POTENTIAL OF ALKALI SILICA REACTION IN CONCRETE USING KASHMIR AGGREGATE

Abstract

The mountainous belt of Kashmir, bearing complex geological formations, provides aggregates the have potential to be used in construction industry for both small as well as large scale projects. However, a very expansive reaction, known as Alkali-Silica Reaction (ASR) must be carefully evaluated to ensure their suitability and to minimize durability problems in concrete structures. The present study aims to analyze the potential of Alkali silica reactivity in aggregate samples collected from three different quarries of Kashmir region. These aggregates were examined through chemical analysis, petrographic analysis and standard test procedures, including ASTM C 227 and ASTM C1260. Based on the standard expansion limits for mortar bars, all the aggregates sources were identified as potentially reactive. Mortar cubes were also analyzed at different ages to determine the mechanical properties under different ASR conditions. The results reveal that reduction observed in the concrete properties varied among different aggregate sources, depending on their chemical and mechanical properties of aggregates. It was observed that the reduction in strength was found to be inversely proportional to the expansion observed in the mortar bars.