Solutions for a complex world:
Monitoring Ground Vibration with Geophysical Tools
Article by: Hannah Peterson | hydroGEOPHYSICS
Ground vibrations associated with construction or blasting can cause damage to nearby structures, disturb surrounding residents, and disrupt sensitive processes. Often, the damage caused by vibrations will not be apparent at the time of activity. Thus, it is critical to monitor ground vibrations during construction and blasting projects as damage can go unnoticed and deteriorate over time.
The primary purpose of seismic vibration monitoring is to address potential damage to nearby buildings.
Seismic ground vibration monitoring measures PPV (Peak Particle Velocities) and accelerations to understand if nearby activity vibrations are significant enough to cause concern. Geophysicists and engineers assess ground vibrations to ensure activities do not cross-tolerance thresholds that may be problematic. Monitoring equipment is installed on the surface and measures the velocities in real-time. The equipment has a minimal footprint and can be carried by hand to the installation site, making it easily deployable where vehicle access may not be possible. Real-time data can be provided as necessary to decide whether to stop or adjust construction activities if vibration levels surpass established limits.
Ground vibrations produced by blasting or construction are often unable to be felt by humans; however, the damage they can have is significant. Cracking and weakening of structures adjacent to the disturbance may occur at certain velocity thresholds. In addition to the damage to the physical structures, vibrations can alter the state of underlying soil or sediments, eventually leading to structural integrity issues.
The setup for a monitoring system includes a seismograph and a geophone that continually monitor velocities in three directions at the point of installation. The geophone is installed on a ground surface or predetermined structure. The waveform data collected with the instrument includes frequencies and characteristics of the waves, providing vital information on the vibration source’s magnitude and location. Project-specific thresholds are set so that an event is recorded when the PPVs surpass the tolerance levels, and a detailed report of these events can be generated. Multiple geophones are often installed to pinpoint where the largest vibrations are occurring and assess the waves’ attenuation.
Example of a seismograph vibration monitoring system. The image shows a seismograph data logger, geophone, and microphone used for ground vibration monitoring.
For your next project, prevent costly damage and liability from ground vibrations with HGI’s expertise in seismic vibration monitoring. Implementing a vibration monitoring program at your new or existing project site has the following benefits:
- Quantify vibrations associated with construction, demolition, or blasting
- Easy installation and minimal footprint
- Can be installed in environmentally sensitive areas
- Reliable, meaningful data that can address risk in real-time
HGI will provide unique solutions for your vibration monitoring project, from survey design to acquisition, and reporting. We can also offer geophysical tools for other construction challenges.
About the Author: Hannah Peterson | hydroGEOPHYSICS
Hannah Peterson is a Staff Engineer and geophysicist for hydroGEOPHYSICS with a background in engineering, coding, and data analysis. She has broad field experience involving geophysical data processing, surveying, and geological interpretation in both land and marine settings. Her professional focus is on electromagnetics, electrical methods, data processing, and inversion.
Hannah holds a BS in Geophysical Engineering from the Colorado School of Mines and an MS in Earth Science from the University of California San Diego.
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