Detection of deteriorations in cultural structures created by carving into low-strength rocks by the non-destructive test (NDT) method

Abstract

In the cultural stone heritage, progressive deteriorations develop over time with the effect of atmospheric processes. These deteriorations can reach to a significant degree that threaten the integrity of the monuments built from weak-strength rocks. In this study, it is aimed to determine the deteriorations caused by atmospheric processes on the monument surface in cultural heritage works built by carving into low-strength pyroclastic rocks by non-destructive tests (NDTs). To this end, two historic structures in the Kilistra Ancient City of Konya (Turkey) were selected. The index, strength, mineralogical and petrographic properties of the rocks, in which the monuments were carved, were first investigated. Then, contour scaling, crack, efflorescence and biodeterioration types were determined on the facades of the monuments. Later, NDT deterioration change maps were prepared based on the data obtained by performing the relative humidity, Schmidt hammer rebound (SHR), and P-wave velocity (Vp) measurements on the facades of the monuments. In the deterioration maps, it was determined that the SHR and Vp values of the rock were low in the capillary, infiltration, and crack zones with water penetration in the monuments built on low-strength pyroclastic rocks. However, deterioration was less in the regions with more limited water access according to zones.

Key words： Pyroclastic; Kilistra ancient city; Deterioration; Non-destructive test; Weak-strength rock