In this study, we conducted hydraulic tests to evaluate the energy dissipation capabilities of different types of protective structures in areas downstream of open check dams. Our findings were used as the basis to formulate
modified guidelines for such structures, which are as follows: To prevent scour at the foundations of protective structures,a coefficient of 2.5 can be applied for the length of rigid protective structures and a coefficient of 3 can be applied for the distance between primary and secondary dams and for the length of soft protective structures. The results of the hydraulic tests revealed that stone aprons provided the greatest energy dissipation effect, followed by hexa-hollow trileg structures, secondary dams, stilling basins, and concrete aprons, with scour depth reduction rates of 90%, 82%,70%, 64%, and 62%, respectively. Moreover, these protective structures could all be used to reduce the kinetic energy of water flow.
Key Words: Local scour, open check dam, protection strategy, protective structure