This paper describes the European standardization and conformity assessment scheme in terms of construction products and performance-based design, which faithfully carries out obligations requested by the WTO/TBT Agreement. The author recognizes on these points that (1) current Japanese certification scheme for products including requirements for certification bodies are fairly similar to the European one, and (2) Japan can take a leadership rolein laying down the redefinition of performance-based design and requirements of design validation bodies.

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  The effective washing of bridges unquestionably extends operating life for bridges. This practice of adopting bridge washing techniques has been practiced within the U.S.A. for considerable time; however, few data currently exists pertaining to adhered material found on bridges, respective washing methods regarding such, and quantitative data concerning the results. Therefore, in an effort to achieve greater understanding of the aforementioned for bridges in cold areas where anti-icing measures are the norm and where vast snow accumulates, we have performed investigations on test pieces regarding the removal of staining and salt adhesion, on bridge life extension effects, and on bridge washing techniques. As a result of our experiments, it was determined that the top surface of the lower flange encountered considerable staining and salt adhesion. By employing simple moveable scaffolding we were able, via washing, to effectively remove the staining and salt adhesion. Moreover, by adopting improvements in waste water collection and the actual washing techniques, we were able to satisfy waste water regulations, confirm bridge life extension merits, and confirm the practical application of bridge washing techniques is possible.

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  This paper proposes an approach which couples human sensibility and mechanics for the design of underground space shapes. A questionnaire is adopted as a method to assess the preferable shapes for underground spaces from the viewpoint of human sensibility. On the other hand, a new index for assessing the preferable shapes from the viewpoint of mechanics, called "mechanical sensitivity", is defined. A method for designing the shapes, which couples human sensibility and mechanical sensitivity, is described here. In order to verify the proposed method, one example of a shape design for underground space is demonstrated.

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  For constructing a maintenance scheme of an existing bridge, the methods for estimating the weights of heavy trucks on highways are needed, and Bridge-Weigh-In-Motion (BWIM) has attracted many researchers. A standard BWIM is based on the measurements of strains at lower flanges and transverse stiffeners of main girders. In the present study, BWIM only by the strains at transverse stiffeners, which is therefore simple and more economical, is proposed. It is based on the integral BWIM and is named "BWIM by Integration Method with Transverse Stiffeners (BWIM-IT)". Its accuracy is investigated using the data of field test. In most cases, the accuracy is satisfactory from a practical viewpoint, except when trucks run in parallel in two lanes in the down-lane bridge. The problem is found attributable to a cross girder and/or a cross frame distributing loads between main girders. It is then demonstrated that the accuracy can be improved if the transverse stiffeners on which the influence of truck loads in the adjacent lane is small are used. The study then concludes that the proposed BWIM-IT can achieve the accuracy as good as the standard BWIM, provided that appropriate transverse stiffeners are utilized.

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  It is a world-wide tendency for water supply industries to introduce more private participation in the project scheme. In addition, there are wide variations in terms of risk allocation between public and private sectors. However, few attempts have been made to conduct quantitative risk assessment with regard to the risk allocation. The aim of the present study is to build a quantitative risk analysis system to find the best project scheme among candidate ones, full privatization, concession, PFI, outsourcing, etc, with the variation of risk allocation. With the case studies, it is confirmed that the system built in this study is equipped with the functions to provide effective information from the viewpoints of both Value for Money for the public and the viability of the project company.

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  The new technology has been developed to establish the more reliable excavation control protocol to ensure cutting face stability. The new technology is consisted of development of measuring device (flappers) of muck flow inside the chamber and numerical analysis to evaluate the status of plastic muck flow.
  Flappers were installed in the chamber of the shield machine and torque on the flappers was measured. Then, the numerical analysis was conducted to satisfy the data obtained in the field. Once the numerical analysis was established, the condition of the muck flow in the chamber could be evaluated by the analysis.
   As the result of field application, it is verified that this technology is useful to grasp the status of the muck flow inside the chamber and to control the muck flow in the chamber.

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  Spiral steel pipes are relatively economical compared with bending roll pipes which are commonly used as steel bridge piers of highway bridges because they are produced in large quantities in factories. However, the mechanical features of spiral steel pipes including seismic performance may be different from those of bending roll pipes. In this study, cyclic loading experiments and FEM analysis were conducted for grasping the elasto-plastic behavior of hollow spiral steel pipes. Based on the experimental and analysis results, the seismic performance of hollow spiral steel pipes under compressive axial force and cyclic bending moment were examined and it is found that the seismic performance of hollow spiral steel pipes are similar to that of hollow bending roll pipes and it is possible to evaluate the seismic performance hollow spiral steel pipes adequately by the seismic evaluation method described in the seismic design specifications for highway bridges.

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