HSEB Construction Vibration Monitoring

This page provides links to laboratory vibration monitoring data, so as to provide visibility and feedback for users near the HSEB project. Use the links below to see vibration data from individual stations.

Links are given for four different time periods, ranging from the most-recent 30 minutes of data to a broader view showing data gathered over the last three full days. All data are given as time histories, with a vibration level plotted against time. Additional explanatory text follows after the table:

Room most-recent data today's data most-recent day trailing 3 days
T-135 (m01) 30 minutes 4 hours 24 hours 72 hours
I-015 (m02) 30 minutes 4 hours 24 hours 72 hours
J-083B (m03-floor) 30 minutes 4 hours 24 hours 72 hours
J-083B (m03-tank) 30 minutes 4 hours 24 hours 72 hours
I-501 (m05) 30 minutes 4 hours 24 hours 72 hours
J-031 (m07) 30 minutes 4 hours 24 hours 72 hours
I-322 (m09-1) 30 minutes 4 hours 24 hours 72 hours
I-330 (m09-2) 30 minutes 4 hours 24 hours 72 hours
J-018B (m10) 30 minutes 4 hours 24 hours 72 hours
I-097 (m12) 30 minutes 4 hours 24 hours 72 hours
J-185 (m14) 30 minutes 4 hours 24 hours 72 hours

Additional discussion:

Each individual data point is the 30-second RMS level, in units of inches/sec (ips). Most instruments, processes, and animals exhibit greater sensitivity to sustained vibrations but can also be affected by short transients of sufficient magnitude. Both of these are reasonably captured by the 30-second RMS figure. Note that the pre-construction baseline data (collected in November 2019) were expressed in micro-inches per second; this is simply a difference in scale: 1000 uips = 0.001 ips.

Both the current and November datasets are expressed as an RMS figure and (with limited exception) are directly comparable. The November data were highly detailed and included spectra as well as time series. For simplicity, the monitoring data accessible through this page are being delivered as a time series alone. However, the system also saves frequency spectra when alerts are generated, so we can access these if needed. For a sense of the kind of data being delivered through the links above, see this annotated example PDF from the November dataset.

The plots in the links above provide hard numbers for vibration velocity. However, for these purposes, it is useful to view these data from a more-qualitative perspective. That is to say, this real-time monitoring effort is looking for unusual or extraordinary events that lie outside of normal experience. The data plots for individual rooms have been scaled according to historical data, so that typical daytime levels fall near the bottom of each plot. In other words, if the data look high on a plot, then vibration levels are indeed high when compared to historical data.

The system automatically generates and sends alerts to the project team when vibration levels exceed a notification threshold. These thresholds are customized for each room; they are based on the specific needs of different kinds of research and are informed by the historical data gathered in November.

Importantly, fluctuations and transients are part of the normal environment, so not all excursions are due to construction. Additionally, vibration levels are naturally higher during the daytime and lower overnight. Construction impact should be suspected when we see repeated large spikes or sustained high levels during active site hours (6AM–2:30PM, Monday–Friday). Data are being collected continuously, 24 hours a day and 7 days a week. Therefore, it is easy to see data gathered outside of construction hours for context.

The links above deliver recent data in a simple time-series representation for clarity; retrospective data for specific time periods may be obtained by contacting us by email and giving us your desired room numbers and dates/times. Most data are available starting 25 June 2020.

Other resources: