Research on Early Warning Indicators of the Foundation Slope of the Hetaoshu Bridge on the Yiba Expressway

Abstract Due to the limitations of terrain and geological conditions, the bridges and tunnels of expressways in western mountainous areas are relatively high, and the number of bridge projects crossing landslide areas or unstable slopes is increasing. The deformation of the slope directly affects the stability and safety of the upper bridge structure. A 3‐year deformation monitoring and analysis work has been carried out to address the disease problem of the Hetaoshu Bridge of the Yiba Expressway. A systematic review has been conducted on the warning indicators and their thresholds for sliding slopes that have been reported in various literature. Based on the observation results of deep deformation of the bridge foundation slope over the past three years, considering the integrity, systematicity, and indicative nature of the deformation observation data of the Hetaoshu Bridge foundation slope, it is the preferred warning indicator. Based on deep mining of monitoring data, a classification and early warning index for the stability of the Hetaoshu bridge foundation slope has been proposed. Engineering operation practice has shown that the proposed grading warning indicators are appropriate, which can provide an important reference for similar projects.