System, Method, and Apparatus for Determining Soil Density

摘要: A system for measuring soil density includes a plurality of signal emitters paired with receivers situated within the and below grade (e.g. from 10 to 30 feet grade). The periodically emit (e.g., ultrasonic signal), some which is reflected back by soil. If compact close emitter/receiver, received after short delay has high strength. less or there gap between greater and/or lower By making several measurements strength, baseline established. Later, periodic strength are made. measured differs baseline, likely changed.