Description
X-ray diffraction (XRD) is an analytical technique that can provide reliable solutions to many issues related to material science and industrial application, as quality control and process parameter optimization of manufacturing processes as geology, chemistry, pharmaceuticals, mechanics, semiconductors, nano-materials, additive manufacturing etc. However, it remains a technique with several aspects of complexity mainly related to data interpretation and instrument standardization that limits its application to procedures dependent on sample dimension and preparation. In addition to traditional powder diffraction techniques that are already used in civil engineering, X-ray diffraction has been used for years in mechanical engineering to determine residual stresses. In the past, some attempts of application in the field of civil engineering have been reported, but size of the available instrumentation at that time, have to date prevented a real use, despite the fact that its potentiality and applicability had been amply demonstrated. Over the last 4 year, in Italy, thanks to an intense ongoing investigation campaign, the measure of the tensional state of the post-tensioned cables of pre-stressed concrete structures has been the subject of evaluation campaign. The purpose of this dissertation is to provide general information on the physical principles of X-Ray-diffraction and to illustrate what are its current potentialities applied to the measurement of the tensional state of post tensioned cables (PTC) in the light of the instrumental innovations available to date.
