Experimental verification of the developed soil model describing the propagation of vibration wave in the ground

The problem of propagation of vibration waves in soil caused by passing trains and vehicles is an important issue for the assessment of their influence on environmental impacts and engineering structures such as bridges, viaducts, historic architecture and residential buildings. The issue is complex because the nature of the soil is heterogeneous and the groundwater level changing depending on the season and this creates great difficulties in developing a theoretical model of vibration wave propagation. The paper presents developed numerical model of soil consisting of 4.3 million cubic finite elements based on the geological properties of soil. Developed model based on Drucker- Prager material model, which is often used in numerical methods for simulating the behaviour of different soil types. In addition, the material properties of the soil was specially prepared and allowed to use them directly in the material model used. Both concrete (building) and steel (plate forcing) were modelled using an isotropic material model. Element size was set at 300 mm. This value was determined by the adopted frequency range studied (0 to 100 Hz) and due to verification by simulation results of experimental studies in which excitation has been implemented in the frequency of 33 Hz (base frequency of excitation signal) and 66 Hz (second harmonic of excitation signal). The cut-off frequency 100 Hz defines a minimum wavelength propagated in the soil (based on the stiffness and density of the soil) and 10 finite elements was adopted at a wavelength, which is 3 meters to the ground, for the correct mapping of a sinusoidal waveform. Subsequently, experimental studies were performed to verify the model from which the conclusions are presented in the work. The work was carried out in a research project 4875/B/TO2/2010/38 financed by Ministry of Science and Higher Education.