■On June 10th-12th, senior research engineer Mr. Takuyuki Tamura and research engineer Mr. Shohei Momoki had presentations at 12th International Conference "Structural Faults and Repair-2008".

On June 10th-12th, 12th International Conference "Structural Faults and Repair-2008" was held in Edinburgh, Scotland, UK. Sessions took place at "The Assembly Rooms", a historical building built in 1787. More than 150 participants were gathered. From Tobishima Corporation Research Institute of Technology, senior research engineer Mr. Takuyuki Tamura and research engineer Mr. Shohei Momoki had presented their paper with the following titles: ・MONITORING OF TUNNEL DEFORMATION BY MEANS OF TDM BASED FBG OPTICAL FIBRE MEASUREMENT SYSTEM T. Tamura, K. Kumagai, H. Motoyama, T. Shiotani and R. Knapp ■ ABSTRACT Recently Fiber Bragg Grating (FBG) based optical fiber sensing systems have been applied widely for many civil structures. Contrary to the Wavelength Division Multiplexing (WDM), in FBG adapting Time Division Multiplexing (TDM), multiple points of more than 100 points on a single line can be monitored, that is suitable for long-term health monitoring of large civil structures. In the present paper, this TDM based FBG sensing system was installed at a deformed tunnel in a cold region. A total of 100 strain and deformation on the surface of lining concrete was measured with the optical interrogator at about 1 km away from the sensors. So far even under such a severe monitoring condition, continuous data acquisition with good accuracy has been successfully conducted. ・COMBINED STRESS WAVE TECHNIQUES FOR MONITORING OF FRACTURE IN CONCRETE SLABS S. Momoki, D. G. Aggelis, A. Hirama and T. Shiotani ■ ABSTRACT In the present paper the mechanical and acoustic emission behavior of concrete slabs tested in four point bending is discussed. The specimens consisted of two layers of plain and vinyl fiber concrete with metal rebars. The aim was to assess the effect of fibers on the strength, as well as the cohesion obtained between the layers by different binding conditions. At different loading steps, ultrasound pulse velocity was measured and a three dimensional tomographic reconstruction of the internal condition of the specimen was obtained. Although cracking decreases the accuracy of source location, the results for any loading stage show good agreement between the acoustic emission event location, the ultrasound structure and the visual observation of the actual cracks.

The conference is considered one of the top world events in civil engineering due to active attendance by numerous professors, engineers and publishers, and its high level of scientific announcements. The main themes of the conference concerned extending the life of bridges by inspection, management, analysis and strengthening and inspection and repair issues for concrete (composite) as well as masonry buildings and civil structures.

Mr. Momoki has been presented with "CNS FARNELL NDT AWARD" in recognition of their paper. This is one of the most prestigious awards in the Non-Destructive Technique category, sponsored by CNS Farnell ltd., a world-leading company famous for its highly efficient NDT equipment.

Keynote Lecture		Mr. Takuyuki Tamura
Mr. Shohei Momoki		Awards Ceremony (Mr. Momoki and Prof. Shiotani)

Takuyuki Tamura & Shouhei Momoki Tobishima Corporation