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Geschichte der Bautechnik. Die Entwicklung des schweizerischen Flussbaus
(1986)Schweizer BaublattJournal Article -
Combined measurements of subglacial water pressure and surface velocity of Findelengletscher, Switzerland: conclusions about drainage system and sliding mechanism
(1986)Journal of GlaciologyDuring the snow-melt season of 1982, basal water pressure was recorded in 11 bore holes communicating with the subglacial drainage system. In most of these holes the water levels were at approximately the same depth (around 70 m below surface). The large variations of water pressure, such as diurnal variations, were usually similar at different locations and in phase. In two instances of exceptionally high water pressure, however, systematic ...Journal Article -
Ice avalanches: Some empirical information about their formation and reach
(1985)Journal of GlaciologyA study intended to be mainly of practical use in the prediction of ice-avalanche hazards was carried out. About 100 ice avalanches, mostly from the Alps, were documented. Starting zones of these ice avalanches could be classified by using simple terrain characteristics. Ice avalanches from some starting zones at relatively low altitudes and with large, homogeneously inclined bedrock planes occur predominantly in summer and autumn. No ...Journal Article -
Electrical resistivity soundings of glacier beds: A test study on Grubengletscher, Wallis, Swiss Alps
(1984)Journal of GlaciologyElectrical resistivity sounding, using electrodes which are lowered directly to the ice–rock interface in bore holes, is proposed as a technique for studying the exact position of glacier beds, as well as their lithological characteristics. A test study is described on Grubengletscher, a partially cold Alpine glacier in Switzerland. Results of soundings along a 400m long profile indicate that previous depth determinations, based on radio ...Journal Article -
On pseudo-uniform flow in open channel hydraulics
(1984)Acta MechanicaThe differential equation that governs the longitudinal variation of the surface profileh(x) in steady plane channel flow is qualitatively discussed for the case of pseudo-uniform flow states. The solutions are either of the cnoidal or solitary wave type. It is shown that, among all cnoidal waves, solitary waves have minimum energy head. Further, surface profiles mustbreak whenever the Froude-number exceeds the value2–√ (which is close ...Journal Article -
Approximate treatment of the plane hydraulic jump with separation zone above the flow zone
(1983)Journal of Hydraulic ResearchThe usual hydraulic jump with separation zone above the flow zone can be approximately treated by balancing momentum in the flow direction and perpendicular to it. These relations yield the simplified characteristics of the jump; they are discussed and compared with the results of a typical experiment.Journal Article -
Formation and effects of alternate bars
(1984)Journal of Hydraulic EngineeringMajor river regulation works have often resulted in alternate bar formation. Experimental work is described which provides more information on this phenomenon. Alternate bar formation is closely associated with meandering, inferring that alternate bar formation is caused by flow induced periodic disturbances of the horizontal velocity profile. Based on these considerations a criterion has been developed which defines the upper limit of ...Journal Article -
Frequency and characteristics of glacier floods in the Swiss Alps
(1983)Annals of GlaciologyDamage due to glacier floods in the Swiss Alps occurs about once every two years at present, despite the pronounced retreat of glaciers during the twentieth century and the installation of many water reservoirs, which act as flood retention basins. Over half (60 to 70%) of the observed floods are caused by outbursts of marginal glacier lakes or sudden breaks of ice dams, and 30 to 40% by ruptures of water pockets. In a glacierized mountain ...Journal Article -
The uplift of Unteraargletscher at the beginning of the melt season: a consequence of water storage at the bed?
(1983)Journal of GlaciologyResults of systematic movement studies carried out by means of an automatic camera on Unteraargletscher since 1969 are discussed together with supplementary theodolite measurements made at shorter intervals and over a longer section of the glacier. In addition to the typical spring/early summer maximum of velocity known from other glaciers, an upward movement of up to 0.6 m has been recorded at the beginning of the melt season. It was ...Journal Article