Tomographic reconstruction for concrete using attenuation of ultrasound

The development of attenuation tomography for concrete is discussed. Fundamental ultrasonic measurements of cubic specimens and numerical simulations of wave motion were conducted to examine the decay in amplitude of ultrasound when impinged by defect, and compare its sensitivity to the delay in travel time. An algorithm was then developed to facilitate simultaneous tracing and distribution of amplitude factor in a three-dimensional model by iterative computation. The algorithm was used for reconstruction of attenuation tomographic for visualizing concrete interior. Experimental results indicated successful identification for the location of a defect that was embedded in concrete, thus implying the potential of attenuation tomography as a complementary method to the travel time tomography to enhance soundness evaluation of concrete.