Concept for an integral approach to explore the behavior of rock salt caverns under thermo-mechanical cyclic loading in energy storage systems     

Elham Mahmoudi  Kavan Khaledi  Achim von Blumenthal  Diethard König  Tom Schanz 《Environmental Earth Sciences》2016,75(14):1069

  相似文献   

Seismic wave propagation in laterally inhomogeneous poroelastic media via BIEM     

Petia Dineva  Maria Datcheva  George Manolis  Tom Schanz 《国际地质力学数值与分析法杂志》2012,36(2):111-127

This work addresses in‐plane pressure P and vertically polarized shear SV seismic wave propagation in a finite, laterally inhomogeneous, multilayered poroelastic geological region resting on the homogeneous elastic half‐space. The particular approach followed here is based on a combination of the (i) viscoelastic approximation (isomorphism) to Biot's equations of dynamic poroelasticity and on the (ii) boundary integral equation method (BIEM) using frequency‐dependent fundamental solutions of the governing wave equations. The problem is formulated under plane strain conditions and time‐harmonic motions are assumed. Validation of the viscoelastic isomorphism and verification of the BIEM is done by solution of benchmark examples. These simulation studies reveal that the proposed methodology is able to depict a sensitivity of the seismic signals recovered to the following parameters: (i) poroelastic properties of fluid saturated layers; (ii) lateral geological inhomogeneity; (iii) surface topography and (iv) frequency content and direction of the incident wave. It is concluded that the combination of viscoelastic isomorphism with BIEM software provides an effective numerical tool for evaluating site‐effect phenomena in multilayered, fluid saturated geological regions with complex geometry. The numerical results obtained demonstrate that dynamic poroelasticity interacting with other physical peculiarities of the Earth's surface layers, such as lateral heterogeneity, material properties along the wave path, local geological profile and type of elastic wave, gives rise to complex seismic signals on the free surface at the site of interest. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Asymptotic expansions in the perturbed two-body problem with application to systems with variable mass     

Ferdinand Verhulst 《Celestial Mechanics and Dynamical Astronomy》1975,11(1):95-129

The main theorems of the theory of averaging are formulated for slowly varying standard systems and we show that it is possible to extend the class of perturbation problems where averaging might be used. The application of the averaging method to the perturbed two-body problem is possible but involves many technical difficulties which in the case of the two-body problem with variable mass are avoided by deriving new and more suitable equations for these perturbation problems. Application of the averaging method to these perturbation problems yields asymptotic approximations which are valid on a long time-scale. It is shown by comparison with results obtained earlier that in the case of the two-body problem with slow decrease of mass the averaging method cannot be applied if the initial conditions are nearly parabolic. In studying the two-body problem with quick decrease of mass it is shown that the new formulation of the perturbation problem can be used to obtain matched asymptotic approximations.  相似文献   

Workshop on Volumetric Estimation     

G. A. Kingston  M. David  R. F. Meyer  A. T. Oeenshine  S. Slamet  J. J. Schanz 《Mathematical Geology》1978,10(5):495-499

  相似文献   

Light climate as the key factor controlling the spring dynamics of phytoplankton in Lake Zürich     

Willi Bleiker  Ferdinand Schanz 《Aquatic Sciences - Research Across Boundaries》1997,59(2):135-157

During the spring seasons of 1983, 1986 and 1987 the development of phytoplankton in Lake Zürich was investigated (from February to May) using samples taken at short term intervals. The aim was to describe the effects of the short term dynamics of environmental factors on the algal growth. The results could then be used to discuss the existing theories to assess the start of phytoplankton growth pulses in spring. Only 7 to 10 days without wind driven vertical mixing were required in spring to start the first growth pulse, despite of a still very unstable water column (sometimes inverse thermal stratification). Mainly flagellates andStephanodiscus hantzschii increased their biomass and achieved net growth rates of 0.1 and up to 0.65 d⁻¹ respectively. During such a phase the mixing depth was always smaller than the euphotic depth. Later on, at the start of the spring bloom (=last growth pulse in spring before the clear water stage), the intensity of vertical mixing as well as the mixing depth were markedly reduced due to an increase in heat input and low wind. Then flagellates dominated (contribution up to 75.5% of the areal biomass reaching 60 g fresh weight m⁻²) and the growth rate rose to a maximum of 0.65 d⁻¹. Standard models of critical depth considers that there is only a biomass increase if the mixing depth is smaller than the depth of a water layer positive balanced between production and respiration. This model for determining the beginning of a phytoplankton growth pulse in spring takes no account of the favorable light conditions for phytoplankton cells at calm and sunny days in February and March. The newly developed threshold value model takes these situations into account: It assumes that the phytoplankton biomass increases when the calculated effective light climate is equal or greater than a previously fixed threshold. The calculations are based on the mean light intensity within the mixed layer at windy days or within the euphotic depth (z _eu) at calm days. In Lake Zürich a minimum of 0.2 10⁶ J m⁻²d⁻¹ (=0.9 mol quanta m⁻²d⁻¹) has to be reached or surpassed in at least 3 days before an exponential increase of algal biomass can occur. The value does not depend on short term fluctuations in neither radiation nor mixing depth. It seems that this value is rather low comparing with those of investigations in other water bodies (up to 0.8 10⁶ J m⁻² d⁻¹) but high related to values from algal cultures (0.02 10⁶ J m⁻²d⁻¹). As the weather can only be forecasted a few days ahead with any certainty the period for a more or less accurate prediction of an algal bloom is restricted to about 1 to 5 days.  相似文献   

Thermodynamics of the xanthoconite-proustite and pyrostilpnite-pyrargyrite phase transition as determined by abrasive stripping voltammetry     

Birgit Lange  Fritz Scholz  Hans-Joachim Bautsch  Ferdinand Damaschun  Gert Wappler 《Physics and Chemistry of Minerals》1993,19(7):486-491

The electrochemical reduction of xanthoconite, proustite, pyrostilpnite, and pyrargyrite was studied by abrasive stripping voltammetry, a technique which is based upon a preliminary mechanical transfer of trace amounts of the mineral onto the surface of a paraffin impregnated graphite electrode. Because the electrochemical reduction proceeds near to reversibility and is very similar for each pair of minerals, the peak potentials in differential pulse voltammetry can be used to calculate the standard enthalpy of phase transformation of xanthoconite to proustite and of pyrostilpnite to pyrargyrite: _T H _{(xanth proust)} ^O = 35.46 ± 14.15 kJ/mol and _T H _{(pyrostilp pyrarg)} ^O = 38.85 ± 6.60 kJ/mol. These values are not accessible otherwise until now.  相似文献   

Die Verteilung des SO2-Gehaltes der Luft im Stadtgebiet von Wien     

Anna Bangerl  Ferdinand Steinhauser 《Theoretical and Applied Climatology》1959,10(1):132-153

Zusammenfassung An zahlreichen über das ganze Stadtgebiet von Wien verteilten Beobachtungsstellen wurden vom September 1956 bis September 1957 an je vier Wochen lang ausgesetzten, mit einem Absorptionsmittel getränkten Baumwollappen SO₂-Ablagerungen gesammelt. Die gefundenen SO₂-Mengen zeigen eine stark unterschiedliche Verteilung im Stadtbereich und einen deutlichen Jahresgang mit einem Maximum im Winter und einem Minimum im Juli. Der Einfluß meteorologischer Faktoren auf den SO₂-Gehalt der Luft und seine Änderungen wird unter besonderer Berücksichtigung der orographischen Verhältnisse und örtlicher SO₂-Quellen eingehend diskutiert. Abschließend wird auch über eine Analyse von Schneeproben auf berichtet.

---

Summary During the period September 1956 to September 1957 the amount of SO₂ deposited from the atmosphere was observed at numerous locations in the town of Vienna. The observations were made by means of cotton rags, soaked with an absorbing chemical, and each rag was exposed for four weeks. The amounts of SO₂ show great differences within the area, and a pronounced annual variation, with a maximum in winter and a minimum in July. The influence on the SO₂ content of the air of meteorological factors is discussed in detail, with special regard to variations by orographic conditions and local SO₂ sources. Additional determinations on snow samples are reported.

---

Résumé Des prélèvements de SO₂ par absorption sur des bandes de coton imprégné, laissées sur place pendant quatre semaines, ont été faits en de nombreux endroits de l'agglomération viennoise de septembre 1956 à septembre 1957. Les quantités de SO₂ varient beaucoup selon les endroits et la saison; elles sont maximum en hiver et minimum en juillet. Etude des facteurs météorologiques agissant sur la répartition du gaz en tenant compte en particulier du relief et des sources locales d'anhydride sulfureux. On a également déterminé la teneur de d'échantillons de neige.

---

---

Mit 4 Textabbildungen  相似文献   

Statistische Untersuchung der Inversionen im Luftraum über Wien     

Ferdinand Steinhauser 《Meteorology and Atmospheric Physics》1960,11(4):427-457

Zusammenfassung Der Untersuchung liegen die Ergebnisse täglicher bis in die Stratosphäre reichender Radiosondenaufstiege von 3 Uhr und 15 Uhr MGT aus den Jahren 1952 bis 1956 zugrunde. Für jeden Termin und für jeden Monat werden die Häufigkeiten der Inversionen in der Troposphäre in Abhängigkeit von der Höhenlage der Untergrenzen für alle Inversionen und gesondert für die untersten Inversionen angegeben und die Besonderheiten der Jahresgänge der Inversionshäufigkeiten und ihrer Änderung mit der Höhe eingehend diskutiert. Es wird auch angeführt, wie oft in jedem Monat gleichzeitig mehrere Inversionen übereinander vorkommen. Eine Abbildung zeigt, daß der übergang von großen Inversionshäufigkeiten in den untersten 3000 m im Winterhalbjahr zu kleinen Inversionshäufigkeiten im Sommerhalbjahr fast sprunghaft vom März zum April erfolgt, während der Wiederanstieg der Inversionshäufigkeit im Herbst etwas langsamer vor sich geht und sich auf die Zeit vom September bis zum November erstreckt. Zur Charakterisierung der Mächtigkeit der Inversionen werden für jeden Monat und für beide Termine für alle Inversionen und gesondert für die untersten Inversionen auch die Häufigkeiten der verschiedenen Schichtdicken der Inversionen mitgeteilt und ihre Änderungen im Laufe des Jahres wie auch die Häufigkeiten der verschiedenen Schichtdicken in Abhängigkeit von der Höhenlage der Untergrenze der Inversionen besprochen. Die Häufigkeit der Inversionen mit Schichtdicken kleiner als 400 m zeigt keinen ausgesprochenen Jahresgang, während die Inversionen mit Schichtdicken über 400 m im Winterhalbjahr viel häufiger vorkommen als im Sommerhalbjahr, wobei die Abnahme der Häufigkeit wieder vom März zum April fast sprunghaft erfolgt, die Zunahme der Häufigkeit dieser Inversionen im Herbst sich aber in einem langsameren Anstieg vom August bis Oktober erstreckt. Zur weiteren Charakterisierung der Struktur und der Mächtigkeit der Inversionen werden Häufigkeitsverteilungen der Temperaturdifferenzen zwischen Ober- und Untergrenze der Inversionen und die Abhängigkeit dieser Häufigkeitsverteilung sowie der Häufigkeitsverteilungen der Temperaturgradienten in den Inversionsschichten von der Höhenlage der Inversionen wiedergegeben und die Temperaturdifferenzen zwischen Ober-und Untergrenze der Inversion zur Dicke der Inversionsschichten in Beziehung gesetzt.

---

Summary The present investigation is based upon daily radio soundings, reaching the stratosphere, at 0300 and 1500 GMT in the years 1952 through 1956. The frequency of inversions in the troposphere and its dependence on the height of their lower boundary is given for all inversions at each observation time and month. The same is given for the lowest inversions only. The pecularities of the annual variations of the inversion frequencies and their variations with height are discussed in detail. Further, the frequency of multiple inversions is stated for each month. The transition of inversion frequencies in the first 3000 metres from high values in the winter semester to low values in the summer semester occurs almost discontinuously between March and April, and is shown in a graph. The increase of the inversion frequency between September and November is somewhat slower. The vertical extent of inversion layers for each month and observation time is given for all inversions and, separately, for the lowest inversions only. The frequencies of the vertical extent of inversion layers and their variations during the year as well as their dependence on the height of the lower boundary of the inversions are discussed. The frequency of inversions with a thickness less than 400 metres shows no pronounced annual variation, and the inversions with a thickness greater than 400 metres are much more frequent in the winter than in the summer. There is a sudden drop of frequencies between March and April and a more gradual increase between August and October. A further characterization of the structure and vertical extent of inversions is given by the frequency distributions of temperature differences between upper and lower boundary of the inversions. These frequency distributions as well as the frequency distributions of temperature gradients within the inversion layer and their dependence upon the height of the inversion are presented. Finally the relations between temperature difference from upper to lower boundary and thickness of the inversion are discussed.

---

Résumé Les résultats des radio-sondages quotidiens de 3 h. et de 15 h. (1952–1956) ayant atteint la stratosphère forment la base de cette étude qui examine la fréquence des inversions troposphèriques en fonction de leur altitude et de leur réparition au cours de l'année et qui recherche avec quelle fréquence ces inversions sont multiples. Les nombreuses inversions hivernales au-dessous de 3000 m. se raréfient brusquement de mars à avril, tandis qu'elles augmentent de nouveau, mais propgressivement, de septembre à novembre. L'importance des inversions est mise en évidence par leur épaisseur dont l'auteur étudie la répartition de fréquence en fonction de l'époque de l'année et de l'altitude. Les inversions d'épaisseur inférieure à 400 m. présentent une fréquence à peu près constante au cours de l'anné, tandis que celles qui ont plus de 400 m. sont nettement plus fréquentes en hiver; là aussi le passage du régime hivernal à celui d'été se fait brusquement de mars à avril, et le passage inverse d'août à octobre, progressivement. Enfin les différences de température entre la base et le sommet de l'inversion ainsi que le gradient vertical de température dans l'inversion sont considérés en fonction de leur altitude; l'écart de température base-sommet est également examiné par rapport à l'épaisseur de l'inversion.

---

---

Mit 2 Textabbildungen  相似文献   

Osmotic suction of highly plastic clays     

Yulian Firmana Arifin  Tom Schanz 《Acta Geotechnica》2009,4(3):177-191

This paper presents a study on osmotic suction of compacted highly plastic clays. Two different types of bentonite (i.e. Calcigel and a bentonite from India called herein as Indian bentonite) were used. Squeezing technique was utilized to obtain soil pore-water of the specimen. Using relationship between electric conductivity and osmotic pressure of salt solution, osmotic suction of soil pore-water was obtained. Additional tests (i.e. total and matric suction using filter paper method and swelling pressure using constant volume swelling pressure test) were performed. The results show that osmotic pressure of soil pore-water obtained decreases by increasing squeezing pressure. Based on experimental result, osmotic suction of the specimen is osmotic pressure of the first drop of extracted soil pore-water. An empirical method was suggested to determine the squeezing pressure in squeezing technique. In addition, roles of osmotic suction in thermo-hydro-mechanical behavior of highly plastic clays were presented and discussed in the paper.  相似文献   

Geology of the southern Zambales Ophiolite Complex, Luzon, Philippines     

Graciano P. Yumul JR    Carla B. Dimalanta and  Ferdinand T. Jumawan 《Island Arc》2000,9(4):542-555

Abstract Field, geochemical and geophysical evidence show that the southern Zambales Ophiolite Complex attained its present-day configuration through the juxtapositioning of an arc terrane (San Antonio massif) to a back-arc crust (Cabangan massif). The San Antonio massif manifests island arc-related characteristics (i.e. spinel XCr [Cr/(Cr + Al)] >0.60; mostly plagioclase An92–95; pyroxene crystallizing ahead of plagioclase; orthopyroxene as an early, major crystallizing phase) which cannot be directly parental to the Cabangan massif transitional mid-ocean ridge basalt to island arc tholeiitic volcanic carapace. The two massifs are believed to be separated by a left-lateral strike–slip fault, the Subic Bay Fault Zone. Apart from the presence of highly sheared, allochthonous outcrops, the Subic Bay Fault Zone is generally defined by northwest–southeast trending magnetic and bouguer anomalies. The San Antonio massif was translated southward from the northern part of the Zambales Ophiolite Complex through the Subic Bay Fault Zone. This resulted into its suturing with the Cabangan massif and could have led to the formation of the present-day Subic Bay.  相似文献