关键词: R/S分析, PSO-BP神经网络, 趋势判断, 隧道变形

Abstract: In order to judge the tunnel deformation trend accurately, scientifically and comprehensively, the monitoring period of the tunnel is divided into medium-term stage and long-term stage, then rescaled range analysis (R/S) is used to judge the displacement sequence and the rate sequence. PSO-BP neural network is applied to predict the deformation in each stage, and the forecast results are compared with the R/S analysis results to verify their consistency. The test results of two engineering examples show that Hurst index of each sequence is greater than 0.5, indicating each sequence has a long and sustained deformation, and the tendency of displacement sequence is greater than that of the rate sequence. The prediction result illustrates that the tunnel deformation would continue, which verifies the accuracy of R/S analysis.

Key words: R/S analysis, PSO - BP neural network, deformation trend judgment, tunnel deformation