基于不同概率分位值的荷载特征值取值方法及其比较

在对荷载概率分布模型分析的基础上,采用伯努利试验假设,建立了任意设计基准期内的荷载概率分布模型,提出基于“基准点法”的荷载特征值取值标准,即取设计基准期内荷载极大值分布的概率密度函数最大的荷载作为特征值,并进一步导出了与设计基准期对应的荷载特征值计算公式和表格。采用“基准点法”可以方便求得与设计基准期直接对应的荷载特征值,避免了按“重现期法”计算得到的荷载特征值在设计基准期内的保证概率随设计基准期的缩短而降低的问题,使荷载具有与设计基准期无关且更为安全的统一保证概率。

Method and comparison of characteristic value of loads with different probabilities

The probability distribution model of load in an arbitrary design reference period is established based on Bernoulli trials model by analyzing the probability distribution model of loads in the paper.The calculation method of characteristic value of load is put forward on "the referential point method" by which computation formulas and tables of characteristic value of load corresponding to the design reference period are given.It is avoided that the guarantee probability in the design reference period degrades while the design reference period reduces is avoided by adoption of "the referential point method".The method presented in the paper is more practical to structure design of civil buildings that has a relatively short design reference period.