Physical and mechanical properties of the repaired sandstone ashlars in the facing masonry of the Charles Bridge in Prague (Czech Republic) and an analytical study for the causes of its rapid decay
2011
Abstract
The decay of the newer stone has been accelerated by use of Portland cement paste as the binding and fill materials, instead of the original lime-based and cociopesto-type mortars.The hardened Portland cement paste makes an almost impermeable barrier, with permeability three to four orders of magnitude lower, compared to the original mortars and natural stone.