摘要
在大坝的长期使用过程中,影响其防洪安全的许多不确定性因素具有明显的时变特性。本文分析了大坝的防洪随机时变特性,论证了缓变性和陡变性作用对大坝防洪安全的影响都极为显著。将非平稳的时变随机过程进行平稳化处理,建立了时变随机量量化的单因子函数模型和多因子综合模型。在此基础上,拓展了风险率的概念,将时变效应引入大坝工程老化的研究中,给出了大坝防洪时变风险率的计算公式。以某水库调洪能力的时变效应分析为例,定量评估了水库库容和坝顶高程的时变特性,讨论了其对大坝防洪风险率的影响,实现了对大坝设计基准期内防洪安全性的定量评估。
In the process of long-term operation of dams, various uncertain factors having negative impact on the flood control safety are of obvious time-varying characteristics. In this paper, the time-varying characteristics of flood control of dams due to this effect both the impact of mild procedure and abrupt change are demonstrated. Through the treatment of unsteady time-varying stochastic process, a functional model of time-varying stochastic factors are established. On this process with a single factor and basis, the concept of risk rate is a comprehensive model with various extended. The time-varying effect is then introduced into the study on dam ageing problem. An equation for calculating time-varying risk rate of dams is proposed. The time-varying effect of the flood regulation capacity of a typical dam is given as an example to demonstrate how to quantitatively assessing the time-varying characteristics of the storage capacity of the reservoir and the elevation of the top of the dam. The influence on flood control risk rate is also discussed.
出处
《水利学报》
EI
CSCD
北大核心
2006年第4期425-430,共6页
Journal of Hydraulic Engineering
基金
国家自然科学基金资助项目(50579038)
水利部科技创新项目(SCX2002-06)
关键词
时变效应
时变风险
防洪安全评估
大坝老化
time-varying effect
risk rate
assessment of flood control safety
dam ageing
