Most people have been in an office where the monitors shook every time someone walked through a corridor. In an office environment, this activity, while noticeable, is not generally detrimental to the regular course of activity. However, in certain types of buildings, such as research labs, surgery centers, or conference facilities, tiny vibration activity from foot fall and/or outside impacts can have horrendous consequences such as destroying years’ worth of research efforts, fouling precise measurements or disrupting surgical procedures.
Potential issues encountered due to lack of appropriate vibration analysis may include:
• Stairs that move noticeably when you walk on them.
• Sensitive equipment with inaccurate readings, such as microscopes, and MRIs.
• Disruption to animals in vivariums.
Accurate vibration analysis, generally the scope of a vibration specialist, has recently been added to a structural engineer’s tool box. Through the use of finite element and time history analysis style tools, structural engineers can now tackle the issue of human footfall caused vibrations. The analysis isn’t just for floors either. A quick to implement vibration analysis tool was developed several years ago by engineers that could be used on unusual or special framing such as stairs, cantilevers and bridges.
Your structural engineer can integrate the vibration analysis to their scope of work in the pre-design and schematic design phases of new buildings and “we can also evaluate and much more economically determine solutions to existing floors that do not meet 'overall/sweeping' vibration criteria standards,” says Principal, Ray Pugliesi.
This early consideration will help develop thorough understanding of potential design impacts for any vibration solution.
One of the biggest advantages to the finite element method versus Design Guide 11 (which is still the standard of practice for structural engineers) is that you can assess what's happening in one location due to walking in another location. Mahmoud Hachem, Senior Associate, developed the tool extensively when Degenkolb worked to install a first of its kind suspended MRI machine, in a California Hospital." says Sandy Hohener, Project Engineer
Additional thanks to contributors:
Mahmoud Hachem, Senior Associate, firstname.lastname@example.org;
Ariel Creagh, Design Engineer, email@example.com