Surfactant-Synthesized Consolidants Applied To A Granitic Medieval Necropolis In NW Spain. Laboratory And In Situ Effectiveness Evaluation

Abstract

ABSTRACTIn this work, the consolidation of a granitic medieval necropolis in NW Spain severely affected by a granular disintegration is presented. The causes of this degradation were first diagnosed and, given the need to consolidate the altered surfaces, the effectiveness of two newly synthesized nanoconsolidants (UCAD-2o and UCAT-do) were evaluated and compared with a conventional TEOS under laboratory conditions. Changes in pore size distribution, vapor diffusivity, color changes and abrasion resistance (slake durability test) were evaluated. One of the nanoconsolidants was identified in laboratory as the most suitable for application in situ and it effectiveness and harmful effects, once applied on the tombs, was evaluated by the peeling test and the modifications in the color. The research contributes new data on nanoconsolidant effectiveness on granites and also reaffirms the need to perform the effectiveness evaluation prior to in situ treatment, applying criteria related to the intrinsic properties of the rock and to the active deterioration mechanisms.