EFFECT OF SOIL PROPERTIES ON PEAK PARTICLE VELOCITY (PPV) DUE TO PILE-DRIVING USING FINITE ELEMENT ANALYSIS

Pile-driving is a common method of foundation construction where the soil is not strong enough to support the load of the structure through conventional shallow footing. This method is widely used in residential and industrial building, bridges, highways and etc. Along with the benets of using this method, pile driving is also a source of negative environmental eects. Noise and air pollution are the most commonly expressed concerns, but, ground vibrations originating from the pile driving impact also have important adverse eects. They can cause disturbances to adjacent structures and also disrupt the operation of nearby sensitive equipment and facilities. Permanent settlement, densication and liquefaction may also occur in the soil due to such vibrations. A common factor for evaluating the amount of vibrations is peak particle velocity (PPV), which is maximum velocity that soil particles reach during the pile driving process. PPV is the maximum velocity that a soil particle experiences during the driving of a pile from the ground surface to the desired depth. Ground motion due to pile driving generally depends on (1) the source parameters (method of driving, energy released, and pile depth), (2) the interaction between the driving machine, the pile and the soil, and (3) the propagation of waves through the soil. In this article, a two-dimensional nite element model is validated using a case study of pile-driving data conducted in the Chennai site in India. Then, by modeling a pile in sandy soil with dierent soil relative densities, Poisson ratio, moduli of elasticity, Unit weight, friction angle and damping ratio, the eects of these parameters on vibrations of the ground surface, and peak particle velocity on the surface, were studied. The results showed that the increase in friction angle and Poisson ratio in- creases the PPV. However, increase in the modulus of elasticity, damping ratio and soil unit weight, decreases the PPV. Also, scrutiny of PPV occurrence time shows that by variation of the in uencing parameters, except the modulus of elasticity, this time is almost constant.