The Influence of Fire and Water on Lime, Natural Hydraulic Lime, and Cement-Lime Mortars

Inspired by the devastating fire of the Notre Dame cathedral, this thesis examines lime, natural hydraulic lime, and cement-lime mortars after exposure to fire-level temperatures and subsequent quenching by water during suppression. The underlying hypothesis is that high temperatures from fire followed by quenching can affect the mechanical properties of mortars in ways that compromise their original structural performance and compatibility with architectural masonry. ASTM D3967-08 Standard Test Method for Splitting Tensile Strength of Intact Rock Core Specimens is carried out on three mortar types: dry hydrate lime-based mortar; natural hydraulic lime mortars; and Portland cement-lime mortars. Tensile strength testing is conducted on sample sets that are subjected solely to extreme heat, solely to saturation with water, to both heat and subsequent saturation, and control samples. In doing so, this thesis attempts to determine to what degree do these mortars retain their initial strengths, and, to provide information as to which formulations are best suited as repointing or bedding mortars for masonry exposed to fire.