Magnetorheological Fluid with Nano Fe_3O_4 for Performance Enhancement of MR Damper for Seismic Resistance of Steel Structures

摘要

Magnetorheological damper (MR damper) is one of the promising vibration control systems, applicable for damping seismic induced vibrations in structures, because of their ability to be controlled and to adapt their mechanical properties by varying the magnetic field, their high damping force, their low energy input required and their simple use. This paper presents the experimental results carried out to study the use of Nano Fe_3O_4 as component of MR fluid. The Nano Fe_3O_4 particles are obtained by an indigenous process to convert a waste product of chemical industry. The performance of Nano Fe_3O_4 MR fluid is compared with five commercially available samples in the market namely, Mill scale, cast iron (1), cast iron (2), carbonyl iron and white iron oxide. Surface morphology was identified using SEM & the average particle size was analysed using XRD. Viscosity & settling measurements were also performed for all the six samples. Shake table tests were conducted to study the performance of steel frame with MR damper. The model for the study was a single bay three storey steel frame where the response of the structure, in terms of acceleration, velocity and displacement was observed. It was observed that the percentage of reduction in displacement, velocity, acceleration, approximately 40 - 67% for structure with MR damper.