分项系数与目标可靠指标的关系及其应用-《高速铁路技术》

文章信息/Info

Title:: Relationship between Partial Factor and Reliability Index and Its Application

Author(s):: LUO Yinong; WANG Zhansheng; GUO Haiqiang; China Railway Eryuan Engineering Group Co., Ltd., Chengdu 610031, China

Keywords:: reliability design standard (code)|reliability index|partial factor|railway engineering

摘要:: 本文从可靠指标与分项系数的概念和数学含义出发，分析了分项系数与可靠指标的关系；归纳总结了分项系数和目标可靠指标在工程设计中的应用；提出了在《工程结构可靠性设计统一标准》（第一层次标准）和《铁路工程结构可靠性设计统一标准》（第二层次标准）中应明确分项系数和可靠指标的对应关系，以及在结构或构件的极限状态设计规范（第三层次规范）中分项系数和目标可靠指标的作用，以指导规范的编制和工程设计。研究的结论：（1）分项系数与可靠指标正相关应满足一定的条件；（2）可靠性设计统一标准中可靠指标和分项系数计算公式应给出适用条件并补充完善，才能消除由于相关性带来的误差；（3）工程设计规范应给出分项系数，可给出对应的目标可靠指标；（4）在实际工程设计中，建议特殊设计采用可靠指标进行设计，常规设计采用分项系数进行设计。

Abstract:: Based on the concepts and math meanings of reliability index and partial factor, the relationship between reliability index and partial safety factor is analyzed, and applications of them in engineering design are concluded. It is necessary to clarify the relationship between reliability index and partial safety factor in Unified Standard for Reliability Design of Engineering Structures (the first level) and Unified Standard for Reliability Design of Railway Engineering (the second level), as well as the functions of them in design code of ultimate state of structures or components (the third level) to guide the compilation of codes and engineering design. Study result:(1) Reliability index and partial safety factor are positively correlated under certain conditions; (2) Application conditions should be given for calculation formula of reliability index and partial factor in the unified standard of reliable design to eliminate errors due to correlation; (3) Partial factor should be given for engineering design code, and corresponding reliability index can be given; (4) In the actual engineering design, it is better to adopt reliability index for irregular design, By contrast, it is better to adopt partial factor for conventional design.