Following up on our Vibration Group's recent analysis, we're excited to share the vibration response of a residential mass timber project. Referring to our previous post, https://lnkd.in/egj5swhm, the results below show the cross-laminated timber (CLT) floor subjected to walking at 90 steps per minute. Omer Tigli Ph.D, P.E., INCE explains the outcome in his post below! #creativetothecore #structuralengineering #structuraldesign #structuralengineer #structuralengineers #masstimber #clt #cltfloors #vibration #vibrationanalysis #vibrationresponse #vibrationconsulting #vibrationservices
Here's the #vibration response of a #CLT floor subjected to walking at 90 steps per minute. Various recommendations exist for acceptable vibration levels in #masstimber floors with regard to #humancomfort. Some recommendations are expressed in #acceleration units, while others use #velocity units. In this analysis, we processed the data to display the floor's performance in both metrics. The top right figure shows the acceleration data in its raw form and as a weighted root-mean-square (RMS) in percent of g (gravitational acceleration). The lower right figure presents the data in velocity units (micro-inches per second, or mips) as 1/3 octave band spectra. For context, U.S. Mass Timber Floor Vibration Guide published by WoodWorks recommends the following performance targets for residences and offices: Peak acceleration of 0.5 %g (equivalent to 0.35 %g RMS), or RMS velocity in the range of 16,000 mips to 32,000 mips. The peaks in the octave band spectra indicate a dominant floor #resonance (bay mode) at approximately 12Hz and a secondary resonance (panel mode) around 26Hz, both excited by walking. We have measured these #modeshapes and will share an animation of the experimental mode shapes in a future post. For details on the construction of the #CLT floor, please refer to our first post (see comments).
