Steady State Overtop Testing

The Hydraulics Laboratory at Colorado State University – Engineering Research Center (CSU) performed testing of the HydroTurf® Revetment System in accordance with ASTM D 7277 – Standard Test Method for Performance Testing of Articulated Concrete Block (ACB) Revetment Systems for Hydraulic Stability in Open Channel Flow. The results of the testing were analyzed in accordance with ASTM D 7276 – Standard Guide for Analysis and Interpretation of Test Data for Articulating Concrete Block (ACB) Revetment Systems in Open Channel Flow.

HydroTurf was installed in the flume (2H:1V slope) on a sandy-loam subgrade. A horizontal seam was intentionally placed in the system near the bottom of the flume in order to evaluate its strength under extreme hydraulic forces.

The HydroTurf was tested at 1.5, 3, and 5-ft steady-state, overtop depths for a total of 12 hours. CSU reported stable performance values with no erosion at 29.2 fps for velocity. Since no instability, deformation, loss of intimate contact or damage of the system, and no erosion of the underlying subgrade occurred; this value of velocity is not a maximum performance threshold.

Section of the Installed HydroTurf 
System in the Overtopping Flume

Illustration of Section of the Installed HydroTurfTM System in the Overtopping Flume

Section of the Installed HydroTurf System in the Overtopping Flume

Steady State Hydraulic Testing of HydroTurf at CSU

Photo of Steady State Hydraulic Testing of HydroTurf at CSU

Steady State Hydraulic Testing of HydroTurf at CSU

The published maximum performance thresholds / permissible design values for various erosion and revetment technologies are shown in the following graph. HydroTurf clearly outperforms these other systems.

Permissible Design values of Velocity for Steady State High Flow Application*

Chart Illustration of Permissible Design Values Velocity for Steady State High Flow Applications

Permissible Design Values Velocity for Steady State High Flow Applications