关键词: 随机场理论, 方差折减函数, 相关函数法, 完全不相关距离

Abstract: The calculated failure probability for foundation and slope is usually very large, even though the project is proved to be safe in reality. This phenomenon is resulted mainly from the method to estimate variance in practical project. Data of soil index is just property of a certain point rather than the space average characteristic of soil profile. In the process of reliability analysis of geotechnical engineering, the reduction function of variance is the key parameter to transit the point property into spatial average property. It’s the first time that improvement on the method to calculate the no correlation distance put forward by YAN Shu-wang et al. is made, which not only makes the calculation more convenient, but also is a breakthrough of theory. The procedure of calculation of reduction function by the improved method is analyzed, and general regularity of determining reduction function through calculation of no correlation distance is obtained.

Key words: stochastic field theory, reduction function of variance, correlation function method, no correlation distance