{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:39:42Z","timestamp":1760236782737,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,24]],"date-time":"2021-12-24T00:00:00Z","timestamp":1640304000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/51527\/2011"],"award-info":[{"award-number":["SFRH\/BD\/51527\/2011"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Laboratory of Hydraulic Constructions (LCH), Ecole Polytechnique F\u00e9d\u00e9rale de Lausanne (EPFL)","award":["000400032502"],"award-info":[{"award-number":["000400032502"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Water"],"abstract":"<jats:p>Fluctuating bottom-pressures on stepped chutes are relevant for the spillway design. An abrupt slope reduction causes a local alteration of the bottom-pressure development. Little information is available regarding the air\u2013water flow properties near an abrupt slope reduction on stepped chutes, particularly on the local pressure evolution. Nevertheless, the option of providing a chute slope reduction may be of interest in spillway layout. The experiments presented herein include pressure distributions on both vertical and horizontal step faces, subsequent to an abrupt slope reduction on stepped chutes. A relatively large-scale physical model including abrupt slope reductions from 50\u00b0 to 18.6\u00b0 and from 50\u00b0 to 30\u00b0 was used, operated with skimming flow. The data indicate a substantial influence of the tested slope reductions on the bottom-pressure development. In the vicinity of the slope reduction, the mean pressure head near the edge of the horizontal step face reached 0.4 to 0.6 times the velocity head upstream of the slope reduction, for critical flow depths normalized by the step height ranging between 2.6 and 4.6.<\/jats:p>","DOI":"10.3390\/w14010041","type":"journal-article","created":{"date-parts":[[2021,12,27]],"date-time":"2021-12-27T01:03:37Z","timestamp":1640567017000},"page":"41","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5162-6332","authenticated-orcid":false,"given":"Mohammad J.","family":"Ostad Mirza Tehrani","sequence":"first","affiliation":[{"name":"Laboratory of Hydraulic Constructions (LCH), Ecole Polytechnique F\u00e9d\u00e9rale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland"},{"name":"Faculty of Civil Engineering, K.N. Toosi University of Technology, Tehran 1996715433, Iran"}]},{"given":"Jorge","family":"Matos","sequence":"additional","affiliation":[{"name":"CERIS, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal"}]},{"given":"Michael","family":"Pfister","sequence":"additional","affiliation":[{"name":"Civil Engineering Department, Haute Ecole d\u2019Ing\u00e9nierie et d\u2019Architecture de Fribourg (HEIA-FR, HES-SO), CH-1705 Fribourg, Switzerland"}]},{"given":"Anton J.","family":"Schleiss","sequence":"additional","affiliation":[{"name":"Laboratory of Hydraulic Constructions (LCH), Ecole Polytechnique F\u00e9d\u00e9rale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,24]]},"reference":[{"key":"ref_1","unstructured":"Minor, H.-E., and Hager, W.H. (2000, January 22\u221224). Air Entrainment and Safety Against Cavitation Damage in Stepped Spillways over RCC Dams. 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