From: On-site monitoring for better selection of stone repairs: a case study
 | Ostermundigen Blue sandstone | Repair mortar |
---|---|---|
Porosimetry (mercury intrusion porosimetry) | ||
 Average pore radius (µm) | 7.9 | 34.6 |
 Total porosity (%) | 17.2 | 35.1 |
Hygric swelling at 95% RH ɛ 95 (mm m−1) | 0.43 | 0.49 |
Hydric swelling ɛ s (mm m−1) | 1.25 | 5.02 |
Thermal expansion α (10−6 K−1) | 12.9 | 32.7 |
Poisson’s ratio ν (−) | 0.2a | 0.4b |
Elastic modulus E (GPa) | ||
 Wet | 0.43 | – |
 Dry | 1.87 | 2.03 |
Relaxation modulus | ||
 Dry | – | \( E_{0} { \exp }\left( { - ( t/\tau)^{\beta } } \right)^{\text{c}}\) |
Tensile strength (MPa) | ||
 Wet | 0.3 | – |
 Dry | 1.0 | 2.7 |