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Kosaka T.,Dia Consultants | Hayashi H.,Japan Civil Engineering Research Institute for Cold Region | Kawaida M.,Central Nippon Highway Engineering Nagoya Co. | Teerachaikulpanich N.,Thai Maruyama Industry Co.
15th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, ARC 2015: New Innovations and Sustainability | Year: 2015

The problems of embankment construction over peat ground with high water content mostly relates to stability, and long-term settlement. Vacuum consolidation method is commonly used to assist the embankment construction over the soft ground for the purpose of accelerating a consolidation process as well as increasing an overall stability of soft ground for a rapidly embankment construction. Theoretically, the vacuum pressure is considered to be a surcharge load applying to the ground. This load will be removed immediately after the termination of vacuum operation. Basically, the settlement after construction can be minimized by waiting the primary consolidation process to complete at the higher degree prior the removal of surcharge resulting in the increase of over consolidation ratio. Nevertheless, the effect of vacuum consolidation as a surcharge load related to a long-term settlement characteristic has not been clearly investigated. This paper presented the measurement of the long-term settlement after the embankment constructions over peat ground assisted by vacuum consolidation. The effect of vacuum operation period was observed based on the field monitoring data. Moreover, the effect of surcharge by embankment and vacuum consolidation method was also studied and compared. It was found that the increasing vacuum pumping period and increasing the amount of surcharge by vacuum consolidation gave a very good performance to reduce the long-term settlement after the construction. Source

Ueda K.,Daido University | Murabe T.,Central Nippon Highway Engineering Nagoya Co. | Nomura H.,University of Electro - Communications | Kamakura T.,University of Electro - Communications
Applied Acoustics | Year: 2014

During the winter, traffic regulations state that automobile drivers must use winter tires on unsafe roads such as snowy expressways. The present report is concerned with the development of an automatic tire identification system that can discriminate winter tires from summer tires with high accuracy. The system detects the impact vibration signal that is specifically generated by winter tires when tread blocks with wide grooves strike the road surface during rolling. The signal is picked up by a commercially available vibration sensor. If the signal contains specified impact frequency components, the tire is judged to be a winter tire. Compared with the previous identification system, which used airborne tire/road noise, the proposed system has two advantages. First, it is unaffected by meteorological factors such as wind noise. Second, the proposed system performs well even when the target vehicle is traveling at low speed. We evaluate the performance of the system outdoors using a number of vehicles with various tires and demonstrate an overall improvement in identification accuracy for vehicles traveling at low or moderate speeds. © 2014 Published by Elsevier Ltd. Source

Suzuki T.,Central Nippon Expressway Company Ltd | Moriyama M.,Central Nippon Expressway Company Ltd | Hira T.,Central Nippon Highway Engineering Nagoya Co. | Kimura S.,Kanazawa Institute of Technology
Life-Cycle of Structural Systems: Design, Assessment, Maintenance and Management - Proceedings of the 4th International Symposium on Life-Cycle Civil Engineering, IALCCE 2014 | Year: 2015

In the operation and management of expressways, it is of importance to specify the service level in consideration of safety, reliability, and comfort of expressways, and achieve that level. The service level of structures constituting expressways, such as bridges and tunnels, as well as facilities will become clear once performance requirements are established. Moreover, achievement of the service level will be possible by understanding system risks through the clarification of the relationship between individual structures and facilities, and then developing an overall management system and reinforcing the system for its continued improvement. Focusing on tunnel structures on expressways and the related facilities, this paper proposes a method for setting performance requirements for tunnel structures and facilities in accordance to the service level of expressways as well as a method for analyzing system risks using the established performance requirements. © 2015 Taylor & Francis Group, London. Source

Aoyama M.,Central Nippon Highway Engineering Nagoya Co. | Miyazato S.,Kanazawa Institute of Technology | Kawamura M.,Kanazawa University
International Journal of Corrosion | Year: 2014

Chloride induced-corrosion of steel bars in concrete can make cracks and exfoliation in near-surface regions in reinforced concrete structures. In this paper, we described the basic concept and practice of steel bars corrosion protection method by the combination of galvanic anode (zinc wire) and the penetration of nitrite ions from mortar layers containing a large amount of lithium nitrite. © 2014 Minobu Aoyama et al. Source

Shintaku A.,Central Nippon Expressway Company Ltd | Okubo F.,Central Nippon Highway Engineering Nagoya Co.
19th Intelligent Transport Systems World Congress, ITS 2012 | Year: 2012

Ichinomiya traffic control centre operates 12 expressways of 822 km which has various characteristic s in Tokai area. These expressways passing urban and rural area have more than 600 CCTV cameras on those routes. Although the traffic control officers in the control centre need to deal with various traffic events quickly, some of them don't have experience enough to manage that. In order to support such officers, the image processing detection system has been installed in some part of the expressways, e.g. tunnel. In addition, some companies have developed technologies of image processing to detect emergency events. However, those developing system and developing functions don't work efficiently very much because developers and manufacturers don't know the true needs for the traffic control centre. The road operating company usually make a request for accuracy of count the number of the car and accuracy of the detecting speed when they give out the order. There are not enough specifications and requirements for detecting the emergent event and they don't have the way to verify them. In addition, the road operating companies didn't give them the information in the traffic control centre for security and difficulty to coordinate one with other authorities. This paper reports what traffic control officers want to know quickly the most when traffic accidents occur, in other words which detection of image processing is really helpful, and which detect function should be developed for them. Moreover, this report disclose the information of the traffic control manager's demand, the information become a key to improve the human-machine interface of the control system. Source

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