Mitigating footfall-induced vibration in long-span floors

Long-span lightweight floor systems with low damping are susceptible to serviceability problems due to human excitations. This paper discusses two remedial measures to alleviate disturbing footfall-induced vibrations observed on a real office floor of steel-concrete composite construction. One treatment involves stiffening the existing floor beams while the other utilises passive control with an innovative distributed multiple viscoelastic tuned mass damper (TMD) system. Several finite element models reflecting different remedial scenarios are analysed from which the TMD approach and the traditional stiffening technique are found to be comparably effective in reducing the vibration level. However, the proposed TMD solution is far superior, feasible and non-intrusive when applied to existing floors. A probability-based evaluation of the effectiveness of the TMD system is also conducted, taking into account likely variations in the walking force and dynamic properties of both the floor and dampers. The custom-made damper system has been successfully installed on the real floor and performed efficiently in various field tests.

[1]  F. Collete.  Tuned Mass Dampers for a suspended structure of footbridges and meeting boxes , 2002 .

[2]  Paul Reynolds,et al.  Vibration Testing and Active Control of an Office Floor , 2008 .

[3]  Jeong-Hoi Koo,et al.  Semiactive Tuned Mass Damper for Floor Vibration Control , 2007 .

[4]  Daniel A. Cuoco,et al.  Taming Structural Vibrations , 1990 .

[5]  Hugo Bachmann.  VIBRATION UPGRADING OF GYMNASIA, DANCE HALLS AND FOOTBRIDGES , 1992 .

[6]  Christoph Heinemeyer,et al.  Design Guide for Floor Vibrations , 2008 .

[7]  Mehdi Setareh,et al.  TUNED MASS DAMPERS FOR BALCONY VIBRATION CONTROL , 1992 .

[8]  Emmanuel E. Velivasakis.  LaGuardia High School Gymnasium, Tuned Mass Dampers ` Dance to the Tune to Tame Floor Vibrations , 1997 .

[9]  Emad Gad,et al.  Evaluation of footfall induced vibration in building floor , 2011 .

[10]  Hugo Bachmann.  Case Studies of Structures with Man-Induced Vibrations , 1992 .

[11]  Linda M. Hanagan,et al.  Active Control Approach for Reducing Floor Vibrations , 1997 .

[12]  H. Yamaguchi,et al.  Fundamental characteristics of Multiple Tuned Mass Dampers for suppressing harmonically forced oscillations , 1993 .

[13]  Emad Gad,et al.  Improving a current method for predicting walking-induced floor vibration , 2012 .

[14]  Thomas M. Murray,et al.  Using Tuned Mass Dampers to Eliminate Annoying Floor Vibrations , 1995 .

[15]  Christiane Butz,et al.  Generalisation of criteria for floor vibrations for industrial, office, residential and public building and gymnastic halls : final report , 2006 .

[16]  Kenneth H. Lenzen.  Vibration of Steel Joist-Concrete Slab Floors , 2007 .

[17]  Mary Galea,et al.  Basic gait and symmetry measures for primary school-aged children and young adults. II: walking at slow, free and fast speed. , 2011, Gait & posture.

[18]  Anthony C. Webster,et al.  Application of Tuned Mass Dampers To Control Vibrations of Composite Floor Systems , 2003 .