Mechanical Properties of Alkali-Silica Reaction Gel Measured by Nanoindenter
The mechanical properties, particularly the elastic modulus and hardness of alkali-silica reaction (ASR) gel are measured at the microscopic scale by nanoindentation. The ASR gels are simulated in the laboratory by reacting amorphous silica (i.e., borosilicate glass) with different alkali hydroxide solutions. The measured elastic modulus of gel, formed by reacting borosilicate glass in sodium hydroxide solution was found to have a mean value of 2.96 GPa, while the gel formed from a combination of sodium hydroxide, potassium hydroxide, and calcium hydroxide solution has the mean modulus of 5.17 GPa. The results show that the presence of potassium and calcium alkalis increases the elastic modulus and hardness of the gel. A student’s t-test performed on the results confirmed the statistical significance.
Alkali-Silica Reaction, Mechanical Property, Nanoindentation
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