characterization studies on cement ...geo.geoscienze.unipd.it/sites/default/files/abstract...

Scuola di Dottorato in Scienze della Terra,Dipartimento di Geoscienze, Università degli Studi di Padova – A.A. 2010-2011

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CHARACTERIZATION STUDIES ON CEMENT CONGLOMERATES FROM HISTORICREINFORCED CONCRETE STRUCTURES

Ph.D. candidate: MICHELE SECCOTutors: Prof. GILBERTO ARTIOLI, Prof. CLAUDIO MAZZOLI

Cycle: XXIV

Abstract

One and a half century after its invention, the reinforced concrete is nowadays considered a cultural heritage material,being the structural core of the 20th century contemporary architecture. The characterization of this heterogeneous artefacthas been for decades exclusive competence of structural engineers, but, over the last fifteen years, it has become one of themain fields of study of material scientists, due to its mineralogical, textural and chemical complexity and high susceptibility tothe action of external chemical-physical degrading agents.

This research project is aimed at the multianalytical characterization of cement conglomerates from five historicalstructures located in north-eastern Italy and built between the end of the 19th and the middle of the 20th century, payingattention to the determination of the original mix designs, to the study of their conservation state and to the development ofnovel medium invasive analytical techniques.

The materials were first of all characterized according to a multianalytical approach, starting from the petrographiccharacterization of the conglomerates according to a custom-modified version of ASTM C856 standard and integrating thepetrographic data with mineralogical analyses by XRPD and microstructural-microchemical analyses by SEM-EDS. Thisclassic approach was only the starting point and the crosscheck for the quantitative reconstruction of concretes' mix designs,performed through a newly-developed multiscale image analysis technique; the novel approach proved to be extremelyreliable to fully characterize these heterogeneous and poorly standardized materials. Finally, an accurate study of theconservation state and degradation phenomena acting on the materials was performed by means of petrographic, XRPD andSEM-EDS analyses, paying particular attention to the characterization of the newly described synergic sulphate-phosphateattack, investigated also by synchrotron micro-diffraction, in situ XRPD studies using a diffractometer equipped with a hotchamber, thermal analyses, ICP-OES, FT-IR spectroscopy and thermodynamic modelling.

1. The structures: historical background, architectural features and sampling strategies

The construction time of the five buildings spans over a wide chronological period, comprisedbetween the last decade of the 19th century and the 1960s. They all belong to the first era of reinforcedconcrete production, characterized by the lack of plasticizers and water reducing admixtures in the mixes,consistency of the pastes below S4, project of the mixes according to prescribed dosages and not toperformance criteria and prevalence of the in situ construction of the reinforced concrete structuralelements over the use of prefabricated modules. The studied buildings are described as follows: North wing of the Carraresi Castle (Padova). Originally built between the 13th and 14th century, the

building was heavily modified between the end of the 19th century and the middle of the 20th centuryafter its conversion to prison. Reinforced concrete elements were introduced in the original structurein three distinct constructive phases: a first one at the end of the 19th century according to theHennebique construction method, a second one during the 1920s and the last one during the 1950s;

Victory Monument (Bolzano). Designed by Marcello Piacentini in 1926 and built during the course of1929, the Victory Monument is nowadays considered a masterpiece of fascist architecture. Inspired byRoman triumphal arches, the structure stands on a concrete strip foundation. The substructure of thepodium is constituted by non-reinforced concrete walls, sustaining a series of reinforced concreteslabs and beams forming the stairway and a non-reinforced concrete slab forming a central vault;

Former Zweifel embroidery plant (San Giovanni Lupatoto, Verona). Originally built in 1926, thestructure was raised in 1964 with the construction of a great hall inspired to Pierluigi Nervi concreteshells, made with both in situ produced and prefabricated elements. The building was interested in2008 by a severe structural failure, which caused the collapse of a wide area of the great hall;

“Ex Agrimont” area (Marghera, Venice). The industrial plant was founded in 1927 for the productionof fertilizers. During the 1950s a great reinforced concrete structure was built (C3 building),constituted by in situ prefabricated structural arches. The complex is currently under restoration;


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“Ex Foro Boario” (Padova). Designed by Giuseppe Davanzo and characterized by an extremelyinnovative design, the structure was built in 1968 and is made of prestressed and prefabricatedreinforced concrete slabs sustained by in situ-produced multiple concrete columns.The study was focused only on the characterization of the in situ produced concrete elements, being

the most susceptible to problems correlated to non standardized production protocols. According to thestructural nature of the buildings, different elements were sampled (slabs, walls, columns, arches andbeams). Accurate surveys were performed prior to concrete sampling, to minimize the invasiveness ofsampling operations. When possible, concrete samples were taken from already detached portions or fromscarifications residuals. Micro-cores for petrographic examinations were also extracted by means of awater-lubricated hollow tip drill. Large concrete cores, necessary both for the compression strength testsand the mix designs reconstructions, were extracted by means of a water-lubricated concrete core drill.Prior to perforation, the position of the structural elements with a low bending moment, shear and axialforce values was chosen and then a superficial scan by means of magnetic scanner was performed, toavoid damage to the rebars.

2. The classic approach: multianalytical characterization of the concretes

The textural and minero-petrographic characteristics of the concretes were determined by integratingthe analytical results of the petrographic examination according to ASTM C856 standard with themineralogical profiles obtained by XRPD and the microstructural and microchemical featuresinvestigated by SEM-EDS and chemical mapping.

The materials are characterized by heterogeneous volumetric proportions between inert fraction andcement matrix, both between the various structures and the various structural elements of each structure.High cement dosages are generally observable for structural elements built to withstand flexural stresses(e.g. beams and arches), with the exception of the central arches of the former Zweifel Embroidery plant,which show a marked cement underdosage.

The petrographic and morphological nature of the inert fractions indicates for all the studied structuresa local supply of the aggregate from adjacent alluvial deposits and river beds . The concretes of the NorthWing of the Carraresi Castle, the Ex Agrimont Area and the Ex Foro Boario are characterized by a coarsefraction mainly constituted by carbonate rocks, with prevalence of dolostones over limestones, while it ispossible to observe an enrichment in siliceous clasts in the fine fraction. The concretes of the formerZweifel embroidery plant differentiate from the previous ones, being constituted by an inert fractionalmost entirely composed of carbonate rocks as regards the coarse aggregate, with prevalence of micriticand bioclastic limestones over dolostones. Finally, the concretes of the Victory Monument are made withan inert fraction totally constituted by clasts of volcanic and metamorphic rocks, with prevalence ofignimbrites and quartzites. The maximum dimensions of the aggregate are generally related to thestructural elements, being greater for beams and walls with respect to slabs and columns. As regards thegranulometric distribution of the inert fractions, it is possible to observe an absence of design of thegranulometric curves for the older concretes, both in terms of maximum packing (Fuller & Thompsoncurve [1]) and maximum workability (Bolomey curve [1]), with frequent enrichment in medium andcoarse sand and coarse gravel. A good accordance with the ideal Bolomey curve is observable for the ExAgrimont Area and ex Foro Boario concretes only.

The density of the cement matrices varies according to each single structure and the type of structuralelements; generally, the most recent structures show a denser matrix, with lower capillary porosity,indicating lower cement ratios of the fresh conglomerates. Moreover, beams and columns show a lowerdegree of microcracking with respect to the other structural elements. The degree of hydration of thecement paste is generally high with limited permanence of residual clinker grains. Still, it is possible toobserve the presence of C2S, C3S and C4AF in the finer fractions of the materials. The relict clinkergrains generally have dimensions of 30-50 µm, with rare particles of 80-100 µm in the older concretesonly. Microanalyses on the grains indicated a total reaction of C3S and an high degree of reaction of C2Salso, while the interstitial phase is frequently totally unreacted.


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The voids network is equally widely heterogeneous according to the different structures and elements.A prevalence of millimetric entrapped air voids/water voids over submillimetric entrained air voids isobservable in the concretes of the second constructive phase of the North Wing of The Carraresi castle, aswell as in the concretes of the wall of the Victory Monument: these features indicate an inadequate degreeof compaction of the fresh conglomerate. The concretes of the arches of the former Zweifel embroideryplant are characterized by an anomalous presence of large entrapped air voids, mainly due to theinadequate volumetric proportions of the constituents. A prevalence of entrained air voids is observable inthe concretes of Ex Agrimont Area and Ex Foro Boario.

3. A novel approach: reconstruction of concretes mix designs through multiscale image analysis

The analytical results obtained with the previously described multianalytical protocol allowed anaccurate characterization of the analyzed materials, but still qualitative, in particular as regards thedetermination of several parameters, fundamental for the reconstruction of the original mix designs (e.g.water/cement ratio, cement/aggregate ratio, granulometric distribution curve of the inert fraction). At thestate of the art these characteristics are studied through manual point-count methodologies, such as thoseexplained in ASTM C 457 standard, with great limitations to the subjectivity of the analyses and to thefact that they are highly time-consuming. In this respect, several studies [2] proved the efficacy of digitalimage analysis to obtain an objective and unbiased volumetric and morphological estimation of concretepore network, without extending the technique to the characterization of all concrete constituents. One ofthe main objectives of this research project is the development of a valid and multiscale protocol ofsample preparation, image acquisition, and analysis in order to fully and quantitatively reconstruct mixdesigns of the studied historical concretes. The study was performed on the 26 structural elements fromwhich at least a large core for compression tests was extracted.

The macroscale image analysis was performed on several finely polished concrete slabs sawn fromthe cores at a distance greater than 100 mm from the external surface, to avoid areas altered by externaldegrading agents. To enhance the visibility of the macro-voids, a protocol of vacuum impregnation of theporosity by a green dyed epoxy resin was developed. Moreover, micro-voids were enhanced by fillingthem with a micronized powder of synthetic eskolaite, characterized by a green colour similar to the oneof the resin. The treated surfaces were scanned in 24-bit RGB color through an Epson V750 PRO flatbedscanner at a 3600x3600 dpi (8x8 µm) optical resolution. Then, to enhance cement matrices, the surfaceswere subject to an acid attack with a solution of 3% tartaric acid-3% tannic acid [3], which selectivelystained the hardened paste only, and re-scanned at the same resolution with a fluid mount technique. Afteran accurate registration, the six channels of the images were merged in a multi-channel composite image,analyzed with a multispectral software (ENVI 4.7) to segment the three main volumetric components ofconcretes (cement matrix, aggregate and voids). Excellent results were obtained by applying an algorithmof maximum likelihood to defined classes, described by an adequate number of training pixels. Thevolumetric estimations obtained by the segmentation procedure, calculated with ImageJ software, werecompared to the ones obtained performing a manual point count on the same samples: the data resulted tobe fully comparable, confirming the reliability of the image analysis procedure.

The macroscale data were extended at the microscale performing image analysis routines on severalimages obtained by SEM imaging and EDS mapping on samples in thin section. The segmentation wasobtained with both a custom-formulated BSE-SE images merging technique and a multi-elemental imageanalysis procedure, performed on multi-channel composite images created from the elemental maps andanalyzed with a multispectral software (ENVI 4.7). The latter technique allowed not only thesegmentation of the three main concrete constituents, but also a quantitative determination of themineralogical nature of the fine aggregate.

Considering the direct relation between capillary porosity and water/cement ratio [4], the latter wasdetermined on the studied concretes by means of automated image analysis on high magnification BSEimages of the cement matrices, using long-cured CEM I standard samples to extrapolate the regressionfunctions between the two parameters.


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The conversion of the volumetric percentages into absolute weight fractions was performed byestimating the densities of the solid components of concretes. Sand densities were determined by thequantitative determination of their mineralogical profiles obtained by multi-elemental image analysis,while gravel densities were estimated considering their petrographic nature. Cement paste densities weredetermined through the extrapolation of the regression function between their values and water/cementratios, using long-cured CEM I standard samples as reference, analyzed both by helium pycnometry andthermogravimetry. The weight quantities of anhydrous cement on the original mixes were estimatedconsidering the amount of structural water on the hardened cement pastes, strictly related to water/cementratios, as determined by thermogravimetry on standard samples.

Finally, the granulometric distributions of the inert fractions were reconstructed by image analysis,integrating the morphological data of the aggregate particles segmented at different scales, and the resultswere compared with the corresponding Fuller & Thompson and Bolomey curves, to check the accuracy ofthe initial aggregate proportioning.

The data obtained from the multiscale image analysis procedure resulted to be fully comparable withthe ones obtained from the multianalytical study, allowing the integration and quantitative confirmationof the results. Generally, a lack of accurate mix design for the older concretes has been observed, inaccordance with the production of the conglomerates according to prescribed dosages and not toperformance criteria. The correspondence between experimental granulometric curves and referenceBolomey curves is satisfied especially in the most recent structures, in particular on Ex Foro Boarioconcretes, whereas in the older structures strong enrichments in coarse gravel and/or coarse and mediumsand are frequent (figure 1). Moreover, it was observed that high compression strength values wereobtained even in the oldest structures by using high cement dosages, whereas low compression strengthvalues are strictly correlated with anomalous porosities, due to both excessive water/cement ratios andinadequate compaction procedures. In the most extreme cases, combinations of wrong constituentsproportioning, low cement dosages, excessive water/cement ratios and porosities and bad granulometricdistributions led to extremely poor mechanical properties, responsible for more or less accentuatestructural failures (e.g. former Zweifel embroidery plant).

4. The study of concrete degradation

The alteration phenomena acting on the concrete elements of the studied structures were studiedaccording to a multianalytical approach articulated in a preliminary petrographic study, integrated byprofile XRPD analyses on the finer fractions of the materials and SEM-EDS analyses both on massiveand thin section samples.

All the materials were interested by carbonation of the cement matrices. The degree of alterationresulted to be strongly dependent to the textural characteristics of the materials and the environmentalconditions to which they were exposed. Generally, the carbonation is limited to the cortical portions ofthe concretes, with maximum penetration of the front located in the concrete outer cover and permanenceof the alkaline environment in the core. The excessive porosity of some structural elements, the highwater percolation and relative humidity excursions, or a combination of both factors, caused anomalousdevelopment of the degradation in some cases, with consequent oxidation of the rebars. As regards theNorth Wing of the Carraresi Castle, the ground floor beams underwent total carbonation due to the highporosity, while the third floor slab resulted to be totally carbonated due to both the anomalous porosityand the exposition to massive water percolation due to the collapse of the roof. As regards the VictoryMonument, the massive water percolation and high relative humidity variations caused relevantcarbonation phenomena on the concrete samples of the walls only, characterized by high connectedmacroporosity. The alteration was so intensive as to cause the formation of metastable calcium carbonate(vaterite) in the matrices, often in framboidal aggregates, and to cause the formation of external concretestalactites. As regards the former Zweifel embroidery plant, the total carbonation was reached in the archconcretes only, characterized by extremely high porosity values.

All the concretes underwent alteration due to external sulphate attack. The degradation resulted to bein most cases limited to the cortical portions, and at an initial stage of secondary gypsum formation due to


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portlandite reaction with sulphates in pore solution, with limited formation of ettringite and thaumasite.High carbonation rates resulted to be a limiting factor for the development of this form of alteration,being a strong source of calcium hydroxide consumption. External sulphate attack resulted to beextremely diffuse in the "ex Agrimont" area concretes, with precipitation of high amounts of gypsum,ettringite and thaumasite even in the core of the materials: this is due to the high environmental pollutionrelated to the industrial area.

Chloride attack interested the "ex Agrimont" area concretes only, due to the proximity of the structureto the coastline and the consequent exposure to saltwater capillary rise and saline aerosols. The effects areformation of secondary Friedel's salts, due to the dissolution of hydrous calcium aluminates and reactionwith chloride-rich porewater, and pitting corrosion of the rebars, with precipitation of iron chlorides.

Alkali-silica reactions resulted to be widely diffused in the Victory Monument concretes, withformation of hydrous alkali-silica gels due to the reaction between amorphous silica of the aggregate andalkali ions in pore solution, leached from both the cement matrix and the volcanic glass of the ignimbritesconstituting the inert fraction. Microscopic observations show the widespread presence of stressed andstrongly corroded ignimbrite and microcrystalline quartz fragments with corrosion bends. Furthermore,the samples show many micro-cracks, mostly oriented perpendicularly to the concrete’s external surfaceand interconnected with each other by a network of random sub-micrometer cracks. The presence ofdiffuse ASR gel products is confirmed by EDS mapping of the altered matrices, highly enriched inpotassium in comparison to standard unaltered concretes.

The Victory Monument concretes are also characterized by superficial scaling due to saltcrystallization pressure development related to the formation of sodium sulphates, both anhydrous(thenardite) and hydrated (eugsterite and mirabilite). The development of these secondary phases, duringrapid and intense variations in relative humidity values and consequent wetting and drying cycles of thepore water, is due to the reaction between alkalis and sulphate in pore solution.

The concrete samples of the "ex Foro Boario" are interested by a rare form of alkali carbonatereaction which caused de-dolomitization phenomena on the dolostone clasts constituting the inertfraction, that are characterized by the presence of reaction rims with precipitation of secondary magnesiteat the interface with the surrounding matrix.

Besides these common forms of concrete alteration, a novel type of degradation was for the first timeobserved and described in the concrete samples of the "Ex Agrimont" area, the synergic sulphate-phosphate attack. This form of alteration, related to the interaction between sulphate-rich atmosphericmultipollutants and phosphate-ammonia-rich solutions leached from the fertilizers production plant, wasstudied through a profile multi-analytical approach consisting of a combination of optical microscopy,synchrotron-based micro-XRPD (performed at the µ-spot beamline of BESSY II light source) and SEM-EDS microanalysis. Moreover, the dehydration behaviour of the secondary phases was investigated on thesynthesized phases through in situ thermal XRPD and Rietveld refinement, thermal analyses, ICP-OES,FT-IR spectroscopy and SEM-EDS analyses. Finally, a thermodynamic alteration model was elaboratedusing PHREEQC2 software. The results suggest severe decalcification of the cement matrix andformation of secondary sulphates and phosphates according to a marked mineralogical and texturalzoning: I) gypsum, bassanite, anhydrite and ardealite in the superficial efflorescence; II) monetite in thesuperficial crusts; III) gypsum-brushite solid solution and ardealite in the external strata; IV) octacalciumphosphate and struvite in the intermediate layers; V) apatite and struvite in the inner altered portions. Theheterogeneous microstructural development of secondary phases was interpreted taking into account thedifferent source of sulphate and phosphate pollutants. Moreover, the permanence of apatite acidicprecursors in the external strata suggests that these portions were exposed to high acidity conditions,related to sulphuric acid formation in the pore water after reaction with sulphur dioxide, while thepresence of anhydrous calcium sulphates and phosphates suggest a progressive dehydration, possibly bysolar radiation warming of the solid solution end-members, i.e. gypsum and brushite-rich terms.


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Figure 1. Comparison between a low strength concrete (a, b, c: lateral wall of Victory Monument, Rck 10.05 MPa) and an highstrength concrete (d, e, f: column of "Ex Foro Boario", Rck 68.67 MPa). a, d) segmentation of cement matrix (cyan), aggregate

(magenta) and voids (yellow); cement dosages: 212.63 kg/m3 (lateral wall of Victory Monument), 330.31 kg/m3 (column of"Ex Foro Boario". b, e) retained aggregate fractions at the ASTM standard sieves and comparison with reference Bolomey

values. c, f) cumulative passing granulometric curves, in comparison with reference Bolomey curves.

References

[1] COLLEPARDI, M., COLLEPARDI, S. & TROLI, R. 2008. Mix design del calcestruzzo. Enco S.r.l.,Treviso.

[2] JAKOBSEN, U.H., PADE, C., THAULOW, N., BROWN, D., SAHU, S., MAGNUSSON, O., DEBUCK, S. & DE SCHUTTER, G. 2006. Automated air void analysis of hardened concrete – a RoundRobin study. Cement and Concrete Research, 36, 1444-1452.

[3] LINARES, L., LOPEZ-ATALAJA, M. & CHINCHON, S. 2009. Cement content determinationthrough selective stain in hardened concrete. Cement and Concrete Research, 39, 1105-1109.

[4] INGHAM, J. 2011. Geomaterials under the microscope. Manson Publishing, London.


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SUMMARY OF LAST YEAR’S ACTIVITIES

Courses:

MAZZOTTI, C., SURICO, F., FERRARI, G. & MARINO, R.: "Tecnologia del calcestruzzo", Auditorium Mapei, Milano.

Schools, workshops and congresses

10th International Conference on non-destructive investigations and microanaysis for the diagnostics and conservation ofcultural and environmental heritage, ART'11 , Firenze, IT, 13th-15th April 2011.

13th International Congress on the Chemistry of Cement, ICCC 2011, Madrid, ES, 3rd-8th July 2011.

XCVII Congresso Nazionale della Società Italiana di Fisica, SIF 2011, L'Aquila, IT, 26th-30th September 2011.

SAIE Concrete 2011, Bologna, IT, 4th-9th October 2011.

Communications:

ARTIOLI, G., CASARIN, F., DALLA BENETTA, M., DA PORTO, F., SECCO, M., & VALLUZZI, M.R. 2011. Restoration ofhistoric masonry structures damaged by the 2009 Abruzzo earthquake through injection grouts. 9th Australasian MasonryConference. 15th-18th February 2011, Queenstown (NZ).

SECCO, M., STIEVANIN, E., DA PORTO, F., MODENA, C., ARTIOLI, G. & MAZZOLI, C. 2011. Non destructive andmedium destructive analyses on an early 20th century reinforced concrete structure: the case study of the Victory Monument inBolzano. 10th International Conference on non-destructive investigations and microanalysis for the diagnostics andconservation of cultural and environmental heritage – ART ‘11, Firenze (IT).

SECCO, M., MARITAN, L., LAMPRONTI, G.I., ARTIOLI, G. & MAZZOLI, C. 2011. Degradation of reinforced concretesfrom industrial buildings caused by combined sulphate-phosphate attack. 13th International Congress on the Chemistry ofCement – ICCC 2011, Madrid (ES).

SECCO, M., ARTIOLI, G., DALLA BENETTA, M., DA PORTO, F., & COLETTI, C. 2011. Restoration of historic masonrystructures damaged by the 2009 Abruzzo earthquake: materials and methods. XCVII Congresso Nazionale della SocietàItaliana di Fisica – SIF 2011, L'Aquila, IT.

Posters:

MARITAN, L., WAKSMAN, Y., SECCO, M., LAMPRONTI, G.I. & MAZZOLI, C. 2011. Alteration of lead-glazed ware andamphorae from shipwrecks in the Black Sea (Ukraine). 11th European Meeting on Ancient Ceramics, EMAC 2011. 29th

September-1st October 2011, Natural History Museum, Vienna (AT).

MARITAN, L., SECCO, M. & MANTOVANI, V. 2011. The decorated Padan terra sigillata from Adria (north-eastern Italy):provenance and production technology. 11th European Meeting on Ancient Ceramics, EMAC 2011. 29th September-1st October2011, Natural History Museum, Vienna (AT).

Publications:

SECCO, M., MARITAN, L., MAZZOLI, C., LAMPRONTI, G.I., ZORZI, F., NODARI, L., RUSSO, U. & PESAVENTOMATTIOLI, S. 2011. Alteration processes of pottery in lagoon-like environments. Archaeometry, 53, 809-829.

ARTIOLI, G., CASARIN, F., DALLA BENETTA, M., DA PORTO, F., SECCO, M., & VALLUZZI, M.R. 2011. Restoration ofhistoric masonry structures damaged by the 2009 Abruzzo earthquake through injection grouts. In: Proceedings of the 9th

Australasian Masonry Conference. 15th-18th February 2011, Queenstown (NZ).


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SECCO, M., STIEVANIN, E., DA PORTO, F., MODENA, C., ARTIOLI, G. & MAZZOLI, C. 2011. Non destructive andmedium destructive analyses on an early 20th century reinforced concrete structure: the case study of the Victory Monument inBolzano. In: Proceedings of the 10th International Conference on non-destructive investigations and microanalysis for thediagnostics and conservation of cultural and environmental heritage – ART ‘11, Firenze.

SECCO, M., MARITAN, L., LAMPRONTI, G.I., ARTIOLI, G. & MAZZOLI, C. 2011. Degradation of reinforced concretesfrom industrial buildings caused by combined sulphate-phosphate attack. In: Proceedings of the 13th International Congress onthe Chemistry of Cement – ICCC, Madrid.

SECCO, M. 2011. Restoration of historic masonry structures damaged by the 2009 Abruzzo earthquake: materials andmethods. Il Nuovo Cimento C - Colloquia and communications in physics, in press.

STIEVANIN, E., DA PORTO, F., MODENA, C., SECCO, M. & ARTIOLI, G. 2011. Characterization studies on the reinforcedconcrete dome of the former General Market of Verona, built in 1929. In: Proceedings of the "Domes in the World"International Scientific Congress, Firenze.

Awards:

Award for the best communication at XCVII Congresso Nazionale della Società Italiana di Fisica, Sezione Vb "Fisica per iBeni Culturali".

Teaching activities:

Co-supervisor of bachelor degree thesis in Science and Technology for Cultural Heritage. Student: Elena Squizzato; title of thethesis: " Il degrado in ambiente di transizione: il caso delle ceramiche invetriate dall'affondamento di Novy Svet (Mar Nero) ".

Co-supervisor of bachelor degree thesis in Science and Technology for Cultural Heritage. Student: Vanessa Doulougeris; titleof the thesis: " Il degrado in ambiente di transizione: il caso delle anfore dall'affondamento di Novy Svet (Mar Nero) ".

Co-supervisor of bachelor degree thesis in Geological Science. Student: Federico Saporito; title of the thesis: "Studiosull'influenza dei minerali argillosi sul fenomeno franoso in località Gamba (Monte di Malo, VI)".

Co-supervisor of master degree thesis in Science and Technology for Archaeological and Artistic Heritage. Student: SilviaMadeddu; title of the thesis: "Caratterizzazione multi-analitica di conglomerati cementizi pertinenti a strutture storiche incemento armato".

Co-supervisor of bachelor degree thesis in Science and Technology for Cultural Heritage. Student: Alberto Zausa.

Co-supervisor of master degree thesis in Materials Science. Student: Riccardo Balzarin.

Field and experimental activities:

In situ non destructive and medium destructive analyses on reinforced concrete elements from late 19th – first 20th centurybuildings located in the Veneto and Trentino-Alto Adige regions, together with adequate sampling by means of core-holedrilling, local scarifications and superficial ablations. All analyses and sampling operations were performed in collaborationwith the Structural and Transportation Engineering Department of the University of Padova.

Petrographic, mineralogical, textural, microstructural and chemical analyses on the concrete samples taken during the fieldactivities by means of polarizing microscope and SEM observations, EDS microanalyses, XRPD analyses and image analysis.All analyses were performed at the Geosciences Department, University of Padova.

Microstructural, microchemical and minero-petrographic analyses by means of polarizing microscope and SEM observations,EDS microanalyses and XRPD analyses on samples of altered lead-glazed wares and amphorae from shipwrecks in the BlackSea (Ukraine). All analyses were performed at the Geosciences Department, University of Padova.

Characterization studies through minero-petrographic and microchemical-microstructural analyses by means of polarizingmicroscope and SEM observations, EDS microanalyses and XRPD analyses on historic mortars from San Pietro Apostolochurch (Onna, AQ). All analyses were performed at the Geosciences Department, University of Padova.


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Characterization studies through minero-petrographic and microchemical-microstructural analyses by means of polarizingmicroscope observations and XRPD analyses on historic mortars from San Domenico church (L'Aquila). All analyses wereperformed at the Geosciences Department, University of Padova.

Assessment of fire-damaged binders from Ex asilo Rossi (Schio, Vicenza) through microstructural, microchemical and minero-petrographic analyses by means of polarizing microscope and SEM observations, EDS microanalyses and XRPD analyses. Allanalyses were performed at the Geosciences Department, University of Padova.

Study of the influence of mineral composition of soils on the activation and progression of Monte di Malo landslide (VI) bymeans of XRPD analyses. All analyses were performed at the Geosciences Department, University of Padova.

Chemical-mineralogical and microstructural characterization of high-performance self-compacting reinforced concretemodules by means of polarizing microscope and SEM observations, EDS microanalyses, XRPD analyses, XRF analyses andmercury intrusion porosimetry. Optimization of mix designs for the improvement of the resistance to carbonatationphenomena.

Mechanical and chemical-physical tests on prefabricated self-compacting concrete elements for sewage waters according tostandard UNI EN 1917. Study of the resistance of concretes to the action of highly aggressive wastewaters, throughmineralogical and chemical profiling by XRPD and SEM-EDS analyses. The analyses were performed at the GeosciencesDepartment and at the Structural and Transportation Engineering Department, University of Padova.

Characterization studies through minero-petrographic and microchemical-microstructural analyses by means of polarizingmicroscope and SEM observations, EDS microanalyses and XRPD analyses on restoration plasters from a historic building inVerona. All analyses were performed at the Geosciences Department, University of Padova.

Petrographic, mineralogical, textural and microstructural analyses on concrete samples from a hangar of Fiumicino airport(Roma) by means of polarizing microscope and SEM observations, EDS microanalyses and XRPD analyses. The study wasaimed at determining the state of conservation of the structural materials. All analyses were performed at the GeosciencesDepartment, University of Padova.

Radiocarbon AMS dating on ancient mortars from three castle remains of different ages (Cuol di Ciastiel Castle, Late RomanEmpire, Pra di Got Castle, Early Middle Age, Sachuidic Castle, XII-XIII Century A.D.), located in the High Tagliamento riverValley (Udine, Italy). All analyses were performed at the CIRCE AMS laboratory, Second University of Naples (Caserta).

SUMMARY OF SECOND YEAR’S ACTIVITIES

Courses:

BOURGARIT, D.: “Archaeometallurgy at the Louvre laboratory: from Bronze Age copper smelting to Renaissance bronzestatues casting”, Dipartimento di Geoscienze, Università degli Studi di Padova.CALANDRUCCIO, E.: “Corso di Inglese parlato”, Dipartimento di Geoscienze, Università degli Studi di Padova.DALCONI, M. C.: “Mineralogia applicata ai minerali industriali”, Dipartimento di Geoscienze, Università degli Studi diPadova.MAZZOLI, C.: “Laboratorio di Microscopia”, Dipartimento di Geoscienze, Università degli Studi di Padova.NONAT, A.: “Generalities on cement and thermodynamics and kinetics of hydration”, Dipartimento di Geoscienze, Universitàdegli Studi di Padova.SALMASO, L. & CORAIN, L.: "Statistica applicata alla sperimentazione scientifica", Centro studi per l’Ambiente Alpino,San Vito di Cadore (BL).SCRIVENER, K.: "Mapei symposium on the cement chemistry", Auditorium Mapei, Milano.


Second UNESCO World Heritage Workshop on “Disaster Risk Reduction to Cultural Heritage”. Acre, Israel, 14th-17th

November 2009.

38th International Symposium on Archaeometry, ISA 2010, Tampa, FL, U.S.A., 10th-14th May 2010.


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The 20th General Meeting of the International Mineralogical Association, IMA 2010, Budapest, HU, 21st-27th August 2010.

SEM and Microanalysis in the Study of Historical Technology, Materials and Conservation, SEM 2010, London, GB, 9th-10th

September 2010.

2nd Historic Mortars Conference and RILEM TC 203-RHM “Repair Mortars for Historic Masonry” Final Workshop, Prague,CZ, 22nd-24th September 2010.

Communications:

SECCO, M., MARITAN, L., LAMPRONTI, G.I., MAZZOLI, C., & ARTIOLI, G. 2010. Crystallization of secondary sulphateand phosphate phases in cementitious conglomerates exposed to polluted environments. The 20th General Meeting of theInternational Mineralogical Association, IMA 2010. 21st-27th August 2010, Danube Riverside Campus (Lágymányos) of theEötvös University, Budapest (HU).

Posters:

SECCO, M., ARTIOLI, G., MAZZOLI, C., GELICHI, S., CIANCIOSI, A. & PIUZZI, F. 2010. Archaeometrical studies onmortars from the Sachuidic Castle (Forni di Sopra, North-eastern Italy): a tool for archaeological data interpretation. 38th

International Symposium on Archaeometry, ISA 2010. 10th-14th May 2010, University of South Florida, Tampa (FL, USA).

MARITAN, L., NODARI, L., THIELLA, V., SECCO, M., LAMPRONTI, G.I., RUSSO, U., MAZZOLI, C. & PESAVENTOMATTIOLI, S. 2009. Transitional environments and alteration processes: the case study of pottery from the Roman riverharbour of Corte Cavanella (Rovigo, North-eastern Italy). 38th International Symposium on Archaeometry, ISA 2010. 10th-14th

May 2010, University of South Florida, Tampa (FL, USA).

MARITAN, L., SECCO, M., MAZZOLI, C. & , ARTIOLI, G. 2010. Secondary phases in historical materials: a microstructuralapproach for interpreting correct sequences of crystallization. SEM and Microanalysis in the Study of Historical Technology,Materials and Conservation, SEM 2010. 9th-10th September 2010, British Museum, London (UK).

ARTIOLI, G., SECCO, M., MAZZOLI, C., COLETTI, C., VALLUZZI, M.R. & DA PORTO, F. 2010. Characterization ofstone masonry panels consolidated by injection of grouts in buildings damaged by the 2009 Abruzzo earthquake. 2nd HistoricMortars Conference and RILEM TC 203-RHM “Repair Mortars for Historic Masonry” Final Workshop. 22nd-24th September2010, Hotel Diplomat, Prague (CZ).

Publications:

SECCO, M., MARITAN, L., LAMPRONTI, G.I., MAZZOLI, C., & ARTIOLI, G. 2010. Crystallization of secondary sulphateand phosphate phases in cementitious conglomerates exposed to polluted environments. Acta Mineralogica-Petrographica,Abstract Series, 6, 65.

ARTIOLI, G., SECCO, M., MAZZOLI, C., COLETTI, C., VALLUZZI, M.R. & DA PORTO, F. 2010. Characterization ofstone masonry panels consolidated by injection of grouts in buildings damaged by the 2009 Abruzzo earthquake. In: Valek, J.,Groot, C. & Hughes, J.J. (ed.). Proceedings of the 2nd Historic Mortars Conference and RILEM TC 203-RHM “Repair Mortarsfor Historic Masonry” Final Workshop, 871-881. RILEM Publications, Bagneux.

MARITAN, L., SECCO, M., MAZZOLI, C. & , ARTIOLI, G. 2010. Secondary phases in historical materials: a microstructuralapproach for interpreting correct sequences of crystallization. In: Meeks, N. (ed.) Proceedings of the 1st conference “SEM andMicroanalysis in the Study of Historical Technology, Materials and Conservation, SEM 2010”. Archetype Publications,London. In press.


Teaching assistant: 2 hours, “Petrografia applicata ai materiali ceramici”, Laurea di primo livello in Scienze e Tecnologie per iBeni Culturali (2009/2010).

Teaching assistant: 4 hours, “Georisorse per i Beni Culturali”, Laurea specialistica in Scienze e Tecnologie per i BeniArcheologici ed Artistici (2009/2010).


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Co-supervisor of master degree thesis in Science and Technology for Archaeological and Artistic Heritage. Student: ChiaraColetti; title of the thesis: "Iniezioni compatibili per il consolidamento di murature danneggiate dal sisma di Abruzzo 2009:caratteristiche dei materiali strutturali e dei leganti".


In situ non destructive and medium destructive analyses on reinforced concrete elements from late 19th – first 20th centurybuildings located in the Veneto and Trentino-Alto Adige regions, together with adequate sampling by means of core-holedrilling, local scarifications and superficial ablations. All analyses and sampling operations were performed in collaborationwith the Structural and Transportation Engineering Department of the University of Padova.

Petrographic, mineralogical, textural, microstructural and chemical analyses on the concrete samples taken during the fieldactivities by means of polarizing microscope and SEM observations, EDS microanalyses, XRPD analyses and image analysis.All analyses were performed at the Geosciences Department, University of Padova.

Petrographic, mineralogical, textural and microstructural analyses on a concrete pavement from an industrial building(Villesse, Gorizia, Italy) by means of polarizing microscope observations and XRPD analyses. The study was aimed atdetermining the state of conservation of the structural substrate and the superficial coating. All analyses were performed at theGeosciences Department, University of Padova.

Study of the resistance of silica fume-additivated self compacting concretes to the action of highly aggressive wastewaters,trough mineralogical and chemical profiling by XRPD and SEM-EDS analyses. All analyses were performed at theGeosciences Department, University of Padova.

In situ samplings and archaeometrical studies by means of petrographic, microstructural, mineralogical and statistical analyseson ancient mortars from three castle remains of different ages (Cuol di Ciastiel Castle, Late Roman Empire, Pra di Got Castle,Early Middle Age, Sachuidic Castle, XII-XIII Century A.D.), located in the High Tagliamento river Valley (Udine, Italy). Allanalyses were performed at the Geosciences Department, University of Padova.

Archaeometrical studies by means of petrographic, microstructural, mineralogical and statistical analyses on ancient mortarsfrom the Caporiacco Castle (XI Century A.D.), located in Colloredo di Monte Albano (Udine, Italy). All analyses wereperformed at the Geosciences Department, University of Padova.

In situ samplings and characterization studies by means of petrographic, microstructural, mineralogical and microchemicalanalyses on hardened restoration grouts injected inside multi-leaf medieval sea walls of the Citadel of Acre, Israel. All analyseswere performed at the Geosciences Department, University of Padova.

Participation to a pilot project for the restoration of masonry walls from the towns of Onna, Tempera and Sant’EusanioForconese (L’Aquila, Italy), heavily damaged by the 2009 Abruzzo earthquake, by means of compatible injection grouts. Theproject was done in collaboration with the Structural and Transportation Engineering Department of the University of Padovaand several industrial partners (Mapei, Kerakoll, Tassullo, Basf). Several portions of multi-leaf stone masonry walls wereselected for carrying out experimental injection tests, planned and verified by means of non-destructive and destructivemultiscale characterization studies. In particular, the original mortars were fully characterized from the mechanic,petrographic, textural, mineralogical and chemical point of view, to choose the most suitable restoration products. Thecharacterization was carried out through compression strength tests, petrographic examinations, particle size distributionstudies, colorimetric measurements, XRPD analyses, microchemical and microstructural studies by SEM-EDS. The samemethodology was adopted to assess the compatibility of the chosen restoration products. The selected masonry portions werecharacterized by means of non-destructive sonic tests. The shear strength and deformability of some of the masonry walls wereevaluated by means of diagonal tests, carried out in the original – non-reinforced – state. The remaining masonry walls wereinjected with the selected grouts, and tested again by means of sonic and diagonal compression tests in the strengthened state,to assess the effectiveness of the interventions. Finally, after the destructive tests, the effectiveness of the selected restorationprotocols and materials on the microstructures was checked through optical and electronic microscopy on the interfacial zonesbetween the grout and the original constituents.

Microstructural, microchemical and minero-petrographic analyses on samples of Roman Terra Sigillata potteries found in thecity of Adria (Rovigo, Italy). All analyses were performed at the Geosciences Department, University of Padova.

Microstructural, microchemical and mineralogical analyses by XRPD and SEM-EDS on samples of Roman potteries found inthe site of Corte Cavanella (Loreo, Rovigo, Italy). Analyses were performed both at the Geosciences Department, University ofPadova and at the Chemical Sciences Department, University of Padova, in collaboration with Dr. Valentina Thiella, Dr. LaraMaritan, Dr. Luca Nodari and Prof. Umberto Russo, in order to understand the nature of various types of chromatic turnings.


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SUMMARY OF FIRST YEAR’S ACTIVITIES

Courses:

BOESSO, S.: “Introduzione alla biblioteca”, Dipartimento di Geoscienze, Università degli Studi di Padova.DALCONI, M. C.: “Mineralogia applicata ai minerali industriali”, Dipartimento di Geoscienze, Università degli Studi diPadova.FIORETTI, A., DI TORO, G. & ARTIOLI, G.: "Corso di comunicazione scientifica", Dipartimento di Geoscienze, Universitàdegli Studi di Padova.GLASSER, F.: “The materials science of Portland cement”, Dipartimento di Geoscienze, Università degli Studi di Padova.GULICK, L.: “Corso avanzato di Inglese”, Dipartimento di Geoscienze, Università degli Studi di Padova.MAZZOLI, C.: “Laboratorio di Microscopia”, Dipartimento di Geoscienze, Università degli Studi di Padova.PESARIN, F. & SALMASO, L.: "Statistica applicata alla sperimentaizone scientifica", Dipartimento di Ingegneria Meccanica,Università degli Studi di Padova.RASSU, A., VINANTE, C. & PRATICELLI, N.: “Introduzione a LinuX”, Dipartimento di Geoscienze, Università degli Studidi Padova.STUTZMAN, P. & BULLARD, J.: “Avanced course on cement characterization and modelling”, Dipartimento di Geoscienze,Università degli Studi di Padova.TEZA, G.: “Introduction to Matlab”, Dipartimento di Geoscienze, Università degli Studi di Padova.


X School on Synchrotron Radiation: Fundamentals, Methods and Applications. Duino (TS), Italy, 7th-18th September 2009.

Injection Grouts for the Conservation of Architectural Surfaces, Getty Conservation Institute, Los Angeles, CA, U.S.A., 2nd-3rd

November 2009.

Posters:

NODARI, L., MARITAN, L., SECCO, M., RUSSO, U., MAZZOLI, C. & PESAVENTO MATTIOLI, S. 2009. Alterationprocesses in lagoon environments: the case study of the Roman pottery from Aquileia and Olbia (Italy). 10th European Meetingon Ancient Ceramics, EMAC 2009. 10th-13th September 2009, British Museum, London (UK).

Publications:

MARITAN, L., SECCO, M., MAZZOLI, C., NODARI, L., RUSSO, U. & PESAVENTO MATTIOLI, S. (2009). Forme e fasidi alterazione dei materiali ceramici di Canale Anfora: implicazione nella ricostruzione delle condizioni dell’ambiente diseppellimento. In: Scotti Maselli, S., Pesavento Mattioli, S. (ed.). I materiali dal Canale Anfora di Aquileia. Editreg, Trieste.In press.

MARITAN, L., MAZZOLI, C., SECCO, M. & PESAVENTO MATTIOLI, S. (2009). Analisi archeometriche sulle anforettedi Canale Anfora. In: Scotti Maselli, S., Pesavento Mattioli, S. (ed.). I materiali dal Canale Anfora di Aquileia. Editreg,Trieste. In press.


Teaching assistant: 2 hours, “Petrografia applicata ai materiali ceramici”, Laurea di primo livello in Scienze e Tecnologie per iBeni Culturali (2008/2009).

Teaching assistant: 4 hours, “Georisorse per i Beni Culturali”, Laurea specialistica in Scienze e Tecnologie per i BeniArcheologici ed Artistici (2008/2009).


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In situ non destructive and medium destructive analysis on reinforced concrete elements from late 19th – first 20th centurybuildings located in the Veneto region, together with adequate sampling by means of core-hole drilling, local scarifications andsuperficial ablations. All analyses and sampling operations were performed in collaboration with the Structural andTransportation Engineering Department of the University of Padova.

Petrographic, mineralogical, microstructural and chemical analysis on the concrete samples taken during the field activities bymeans of polarizing microscope and SEM observations, EDS microanalysis and XRPD and AAS analysis. All analyses wereperformed at the Geosciences Department, University of Padova.

Analytical studies for the conservation state determination of the “Ex Tiro a Volo” complex entrance porch (Lido of Venice)and formulation of an adequate restoration project,. The work, committed by the municipality of Venice (Public BuildingsDepartment) and done in collaboration with the Structural and Transportation Engineering Department of the University ofPadova, was aimed at the execution of an urgent restoration of the structure.

Archaeometrical studies by means of petrographic, microstructural and mineralogical analysis on ancient mortars from threecastle remains of different ages (Cuol di Ciastiel Castle, Late Roman Empire, Pra di Got Castle, Early Middle Age, SachuidicCastle, XII-XIII Century), located in the High Tagliamento river Valley (Udine, Italy). All analyses were performed at theGeosciences Department, University of Padova.

XRPD analysis and compression tests on mortar samples used for the restoration of the Citadel of Acre, Israel. Analyses havewere performed at the Geosciences Department, University of Padova, and at the laboratory of the Structural andTransportation Engineering, University of Padova.

Participation to the “Progetto Paganica”, organized by the RELUIS consortium in collaboration with the National CivilProtection Department, in order to perform an urban survey of the city of Paganica, heavily damaged by the 2009 L’Aquilaearthquake. The field activities have been performed from the 27th to the 31st July 2009. During the survey activities a series ofmortar samples from various buildings of the town have been sampled and they will be studied from a petrographic andmineralogical point of view, in order to correlate state of damage of the buildings and nature and quality of the buildingmaterials.

Sampling of Roman Terra Sigillata potteries found in the city of Adria (Rovigo, Italy).

characterization studies on cement ...geo.geoscienze.unipd.it/sites/default/files/abstract...

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