Sinkhole Investigation at Waterford Office Park
Protecting people and businesses from unseen dangers below the ground surface
Locating Sinkholes, Fast
Bigman Geophysical was contacted by a commercial property who was concerned about the possibility of a dangerous sinkhole in the parking lot outside of a building. There were signs of pavement slumping, and there was a suspicion that the aging rainwater drain system could have substantial leaks, and potentially present a situation where large amounts of soils were being washed away, with a risk of collapse. It was hoped that non-destructive testing could be used to find and asses any threats to the building and its staff, without shutting down the important office structure.
Bigman Geophysical determined that a ground-penetrating radar survey would most likely be able to find and digitally map voids and sinkholes across the property with minimal cost and without impacting the workplace. A survey was designed to quickly scan the area of concern, and the rest of the property, and then generate a computer model that could indicate any threats developing under the pavement.
Project Metrics
Expert analysis, outstanding results
The area of investigation was scanned using an RD1500 GPR system outfitted with a 250 MHz antenna and an RTK enabled GPS. The survey pattern was a modified bi-directional grid that followed the storm water system, drain pipes, and other features that could potentialy leak water.
During data collection the radar operator informed the commercial property that there were frequent indications of shallow washout under the parking lots, but these were too small to be dangerous. Near the main entrance, however, a larger unidentified feature was found. It was surrounded with road cones to protect the office staff.
The anomaly detected in front of the main doors to the office building presented a curiously rectangular component, indicating that it was purposely man-made. On the west side, however, this feature appeared swollen, and radar returns presented air-waves, indicating that the feature was hollow on that end, and not a uniform shape.
Bigman Geophysical submitted the results to the customer, and was informed that the location shown had been repaired in recent history, and that those repairs had apparently failed spectacularly. The resulting void space was large enough to be a threat to pedestrians and cars alike. The inspection across the property indicated numerous other minor problems that could be scheduled for non-emergency inspection and maintenance, and the customer was thrilled with the fast turnaround time and low cost.
Results Slideshow
