West Nippon Expressway Company Ltd NEXCO WEST

Kita-ku, Japan

West Nippon Expressway Company Ltd NEXCO WEST

Kita-ku, Japan

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Hiasa S.,University of Central Florida | Hiasa S.,West Nippon Expressway Company Ltd NEXCO West | Watase A.,West Nippon Expressway Company Ltd NEXCO West | Birgul R.,University of Central Florida | And 4 more authors.
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

The aging of road infrastructure is becoming a serious problem worldwide. Although the number of aged structures is increasing rapidly, inspection and maintenance for them cannot catch up with the speed due to the limited budget. Under these circumstances, infrared thermography method has been developed as one of non-destructive evaluation methods to implement inspections efficiently and effectively. This study is focusing on exploring enhancing the usability of infrared method as a viable non-destructive evaluation technology. In this research, infrared technology was applied to existing structures to prove the reliability and usability as a non-destructive inspection, and an experimental study was conducted to determine the most thriving time window to collect useful data from an object by using an infrared camera. Three infrared cameras with different specifications were also utilized both in a lab test and on an existing bridge. The results have shown that infrared thermography could detect subsurface anomalies in an existing bridge, and also indicated that night time was a better option to gather data from an object. The results of camera comparison showed the efficiency of the infrared thermography technique for bridge inspection although there were some discrepancies due to different camera types. © 2015 Taylor & Francis Group, London.


Sakamoto H.,West Nippon Expressway Company NEXCO West | Tada M.,Kinki University | Iida K.,Osaka University | Noma H.,Ritsumeikan University | And 4 more authors.
20th ITS World Congress Tokyo 2013 | Year: 2013

Although rapid aging of popularity causes serious traffic problem in Japan, only few studies have been conducted to investigate elderly drivers' behavior especially on expressway. Our statistical analysis of accident records on expressway in past five years showed that (1) toll barriers (TBs) are highly accident-prone (2) a typical pattern of elderlies' accidents is significantly different to that of non-elderlies' on TBs; while characteristic pattern of elderlies' accidents is "side-by-side collision caused by drivers' lack of scanning for checking safety of backside", that of non-elderlies' is "rear-end-collision caused by eye glance behavior while driving at TB gate". However, whereas accident records analysis gives us approximate information about elderlies' accidents, it gives us no detailed information about traffic environment or drivers' behavior. Therefore, in this study, to know detailed information about traffic environment on TBs, we analyzed 845 vehicle trajectories on an accident-prone TB using video-based approach and detected potentially dangerous spots where traffic conflicts frequently occur. Then, to know how elderly drivers behave at the detected spots, we performed an experiment in real traffic conditions using 40 subjects (26 elderlies and 14 non-elderlies). In our study, we let each subject drive the expressway including the TB and measured his driving behavior using multiple sensors (eye camera, video camera, etc.). After finished driving, to know how each subject perceived risk while driving, we interviewed each subject by showing videos of his own driving behavior recorded in the experiment. As a behavioral approach, we evaluated and scored each subject's safe driving skill for preventing accidents based on driving instructors' knowledge using measured sensor data. The result of driving behavior evaluation was that elderlies' safe driving skill score at the potentially dangerous spots on the TB is significantly lower than that of non-elderlies'. In addition, to know why elderlies' behave riskily on the TB, we analyzed subjects' interview data and evaluate each subject's risk perception ability (psychological approach). The evaluation result of risk perception ability shows that even at the potentially dangerous spots on the TB where traffic conflicts frequently occur, elderlies' could not perceive risk appropriately.


Hiasa S.,University of Central Florida | Hiasa S.,West Nippon Expressway Company Ltd NEXCO West | Birgul R.,University of Central Florida | Birgul R.,Muǧla University | And 4 more authors.
Computing in Civil and Building Engineering - Proceedings of the 2014 International Conference on Computing in Civil and Building Engineering | Year: 2014

The aging of highway infrastructure is a serious problem worldwide. As important constituents of this infrastructure, bridges have usually been inspected by visual inspection techniques and hammer sounding methods. In addition to these existing methods, different non-destructive evaluation technologies are also being developed and are expected to be utilized for effective management of highway structures. This study focuses on exploring and enhancing the usability of infrared thermography as a viable non-destructive evaluation technology. In this research, an experimental study was conducted to determine the most thriving time window to collect data from an object by using an infrared camera. The same setup was utilized to obtain data from existing structures. The results have shown that the night time was a better option to gather data from an object. It was also observed that infrared thermography could detect subsurface anomalies. © ASCE 2014.


Hiasa S.,University of Central Florida | Hiasa S.,West Nippon Expressway Company Ltd NEXCO West | Noori M.,University of Central Florida | Kelly C.,University of Central Florida | Tatari O.,University of Central Florida
Journal of Cleaner Production | Year: 2015

The Shin-Meishin Expressway is being constructed from Nagoya to Kobe in Japan, and the section from Takatsuki to Kobe is currently under construction as a viable alternative route as opposed to the Meishin Expressway. However, highway construction is usually considered destructive to the natural environment due to the deforestation required during construction, as well as subsequent increases in CO2 emissions upon completion of new highways as new traffic is brought to the area. By applying a system dynamics methodology with respect to the Meishin and Shin-Meishin Expressways, this study analyzes two major effects of new highway construction (CO2 absorption and CO2 emissions) as well as the potential influence of felling, replanting, and/or maintaining the surrounding forest area on the overall CO2 absorption capacity, net CO2 emissions, and total CO2 stock in the analyzed construction area. Regarding CO2 absorption, it was found that, if the portion of the forest felled during construction is very old, new highway construction can help to recover the lost CO2 absorption capacity by planting new trees along the highway, even if the area of planting is much smaller than the area of felling trees. As for CO2 emissions, it was found that mitigating traffic congestion and decreasing the required driving distance can reduce CO2 emissions from the highway(s) in question. Therefore, this study concludes that new highway construction does not always harm the environment regarding CO2 pollution, as the harmful impacts commonly associated with highway construction can be mitigated with other technological and/or ecological mitigation methods. © 2015 Elsevier Ltd.


Watase A.,University of Central Florida | Watase A.,West Nippon Expressway Company Ltd NEXCO West | Birgul R.,University of Central Florida | Birgul R.,Muǧla University | And 5 more authors.
Construction and Building Materials | Year: 2015

Infrared Thermography (IRT) is one of the nondestructive inspection techniques to detect delaminations in concrete bridge decks. These defects are identified by capturing the temperature gradient of concrete surfaces. In order for this technique to be effective in damage detection, IRT inspections should be conducted at certain time windows with favorable temperature conditions to get clear temperature gradients on inspected surfaces. This study is an experimental work examining the effects of ambient environmental conditions at different times of a day to locate subsurface delaminations and voids at a shallow depth, which is an additional influencing factor. This study also attempts to figure out a relationship between ambient environmental conditions and the temperature values of concrete surfaces to estimate the best time window with appropriate environmental conditions for IRT inspections. To this end, specially designed reusable concrete test plates with different thicknesses were manufactured to collect thermocouple sensor readings. Multiple regression analyses were employed to generate prediction models that seek a relationship between environmental conditions and temperature gradients on the test plates attached to a target bridge. Regression models also utilized sensor data collected at another location different than the target bridge location. It was found out that the most important aspect of sensor data collection was to accomplish a perfect contact of test plates with concrete bridge deck surfaces to get discernible temperature gradients. When this condition is not met, data analyses yield spurious results leading to futile conclusions. On the other hand, it was also observed that prediction models generated by regression analyses followed the same pattern as that of sensor readings. This makes it possible to have prediction equations based on sensor readings to determine suitable time window for conducting IRT inspections. © 2015 Elsevier Ltd.


Hiasa S.,University of Central Florida | Hiasa S.,West Nippon Expressway Company Ltd NEXCO West | Birgul R.,Muǧla University | Birgul R.,University of Central Florida | Catbas F.N.,University of Central Florida
Journal of Civil Structural Health Monitoring | Year: 2016

A detailed investigation of infrared thermography (IRT) for civil structures is presented by considering different technologies, data analysis methods and experimental conditions in the laboratory and also in the field. Three different types of infrared (IR) camera were compared under active IRT conditions in the laboratory to examine the effect of photography angle on IRT along with the specifications of cameras. It is found that when IR images are taken from a certain angle, each camera shows different temperature readings. However, since each IR camera can capture temperature differences between sound and delaminated areas, they have a potential to detect delaminated area under a given condition in spite of camera specifications even when they are utilized from a certain angle. Furthermore, a more objective data analysis method than just comparing IR images was explored to assess IR data, and it is much easier to detect delamination than raw IR images. Specially designed laboratory and field studies show the capabilities, opportunities and challenges of implementing IRT for civil structures. © 2016, Springer-Verlag Berlin Heidelberg.


Hugenschmidt J.,University of Applied Sciences Rapperswil | Kasa C.,VAP | Kato H.,West Nippon Expressway Company Ltd NEXCO WEST
Near Surface Geophysics | Year: 2013

Industrial railway tracks are important for the loading and unloading of goods and therefore for the railway system in general. Often, industrial tracks are embedded in concrete and/or asphalt to enable trucks and other traffic across rails. Thus, most of the construction is hidden from visual inspection. If repair work is planned or if damage occurs, details of the construction have to be known for the planning of repair work and for the evaluation of damages. This paper describes the characteristics of industrial railway tracks, frequent problems and the non-destructive testing on several real sites using GPR. Typical testing problems, most of them related to construction details, are described and the application of GPR for these problems is demonstrated using data from field measurements. Data from different types of equipment are compared and benefits and limits of the method are discussed. It is shown that GPR can provide information that is required to address problems that can be found frequently on industrial railway track sites. © 2013 European Association of Geoscientists & Engineers.

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