Application of Special Granular Structures for semi-active damping of lateral beam vibrations

• An innovative method of semi-active vibrations’ damping is presented.
• Free vibrations of a beam, encapsulated in a granular sleeve are investigated.
• Dynamic properties of the structure can be controlled by the underpressure value.
• The dynamic model of a damped granular beam is provided.
• Application of a granular structure provides effective in damping of vibrations.

A new semi-active damping of vibrations method is presented, which is based on loose granular grains that are placed in a hermetic sleeve that is surrounding a steel beam, forming a complex controllable granular beam structure. Changing the partial pressure inside the structure results in changes of the elastic and dissipative properties of the system resulting from the granules’ jamming mechanism. The paper presents both experimental and theoretical analyses of a vibrating cantilever granular beam system. The linear Bernoulli–Euler beam model with Kelvin–Voigt damping that depends on underpressure is used to describe the behavior of the investigated structure. The proposed strategy of vibrations damping is found to be easy to implement, provides satisfactory damping, and is efficient, but also indicates that a nonlinear beam model may be a better fit.