## 4 Discussion
### Effect of Ground-Borne Vibrations on the Building
Considering the variety of construction and material solutions used, varied ground conditions, depth of building foundations, etc., an extremely difficult task is to determine the acceptable vibration parameters that should be considered safe for various types of construction works. In some countries, however, an approximate assessment has been introduced for the impact of ground-borne vibrations on selected types of buildings, which are based on a comparative analysis of the actual vibration parameters registered on the building, with limit values being defined by relevant standards. They are based on the results of experimental research. An approximate assessment of the impact of ground-borne vibrations on buildings should be carried out in accordance with the provisions contained in national standards. If applicable regulations do not apply in a given country, norms of neighboring countries or international standards are usually used for this purpose. A few of the best such standards that are applicable in the case of predicting and assessing the impact of vibrations generated by the work of soil compaction equipment on buildings are German Standard DIN 4150-3 [23], British Standards BS 7385-2 [25], and BS 5228-4 [26], as well as Swiss Standard VSS-SN640-312a [27]. A somewhat different method of approximate assessment of the impact of vibrations on buildings is introduced by the Polish Standard [28]. The first three standards are based on the registration of the time histories of three mutually perpendicular components (x, y, z) of vibration velocities at the base of the building on the side of the building facing the source of vibration [25], and if not possible--on the foundation wall or supporting wall of the building (usually at, or slightly above the level of adjacent terrain from the side of source of vibrations) [23], or on the ground, outside of the building--in the case of a predicted impact assessment of vibrations on the building (or in the case of an existing building, when for some reasons it cannot be implemented at the base of the building) [25]. The DIN [23] standard additionally recommends recording the time histories of velocity of horizontal vibrations (x, y) on the top floor of the building. The assessment itself is based on the comparison of the PPV (Peak Particle Velocity) independently for each of the three components of the unweighted velocity signals (expressed in peak component particle velocity PPVx, PPVy, PPVz) [23]. In the case of the Polish Standard PN-B-02170:2016-12 [28], an approximate method based on the so-called \"dynamic impact scales\" (in Polish \"_Skala Wphyvow Dynamicznych_\"--SWD) developed for two types of the most common buildings has been introduced. According to the SWD scales, the time history of the accelerations or velocities of horizontal vibrations (x, y) on the foundation or supporting wall of the building from the side of the source of vibrations, and at the level of the adjacent terrain, are subject to recording. The assessment of the impact of ground-borne vibrations on the building consists of analyzing fragments of recorded signals (with amplitudes \(\geq\) 0.2 PPA--separately for components x and y) in 1/3-octave bands, and applying the determined values of accelerations or vibration velocities on nomograms with marked damaging zones. The SWD scales introduce five such zones [28]. The standard VSS-SN640-312a [27] is applicable to both transient and continuous vibrations. The standard introduces the division of buildings into four classes (I-IV; class II--includes buildings with foundation walls and floors in concrete, and walls in concrete or masonry, and two types of vibration sources: machines, traffic, and blasting. Threshold values, above which building damage may occur, are set independently for the following frequency bands: 10-30 Hz and 30-60 Hz--in machines and traffic generated vibrations, 10-60 Hz and 60-90 Hz--in blasting.