Groundborne Vibration Assessments
The California Environmental Quality Act (CEQA) requires Groundborne Vibration Assessments to determine effects on buildings and other structures. Groundborne vibrations from natural phenomena (e.g., earthquakes, volcanic eruptions, sea waves, landslides) or manmade causes (explosions, machinery, traffic, trains, construction equipment) can cause human annoyance and structural damage.
ECORP provides groundborne vibration assessments to help government agencies, builders, developers, construction contractors, and other project proponents meet CEQA regulations and move rapidly towards construction. These assessments are performed as part of our noise analysis, modeling, and monitoring services.
How Does ECORP Measure Groundborne Vibrations?
There are many ways to measure groundborne vibrations, but one of the most common is peak particle velocity (PPV). Groundborne vibrations below 0.1 PPV are typically unnoticeable by the average person.
However, at 0.2 PPV, these vibrations can cause architectural damage and annoyance to those who may feel the walls shaking.
ECORP assesses groundborne vibrations by first isolating the construction site and the type of equipment to be used. The total PPV of different pieces of construction equipment is calculated using data provided by Caltrans and the U.S. Department of Transportation.
In addition to assessing construction equipment groundborne vibrations at their source, these legal regulations also include mathematical equations for assessing PPVs at different distances from the cause of the vibrations.
Using these figures and equations, ECORP produces two-dimensional groundborne vibration models which specify whether or not PPVs will exceed the 0.2 threshold within residential or commercial zones.
Mitigating Groundborne Vibrations
If groundborne vibrations are projected to exceed a maximum threshold, ECORP designs mitigation strategies to reduce vibration levels. After designing these strategies, we perform new groundborne vibration assessments. These generate new models which can show whether groundborne vibrations will be successfully mitigated below the legal threshold.
Many groundborne vibration mitigation strategies are easy to implement, such as:
- Replacing equipment with other equipment that causes less significant groundborne vibrations
- Using certain construction equipment only during scheduled times
- Restricting the use of high-vibrational equipment at night
- Setting up a public complaint phone number for nearby residents and businesses to call if groundborne vibrations begin causing noticeable shaking within a home or commercial building
- Specifying which pieces of equipment can and cannot be used concurrently with others
Comparative Modeling
Many times, excessive groundborne vibrations are a consequence of excessive noise levels. Similarly, strategies designed to mitigate noise levels that exceed legal thresholds are often successful at reducing groundborne noise levels.
As part of our three-dimensional noise modeling services, ECORP noise and groundborne vibration experts create comparative models of mitigated and unmitigated noise and groundborne vibration levels at a given project site.
Contact ECORP for Noise Analysis and Groundborne Vibration Assessments
Over the last 16 years, we’ve learned how to quickly and effectively measure and mitigate groundborne vibrations for clients across California, Arizona, and New Mexico.
Our groundborne vibration assessments are performed as part of our noise analysis and monitoring services. By modeling noise and vibrations together, we capture a more holistic picture of how construction will impact nearby human and wildlife populations.
To learn more about our noise analysis and groundborne vibration assessments, contact ECORP today and schedule a consultation.