RIEDIGER

AUSTRIA (see also List of Individuals)

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8.8.1880 Wien/A - 20.10.1957 Wien/A

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Karl Riediger graduated as a civil engineer from Vienna Technical University in 1905 and moved than as a design engineer to Innsbruck in the County of Tyrol. He stayed in the early 1910s in South-Tyrol, today's Alto Adige Province of Italy, and was called from there in 1913 to Vienna at the Agricultural Ministry. Riediger was appointed in 1930 Honorary Lecturer of the Vienna Technical University and was retired at the end of World War II as a Ministerialrat.

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Riediger presented his main work toward hydraulics as PhD thesis in 1920. Scour was a concern for all working with flowing water, yet Riediger seems to have been the first who investigated the main characteristics of local erosion by a hydraulic approach. It should be noted that the sediment transport as a type of sediment surface erosion and deposition seems to be a simpler hydraulic problem, because it may be essentially described with a plane approach. Scour such as of bridge piers or other structures in a sediment bed involve always a spatial flow pattern with highly complex interactions between vortical water and sediment flows. Riediger subdivided his work into a theoretical approach which is applied to practical situations. He started from the Helmholtz vortex theorems as derived by Hermann von Helmholtz (1821-1894) to obtain velocity distributions downstream of flows with curved streamlines. He applied the results to various flow configurations investigated sometimes decades later. One case involves the end overfall problem corresponding to plane flow in an almost horizontal channel whose bottom abruptly ends and issues a jet onto a lower surface. This problem was considered by Rouse in the 1930s. Other problems investigated by Riediger were cascades as often used for the stabilization of Alpine Rivers, and bank erosion at river bends.

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_{Anonymous (1957). Karl Riediger. Zeitschrift des Österreichischen Ingenieurund Architekten-Vereins 102(23/24): 291.}

_{Österreichischer Ingenieurund Architekten-Verein (2003). Riediger. Personal communication. Riediger, K. (1919). Klarstellung der Projektsgrundlagen für das Donau-Kraftwerk bei Wien. Österreichische Wochenschrift für den Öffentlichen Baudienst 25: 374-375.}

_{Riediger, K. (1920). Die Theorie der Kolkbildung und deren Verwertung zur Berechnung der Fundierungstiefe von Wasserbauten an Gebirgsflüssen und Wildbächen. Gerold: Wien.}

_{Riediger, K. (1936). Die staatlichen Massnahmen auf dem Gebiete der Gewässerregulierungen, den gegenwärtigen Stand dieser Massnahmen und die Rentabilität der Wasserbauten. Wasserwirtschaft und Technik 3(33/34): 373-381.}