Advanced remote structural and geotechnical assessment of sheet pile walls using drone-mounted laser doppler vibrometry and high-resolution aerial imaging coupled with COMSOL multiphysics modelling

For investigating sheet pile walls and embankments, techniques such as cone penetration testing and ground penetrating radars are relatively expensive, carbon intensive, time consuming and of limited depth range. A new technology for surveying sheet piles and retained ground was proposed, which uses Laser Doppler Vibrometers, and drone mounted electro-magnetic excitation devices. The interpreted damping characteristics allows detection of inadequately compacted areas and reveals the embedment depth and defects in the sheet piles, including misalignment, buckling, and bending out of plane.

With vibrometry, excavation or site clearance may not be required and the technology is (a) contactless and measures vibrations in micro-meter precision, (b) allows rapid muti-point excitation and vibration measurements on sheet pile tops, (c) suitable for even hidden measuring positions or for measuring through water and other transparent media, (d) applicable for long working distances, high temperatures, high voltage, cold, wet, dry or dusty and misty conditions.