Rapidly deteriorating members are extracted from an enormous amount of infrastructures as the members to be monitored intensively, and it is necessary to constantly monitor, repair, and renew them at appropriate timings. However, there are no systematized methods for extracting rapidly deteriorating members from visual inspection data obtained through routine inspection. In this study, the authors propose a multi-hierarchical mixed Markov deterioration hazard model and its hierarchical Bayesian estimation method. In addition, the authors compare deterioration rates that are hierarchized according to decision making levels, and propose a methodology for extracting the members to be monitored intensively for each level. Furthermore, the proposed method is applied to the joint members of the viaducts of expressways, to discuss the effectiveness of the proposed method empirically.

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 Recently, asset management systems have become the powerful tool that is able to lead to an effective maintenance strategy of civil infrastructures. However, there are some considerations for practical use. This paper presents an approach for modeling the deterioration of tunnel lighting facilities, which consider practical application problems such as a small amount of inspection data. The probabilistic time-based model is used to predict health degree of a tunnel unit. The model is developed using the qualitative condition ratings that are determined through visual inspections to identify the overall condition of tunnel lighting facilities.
 Firstly, this paper explains the simplified dynamic macro model to predict the health degree of tunnel lighting facilities. The model is formulated by master-equation and Markov stochastic process. Moreover, the applicability and validity of the model is shown by illustrating numerical examples using visual inspection data of existing tunnels.

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 Design-Build (DB) is a contract method where design and construction are consistently conducted by the same contractor to reduce the risks conventionally incurred by the contracted by imposing most of those risks on the contractor. The Haneda airport D-runway project was contracted using a DB method, and adopted performance-based design. In this paper, describes case studies to avoid the geotechnical risks due to the design and construction implemented for D Runway, and considers the concept of risk control and countermeasures against the geotechnical risks in DB.

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 In general, steel structures have been corroded locally due to water leakage and so on. In particular, although it is obvious that corrosion at steel girder ends results from water leakage through expansion joints, water leakage from drainage system or cracks in a slab and scattering of de-icing salts also corrode members in steel structures. Application of repair method using CFRP sheet to corroded steel structures have been limited so far since delamination under high stress level or buckling deformation is concerned. As a result, there have been a lot of cases to be difficult to adopt this method for various kind of corrosions. Therefore, we propose a new design method corresponding to the characteristics of steel members and structural details. Herein, low elastic modulus and high elongation putty layer is inserted between the steel member and the first CFRP layer to prevent delamination of CFRP sheet. This paper describes a new repair method and its validation through experiments and analyses.

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 The objective of this paper is to clarify uses and requirements of performance measures/indicators for road maintenance management in the leading countries of New Public Management and gain an insight into how maintenance management should be improved, in prospect of the introduction of benchmarking into and the development of performance assessment in maintenance management of road facilities in Japan. With the recognition that the performance of roads and road administration is easy to understand for the public in maintenance phase, focusing on human-road interface facilities, the paper reveals that management tools such as maintenance criteria and performance standards play an important role in facilitating a management cycle under a two-layer structure consisting of a headquarter and branch offices of road administration.

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