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Wpływ wybranych kwarcowych dodatków mineralnych modyfikujących beton warstwy wierzchniej na jego zespolenie z podkładem betonowym

Sadowski Ł., Hoła J.

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2017

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nr 1(19)

21--26

PL

W pracy dokonano na drodze badawczej oceny wpływu wybranych kwarcowych dodatków mineralnych modyfikujących beton warstwy wierzchniej na jego zespolenie z podkładem betonowym. Dodatkami tymi były mączka kwarcowa oraz skaleniowo-kwarcowa stosowane w różnej ilości w stosunku do masy cementu. Badania zespolenia warstw wykonane metodą pull-off wykazały, że mączka skaleniowo- kwarcowa wpływa zdecydowanie niekorzystnie na to zespolenie.

EN

Based on performed research in this paper the evaluation of the effect of selected quartz mineral admixtures applied in added concrete on their adhesion to concrete substrate was presented. These admixtures were quartz and feldspar-quartz mineral used in varying amounts relative to the weight of cement. Research performed by pull-off method presents that feldspar-quartz mineral powder definitely affects adversely on that adhesion.

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The effect of air entraining admixtures and cement types on the properties of fresh mortar

Piasta W., Marczewska J.

Structure and Environment

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2013

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Vol. 5, no. 1

11--17

EN

In order to explain the effect of air entraining admixture (AEA) and the type of cement on the properties of fresh mortar, the following tests were carried: bulk density, flaw and air content of 20 air entrained mortars and 20 nan air entrained mortars made of ordinary Portland cement (OPC) and blended Portland cements: blast furnace slag (BSF) - limestone powder (LP), fly ash - limestone, fly ash (FA) and (BFS) cement. It has been found that the modern anionic AEAs from the group of alkyl sulfates are much more efficient and active than traditional ones i.e. sodium abietate. It is difficult to entrain air into mortars with cement of various types to the same content of air. This requires to carry out a number of tests to determine the appropriate amounts of AEA. The air entrainment of LP cement mortar does not significantly change its flow. The air entrainment of BSF and FA cement mortars increases their workability. The lowest content of air was stated in non-air-entrained mortars with FA cement, the highest air content was observed in BFS cement mortars. According to the results the bulk density of mortars is inversely proportional to the amount of air entrained.

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Wykorzystanie metod inżynierii materiałowej w analizie ceramiki starożytnej - badania makro- i mikroskopowe

Konopka K., Biernacka A., Riegert D., Kobylińksa U.

Inżynieria Materiałowa

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2010

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Vol. 31, nr 1

71-75

EN

The aim of this paper was to characterize the structure of fragments of ceramic vessels found in the Early Iron Age strongholds from 7th and 5th century B.C. at Starosiedle in Poland and at Biehla in Germany. This research was done in collaboration between material scientists from the Technical University of Warsaw and archaeologists from the Institute of Archaeology and Ethnology of the Polish Academy of Science (PAN). The main idea of our work is to adapt the methodology employed to characterize structure and properties commonly used in materials science and engineering to ancient pottery. In this paper preliminary results and examples of the application of fractography to the study of ancient pottery are presented. Selected ceramic fragments were examined by light and scanning electron microscopy. The fractographic examinations of vessel fractures permitted the identification of the shape, color, and admixture distribution in the sam- ples. It also enabled us to observe the structure of the ceramic matrix and in particular cracks and delaminations (Fig. 1÷3). Observations combined with the point analysis of the chemical composition performed with the help of a scanning electron microscope supplemented the examinations of the kind and structure of the admixtures (Fig. 4÷6). In conclusion, our investigations have demonstrated that the application of materials engineering techniques to the study of prehistoric pottery is beneficial for both archaeology and materials and engineering science as both sides can profit from the different point of view offered by the other. For the archaeologists, the results of materials science techniques for the examination of ancient pottery will permit establishing the relations between ceramic structure and the manufacturing techniques. On this basis, conclusions can be reached about the development of pottery technology in the context of the contemporary social and cultural background. For the materials and engineering scientists this collaboration allows them to study materials which have been affected by their deposition context for thousands of years, and thus offers them the chance to predict the effects of long-term storage in particular context for modern materials.