Search results for "nondestructive"
showing 6 items of 86 documents
Adapting robot paths for automated NDT of complex structures using ultrasonic alignment
2019
Automated inspection systems using industrial robots have been available for several years. The IntACom robot inspection system was developed at TWI Wales and utilizes phased array ultrasonic probes to inspect complex geometries, in particular aerospace composite components. To increase inspection speed and accuracy, off-line path planning is employed to define a series of robotic movements following the surface of a component. To minimize influences of refraction at the component interface and effects of anisotropy, the ultrasonic probe must be kept perpendicular to the surface throughout the inspection. Deviations between the actual component and computer model used for path-planning resu…
Toward the Development of Load Transfer Efficiency Evaluation of Rigid Pavements by a Rolling Wheel Deflectometer
2020
The jointed rigid pavement is currently evaluated by the Falling weight deflectometer which is rather slow for the testing of the jointed pavements. Continuous nondestructive evaluation of rigid pavements with a rolling wheel deflectometer can be used to measure the load transfer and is investigated. Load transfer is an important indicator of the rigid pavement&rsquo
Inspection of architectural structures with integrated electrical methodologies and infrared thermography
2005
B030 INSPECTION OF ARCHITECTURAL STRUCTURES WITH INTEGRATED ELECTRICAL METHODOLOGIES AND INFRARED THERMOGRAPHY Abstract 1 The attention of this paper was focused on the detection of moisture and local inhomogeneities inside architectural structures with electrical methodologies and infrared thermography. To this end a suitable specimen was fabricated using a mixture of sand water and concrete and with slag inclusions. To monitor the moisture variation with time in concrete nondestructive evaluation with both the techniques was made three months after the specimen fabrication and repeated again six months later. Introduction The inspection of architectural structures generally includes vario…
Decay assessment of stone-built cultural heritage: The case study of the cosenza cathedral façade (south calabria, italy)
2021
This study aims to assess the different decay phenomena affecting the Cosenza Cathedral façade (Calabria, South Italy) through the evaluation of the relative damage indices. For this goal, a multidisciplinary approach was applied exploiting both nondestructive and microdestructive techniques. Such a combination enabled proposing an intervention priority scale that can be helpful to institutions when planning a prompt restoration intervention. The results suggest the efficiency of this approach to obtain a multidisciplinary diagnostic and conservation system for the management and valorization of the Cultural Heritage also in terms of monitoring, maintenance, and selection of the most suitab…
Phase-delayed laser diode array allows ultrasonic guided wave mode selection and tuning
2013
Selecting and tuning modes are useful in ultrasonic guided wave non-destructive testing (NDT) since certain modes at various center frequencies are sensitive to specific types of defects. Ideally one should be able to select both the mode and the center frequency of the launched waves. We demonstrated that an affordable laser diode array can selectively launch either the S0 or A0 ultrasonic wave mode at a chosen center frequency into a polymer plate. A fiber-coupled diode array (4 elements) illuminated a 2 mm thick acrylic plate. A predetermined time delay matching the selected mode and frequency was employed between the output of the elements. The generated ultrasound was detected by a 215…
On the use of the EMI for the health monitoring of bonded elements
2014
The low weight, robustness and fatigue resistance of adhesive joints make them suitable for structural joints. A fully developed nondestructive evaluation technique however is needed to monitor and assess the quality of bonded joints. In the present paper the application of the electromechanical impedance (EMI) technique is proposed. In the EMI method a piezoelectric transducer (PZT) is attached to the structure of interest. The high sensitivity and low power consumption make the EMI method feasible for real time structural health monitoring. In this study we investigated the sensitivity of the electromechanical response of a PZT to the curing and the quality of the adhesive used for bonded…