Gestion des risques et des crises liés à l'instabilité des carrières souterraines abandonnées

Instability of underground excavations and karsts generally leads to violent events that affect zones which are difficult to locate precisely. For this reason, monitoring and alarm systems are not very efficient and risk management must therefore be essentially focused on prevention. In France, the aim of such prevention is to find a balance. Although the French legal and regulatory framework is rational, it is deficient in certain respects, and particularly faces difficulties concerning implementation as revealed by the development of the Plans of Exposure to Risks (PER) having taken too long. The comments made during the symposium held at Nainville-les-Roches have lead to the proposal of a number of improvements for the present system:

-promote a global approach which integrates risk management into land-use planning, ensuring coherence between national, regional, departmental and local plans,

-develop an operational approach for each “basin” at risk,

-speed up hazard mapping by its separation from regulatory procedures,

-develop plans for crisis management at a municipal level; bring experts, technical services and emergency services closer together and involve populations at risk in the preparation process,

-launch an operational information policy on the risks and develop a true culture of risk prevention,

-set up a local public service responsible for risk management of underground excavations within areas of greatest risk.

     

Évaluation et cartographie des risques géotechniques de dégradation des ouvrages d'assainissement une aide à la gestion des eéseaux

A sewage collector can be considered as a composite structure, comprising the collector itself and its geological envelope both sticking together. Its durability is directly linked with the geotechnical behaviour of the soil, as testified by the analysis of numerous pathological cases observed in structures which it is possible to inspect in the Paris urban area. The author proposes a methodology enabling these parameters of influence to be taken into account without recourses to costly procedures of investigation. Based on the principles of mapping risks of soil movements, the method involves two stages:

-The geotechnical classification of soils in terms of their vulnerability to stresses to which they may be subjected.

-The establishments of maps or profiles predictive of risks. in accordance with qualitative criteria derived from the interpretation of existing geological information.

Tested and applied to the inspectable sewage system of the Val-de-Marne and Seine-Saint-Denis Departments, this procedure can be extended to urban systems where sufficient geotechnical documentation is available to obviate the need for any in situ investigation.     

“Cité des Affaires”办公楼

正这个地块是圣埃蒂安市中心与新的Chateaucreux街区之间的重要联络点,形成了一个主要的入口。它也构成了将多个政府部门聚集到一起的极点。生活服务设施和休闲设施也是共用企业餐厅、咖啡厅、市区旅游局组合的一部分。这个理念是在地块上修建一个与相邻街道相呼应的‘连续体’。直线式建筑自下向上建造,在展现地平线的同时也与其相呼应,形成一栋低矮的无障碍建筑——一栋开设有宽敞的庭院并将粗犷的悬壁结构吊起的建筑。     

Etude des caractéristiques hydrodynamiques des sols par la méthode TDR (time domain reflectometry)

The object of this laboratory study was to determine any relationship between the soil volumetric water content θ, the dielectric constant (permissivity –ε), and the impedance of the same soil (R₁). Time domain reflectometry (TDR) allows the measurement of material dielectric constant and impedance by determining electromagnetic pulse transit time and pulse attenuation. Using the established relations of the TDR method, it is possible to trace the volumetric water content and electric conductivity (or the impedance) of the soil simultaneously in a continuous manner. It was hoped that, thereafter, it may be possible to calculate the soil suction using soil permissivity and impedance. TDR measurements were carried out for different leachates and soils. Relationships found in previous work by the authors were used to compare water contents given by the TDR method with water contents obtained by drying the soil samples. The test results showed a relationship between water content and soil type and the electrical conductivity of the liquid when the TDR parameter was soil impedance. It was concluded that permissivity could be used to characterise the soil's water content. This relationship is used to study the changes in bentonite water content during air drying. Volumetric water content and impedance vs time curves allows the determination of shrinkage limit.     

Kfz-Pflichtstellplätze außerhalb des Bauplatzes

Kfz-Stellpl?tze in einer Entfernung von 940 m liegen nicht mehr im "Umkreis von zirka 500 m". Auf Besonderheiten eines Bezirkes oder Bezirksteiles (hier: der Wiener Innenstadt) kann in diesem Zusammenhang nicht Bedacht genommen werden.     

Einflüsse des geochemischen Milieus und der Eintragsform auf die Verteilung der anorganischen Redoxspezies des Arsens im Grundwasser

This study was initiated in order to investigate relationships between the arsenic species distribution, the geochemical conditions and the input source of As in groundwater. Water samples characterized in the study originated from four locations representing five different input sources. The redox conditions varied vrom oxid to sulfidic. Measurements indicate – as expected – that the As(III)/As(V)-species distribution is closely related to the redox environment. Nevertheless it cannot be predicted using the redox potenzial and the Nernst equation. Results clearly reveal a dependence of the species distribution on the As input species. Related to the redox conditions, an oxidation path of As(III) can be distinguished from a reductuion path of As(V). The kinetics of the redox reactions depend on the availability of reaction partners.     

Multitracer-Versuch im kontaminierten Grundwasser des Testfeldes Süd

A natural gradient multitracer-experiment (fluorescein, eosin, naphthionate, bromide) was performed at an experimental site with contaminated groundwater. The break-through curves were evaluated by fitting an analytical solution of the transport equation to the breakthrough curves, different calculation methods based on the tracer arrival times, and with numerical transport simulations. The observed transport direction differed markedly from the expected direction based on equipotential lines. The method of temporal moments proved to be best suited to describe the transport velocity. Transverse dispersivites could not be evaluated satisfactorily, even though numerous observation wells existed. The interactions of the tracers and nonaqueous phase liquids (octanol, tar oil, lubrication oil) were investigated with laboratory experiments. None of the tracers was affected. Fluorescein and eosin could be applied successfully even when nonaqueous phase liquids were present, but the application of naphthionate suffered from high background fluorescence.     

Methoden zur Abschätzung der Verschmutzungsempfindlichkeit des Grundwassers

The increasing threat of groundwater contamination by pollutants has led to the development of methods to assess groundwater vulnerability on a regional scale. An assessment of groundwater vulnerability will also be required by the coming EU framework directive on water. The concept of groundwater vulnerability is discussed and available methods are presented. These include hydrogeological complex and setting methods, analogue relations and index methods, point rating and matrix systems, mathematical models and statistical approaches. The methods and their principal characteristics are explained and summarised with emphasis on their regional usability.     

Heranrückende Wohnbebauung; Einwendungen des gewerblichen Betriebsanlageninhabers

Die Einwendung des anrainenden Betriebsinhabers, dass er "ein rechtliches Interesse daran (hat), dass durch faktisches Heranrücken von als Wohnungen genützten Objekten an seine Betriebsanlage seine gewerberechtlichen Befugnisse nicht (zus?tzlich) beeintr?chtigt werden", stellt keine Einwendung im Rechtssinne dar, weil daraus nicht zu erkennen ist, in welchem geschützten subjektiv-?ffentlichen Recht sich der Nachbar durch die beabsichtigte Bauführung für verletzt erachtet.     

Comportement à l’eau des roches argilo-marneuses, suivi du gonflement, importance de la minéralogie et des textures

In the presence of water, clayey-calcareous rocks display behaviours which are often significantly different. Through the study of four materials which are representative of the marly formations commonly met on the occasion of road construction, the authors show how this behaviour depend on the mineralogical and textural characteristics of rocks. After reminding the main mechanisms of swelling phenomena the authors characterize the selected materials on the one hand through the measured physical and physico-chemical parameters and on the second hand through the mineralogical and textural characteristics obtained from X-ray diffractometry and scanning electron microscopy. The materials are then studied firstly in “free swelling” conditions submitted to cycles and secondly in “stress swelling” conditions. These studies lead to the determination of their swelling capacity and of resulting swelling pressures. Afterwards, the materials are examined from the textural point of view. The study with the help of the S.E.M. allowed to point out:

—the evolution of textures and their role in the initiation of the changes which affected the materials.

—the role of minor minerals such as pyrite, which contribute after oxidation to the degradation of clayey minerals and consequently to the evolution of textures which finally lead to a decay of mechanical characteristics.

     

梦境中的空间 法国des Berges酒店及水疗中心

<正>Illhaeusern是阿尔萨斯一座只有600户的小村庄。它坐落在流淌着温柔小溪的河岸边上,拥有法国东边最美的景致。150年前,Haeberlin家族就是在这座乡村的边缘创建了著名的米其林三星饭店Auberge de l’Ill。从1967年保存下来的这家饭店已经成为阿尔萨斯法式传统烹饪的重要遗产。现如今,这座米其林三星酒店分别由Marc Haeberlin负责厨房,他的妹     

Isotopenphysikalische Beiträge zur Beurteilung des Grundwasserschutzes im Buntsandstein

The complex application of isotope physical measuring methods together with model calculations for groundwater flow and hydrochemistry is helpful to estimate groundwater vulnerability. Thereby Tritium is used as a natural tracer of local groundwater input indicating a possible groundwater vulnerability, and the far-reaching, long-term groundwater migration is derived from Carbon-14 ages of dissolved inorganic carbon. For the case “double-porosity aquifer (Finne Bunter Sandstone, Saxonia-Anhalt)” the derivation of hydrogeological parameters as groundwater recharge, groundwater flow and the water exchange rate of an aquifer is demonstrated. Especially information on the groundwater vulnerability can be obtained without any real groundwater contamination.     

Herkunft der Salinit?t in Tiefenw?ssern des Grundgebirges – unter besonderer Berücksichtigung der Kristallinw?sser des Schwarzwaldes

Die Herkunft der Salinit?t in Grundgebirgsw?ssern wird in der internationalen Literatur heftig diskutiert. Für eine Anreicherung von Chlorid gibt es mehrere M?glichkeiten: Herkunft aus dem Gestein (Mineralgitter, Fluideinschlüsse, Korngrenzen) aus benachbarten salinaren Ablagerungen, aus einer Intrusion von Meerwasser. Anhand der Cl/Br-Systematik wird gezeigt, dass die hohe Salinit?t der Thermalw?sser des Schwarzwaldkristallins im Gegensatz zu anderen Kristallinw?ssern genetisch haupts?chlich auf einer Intrusion von Meerwasser beruht. Ein Eintrag aus salinaren Ablagerungen des Terti?r im Oberrheingraben oder aus dem Muschelkalk kann ausgeschlossen werden. Die marine Herkunft belegen auch die molaren Verh?ltnisse von Na und Cl, die Beziehung zwischen Na bzw. Cl und TDS im Vergleich zur Meerwasserverdünnungslinie. Einen entscheidenden Beitrag zur Wasserchemie aller Grundgebirgsw?sser liefert die Verwitterung von Plagioklas, insbesondere seiner vergleichsweise gut l?slichen Anorthitkomponenten. Zum Chemismus der Grundgebirgsw?sser tragen weiterhin die Verwitterung von Biotit mit Freisetzung von Li, F und K sowie die Wechselwirkung des Wassers mit K-Feldspat bei.     

Herkunft der Salinität in Tiefenwässern des Grundgebirges – unter besonderer Berücksichtigung der Kristallinwässer des Schwarzwaldes

Deep groundwater in fractured crystalline basement has been reported from deep mines and scientific wells. Highly saline brines have been described from several km depth in the continental basement worldwide. The origin of salinity is unknown and many different possibilities have been presented ( Emmermann et al. 1995, Pauwels et al. 1993, Edmunds &;: Savage 1991, Frape &;: Fritz 1987, Kozlovsky 1984, Banks et al. 1996, Stober 1986, 1995, Kanz 1987, Stober &; Bucher 1999). We compare the compositional evolution of deep waters in the Black Forest basements, SW-Germany, with those of other deep crystalline waters and use the halogen systematics (e. g. Cl/Br ratios) and other parameters of the waters to deduce the origin of their salinity. In teh Black Forest the composition of deep thermal waters results from chemical interaction of surface water with the rock matrix and from mixing of the reacted water with stagnant saline deep water of marine origin.     

Fallbeispiel Kluftgrundwasserleiter – Charakterisierung eines Grundwasserleiters im Rotliegendsandstein des Saar-Nahe-Beckens

Grundwasser - Das vorliegende Fallbeispiel führt unterschiedliche Feld- und Labormethoden zusammen und zeigt, wie für einen Standort in einem Kluftgrundwasserleiter die Kombination...     

Construction d'habitations dans des zones exposées au vent

Cet article traite du choix de I'emplacement, de la conception et de la construction d'habitations dans trois pays en voie de développement et qui sont, parfois, soumis à des vents violents. II est extrait d'un rapport établi il y a un an environ pour le Service Fédéral de Technologie de la Construction du National Bureau of Standards des Etats-Unis.