Amendment on the Kenchiku-shi Law (Architect/Engineer Law), the Building Standard Law and other relating Law as measures after the case of structural data fabrications was passed at the No.164 and No165 session of the National Diet. This report is an outline of the Kenchiku-shi Law Amendment of those amendments.

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Several kinds of laws concerning Asbestos containing materials were revised in 2006. Because it was difficult to understand, the main point is explained. As for asbestos, manufacturing and use have already been prohibited. The problem is Asbestos containing materials that remains in an existing building. The investigation, the analysis, the Asbestos abatement and the disposal procedures were outlined. And it introduced alternative fibers of asbestos.

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This paper, first, explains some features of the inelastic deformation response spectra for the maximum ground motions ever recorded (1995 JMA Kobe NS, 1995 JR Takatori NS, 1994 Sylmar EW and 1985 Mexico SCT EW), using the Japan and U.S. current prediction methods at the same time. The parameters dealt with are periods of SDOF systems, the restoring force characteristics and ductility factors. It is pointed out that the considerably high design strength is required for low & mid-rise buildings to meet the control of building drifts in a remarkable contrast to the case of highrise buildings.
Second, the structural design examples of low & mid-rise reinforced concrete buildings are compared between Japan and U.S., based on the above results. It is emphasized that the use of short columns should be avoided, taking into considerations the balanced layout of structural walls in both the transverse and longitudinal directions in structural design of low & mid-rise buildings in Japan.

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A dynamic collapse test of a full-scale six-story R/C wall-frame building structure was conducted by the world's largest tri-axial shake table “E-Defense” facility. The specimen was constructed based on Japanese design practice in the 1970s. The test was successfully performed, and the specimen collapsed due to shear failure in short columns and structural wall at the 1st story during strong earthquake motion.

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There is a strong demand for non-destructive inspection of reinforcement in concrete structures. It is an emerging issue in Japan because many buildings were built using false earthquake-resistance data. Detection of bar arrangement after completion of construction is attempted in order to verify whether amount of reinforcement was reduced the compared to the design criteria. Non-destructive inspection methods are often used to detect bar arrangement for core boring in order to avoid reinforcement. Radar or electromagnetic methods are often used, and X-ray radiography may be applied if necessary. Radar and electromagnetic methods can also be applied, but only if the cover depth is small. Detection is very difficult when the bar arrangement is complex. X-ray CT scanner using bremsstrahlung X-ray are commonly used for non-destructive inspection of industrial products such as automobile or aircraft components. However, if the X-ray absorption coefficient of a sample object is large, metal artifact presents due to spectrum hardening effect. High permeability quasi-monochromatic photon beam allows acquisition of accurate information about the density distribution of the sample objects. The quasi-monochromatic photon beam is produced by the laser-Compton backscattering from relativistic electrons. National Institute of Advanced Industrial Science and Technology (AIST) have developed a high-energy and quasimonochromatic photon transmission radiography and CT systems. The authors used the radiography system to inspect reinforced concrete structures with deformed bars of different diameters and cracks with precisely controlled width. The applicability of the method was examined, and the quality of the information obtained from the experiment was discussed.

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[in Japanese]

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[in Japanese]

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