Quantitative Analysis Method of Multi-measuring Point Deformation of Concrete Dam Based on BFAST Time Series Decomposition and Subsection Modeling
The operation environment of dams is complex,and there is an obvious nonlinear relationship between the deformation and the external load.This paper presents a quantitative analysis method of concrete dam deformation at multiple measuring points based on BFAST time series decomposition and sectional modeling.Based on the vertical moni-toring data of gravity dams,principal component analysis is firstly used to extract the comprehensive displacements of multiple measuring points.Then,the BFAST time series decomposition method is used to decompose the comprehensive displacement into two parts:seasonal and trend.Finally,through the reasonable selection of change points,a segmented statistical regression model is established to quantify the impact of various environmental variables on dam displacement in different periods.The feasiblity and effectiveness of the proposed method is validated by the segmented quantitative anal-ysis of the horizontal displacement law of Ankang Hydropower Station.The research results provide strong technical sup-port for better analysis of the evolution of dam deformation behavior and quantitative interpretation of dam deformation mechanism.
BFASTtime series decompositionmutation detectiondam safety monitoringprincipal component analysis