Hanshin Expressway Public Corporation Research Articles

Privatization of the Japan Highway Public Corporation: Focusing on Organizational Structure Change†

In October 2005, the Japan Highway Public Corporation was privatized and separated into three expressway companies. Three other public corporations were privatized as well: the Metropolitan Expressway Public Corporation, the Hanshin Expressway Public Corporation and the Honshu‐Shikoku Bridge Authority. The main purpose of this study is to overview the privatization policy taken by the government and to assess the preliminary organizational reforms. We will focus especially on policy issues such as horizontal separation, vertical (management‐holding) separation and regulatory changes, comparing the before‐privatization and after‐privatization periods of the Japan Highway Public Corporation. Evaluations will be based on empirical investigation and theory, as well as on lessons learned from the privatization of the Japan National Railway. † The previous version of this paper was presented at the 46th Congress for the European Regional Science Association, held at the University of Thessaly, 30 August–3 September 2006.

A structure database and its application: Maintenance Information Management System and Bridge Management System of Hanshin Expressway

For efficient management of various structures in a large highway network, systematic handling of data is essential since its volume has swollen over the years and it takes different forms such as diagrams and photos. The Maintenance Information Management System established by Hanshin Expressway Public Corporation (HEPC) is a computerized database and a processing and reference system of all bridge structure elements. As it is a comprehensive application, HEPC is also developing its own version of a bridge management system, which helps to plan annual budget allotments and work prioritization using the life cycle cost minimization rule. Both systems are tools to support a rational decision-making process of maintenance/repair programmes under the recent curtailed financial situation.

Fire protection for TBM shield tunnel lining

Hanshin Expressway Public Corporation is constructing a highway in Kyoto. This highway passes through a heavily populated residential area including two railways and a river. Therefore, this part is planned by TBM shield tunnel. This Fushimi Tunnel is 855 m long and the inner diameter is 10.1 m. The lining of Fushimi Tunnel is originally designed by RC segment and secondary concrete in place. However, the design is altered from the RC segment to thinner steel-concrete composite segment and the secondary concrete lining is omitted. The excavation volume of the tunnel can be reduced nearly 20% by this change, but fire protection measure for the tunnel becomes necessary. The tentative fire requirement for Fushimi Tunnel is that temperature of the lining must be lower than 350 degrees C in concrete and 300 degrees C in steel. This paper reports the results of a fire test done for the composite segment with various fire protection measures. Each test specimen consists of two segments jointed together in the circumferential direction and they are prestressed in compression corresponding to the design load. These segments are identical to the segment to be used for the Fushimi Tunnel. Each segment is 2.5 m long, 1.5 m wide and 0.25 m thick. The fire protection measure applied is board type, silica fiber blanket type and spray mortar type. These specimens are tested under RABT fire curve in which the maximum temperature is kept to be 1200 degrees C for 1 h. This given energy corresponds to about 100 MW. Specimen without fire protection is also tested for comparison. Temperature of the specimen during the test is recorded and the phenomenon of spalling is also recorded by video camera. After testing, the inner face of each specimen is observed. The concrete strength and carbonation depth are measured by cores taken from each tested specimen. Through the fire test, the following information is obtained on the steel-concrete composite shield segment. Spalling of concrete occurs and it reaches up to 60 mm if there is no fire protection on the surface. Compressive strength of the concrete drops to one half of the unheated value and Young's modulus to one quarter by the heating. Carbonation of concrete occurs by portlandite resolution at the place where the temperature becomes over 500 degrees C. The temperature of the steel girder and the joint metal well exceeds the limit of the fire requirement if no fire protection is installed. The sealing material for water tightness is destroyed by fire if no fire protection is installed. All the selected fire protections of the board type, silica fiber blanket type and spray mortar type keep the temperature of the segment less than 260 degrees C. The temperature of the joint metal is kept lower than 100 degrees C and the sealing for water tightness is protected unharmed. It is important to install fire protection on the surface of composite segment such as tested in this study even if fireproof concrete is used for the segment. All the fire protection measures adopted in this fire test satisfy the tentative fire requirement of Fushimi tunnel. (A). Reprinted with permission from Elsevier. For the covering abstract see ITRD E124500.

COUNTERMEASURE AGAINST GROUND FLOW FOR A ROAD BRIDGE (HANSHIN EXPRESSWAY)

Hanshin Expressway Public Corporation has struggled with the restoration and retrofit program for the foundations at Bay-shore Route since the 1995 Hyogoken-Nambu Earthquake. Damage to bored piles and their remediation work are overviewed here. Particularly some of the additional pile methods were discussed as one of the countermeasures against ground flow following the liquefaction.

The Traffic-Control System on the Hanshin Expressway

In 1970, the Hanshin Expressway Public Corporation started operating an automated traffic control system to maximize the total traffic flowing into its expressway network. The corporation has been improving the system ever since. The system relies on two control methods. The first is to limit the cars coming onto the expressway at each entrance ramp to avoid congestion in any section. The system calculates the maximum allowable inflows by solving a linear programming problem once in every five minutes using data from detectors installed along the expressway and at all ramps. The second method is to give drivers the most recent and accurate traffic information about the expressway and its vicinity, including expected travel times and accidents, through various information channels so that they can decide what routes to take. This system is greatly appreciated by the corporation because it is extremely cost effective and also by drivers, who now consider it an indispensable service.

On aerodynamic stability effects for bluff rectangular cylinders by their corner-cut

In this study, a slight modification of the geometrical shape of rectangular cross sections was tested as to its stabilizing effect on galloping oscillation. From each corner of the cross section a square was cut in the expectation that this would have a controlling effect on the separated shear layer generating from the leading edge. The relation between size of corner-cut and vibrational responses was investigated in a series of wind tunnel and water flume experiments. Such corner-cuts were also tested in a full scale model of the pylon members for the cable-stayed bridge which is now being constructed in Japan by Hanshin Expressway Public Corporation.

The Traffic Control System on the Hanshin Expressway - Further Development

Road traffic control systems have become indispensable to the modern society. The Hanshin Expressway Public Corporation, Osaka, Japan started its first traffic control system in 1970 and has been developping it ever since. This paper presents the recent control concept and system configuration of the system together with the expected developments in near future.

MODELING OF VEHICULAR LOADS IN A FULLY CONGESTED TRAFFIC STREAM STATE ON URBAN EXPRESSWAY BRIDGES

In this study, a modeling of vehicular loads in a fully congested traffic stream state on urban expressway networks is presented. The statistical analysis of randomly spacevaring vehicular loads is performed by using the simulation technique and the observed data on traffic streams, provided by the Hanshin Expressway Public Corporation. The parametric analysis for the statistical nature of vehicular loads is done for the various cases of the traffic stream conditions. To demonstrate the effectiveness of the present model, the probabilistic characteristics of the response of a continuous two-span girder to random vehicular loads are calculated numerically by using the correlation theory of random processes and compared with the simulation results.

Traffic Control System on the Hanshin Expressway

The Hanshin Expressway Public Corporation, Osaka, Japan has been operating its traffic control system since the beginning of EXPO '70, that is, March 15, 1970 on its entire expressway systems in Osaka and Kobe. The total length of the Hanshin Expressway is now 79.6 KM and is expected to become 128 KM by 1975. This report presents some features of the control system with emphasis on its hardware system. This system at present has a digital computer, FACOM 270-30, with 65 KW core memory, various peripherals, more than 200 detectors, more than 70 variable information indication devices along the expressway and TV monitoring systems. The control system on Hanshin Expressway is designed to permit future expansions and modifications.