Hanshin Expressway is the 233.8 km long expressway network in Osaka-Kobe area consisted mainly of viaduct structures. Starting from only the 2.3 km section in 1964, the network has been expanded to the one covering the whole area and now accommodates more than 900 000 vehicles per day. Since it is one of most important transportation infrastructures in the area, the highest level of maintenance quality is always required and we have met the need by developing many efficient maintenance methods. However, even the vast amount of structures are aging and rapidly deteriorating, the further rationalization of the maintenance activities is demanded to fulfill the goal of 30% reduction of maintenance budget set after the company’s privatization in 2003. This paper introduces Hanshin Expressway Bridge Management System (H-BMS) which is a custom-made tool to evaluate the effects of such budget restriction against structural quality as well as to help construct an appropriate medium or long-term maintenance plan. Also, it explains about the methodology of setting a quantitative performance standard for routine maintenance works using Hanshin Expressway Logic Model (HELM).

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The circumstances of the maintenance of the social infrastructure have changed greatly to the current era now that local residents' agreement and cooperation is obtained. In the past, infrastructure design done by engineers and experts usually could not reflect the intention of real users, and it was not well discussed in terms of the standard design, either. Using SD (Semantic Differential) evaluation method, this research verified the plan and the process of the design for Izumisano Tollgate on the highway to the Kansei Airport by comparing the design which general user evaluated with the decided one by a governmental design department. The new tollgate design by the authors was based on the opinions and suggestions of civil engineers and experts. As a result, the newly designed plan for the tollgate was found to be more appropriate than the previous official one.

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In order to use the corrosive protection characteristic of a weathering steel bridge effectively, it is very important to understand the corrosion factor and rust mechanism. In this paper, the relationship between rust level of weathering steel bridge and structural property, geographical data and meteorological factors was analyzed. From the results of Quantification Method 1, rust level is influenced by not only distance from shore but also rainy days and average temperature. Prediction of rust level using regression coefficients obtained from Quantification Method 1 was also carried out. Estimated rust level was suited well for the investigation results of bridges in Kyushu-Yamaguchi region.

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This study presents an experimental study to elucidate the dynamic response of railroad ballast subjected to seismic loads. A series of shaking table tests for ballast and gravel was performed. In these tests, a one-third scale model of railroad ballast as well as a full scale model was used. Based on test results, the seismic stability and ductility beyond failure of railroad ballast are quantitatively evaluated. Moreover, effects of the scale factor between prototypes and the models on the dynamic response of granular materials are discussed. This study proposes an evaluation method of seismic performance of railroad ballast by small scale model tests.

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This study presents an experimental study to elucidate the dynamic response of railway track structures subjected to horizontal seismic loads. A series of shaking table tests for one-third scale models of ballast track and grouted ballast track was performed. Based on test results, the seismic stability and ductility beyond failure of railroad ballast were quantitatively evaluated associated with the observed movement of ballast particles inside railroad ballast. As the results, an evaluation method of seismic performance of railway track was proposed correspondent to magnitude of earthquake motions, and it was revealed that the difference in track structure had a serious influence on the seismic performance of railway track.

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In order to improve the reliability of displacement measurements, using the Global Positioning System, it is an essential task to detect the exact displacements from measurement data scattered among various types of errors. This paper discusses the atmospheric delay caused by changes in weather conditions as an important factor in the measurement errors, and proposes an error correction method for it. A computer program is developed, and it is applied to practical measurement results in order to verify the proposed method.

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This paper describes an examination of plume behaviour in a small section tunnel by means of 3-dimensional simulation. We confirmed the validity of present simulator for small sectional tunnel in comparison to the 1/3 scaled model tunnel fire tests. The maximum heat(convection) and smoke release rate of a passenger car fire were derived 1.8MW and 9g/s respectively compared between simulation and experiment of passenger car fire in the tunnel. As a result of the simulation of the passenger car fire for a small section road tunnel, we clarified that the smoke transfer is not over 1m/s. However, the smoke is easy to diffuse by the large effect of temperature fall of the plume compared to ordinary cross section.

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During constructing the cut and cover tunnel, the brace may be removed by “The method of replacement of brace reaction using side wall”. However, the evaluation for the structural stress in case of applying this method is not clear at this moment.
In this paper, we propose the design method of the cut and cover tunnel when the brace is removed by this method.
This design is the method of calculating the residual stress that is relaxed by creep characteristic of concrete after a long period of time.

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The authors have developed "Segments combined with Secondary Lining for Sewerage Shield Tunneling Works". The segments are manufactured with a corrosion protection layer of 50-mm thick non-reinforced concrete at the inner side, which aims at reduction of construction period and costs by omitting the secondary lining construction process. In this research, load carrying performances of the segment under possible loading cases including the thrust force of shield jacks were measured and compared with segments without secondary lining. In addition, durability of the corrosion protection layer was confirmed by the exposure tests to hydrogen sulfide gas. A new type of joints which can make smooth inside surface has developed for additional cost reduction and the performances of the joint were verified. Guideline for design and construction is provided for the practical use of the segments.

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