阻尼电路的工作特点,给出阻尼电容电流及电阻功耗的计算方法,通过计算分析找出阻尼器件大量损坏的原因;分析了阻尼电容放电电流对晶闸管的危害性;进一步探讨机车操作过电压特点,推荐能兼顾操作过电压、满足阻尼器件和整流装置安全工作的阻尼电路参数。