Vibrations caused by heavy construction at museums are potentially harmful to museum buildings and artwork. Protection of these objects calls for a reliable method of vibration control during construction projects. In this presentation, background information will be provided on vibrations and their effects on humans, buildings, and artwork. Then, conservative limits for protection of buildings and artwork from damage from vibrations during construction will be recommended. Research and examples will be cited that show: 1) most works of art in good condition have damage thresholds that are much higher than the limits recommended for construction vibrations; 2) vibrations to which art objects are exposed during transit are often much higher than the limits recommended for construction vibrations, without damage; 3) similar limits have been used during several previous museum construction projects, without damage; 4) humans can perceive much lower levels of vibration than the recommended limits, so it should be anticipated that vibrations at these levels will be noticeable to building occupants even though they are not damaging; and 5) even ambient (day-to-day background) vibrations in museums can approach the recommended limits, which reinforces the conservative nature of the limits.
The research and the authors’ experience show that the greatest risks for damage to art objects during construction projects are from walking of unrestrained light objects on smooth surfaces; resonance of objects that have natural frequencies similar to steady-state construction vibrations like sheet pile driving; and vibratory motion of extremely fragile objects or those with serious pre-existing weaknesses. Measures should be taken to protect against these unique risks.
Vibration control during museum construction projects has often been based on judgment and qualitative analysis. This presentation will outline a scientific methodology, based on available research and state-of-the-art technology, to protect the museum while not unduly constraining, encumbering or slowing the construction process. The key steps include preconstruction testing, selection of appropriate vibration criteria, planning for preconstruction collections movement, development of a project-specific vibration control specification, field trials and condition surveys, construction-phase vibration monitoring along predetermined safe lines, and stringent protocols should near-limit or over-limit events occur. The methodology has proven successful in recent construction projects at leading U.S. museums and is offered for the benefit of other museums undertaking similar work.
Two examples of large-scale implementation of the methodology will be described: the first involving three major construction projects at The Art Institute of Chicago from 2005 to 2009, and the second being the expansion of the Saint Louis Art Museum from 2009 to date. Both projects involved extensive preconstruction testing, vibration control development, and construction-phase vibration monitoring systems.
