Investigation of alkali-silica reactivity potential of aggregate sources in the eastern part of Thailand

Abstract

This paper reports the study of ASR expansion potential of different aggregate
types which were randomly collected from some sources in the eastern coast of
Thailand (three different lithology based-rocks are metamorphic, igneous, and
sedimentary rocks). The samples were tested using several methods namely;
Petrographic Analysis, Accelerated Mortarbar Test (AMBT), Accelerated
Concrete Microbar Test (ACMT), Uranyl Acetate Gel Fluorescence Test and
Microscopic Characteristics Analysis using digital stereo microscope. The
aggregates in this study were Calc-silicate, Granite, Limestone and Greywacke.
The results showed that aggregates of the same type but from different sources
were similar in mineralogical compositions and chemical compositions. The
AMBT expansion results indicated the larger expansion of samples in sedimentary
group than the suggested values of the standard which indicated the potential ASR
deleterious expansion. The uranyl acetate test of micro bars sample indicated the
evidence of ASR gel at aggregates’ rims as well as inside aggregate particles. These
findings supported the expansion results. Also, the studies of thin section revealed
the evidence of ASR gel at the aggregates’s rim, inside the aggregates and in the
matrix.