Читать книгу Monument Future - Siegfried Siegesmund - Страница 200

Onsite investigations were done by comparable observations, damage mapping, electrical capacity and conductivity measurements on single building stones.

The electrical conductivity and capacity is basically dependent on the material and is also influenced by the moisture content of the material and the presence of ionic compounds. The used device (surveymaster/protimeter) measures moisture in buildings and other related structures both on (conductivity) and below (capacity) the surface.

Sampling of the drilling powder was also done. Field studies were done on a southwestern wall of the Zwartnotz ruins and the westen front facade of the Avan Cathedral.

This study concentrates on the historical mortars of the Zvartnots Cathedral (ZM), the Avan Cathedral (AM) and the restoration mortar (RM) from 1941 used for Avan (Fig. 4). From these three mortars an analysis of their aggregate/binder ratio and the grading curve of its aggregate were done in a mobile laboratory. Petrographical and fabric analyses of the building materials were performed on thin sections under a polarization microscope and cathodoluminescence (CL) microscopy. Hydrostatic weighing on the samples was carried out to acquire the particle and bulk density as well as the porosity (DIN 52102). Mercury intrusion porosimetry was used to acquire the pore radii distribution (Fig. 3d, h, l).