https://eprints.nwisrl.ars.usda.gov/id/eprint/457 2017-01-13T20:24:31Z info:eu-repo/semantics/descriptiveMetadata https://eprints.nwisrl.ars.usda.gov/id/eprint/457/ Evaluation of Drop-Check Structures for Farm Irrigation Systems Humpherys, A.S. Mass Import - unclassified SMALL drop/check structures of various designs in the 28 to 115 L/s (1 to 4 cfs) flow range were installed in 1966 with their field performance evaluated in 1969. They were again evaluated in 1984 after 19 years of service. The parameters used to evaluate the structures included cost, structural integrity, stability, hydraulic performance and ditch erosion control capability. A numerical rating was given in each category. A precast concrete headwall with a rock-lined basin or plunge pool was the most economical and one of the most effective structures; however, special consideration must be given to provide sufficient headwall length and cutoff wail depth. Cast-in-place concrete structures were the most stable and generally the most costly with variable performances. Based on the study results and observations, conclusions and recommendations were made to improve the design of small drop structures. 1986 Article NonPeerReviewed application/pdf en https://eprints.nwisrl.ars.usda.gov/id/eprint/457/1/575.pdf Humpherys, A.S. (1986) Evaluation of Drop-Check Structures for Farm Irrigation Systems. Transaction of the ASAE. 29(2):505-511,516. 0575 0575 info:eu-repo/semantics/objectFile info:eu-repo/semantics/humanStartPage