Integrated Geotechnical-Acoustic Marine Soil Measurement Device

In this research, a miniature computer based chirp sonar will be developed for making rapid surveys of offshore sediments. The sonar reflection data will be integrated to both differential GPS navigation and spot geotechnical measurements in a manner that will provide rapid large scale assessment of marine soil properties. The cumulative survey results will be presented, in real time, in the form of computer generated contour maps detailing dediment property variations in density, prosity, and shear strength. A large portion of the sonar system development will be extracted from our Navy sponsored research 6(biography). Minimal new research is needed for the actual sonar hardware component of this development effort. The new research that is needed and proposed will focus on developing the interface between the acoustic measurements and geotechnical measurements taken from such devices as penetrometers, instumented cones, vibratory corers, and other devices. At selected site locations, the data from these measurements will be entered as ground truth into the system computer model. The ground truth data is used in the computer program to calibrate the models that relate acoustic impedance to sediment properties 6. This research will result in the design of a commercial low cost combined acoustic/geotechnical instrument that will perform rapid material resource assessment, pollution monitoring, and provide data for marine construction design.