Abstract: Material on a remote side of a partition separating first and second domains is evaluated by disposing at least one ultrasonic transmitter and a plurality of spaced ultrasonic receivers along a first side of the partition in the first domain. The transmitter is activated to form ultrasonic waveforms that comprise propagated quasi leaky-Lamb waves constituting extensional waves having symmetrical zero-order modes within the partition. The received ultrasonic waveforms are processed to determine the envelope of the waves propagating through the partition from a first receiver to a second receiver that is located more remote from the transmitter than the first receiver and whose separation from the first receiver is known. The integral envelope attenuation per distance of the wave propagating through the second domain over a predefined interval establishes that the second domain contains a solid when higher than a predetermined threshold.

Abstract: Material on a remote side of a partition separating first and second domains is evaluated by disposing at least one ultrasonic transmitter and a plurality of spaced ultrasonic receivers along a first side of the partition in the first domain. The transmitter is activated to form ultrasonic waveforms that comprise propagated quasi leaky-Lamb waves constituting extensional waves having symmetrical zero-order modes within the partition. The received ultrasonic waveforms are processed to determine the envelope of the waves propagating through the partition from a first receiver to a second receiver that is located more remote from the transmitter than the first receiver and whose separation from the first receiver is known. The integral envelope attenuation per distance of the wave propagating through the second domain over a predefined interval establishes that the second domain contains a solid when higher than a predetermined threshold.