Submitted to: Transactions of the ASAE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 25, 1994
Publication Date: N/A
Interpretive Summary: Erosion in an earth emergency spillway can threaten the integrity of a dam during a flood flow. To determine the risk an individual dam poses to people and property downstream, a method of predicting spillway erosion is desired. A large-scale testing facility was constructed to study spillway erosion processes. This paper describes the test facility and presents initial test results. While designed for multiple uses, this test facility will allow the collection of a unique data base that will help describe how quickly and in what manner a spillway erodes. This information should be of value to the research community as well as engineers in the public and private sector.
Technical Abstract: The development and movement of gully headcuts can cause major damage in earth emergency spillways. A 1.8-m (6 -ft) wide and 29-m (96-ft) long flume with 2.4-m (8-ft) high sidewalls was constructed to perform research on headcut erosion and advance. Flume test flows of up to 3.4 cubic meters per second (120 cubic feet per second) can be examined. This paper describes the test flume, as well as, the supporting facilities such as a flow measurement flume, a drop structure, and an outlet control structure. Test results are presented for one cohesive soil placed and compacted at various combinations of soil moisture content and dry density. The headcut advance rate decreased as the average density and the average unconfined compressive strength increased. The influence of a sand layer on headcut advance was also examined.