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101.
In this paper the structural system reliability method is applied to a built SWATH ship. Firstly, a typical transverse frame in the SWATH is idealized by a one-dimensional model through a series of finite element analyses. The safety margins are automatically generated by computer and the interaction of bending moment and axial force, including buckling effect, is taken into account. The significant failure modes of the structure are identified by an extended β-unzipping method, and the system reliability index is then evaluated by Ditlevsen's bounds. It is found that the most critical section is in the haunch area, and all the critical sections included in the significant failure paths are in the haunch area. 相似文献
102.
Civil infrastructure facilities play a central role in the economic, social and political health of modern society. Such facilities are susceptible to ageing, which is stochastic in nature and makes their reliabilities time dependent. Life-cycle engineering analysis and risk-informed decision tools have advanced in recent years for managing public investments in performance assurance and risk mitigation of civil infrastructure. However, certain civil infrastructure projects may be designed for service periods that are substantially longer than what has been typically expected of buildings, bridges and similar facilities, extending the potential consequences of life-cycle engineering decisions far beyond the limits for which there is practical experience. Current assessment procedures will require modification to evaluate performance of civil infrastructure facilities over extended time frames and to support sustainable and equitable decisions affecting long-term public safety. This paper considers a number of key issues that must be addressed in life-cycle reliability assessment of civil infrastructure facilities that must remain functional for service periods of several generations, and introduces perspectives on risk that are germane to ensure sustainability and intergenerational equity in risk-informed decision-making. 相似文献
103.
通过对二级供水泵站多年的管理与总结,从影响供水系统可靠性的诸多因素,保障供水系统可靠性的各种方法等方面进行了分析,提出了应采用科学的管理方法来解决大型企业吃水难的问题。 相似文献
104.
采用可靠度分析的蒙特卡罗法 ,建立了加筋土边坡稳定极限状态方程 ,对其可靠度进行了分析 ,并结合工程事例 ,讨论了土性参数的均值和变异系数对可靠度指标的不同影响 ,指出可靠指标度量加筋土边坡稳定性更合理。 相似文献
105.
通过拓扑学的网络分析方法,从建筑路径的整体性特征人手,建立了以结点、弧段为基本构成要素的拓扑路径网络。提出了路径网络的平面嵌入定理,立体状网络转换方法,以及立体网络的判断问题。并分别对路网的结构、路径的可靠性、可达性、可贯穿性进行阐述。力求利用拓扑学原理解决一些建筑路径的设计中所遇到的问题,从而为路径设计和真实地构建路径奠定了基础。 相似文献
106.
花岗岩残积土边坡稳定性可靠度分析 总被引:2,自引:0,他引:2
运用工程上广泛采用的简化Bishop法建立极限状态方程,考虑容重、粘聚力和内摩擦角为随机变量,利用简洁实用的优化方法求解边坡的可靠度指标,并利用Excel中的规划求解工具进行求解,避免了正交变换和极限状态方程求偏导数的问题。针对福建省花岗岩砂质粘性土边坡进行可靠度分析,比较土性参数不相关与相关情况下的研究结果,说明边坡可靠度不仅与土体参数均值有关,而且与其变异系数和相关性有关,且变量的相关性对可靠度有较大影响。因此,边坡用传统安全系数法分析是稳定时,也存在失稳的可能。 相似文献
107.
介绍了美国当前在纸面石膏板板面接缝处理方面的先进技术 ,如接缝材料、施工机具的类型和选择 ,接缝处理施工技术 ,施工质量通病及防治措施等。 相似文献
108.
An innovative prediction method for the combination of failure modes of an arch bridge is proposed for its probabilistic risk assessment and is compared with the conventional system reliability analysis method. The suggested method reveals various combinations of failure modes in significantly reduced time and efforts in comparison to the previous permutation method or the conventional system reliability analysis method. Additionally, the suggested method can be used for the verification of the system reliability with more specific predictions of the failure modes.Component reliabilities of girders have been evaluated by using response surfaces of the design variables at the selected critical sections, i.e. the maximum shear and negative moment locations. Response Surface Method (RSM) is successfully applied for the reliability analyses of complex structure with relatively small probability of failure. Previous methods such as Monte Carlo Simulations or First Order Second Moment method cannot easily calculate the derivative terms of implicit limit state functions. Hence, the target bridge system is modeled as a series-connection system for the analysis of its system reliability. The upper and lower bound of the probabilities of failure for the structural system have been evaluated and are compared with the suggested prediction method for all possible combination of failure modes. 相似文献
109.
110.