Full-Scale Testing of Concrete-Enhanced Synthetic Turf Revetment Systems for Dam Spillway and Levee Overtopping Protection

Concrete-Enhanced Synthetic Turf (CEST) Revetment System is an innovative technology developed for dam spillway and levee overtopping protection. CEST is a unique, fiber reinforced concrete revetment consisting of a high-friction, structured geomembrane overlain by an engineered synthetic turf which is infilled with a high-strength, 5000 psi (34 MPa) cementitious material.
An extensive full-scale testing program was conducted on CEST at Colorado State University - Engineering Research Center (CSU). The steady state testing consisted of 1.5, 3.0 and 5-ft (0.46, 0.91 and 1.52-m) overtopping depths in the 2H:1V sloped flume. 20 hours of testing was performed up to a maximum velocity of 29.2 fps (8.9 m/sec). Evaluations included the performance of the intact system; the resilience to impact and abrasion under heavy debris loads (concrete rubble); and, the function in an intentionally damaged state. Also, a sluice gate was placed in the flume to create hydraulic jumps. The CEST dissipated hydraulic jump loadings of as much as 30 horsepower per foot of width (22.4 kW). The CEST experienced no uplift, damage, instability, or subgrade erosion. The CEST performed exceptionally well in maintaining the underlying, erodible subgrade soils during these severe and varied tests.
This paper defines the components of the CEST; describes the testing facility and procedures; provides an explanation of the preparation of the test trays; and reports the results.