Tensile Cracks
One of the causes responsible for the damage of buildings is the horizontal tensile strain. The program highlights individual parts of a building with a color pattern that corresponds to a given class of damage. The maximum value of the tensile strain is provided in the text output.
The program offers predefined zones of damage for masonry buildings. These values can be modified in the frame "Stage settings". Considerable experience with a number of tunnels excavated below build-up areas allowed for elaborating the relationship between the shape of subsidence trough and damage of buildings to such precision that based on this it is now possible to estimate an extent of compensations for possible damage caused by excavation with accuracy acceptable for both preparation of contractual documents and for contractors preparing proposals for excavation of tunnels.
Recommended values for masonry buildings from one to six floors are given in the following table.
Horizontal strains (per mille)
Proportional h.s. (per mille) | Damage | Description |
0.2 - 0.5 | Microcracks | Microcracks |
0.5 - 0.75 | Little damage - superficial | Cracks in plaster |
0.75 - 1.0 | Little damage | Small cracks in walls |
1.0 - 1.8 | Medium damage, functional | Cracks in walls, problems with windows and doors |
1.8 - | Large damage | Wide open cracks in bearing walls and beams |