Resistance of Laminar Drain Reinforcement Levee against Overflow Erosion

Abstract

As a method for reinforcing against overflow erosion and infiltration, this study investigated a laminar drain reinforcement (LDR) levee, in which the drain layers are set on the back slope and connected to concrete panels using geogrid layers. We examined the resistance against overflow erosion of the LDR levee by large-scale model tests with a 1 m high model levee. We also compared the resistance of an armored levee, which is covered with concrete panels, and a GRS (geosynthetic-reinforced soil) levee, in which the geogrid layers are laid in the levee body with connecting concrete panels. The results of the model tests reveal that: (1) the LDR levee can maintain the initial height and shape for more than 150 min; by comparison, the times to levee failure were 87 and 102 min for the armored and GRS levees, respectively; (2) the LDR levee was shown to have a highly tenacious structure offering resistance to overflow erosion. In particular, panels easily flowed out with a slight gap (less than 1 cm) for the armored levee, while the LDR levee was able to prevent flowing out of panels and the erosion of the levee body, thanks to the laminar drain at the back slope, even when the gaps between the surface panels exceeded 5 cm.

Experimental Investigations on Pullout Behavior of HDPE Geogrid under Static and Dynamic Loading

“…In recent decades, geosynthetic-reinforced soil (GRS) structures have been constructed more frequently, such as subgrade [1,2], embankment [3,4], retaining walls [5][6][7], slopes [8,9], and landfills [10,11], because they have the advantages of low cost [12], simple construction, and environmental protection [8,13] and can deform without damage. High-density polyethylene (HDPE) geogrids, as an example of the important geosynthetics reinforcement materials, are commonly adopted in many GRS structures, such as reinforced soil retaining wall and reinforced slopes, especially for steep slopes [14][15][16], because of their excellent mechanical characteristics such as high strength, high elongation, and durability.…”

Sustainable Use of Geosynthetics in Dykes

“…The improvement of dykes cross-sections by using different geosynthetics has developed to be state-of-the-art as geosynthetic solutions, used with natural materials, have proven to provide strength and flexibility, imperviousness and drainage, durability and robustness or to control degradation [1,3,8,[10][11][12]. These technologies bring not just structural defense but more time for evaluating risk and providing emergency response to populated areas that are threatened by rising water levels [8,11]. They can be designed to control the interaction of water and soil according to the individual and local requirements to allow for an excellent execution of waterways and flood protection structures [1].…”