## 3 Experimental Validation of the Models  
The proposed models were validated using in situ measurements performed in the Upper Silesian Coalfield (USC) region [29; 30]. The USC area is one of the mining regions in Poland with the most intensive mining tremors. Figure 6: Placement of springs modeling the soil in the transverse, longitudinal, and vertical directions. The actual building used to validate the models was a two-story masonry building, which is used for office purposes. This building, which does not have a basement, is founded on concrete strips, and the building subsoil consists of medium and fine sand with yellow dust inclusions. According to the geological documentation, dynamic soil parameter Cz = 50 MPa corresponds to such site (ground) conditions. The load-bearing masonry walls form a transverse-longitudinal system. The building is 12.7 m \(\times\) 29.9 m in plan and a height of 7.3 m. Figure 7 shows a photo of this building and horizontal directions parallel to the transverse (x) and longitudinal (y) axis of the building. For a detailed description of the structure and subsoil layers, please refer to articles [29; 30]. Since this article focuses on the transmission of mining vibrations from the free-field to the foundation of the building, therefore simultaneously registered courses of horizontal components x and y of free-field and building foundation vibrations were taken into account at the model verification stage. Additionally, based on the recorded courses of vibration components, the dominant vibration frequencies were calculated using the FFT (Fourier spectra). From hundreds of mining shocks registered during the full-scale tests [29; 30], two representative and different mining tremors were considered for validating models. Those mining tremors (rock bursts) were marked as No. 1 and No. 2. The analyzed vibration components x, y (accelerations denoted as _a_) and corresponding FFT results are shown in Figure 8 (direction x) and Figure 9 (direction y). Figures 8 and 9 confirm that records of vibration accelerations induced by mining tremors measured at the same time on the free field near the building and on the building foundation level can differ significantly [6; 7; 29; 30]. For instance, in the cases of both representative mining shocks, the maximum acceleration values (\(a_{\text{max}}\)) of the horizontal components x and y of vibrations at the level of the building foundations were several tens of percent smaller than on the free field. For mining tremor No. 1, for the horizontal components x of vibrations, the results of the FFT analysis indicated the dominant frequencies of the recorded courses on the ground in the range of 10.5-14 Hz and from the higher band from 15.5 to 18 Hz. These frequencies were attenuated by the building acting as a low-pass filter. The lower frequencies, from the range of 4 to 8 Hz, are practically transmitted from the ground to the building foundation without changes. This is particularly well visible in the case of mining tremor No. 2--comp. Figure 8b. For the component x of vibrations for mining tremor No. 2, the FFT results show a wide band of dominant frequencies. The frequency characteristic of this component was different compared to mining tremor No. 1. The low-frequency band in the course of building foundation vibrations overlapped  
Figure 7: A photo of the actual building with marked horizontal transverse (x) and longitudinal (y) axis. with the dominant vibration band for the x component. This band was in the range of 3.2 to about 8.2 Hz. Higher vibration frequencies in the range from 8.2 to 16 Hz were attenuated by the building--comp. Figure 8b. In the case of the component y of vibrations, the frequency characteristic differed from that of the horizontal component x. For mining tremor No. 1, the dominant frequencies up to 10 Hz were transmitted almost without changes. Ground vibration frequencies from 10 to 15 Hz were significantly attenuated by the building. In the case of mining tremor No.