Loading...
Publication
A Review on Alkali-Silica Reaction Evolution in Recycled Aggregate Concrete
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| Alkali-silica reaction (ASR) is one of the major degradation causes of concrete. This highly deleterious reaction has aroused the attention of researchers, in order to develop methodologies for its prevention and mitigation, but despite the efforts made, there is still no efficient cure to control its expansive consequences. The incorporation of recycled aggregates in concrete raises several ASR issues, mainly due to the difficult control of the source concrete reactivity level and the lack of knowledge on ASR's evolution in new recycled aggregate concrete. This paper reviews several research works on ASR in concrete with recycled aggregates, and the main findings are presented in order to contribute to the knowledge and discussion of ASR in recycled aggregate concrete. It has been observed that age, exposure conditions, crushing and the heterogeneity source can influence the alkalis and reactive silica contents in the recycled aggregates. The use of low contents of highly reactive recycled aggregates as a replacement for natural aggregates can be done without an increase in expansion of concrete. ASR expansion tests and ASR mitigation measures need to be further researched to incorporate a higher content of recycled aggregates. | 2.13 MB | Adobe PDF |
Advisor(s)
Abstract(s)
Alkali-silica reaction (ASR) is one of the major degradation causes of concrete. This highly deleterious reaction has aroused the attention of researchers, in order to develop methodologies for its prevention and mitigation, but despite the efforts made, there is still no efficient cure to control its expansive consequences. The incorporation of recycled aggregates in concrete raises several ASR issues, mainly due to the difficult control of the source concrete reactivity level and the lack of knowledge on ASR's evolution in new recycled aggregate concrete. This paper reviews several research works on ASR in concrete with recycled aggregates, and the main findings are presented in order to contribute to the knowledge and discussion of ASR in recycled aggregate concrete. It has been observed that age, exposure conditions, crushing and the heterogeneity source can influence the alkalis and reactive silica contents in the recycled aggregates. The use of low contents of highly reactive recycled aggregates as a replacement for natural aggregates can be done without an increase in expansion of concrete. ASR expansion tests and ASR mitigation measures need to be further researched to incorporate a higher content of recycled aggregates.
Description
The authors gratefully acknowledge the support of CERIS, from IST-University of Lisbon, the Foundation for Science and Technology, and also National Laboratory for Civil Engineering-LNEC for their support through the project RE-IMPROVE (Expansive reactions in concrete-Prevention andmitigation of their effects).
Keywords
alkali-silica reaction recycled aggregate concrete degradation test-methods characterization
Pedagogical Context
Citation
Barreto Santos, M., De Brito, J., & Santos Silva, A. (2020). A Review on Alkali-Silica Reaction Evolution in Recycled Aggregate Concrete. Materials, 13(11), 2625. https://doi.org/10.3390/ma13112625.
Publisher
MDPI