
Calculation of the Shear Modulus of Glasses 
A model for the shear modulus (modulus of rigidity), G, is now available (download calculator, 200 kB). It was developed by means of statistical analysis. Some interesting properties of the model are given here.
Number of data the model is based on = 627 (see source data references, 65 kB)
Degree of freedom = 603
R² = 0.9534
R²(adjusted) = 0.9516
R²(predicted) = 0.9490
Standard error = 1.0426
Mean of response (Shear Modulus in GPa) = 29.4283
Main glass composition validity limits of the shear modulus model in mol%: SiO2 4586%, Na2O 042%, CaO 027%, Al2O3 025%, MgO 027%, K2O 025%, B2O3 029%, BaO 026%, SrO 025%, Li2O 040%, PbO 050%, ZnO 018%, TiO2 025%, ZrO2 09%, Fe2O3 05%, F 09%, As2O3 00.6%, Sb2O3 00.5%, SO3 00.4%, (numerous additional model validity limits apply, considering glass component combinations).
The following spidergraph shows the influences of selected glass component additions on the shear modulus of a specific base glass, while keeping the weight ratios of all remaining components constant. The spidergraph will be different for other base glass compositions.
Influences of selected glass component additions on the shear modulus of a specific base glass (click image to enlarge)
For the shear modulus model development, 32 outliers had to be excluded. These are possibly caused by inaccurate data reported by the authors in the original literature or by copying the original data wrongly into the SciGlass 6.7 database. A list of the 32 possibly erroneous shear modulus data is provided here (23 kB).