Overturning stability of supported geomembrane tube for flood control

¹ State Key Laboratory of Hydraulic Engineering Simulation and Safety in Tianjin University, Tianjin 300072, China
² School of Civil Engineering, Tianjin University, Tianjin 300072, China

^* Corresponding author: guow@tju.edu.cn

Abstract

As a kind of rapid filling hydraulic structure, geomembrane tube can effectively act as flood barriers and cofferdams for flood risk management. L-shaped block is used to support geomembrane tube to prevent it from rolling. The contact force between the L-shaped block and the geomembrane tube is analyzed by using particle flow code (PFC^2D) software, and the overturning stability of the L-shaped block is calculated. The relationship between the key factors and the overturning stability was established. It is found that the central angle of the L-shaped block has little influence on the overturning stability. The overturning stability decreases with the increase of the initial pumping pressure. Keeping L_w/L_b unchanged, increasing Lb will improve the overturning stability where Lw and Lb are the width and the height of the Lshaped block. Under the ultimate water level, when 1.23 Lbcr < L_w≤1.55 L_bcr, the L-shaped block is in the state of overturning stability where L_bcr is the critical height of the L-shaped block. The initial pumping pressure is less than 0.152γL, the L-shaped block is in the state of overturning stability with L_w/L_bcr =1.0 where L is the cross-sectional perimeter of the geomembrane tube and γ is the unit weight of the filling liquid, on the contrary, L_w/L_bcr must be greater than 1 to ensure its overturning stability.