In recent years, larger vibratory rollers have been implemented because of their improved efficiency. An unfortunate consequence of this is that greater ground motion caused by these larger vibratory rollers are now suspected of causing damage to adjacent infrastructure, particularly in or near urban areas. Various Federal, State, and foreign agencies have proposed vibration limit criteria, some intended to mitigate damage to structures, while others are based upon limiting human annoyance. Two of these existing criteria (U.S. Office of Surface Mines blasting level criteria, and German DIN 4150 Standard level for human annoyance) were selected to form the basis of a recommended practice for limiting vibratory compaction in critical work zones. These criteria are used to differentiate three zones on a plot of peak particle velocity versus vibratory roller frequency. A square root scaling law of ground motion is used to predict the ground motions from vibratory compaction equipment based on FWD data. With this predictor, a potentially vibration-sensitive portion of a resurfacing project can be identified using displacement-time histories from the FWD obtained during routine pre-construction testing. Detailed knowledge of the layering of the pavement structure or the geology of the surrounding site is not required. It is demonstrated herein that this predictor can successfully be used to restrict vibratory compaction near sensitive structures, including fragile buried infrastructure.
Samenvatting