High-energy X-ray diffraction is a powerful tool providing access to structure in disorder materials. In the present study, a set of twelve Al2O3 center dot SiO2 center dot CaO center dot Na2O glasses with different Na2O contents and SiO2/Al2O3 ratios have been measured at the ID11 Material Science beamline (ESRF, Grenoble) at 78 keV. Empirical potential structure refinement, radial distribution function and first sharp diffraction peak analyses have been applied to extract a comprehensive picture of their atomic networks. The resulting structural findings have been correlated with the important technological property of the glass transition temperature, obtained from differential scanning calorimetry measurements.