## 4 Discussion
### Effect of Ground-Borne Vibrations on the Building
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline
**Stage No. (Distance)/Technical** & \multicolumn{4}{c}{**I (Ls = 15 m)**} & \multicolumn{4}{c}{**II (Ls = 10 m)**} & \multicolumn{4}{c}{**III (Ls = 5 m)**} \\ \cline{2-11}
**Condition of Build.** & \multicolumn{2}{c}{**Good**} & \multicolumn{2}{c}{**Bad**} & \multicolumn{2}{c}{**Good**} & \multicolumn{2}{c}{**Bad**} & \multicolumn{2}{c}{**Good**} & \multicolumn{2}{c}{**Bad**} \\ \hline
**Device/Mode/Depth of Comp.** & **1x** & **2y** & **1x** & **2y** & **1x** & **2y** & **1x** & **2y** & **1x** & **2y** & **1x** & **2y** \\ \hline MTS V8/X1/0.4 m & I & I & II & I & II & I & II & I & II & I & III & I \\ MTS V8/X1/1.2 m & I & I & II & I & I & II & I & II & I & III & I \\ MTS V8/X1/1.8–2.0 m & II & I & II & I & I & II & I & II & I & II & II \\ \hline MTS V8/X2/0.4 m & I & I & II & I & II & I & II & I & II & I & II \\ MTS V8/X2/1.2 m & I & I & II & I & I & I & II & I & II & I & II \\ MTS V8/X2/1.9-2.0 m & I & I & I & I & I & I & II & I & I & II & I \\ \hline MTS V8/X3/0.4 m & I & I & I & I & I & I & I & I & II & I & I \\ MTS V8/X3/1.2 m & I & I & I & I & I & I & II & I & I & I & I \\ MTS V8/X3/1.9–2.0 m & I & I & I & I & I & I & I & I & I & I & I \\ \hline Plate compactor/0.4 m & I & I & I & I & I & I & I & I & I & I & I \\ Plate compactor/1.2 m & I & I & I & I & I & I & I & I & I & I & I \\ Plate compactor/1.8–2.0 m & I & I & I & I & I & I & I & I & I & I & I \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Impact of vibrations on a residential building according to the dynamic impact scale SWD-II (in Polish _”Skala Whywho Dynamicznych II”_) [28]. of the device in the range of the analyzed distance parameters of the source of vibrations from the building (0-15 m), and the depth at which works related to the compaction of soil were conducted (from 0 m to 1.8-2.0 m). If we assume that a building is in good technical condition (as it was in the analyzed case), then the maximum second damaging zone can be expected (marked as \"II\" in Table 9)--i.e., with vibrations that are harmless to the building structure, which may, however, cause accelerated building wear, first scratches in rendering and plaster, and scratches in wall corners and facades, etc. (so-called cosmetic damages). If, however, with the building being the subject of the assessment was in poor technical condition or set on a low rigidity subsoil, vibrations would have to be classified even within the third damaging zone (see in Table 9--designation \"III\")--that is, vibrations that are harmful to the building, which may cause local cracks and scratches that weaken the structure of the building and that reduce its load-bearing capacity and resistance to further dynamic influences (there may also be falling off of rendering and plasters, scratches on the joints of structural elements, etc.). This type of harmfulness was found only in the case of the shortest distance from the building (Ls = 5 m), in which the hydraulic compactor operated in X1 mode and the poor technical condition of the building or low soil stiffness occurred. In X2 mode, the MTS V8 compactor generates slightly less intense vibrations, which are classified into the II damaging zone at a distance of 15 m of hydraulic compactor from the building, only in the case of the poor technical condition of the building, and the compaction of the ground at lower depths (0.4 m and 1.2 m). As can be seen from the assessments summarized in Table 9, the least often to exceed the lower limit of the necessity of taking into account the dynamic impact on the building occurs in X3 mode--when the compactor works at distances smaller than 10 m, and when we consider that the building is in poor technical condition, or is placed on a ground with low stiffness or a non-continuous foundation.