Petrographic Evaluation of Aggregate from Igneous Rocks: Alkali–Silica Reaction Potential

Abstract

A thorough petrographic evaluation of aggregates from igneous rocks in terms of their alkali–silica reaction (ASR) potential is crucial in ensuring the durability and long-term performance of concrete structures, especially those where access to additional alkalis is possible, such as from de-icing agents. The aim of the research was to assess the potential reactivity of aggregates from igneous rocks, as only such aggregates are used for concrete airport pavements in Poland. Petrographic analysis was conducted to identify the reactive minerals in the aggregate, and it was extended by quantitative image analysis. The strained, microcrystalline and cryptocrystalline quartz were found to be reactive components but significantly differed in content. It was found that aggregates from igneous rocks were characterized by different susceptibility to ASR and that methods to mitigate the occurrence of ASR should be considered to be used in airfield concrete. A relationship between the content of analyzed reactive minerals and the expansion of mortar bars in AMBT, as well as of the concrete prism in the CPT method, was revealed.

Feasibility study of replacing part of cement by igneous rock powder as cementitious material: based on mortar macroscopic properties and microstructure

“…Igneous rocks, also known as magmatic rocks, are one of the three main types of rocks that make up the Earth's lithosphere. According to statistics, igneous rocks account for 66% of the entire crust volume and are widely distributed (Antolik et al, 2023). Relevant studies (Piasta et al, 2016;Qaidi et al, 2022;Dobiszewska et al, 2023) have shown that some igneous rocks have certain pozzolanic activity after being processed to a certain fineness, and their active components SiO 2 and Al 2 O 3 can hydrate with cement clinker to produce calcium hydroxide and high-alkaline hydrated calcium silicate, and high-quality low-alkaline hydrated calcium silicate and hydrated calcium aluminate.…”