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Influence of sodium and potassium formate on the ASR reactivity of granite aggregate

Antolik Aneta

Structure and Environment

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2022

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Vol. 14, no. 3

69--75

EN

Use of de-icing agents is necessary in winter to maintain appropriate quality of road and airport surfaces. Formate or acetate de-icing agents are safer for aircraft and the environment than the commonly used sodium chloride, but may cause an alkali-silica reaction in concrete. The study investigated the influence of sodium formate and potassium formate on the occurrence of ASR (alkali-silica reaction) in mortars with granite aggregate. Accelerated mortar-bar tests at 80°C using various de-icing agents were performed and detailed studies of the SEM-EDS microstructure were carried out.

PL

Stosowanie środków odladzających jest niezbędne do zimowego utrzymania odpowiedniej jakości betonowych nawierzchni drogowych i lotniskowych. Środki odladzające na bazie mrówczanów lub octanów są bezpieczniejsze zarówno dla środowiska, jak i statków powietrznych niż powszechnie stosowany chlorek sodu, jednak mogą wywoływać reakcję alkaliczno-krzemionkową kruszywa w betonie. W pracy analizowano wpływ mrówczanu sodu i mrówczanu potasu na potencjał wystąpienia ASR (alkali-silica reaction) w zaprawach z kruszywem granitowym. Przeprowadzono badania ekspansji w 80°C z zastosowaniem różnych środków odladzających oraz przeprowadzono szczegółowe badania mikrostruktury SEM-EDS.

2

Ocena kruszyw granitowych stosowanych do betonu pod względem wystąpienia potencjalnej reaktywności alkalicznej

Jasiński Wiktor, Duszyński Andrzej, Jórdeczka Łukasz, Pryga-Szulc Aneta

Przegląd Geologiczny

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2020

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Vol. 68, nr 10

759--763

EN

The study deals with granite aggregates of various fractions, originating from Polish and foreign deposits, used for concrete in communication engineering. The article discusses the issue of cement reaction with granite aggregate during exposure under specific climatic conditions and how it affects the durability of concrete structures. Granite aggregates were used to prepare concrete beams that were subjected to research analysis according to PN-EN and ASTM. Particular attention was paid to processes occurring between reactive minerals (including chalcedony, opal, tridimite, and highly-strained quartz) and the alkalis present in cement. Research methods and results of alkaline reactivity tests on granite aggregate trabecula are presented. They were carried out at the Concre¬te and Aggregate Division of the Road and Bridge Research Institute - Wroclaw Branch. The paper also presents the analysis of research results and criteria to which potentially reactive aggregates are subject.

3

Experimental and numerical investigation of the alkali-silica reaction in the cement-based materials

Grymin W., Gawin D., Koniorczyk M., Pesavento F.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 4

1698--1714

EN

The main subject of this paper is the investigation of the influence of the alkali-silica reaction on the microstructure and the transport properties of the cement-based materials. In the experimental research, mortar bars prepared with two different aggregates and stored in conditions of various alkali content were examined. Influence of the reaction on the microstructure of the material was investigated using mercury intrusion porosimetry, water capillary suction test and water vapour adsorption test. Mathematical model of the alkali diffusion and the reaction development is presented. It allows to take into consideration the influence of alkali concentration and aggregate sizes on the reaction development. The numerical code was developed using the finite element, finite difference and Newton-Raphson methods. Good accordance of the results obtained using the proposed model with the experimental data available in literature was obtained.