## 3 Results  
### Experimental Measurements  
Field studies were conducted in two distinct locations. The first site, situated amidst the bustling streets of a city, was housed in a distinctive three-story building with Klein slabs, which had a brick ceiling on steel beams and boasted a unique architectural layout, with both an attic and a basement supplementing the main floors. The city's vibrant atmosphere, characterized by a constant flow of traffic along the busy street flanked by two lanes in each direction, provided a dynamic backdrop for the research activities conducted within the premises. In contrast, the second location offered a more tranquil setting, nestled within a quaint small town in the same region. Here, the research took place within a one-story structure with a wooden slab, designed in a traditional single-family fashion, complete with its own attic and basement spaces. Through these selected sites, the field studies were able to capture the effects of traffic-induced vibration, allowing undisturbed data collection and analysis. Measurements were precisely conducted utilizing a specialized measuring disk that had been intricately linked to the sensor apparatus, as illustrated in Figure 2. The designed apparatus, in accordance with the detailed methodology stipulated in the standardized literature [13], had been strategically positioned on the floor of the highest level, precisely within the region most susceptible to external vibrations. Throughout the experimentation process, precise measurements of acceleration were consistently obtained along three distinct axes, X, Y, and Z, in a total of ten rigorous tests for each of the scenarios under investigation. These tests were conducted in the presence of various vehicular movements, with the initial scenario encompassing the passing of cars, delivery vehicles, buses, and trucks. Subsequently, the raw data collected underwent accurate filtering procedures, adhering to the strict criteria outlined in the standards [13]. The outcomes derived from this analysis were obtained for every individual measurement at the required frequency, ensuring a comprehensive understanding of the vibrational patterns observed. Furthermore, through thorough data analysis, extreme values were determined and cross-referenced with a human vibration threshold chart for comparison and visualization purposes, facilitating a comprehensive assessment of the potential impacts of the observed vibrations. Two field tests were carried out during the day, in the morning, under real conditions. Normally, about 40 vehicles per hour pass near the two structures investigated. Most of them are passenger cars, and heavy trucks are observed quite rarely (not more often than about every 20 min). According to the Polish standard for recording vibrations from passing vehicles that affect a building and the persons inside it, it is important to record whether the vibrations are short-term or long-term. As the sum of vibrations exceeds 30 min a day, the second standard case was considered. The first study was carried out in a tenement house (see Figure 3a) located 12 m from a main road. It is a masonry 4-story building. The slabs are made of steel beams (Klein floor); this is a slab from the beginning of the 20 th century, currently found in old buildings. The general condition of the road surface is considered to be good; there are sewage manholes, sewage grates, and holes covered with asphalt in the examined section. The indicated road is used by different vehicles, such as passenger cars, delivery vans, trucks, buses, and construction vehicles. During the measurements, passenger cars, delivery cars, and trucks were recorded. The second measurement was carried out on a single-family two-story building with a wooden slab (see Figure 3b). The building is located 7 m from the local asphalt road. The general condition of the road surface is good; there is a speed bump right next to the building across the entire width of the road. The road traffic includes trucks, delivery vans, and passenger cars.