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|a Installation of pile foundations by impact hammers produces numerous negative effects in the surrounding environment. For civil and geotechnical engineers, the most important one is the vibrations induced by various piles driving operations. Since many construction works including pile foundations installation usually take place in narrow urban areas, it is of great importance to predict and control the effects that may harm the surrounding structures. Hence, the study of all related aspects to the vibrations generation and propagation is insistently needed. This study has been conducted to investigate the influence of subsurface geology and groundwater conditions in controlling the effects induced by piles driving operations against nearby buildings. 2016 PLAXIS 3D software was used to numerically simulate the process of pilling and the effects reflected on one building located in the near proximity. Six models with similar soil, building, pile properties, soil strata order and with different groundwater and geological conditions have been constructed. In addition, dynamic load with dynamic load-time multiplier has been used to simulate a single acting hammer action on the pile head. Both, displacement and applied force changes have been investigated through one point located in the nearest building column to the pilling operation. After investigation, it has been found that the subsurface geology plays more significant role in controlling the effects of piles driving, compared to the groundwater conditions. However, the depth of pilling and the soil, pile and building properties have the major role. Lastly, by using the force resonance approach it was concluded that; driving piles through saturated soils causes lower values of force resonance compared with dry soils. In addition, driving piles through horizontal layers causes higher force resonance than that in inclined layers, but lower than that in folded (basin-shaped) layers.
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