Abstract: The use of portable and high-energy x-ray system can provide a very promising approach for the inspection of aged concrete structures. However, due to the effect of large scattering of low-energy x-ray in a thick concrete, the noise properties and contrast of the radiographic images need to be optimized to ensure reliable interpretation. Therefore, in order to improve the inspection ability, an image denoising method with the combination of wavelet and curvelet transform and image contrast e...
英字タイトル:
Image Enhancement for Concrete Bridge Inspection with Portable 950 keV/ 3.95 MeV X-ray Source

Abstract: Since more and more bridges built several decades ago in Japan have become aged and dangerous, the non-destructive evaluation of those bridges is really an urgent problem. CT system with portable 3.95MeV linacs for bridge inspection is considered to work on-site, considering the law of Japanese radiation protection allows using linacs up to 4MeV outside radiation controlled area. The system would confirm the internal steel si tuation of bridges and analyze structural strain and stress with 3D mod...
英字タイトル:
On-Site Bridge Inspection with Partial CT by 3.95Mev X-Band Linac Source

In situ CT application for NDE of degradation bridges is under development, with portable 950keV/3.95 MeV X-band linac as x-ray source. Collimator is adopted to reduce scattered X-ray noise. Material analysis and erosion estimation through dl-energy CT method is integrated in order to inspect the erosion situation of i nner steel rod. Reconstruction technique with incomplete projection data is studd considering limitation of projection angle range during onsite scanning. Furt hermore, based on 3D model bui...
英字タイトル:
Partial Inspection and Dual-energy CT Material Analysis with 950keV/3.95MeV X-Band Linac

Our portable X-band (9.3GHz) 950KeV linac has been successfully upgraded. The problems of RF power oscillation , beam current oscillation and reduction and finally lack of X-ray intensity were solved by replacing the axia l coupling cavities with the side-coupled ones. Designed X-ray dose rate of 0.05 Sv/min@lm is going to be achi eved. Length of the accelerating tube is reduced to less than 25 cm. X-ray source part with the local radiation shielding is connected by the flexible waveguide with the box of t...
英字タイトル:
Study on Portable X-band 950keV linac X-ray Sourcefor On-site Nondestructive Inspection

可搬型高エネルギーX線源を使用した橋梁内部の複数アングルからの撮像を、「トモシンセシス」と 呼ばれる技術を用いて再構成することで、内部構造の3次元視覚化が可能となる。これにより、橋梁健全性評価システムの高精度化が期待できる。2017 年 6 月と 7 月に実施した実橋梁検査の結果も考察する。 ...
英字タイトル:
3D Visualization of Inner Bridge using Portable High Energy X-ray Source and its Valuation