Experimental Study on Modulus and Hardness of Ettringite

Abstract

The experimental study on the modulus and hardness (in‐press rigidity) of ettringite is carried out in this work. Firstly, the ettringite is obtained by chemical synthesis method. Secondly, samples are formed by filling the ettringite into resin matrix. Thirdly, the indentation modulus and hardness of ettringite are measured with different indentation depths by virtue of the instrument of MTS Nanoindenter XP. Finally, analysis on the modulus and hardness of the ettringite is performed according to the sample unloading curves. The results given by this work indicate that the magnitude of the modulus is 20.07 GPa and the hardness is 0.613 GPa.

Inference of the phase-to-mechanical property link via coupled X-ray spectrometry and indentation analysis: Application to cement-based materials

“…Such a prediction is in very good agreement with the estimation of plane-strain modulus of polycrystalline ettringite inferred from the experimental measurements of elastic modulus of packed powder compacts and its estimate at zero porosity [38]. On the other hand, the indentation properties of ettringite measured by direct experiment read H = 0.6 GPa and M = 20.3 GPa [39]. However, these results must be considered with caution as the measurements were executed on the agglomerations of needles with the characteristic cross-section in the range 0.1-1.0 μm, embedded in the epoxy resin.…”

A Critical Review of Existing Test-Methods for External Sulfate Attack

“…For example, the US methods more directly study the relationship between the strength of mortar exposed to ESA and its expansion. However, in some Chinese studies, sulfate attack was accelerated by electrical pulses and sulfate resistance was assessed based on the loss of strength [ 77 , 101 , 102 ]. The European approach requires continuous monitoring of the expansion and microstructural changes of samples exposed to a sulfate solution [ 17 , 76 , 93 , 105 , 106 ].…”

“…Many publications indicate that USBR 4908 has the ability to evaluate the effects of several characteristics of this material on the sulfate resistance of concrete, including the permeability, mineral and chemical admixture contents, and other mix design alternatives, as well as the effects of various curing procedures (see for example [ 6 , 8 , 16 , 27 , 41 , 45 , 46 , 66 , 69 , 71 , 73 , 75 , 76 , 77 , 78 ]).…”