Experimental and Analytical Research on Resonance Phenomena of Vibrating Head with MRE Regulating Element

Abstract

A vibratory pile hammer (VPH) is a mechanical device used to drive steel piles as well as tube piles into soil to provide foundation support for buildings or other structures. In order to increase the stability and the efficiency of the VPH work in the over-resonance frequency, a new VPH construction was developed at the Military University of Technology. The new VPH contains a system of counter-rotating eccentric weights, powered by hydraulic motors, and designed in such a way that horizontal vibrations cancel out, while vertical vibrations are transmitted into the pile. This system is suspended in the static parts by the adaptive variable stiffness pillows based on a smart material, magnetorheological elastomer (MRE), whose rheological and mechanical properties can be reversibly and rapidly controlled by an external magnetic field. The work presented in the paper is a part of the modified VPH construction design process. It concerns the experimental research on the vibrations during the piling process and the analytical analyses of the gained signal. The results will be applied in the VPH control system.

Compressive properties of magnetorheological elastomer with different magnetic fields and types of filler

“…Other researchers investigated the dynamic properties of MRE as functions of the application conditions, such as the strain amplitude, rubber/magnetic particle interactions, and magnetic field . Miedzińska et al studied the experimental and analytical studies on resonance in MREs . Kukla et al studied the mechanical properties in MREs .…”

“…14,16,17 Miedzińska et al studied the experimental and analytical studies on resonance in MREs. 18 Kukla et al studied the mechanical properties in MREs. 19 Kim and Gorodkin et al studied the rheological and magnetic properties of MR fluids reinforced with carbonyl iron particles with different particle size.…”