Pie has extensive experience performing vibration monitoring during various construction and/or demolition activities. Construction activities, particularly heavy pier drilling, blasting, and pile driving, generate vibrations that can extend through the ground to buildings in close proximity to the construction site.
These vibrations range from barely noticeable to instances where building damage can occur. Vibration sensitivity of structures, and specifically those having historical significance, can vary greatly according to site specific soil type and construction type. Vibrations are measured in terms of peak particle velocity (PPV), which is recorded in inch per second [in/sec]. Vibration monitoring is intended to monitor the vibration levels with respect to specified thresholds at which damage could occur.
Pie has also monitored the implosion (i.e. demolition) of various structures. Both vibration and air overpressure are monitored during an implosion. The peak sound pressure level (PSPL) is recorded in decibels [dB(L)].
In conjunction with these services, Pie routinely provides pre-, in-progress, and post-construction site surveys and property condition assessments. Based on Pie’s experience, construction generated vibrations can typically be “felt” by nearby personnel prior to reaching thresholds where damage may occur. Pre-Condition Assessments are typically necessary to distinguish between any pre-existing distress and/or damage to any adjacent building(s). Proving distress and/or damage to be a pre-existing condition can be difficult without a combination of Pre-Condition Assessment (baseline), the results of vibration/implosion monitoring (accurate measurement of activities and impact on the subject property), and Post-Condition Assessment.
Pie has provided these services for contractors, developers, and owners of properties adjacent to construction.