Bridge failure, which is generally associated with serious economic and life losses, is defined as the incapacity of a constructed bridge or its components to perform as specified in the design and construction requir...Bridge failure, which is generally associated with serious economic and life losses, is defined as the incapacity of a constructed bridge or its components to perform as specified in the design and construction requirements. This paper presents an overview of current researches on the typical characteristics and causes of bridge failures based on 10 former investigations. Principal causes can be divided into internal causes and external causes or natural factors and human factors. Design error, construction mistakes, hydraulic, collision, and overload are the top 5 leading causes of bridge failures, resulting in more than70% of the bridge failures. Causes of bridge failures are closely related to regional economy,structural type, type of use, material type, and service age. The failure rate is very high for steel bridges, which is inseparable from excessive emphasis on structure strength but lack of consideration on structure stability and fatigue in early years. Researchers need to strengthen their research on the stability and fatigue of steel bridges, as well as inspection and maintenance. Extreme loads such as flood, collision, and overload contribute to a large number of bridge failures because of the lack of extreme loads data and design theory defects. It is critical for such bridges to have sufficient redundancy and capacity protection measures to reduce the probability of bridge failure due to extreme loads. Previous statistical methods and classification methods for the characteristics and causes of bridge failures lack unified standards, and a more scientific method needs to be established. A comprehensive electronic database on bridge damage and failures needs to be developed to establish damage models and conduct forensic studies to improve the design theory and specifications.展开更多
目的考察研究生内隐、外显幸福感及学业成败归因特点,进而探讨研究生学业成败归因与内隐、外显幸福感间的关系。方法采用《多维多向归因量表》(MMCS)、《幸福感指数量表》(Index of well-being)以及内隐联想测验(IAT)对64名研究生进行...目的考察研究生内隐、外显幸福感及学业成败归因特点,进而探讨研究生学业成败归因与内隐、外显幸福感间的关系。方法采用《多维多向归因量表》(MMCS)、《幸福感指数量表》(Index of well-being)以及内隐联想测验(IAT)对64名研究生进行测验。结果1外显、内隐幸福感是相对独立的结构;2研究生外显、内隐幸福感均无显著性别差异;3在进行学业成败归因时具有显著性别差异,男生较女生更容易进行内归因;4当学业失败时,外显幸福感高的人更倾向归因于情境因素(r=0.25);内隐幸福感中情感体验消极的人更倾向归因于自身能力不足(r=-0.31)。结论研究生学业成败归因与其外显、内隐幸福感存在联系。展开更多
基金funded by the Communication Research Project of Department of Transport of Shaanxi Province(19-07K)the Special Fund for Basic Scientific Research of Central College of Chang’an University(300102219310)。
文摘Bridge failure, which is generally associated with serious economic and life losses, is defined as the incapacity of a constructed bridge or its components to perform as specified in the design and construction requirements. This paper presents an overview of current researches on the typical characteristics and causes of bridge failures based on 10 former investigations. Principal causes can be divided into internal causes and external causes or natural factors and human factors. Design error, construction mistakes, hydraulic, collision, and overload are the top 5 leading causes of bridge failures, resulting in more than70% of the bridge failures. Causes of bridge failures are closely related to regional economy,structural type, type of use, material type, and service age. The failure rate is very high for steel bridges, which is inseparable from excessive emphasis on structure strength but lack of consideration on structure stability and fatigue in early years. Researchers need to strengthen their research on the stability and fatigue of steel bridges, as well as inspection and maintenance. Extreme loads such as flood, collision, and overload contribute to a large number of bridge failures because of the lack of extreme loads data and design theory defects. It is critical for such bridges to have sufficient redundancy and capacity protection measures to reduce the probability of bridge failure due to extreme loads. Previous statistical methods and classification methods for the characteristics and causes of bridge failures lack unified standards, and a more scientific method needs to be established. A comprehensive electronic database on bridge damage and failures needs to be developed to establish damage models and conduct forensic studies to improve the design theory and specifications.
文摘目的考察研究生内隐、外显幸福感及学业成败归因特点,进而探讨研究生学业成败归因与内隐、外显幸福感间的关系。方法采用《多维多向归因量表》(MMCS)、《幸福感指数量表》(Index of well-being)以及内隐联想测验(IAT)对64名研究生进行测验。结果1外显、内隐幸福感是相对独立的结构;2研究生外显、内隐幸福感均无显著性别差异;3在进行学业成败归因时具有显著性别差异,男生较女生更容易进行内归因;4当学业失败时,外显幸福感高的人更倾向归因于情境因素(r=0.25);内隐幸福感中情感体验消极的人更倾向归因于自身能力不足(r=-0.31)。结论研究生学业成败归因与其外显、内隐幸福感存在联系。
