Modeling the Phenomenon of Propagation of Technological Impulses in Subsoil

This article presents a model describing the phenomenon of vibration propagation in the subsoil. Stroke-based technologies are extremely effective in geotechnical practice; however, accompanying vibrations are harmful to the neighborhood. Impulses from impacts and vibrations resulting from ground improvement (dynamic compaction or dynamic replacement), installation of piles, sheet piles, and so on, are numerically analyzed. The article focuses on the damping mechanism and description of the significant variability of the deformation characteristics for small strains. In numerical analyses, an advanced multimechanism constitutive hardening soil model is used. The Rayleigh model is used to describe the phenomenon of damping of the soil massif. The finite-element method is used to solve a defined initial–boundary–value problem. The results of the analyses form the runs of displacement after the impulse. On this basis, the acceleration amplitude can be determined and the range of impact on the environment is estimated. For the analyzed drop of a heavy hammer, good compliance of the acceleration amplitudes obtained from simulations with results from field tests is achieved, both in qualitative and in quantitative terms. The presented model can be used to analyze the predictability of the harmful effects of shocks during design work.

The results presented in the field of numerical modeling of vibration propagation in the soil medium may be of great practical importance. In situ experimental verification of the results obtained from the calculations allowed us to state that the proposed model is realistic and gives reliable results. It must be remembered that shock and vibration technologies are extremely effective in geotechnics. At the design stage, the performance of appropriate numerical analyses may allow for a proper assessment of which technologies of work are applicable in a specific case. This will allow for a significant reduction in the implementation of experimental plots, which impacts the time and price of construction works. On the other hand, in the realization stage, performed numerical analyses will be an excellent supplement to the monitoring results.