The impact of the size of reactive aggregate on the mechanical properties of concrete and the extent of ASR damage over the time

Document Type : Original Article

Authors

1 Ph.D. Student, Department of Civil Engineering, Bu-Ali Sina University, Hamedan, Iran

2 Associate Professor, Department of Civil Engineering, Bu-Ali Sina University, Hamedan, Iran

3 Assistance Professor, Department of Civil Engineering, Bu-Ali Sina University, Hamedan, Iran

10.22065/jsce.2023.408846.3183

Abstract

Alkali-Silica Reaction (ASR) is identified as one of the reasons for destruction of the concrete structures and poses a threat to its durability. ASR causes the cement paste to expand, crack, and consequently weakens the strength of the concrete. The simplest solution to prevent ASR is to test aggregates' reactivity potential, identify the reactive ones, and then exclude them from the concrete mix. This research aims to examine the impact of fine and coarse reactive aggregate on (1) the mechanical properties of damaged concrete including compressive strength, tensile strength, and modulus of rupture, and (2) the extent of expansion that occurred over time due to the occurrence of this phenomenon. To this aim, four concrete mixtures are made using different combinations of fine and coarse aggregates, that could be reactive or nonreactive, with a water-cement ratio of 0.5. According to the results, the concrete mix whose reactive part was only sand or only gravel expanded 4.4 or 3.5 times over the control mix design (a concrete mixture that is only made of non-reactive aggregates), respectively. Furthermore, using fine reactive aggregates in the concrete mixture reduces compressive strength, tensile strength, and modulus of rupture compared to using coarse reactive aggregates. Therefore, replacing reactive sand with non-reactive sand is recommended as a more effective solution to control the ASR, compared to replacing reactive gravel with non-reactive gravel.

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Articles in Press, Accepted Manuscript
Available Online from 24 September 2023
  • Receive Date: 27 July 2023
  • Revise Date: 16 September 2023
  • Accept Date: 24 September 2023