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marble filler (of a 1:2 mass ratio) [ 5 , 6 ]. Owing to superior water-reduction capabilities of these admixtures, the workability of the fresh mixes is improved, but it is possible to increase the amount of fine particles [ 6 – 8 ]. As a result, the

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Authors: E. Plevová, A. Kožušníková, L. Vaculíková and G. Simha Martynková

Abstract  

The definition as well as prediction of rock thermal behavior seems to be a quite difficult problem significantly effected by rock composition and structure. Temperature increase causes various changes of rock material (such as decomposition, oxidation, phase and polymorphic transformation, etc.). These changes are connected to thermal expansion with following appearance of tensions and cracks in minerals and rock structure. After consequential temperature decrease, developed tensions and cracks still influence the process. This study presents the application of thermogravimetric analysis, differential thermal analysis and thermomechanical analysis in characterization of selected marble thermal behavior. The texture and morphological orientation of calcite grains for marble samples was determined by optical microscopy. FTIR spectroscopy application along with X-ray diffraction (XRD) extended data about mineralogical composition. According to optical microscopy, the calcite grains show marked morphological anisotropy in one direction for some samples. Therefore, the thermal expansion had to be measured in three different (perpendicular to each other) directions. It is evident, that the effect of temperature on the final marble properties depends not only on mineralogical composition, but also on structure, texture and morphological orientation of grains. All these facts significantly influence the interpretation of differences in various marble thermal behavior.

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Abstract  

We present measurements of Thermoluminescence (TL) from Greek marble quarried at Paros, Naxos, Pendeli, Hymitos, Thassos, which have been known since ancient times. The results concern i) the solar bleaching of TL, ii) the solar transmission through marble thicknesses up to 16 mm, and iii) the implications for potential dating of ancient carved marble monuments/objects. The bleaching rate for marbles is very fast during the first hour of exposure. The solar penetration is at least 35 mm for long exposures. Beyond the 2 mm marble slab for exposure times 90–120 hours of sunshine, the residual bleached TL level is not reached. The bleached TL reaches a plateau which serves as the “zero time” upon which the archaeological TL dose subsequently builds up and gives the age of a marble monument.

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Authors: M. Carmo Freitas, L. Moens, P. De Paepe and J. Seabra E Barros

Abstract  

A 7 kg stone of a Carrara marble was reduced to grains smaller than 100 m, mixed and homogeneized in order to prepare a marble reference material. The homogeneity was tested for 16 elements by instrumental neutron activation analysis (INAA). Through a one-way analysis of variance based on several analyses of each of 15 bottles and within the same bottle, it was concluded that the inter-bottle heterogeneity is not greater than the intra-bottle heterogeneity. Results on the concentration of major and trace elements in the marble reference material, obtained by different laboratories and different techniques, are given. The limestone certified reference material KALKSTEIN KH was used to evaluate measurement accuracy, to intercalibrate laboratories, and to provide compatibility of measurement data.

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Abstract  

Marble samples from major Italian quarries and from the Como Cathedral were analyzed for their trace element content, which is indicative of their provenance. Ca, Sc, Cr, Mn, Fe, Co, Rb, Sb, Cs, Ba, La, Ce, Sm, Eu, Gd, Ho, Tm, Yb, Lu, Hf, Th and U elements were determined by neutron activation analysis. Results as well as their precision and accuracy are presented and discussed. Data treatment has allowed to characterize the marble quarries on the basis of their trace element content, to identify the provenance of the marble used in the Como Cathedral and to show differences in the element distribution of new and weathered marble samples from the same quarry.

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Unterwurzacher , Michael – Obojes , Ulrich : White marble from Laas (Lasa), South Tyrol – its occurrence, use and petrographic-isotopical characterisation . Austrian Journal of Earth Sciences 105 ( 2012 ) 1 . 26 – 37 . Utalvány

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Authors: K. H. Friolo, A. S. Ray, B. H. Stuart and P. S. Thomas

Summary Many of Sydney’s heritage buildings and monuments were built as a result of the first European settlement in the 1800s. These buildings not only display the richness of the Australian culture, but also capture the architectural and historical values of its past. Although many of these buildings still appear to be strong and sound, many signs of deterioration have been detected in recent years. Conservators from various disciplines such as science, architecture and engineering are working closely together to develop suitable solutions to stop or at least slow down the degradation process of these precious buildings. This study demonstrates the usefulness of thermal analysis in determining the weathering mechanisms of marble and sandstone taken from two of Sydney’s landmarks, the Captain Arthur Phillips Monument at Sydney’s Botanic Gardens and Sydney’s St Mary’s Cathedral. This paper reports the findings of the weathering behaviours of both marble and sandstone samples determined using thermal analysis techniques.

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Authors: L. Moens, P. Roos, J. De Rudder, J. Hoste, P. De Paepe, J. Van Hende, R. Marechal and M. Waelkens

Abstract  

In 94 marble samples from 4 quarry districts in Italy (Carrara) and Turkey (Proconnesus, Dokimeion, Usak), minor and trace elements were determined by instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS). The maximum size of the calcite grains (MGS) of the rocks was measured in thin section. For 16 elements considered in this work, the concentration ranges show important inter-district overlaps; this also applies to the maximum grain size. However, the application of cluster analysis, using selected attributes, allows one to discriminate every pair of districts; 90 samples are classified correctly in all classification dendrograms.

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Authors: S. Meloni, M. Oddone, N. Genova, V. Crespi, E. Mello, G. Tanda, C. Arias, M. Buonamici and A. Berzero

Abstract  

The development of a trace element fingerprint as obtained by trace element determination and data reduction has been successfully applied to clear out correlations and similarities among objects of archaeological interest. In the present paper instrumental neutron activation analysis and statistical data treatment were used to solve two archaeological question: (1) the search of white marble quarries which Etruscans were used to exploit to manufacture monuments and sculptures; (2) the search of similarity, and possibly of provenence, among pottery fragemets excavated in Sardinia and belonging to the eneolithic period. Trace element matrices are presented and discussed. Data treament, such as rare-earth element pattern and pattern recognition procedures, is reported and discussed.

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Abstract  

The interaction of Greek dolomitic marble (from Thassos island, northern Greece) with Co2+, Cd2+, Pb2+ and Cr3+ containing aqueous solutions was studied by characterizing the surface of the solid experimental samples, using a combination of spectroscopic, microscopic, and diffraction techniques (RBS, XPS, SEM-EDS, FT-IR, powder-XRD). The obtained results indicated a considerable Cd2+ and Co2+ sorption on the dissolved surface of the carbonate substrate, whereas, under the same experimental conditions, the Pb2+ and Cr3+ interaction is more intense leading to extended overgrowth of crystalline Pb2+ carbonates and massive surface precipitation of amorphous Cr3+ hydroxide/oxyhydroxide.

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