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Derombise G.,Laboratoire Regional Des Ponts Et Chaussees Of Nancy | Vouyovitch Van Schoors L.,IFSTTAR | Klop E.A.,Teijin Aramid B.V. | Schotman A.H.M.,Teijin Aramid B.V. | And 2 more authors.
Journal of Materials Science | Year: 2012

Aramid fibres are high-performance materials proposed in geotextiles for alkaline ground reinforcement. To study their durability in such environments, accelerated ageing has been carried out at pH 9 and at pH 11 for up to one and a half years. First, the lateral and longitudinal crystallite sizes have been determined before and after ageing under these conditions by Wide-Angle X-ray diffraction. Next, the tensile fracture surfaces have been observed after different ageing times by scanning electron microscopy. Finally, molecular weight changes have been evaluated by size exclusion chromatography. This study highlights the dependence of structural changes on the ageing conditions. A structural degradation scheme is proposed. © 2011 Springer Science+Business Media, LLC. Source

Suc J.-P.,CNRS Institute of Earth Sciences | Gillet H.,University of Bordeaux 1 | Cagatay M.N.,Technical University of Istanbul | Popescu S.-M.,GeoBioStratData.Consulting | And 13 more authors.
Marine and Petroleum Geology | Year: 2015

The two sides of the Strandja Sill show a highly discontinuous stratigraphic succession since the Late Oligocene. This area, together with the Sea of Marmara Basin, is usually proposed as the gateway for the Paratethyan freshwaters and organisms that constituted the Lago Mare facies in the Mediterranean Sea during the Messinian Salinity Crisis (MSC). Our investigations involving new field observations and datings, together with previous studies, suggest that the sill has possibly experienced such a connection at around 8. Ma, i.e. significantly before the crisis. The proposal of a sea-level drop of the Black Sea before 7. Ma is not supported by our data on dinoflagellate cysts. Consistency of calcareous nannofossil succession at DSDP Site 380 is reinforced, allowing to reassert that subaerial erosion impacted both the southwestern Black Sea and the central Marmara - Dardanelles area during the peak of the MSC. At that time, this region was crossed by two oppositely directed fluvial networks, further supporting the absence of a marine gateway through the Strandja Sill. It is concluded that none of the Lago Mare events recorded in the Mediterranean during the MSC were the consequence of the passage of Paratethyan waters and organisms through this area. In the Black Sea, the well-dated Messinian fluvial erosion can be followed offshore. The overlying prograding deltaic deposits attest to a fast marine reflooding after the crisis. This constitutes a comprehensive erosion - sedimentation model in an area intensively explored for hydrocarbons. © 2015 Elsevier Ltd. Source

Dumoulin J.,Ifsttar Institute Francais Des Science Technologies Des Transports Of Lamenagement Et Des Reseaux | Ibos L.,University Paris Est Creteil | Marchetti M.,Laboratoire Regional Des Ponts Et Chaussees Of Nancy | Mazioud A.,University Paris Est Creteil
European Journal of Environmental and Civil Engineering | Year: 2010

In this paper, Pulse Thermography analysis was applied to detect non emergent defects in asphalt concrete used for road pavements. Experimental and numerical experimentations were run on this specific heterogeneous material. Only experimental data acquired with an un-cooled microbolometer camera (less sensitive than a cooled one) were used. Data were processed using a semi-infinite heat transfer model in order to determine the depth of the defects. At last, a discussion on the influence of performances of the IR camera employed versus potential detection of subsurface defects is given in correlation with the investigated domain of pavement materials. © 2011 Lavoisier, Paris. Source

Do Couto D.,CNRS Paris Institute of Earth Sciences | Do Couto D.,Total S.A. | Popescu S.-M.,GeoBioStratData.Consulting | Suc J.-P.,CNRS Paris Institute of Earth Sciences | And 7 more authors.
Marine and Petroleum Geology | Year: 2014

This paper provides a new environmental, sedimentological and stratigraphic context of the Lago Mare deposits from the North Alboran region and clarifies their chronologic location with respect to the Messinian Salinity Crisis. We present new micropalaeontological data (dinoflagellate cysts, calcareous nannoplankton, planktonic foraminifers), correlated with field observations and offshore seismic interpretations. We show that the Lago Mare event known in three onshore localities (Río Mendelín near Malaga, Zorreras near Sorbas, Gafares near Níjar) follows the marine reflooding of the Mediterranean Basin which ended the Messinian Salinity Crisis. Chronologically, these Lago Mare deposits last from the latest Messinian to the early Zanclean. In fact, the first influx of Paratethyan organisms is revealed by the dinoflagellate cyst record from near Malaga within a Gilbert-type fan delta overlying the Messinian Erosional Surface. Invading molluscs and/or ostracods may have persisted in lagoonal coastal areas more or less affected by discontinuous marine influxes (Sorbas and Níjar). The Malaga area is convenient for a palaeogeographic and sedimentary reconstruction which shows the prevalent forcing of sea-level changes during the time-interval 5.600-5.332Ma at the difference of the usually solicited prevalent tectonics. The studied Lago Mare event is the third episode resulting in such a palaeobiological assemblage in the Mediterranean region and corresponds to the final two-way water exchange at high sea level between the Mediterranean and the former Paratethys. It documents the onset of the modern marine circulation in the Mediterranean after the reflooding ending the Messinian Salinity Crisis. © 2014 Elsevier Ltd. Source

Do Couto D.,University of Geneva | Popescu S.-M.,GeoBioStratData.Consulting | Suc J.-P.,CNRS Institute of Earth Sciences | Melinte-Dobrinescu M.C.,Romanian National Institute of Marine Geology and Geoecology GeoEcoMar | And 6 more authors.
Marine and Petroleum Geology | Year: 2015

The marine context of the Lago Mare deposit near Malaga has received agreement as well as its ascription to the third Lago Mare event of Clauzon et al. (2005). This deposit is not a "transitional unit towards normal marine conditions" but followed the marine reflooding of the Mediterranean Basin, allowing the connection with the Dacic Basin (Eastern Paratethys). We show that this Lago Mare event did not result from a climatic change leading to a dilution episode but from a high sea-level connection. Different interpretations on the respective effects of tectonics and eustatism on the sedimentary archives linked to the Messinian Salinity Crisis (MSC) are once more debated. They depend on (1) the duration assigned to the MSC and its subdivisions, (2) the amplitude of the successive sea level variations, and at last (3) the dimensional (local or regional) view of the MSC. Such discrepancies concern subsidiary matters which cannot mask first order facts and progresses in their knowledge. © 2014 Elsevier Ltd. Source

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