Sheet-piles are used on a lot of construction sites and a standard technique of inserting them in the soil is the so-called "vibratory pile driving". This paper describes how measurements of vertical accelerations have been used to calculate the operating displacement shapes of the studied sheet pile by means of finite element (FE) simulations and how the parameters of the vibratory pile driving (force generated by the vibrator and by the soil) have been calculated. The used equipment is shortly described as well as the experimental set-up: to get a stationary situation, the sheet piles are driven during the tests on woodblocks and conveyor belts, which are buried in the soil at a depth of 1 m so that they cannot dive into the soil. The characteristics (amplitude, frequency and phase) of the acceleration-signals are obtained by appropriate filtering and assuming a stationary state. These characteristics are used within FE simulation to determine (least-square method) the forces applied at both the ends: by the vibrator and by the counter bearing system, i.e. the woodblocks and the conveyor belts in the soil. The following conclusions are obtained: the system of woodblocks and conveyor belts can not be modelled as a spring-damper system; the force amplitude generated by the vibrator can be calculated in an acceptable way; variations of the parameters in the harmonic simulations show the importance of the exact position of the clamping system for the generation of bending and coupled torsion-bending waves; this process is robust against the variations of the damping.
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