Civil engineering infrastructures that were intensively constructed during the high economic growth period have begun to deteriorate rapidly.
 In December 2012, the ceiling panels of the Chuo Expressway's Sasago Tunnel collapsed.
 The Ministry of Land, Infrastructure, Transport and Tourism has announced the year 2013 as the inaugural year of aging infrastructure maintenance and started to implement countermeasures for aging road infrastructures.
 This paper will present the future direction of a public works management system considering of the current situation of maintenance case of road earth structures.

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 In East Japan, the bridge structures face severe environmental condition which induces composit deterioration of salt damage, frost damage and more. The estimation of deterioration rate and the analysis of predominant factors of deterioration would be effective for improving the efficiency of bridge maintenance. To evaluate the deterioration risk quantitatively, two types of survival analysis, Kaplan-Meier estimator and Cox regression analysis, are applied to the periodic inspection data of bridges in East Japan. KaplanMeier estimator is applied to the PC bridge girders' data. The difference of deterioration rate between deterioration mechanisms can be discriminated by the estimator, and degradation tendency can be determined. Cox regression analysis is applied to RC slabs' data to estimate the respective effect of structural and environmental condition on the deterioration. In this analysis, the predominant risk factors are quantitatively explained, and the validity of estimation is assessed by actual inspection records. Furthermore, by comparing the calcurated hazard rate of individual bridges, the actualized or potential risks are evaluated quantitatively. These results demonstrate the applicability of survival analysis to the inspection data, which can introduce the reasonable insight to bridge maintenance.

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 In asset management of infrastructures, it is important to forecast their deterioration conditions. A multistage Weibull deterioration hazard model and its maximum likelihood estimation were developed in 2005 as a deterioration forecasting method considering elapsed years from initial time points. However, this method requires enormous estimation time. Hence a Markov deterioration hazard model, which expresses the deterioration process assuming its time stationarity, has been employed in the majority of practical cases owing to smallness of a computational load. In this paper, the authors propose a Bayesian estimation method (MCMC method) of the multi-stage Weibull deterioration hazard model using a quasi Monte Carlo method in order to reduce the computational load. Lastly, the effectiveness of this study can be discussed in the case study targeting expansion joints.

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 In the periodic inspection procedure of highway bridge, inspection database for the same member and the element been accumulated at the periodic inspection of two rounds. Using the deterioration characteristics of each the member, under the conditions of a typical highway bridge, was quantitatively calculate the risk of a collapse of bridge can be reflected in the fault tree analysis.
 As a result, the difference in the durability performance of each structural characteristics and member I made it clear what to actually how much influence on the probability of failure and collapse scenario. In addition, for the purpose of a reference for optimization of designing bridge structure and rational maintenance method of highway bridges, it was obtained some of the tendency and knowledge to the extent that can be carried out in practice on the significant level.

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 Snow removal is important for the snowy region in winter, in order to provide stable road network service. Most of the private contractors who are in charge of snow removal are small and medium enterprises located in the region. They are reducing their employees and machinery due to decreasing budget for construction project in recent years, which has weakened the ability to respond to snow removal.
 Therefore, an efficient snow removal operation with limited resources is required. Locating snowplows and their working area have often been set by the experience of local engineers, which cannot necessarily make the snow removal operations efficient enough. Therefore, in the future of snow removal operations, it is necessary to aim reduction of snowplows and the cost by making snow removal operation plan based on certain rules. In this paper, we set the management target level that is based on the organized data about the amount of snowfall and the importance of the road, and we show a method for determining how to locate snowplows to achieve the target level.

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 The maintenance of accumulated road stocks has been an important issue in the national land policy in current Japan. It is difficult to continue managing the current state of the road stock with the current budget, taking the prospect for the increase of maintenance cost in the future into consideration. In addition, the road with low importance may be needed to eliminate accordingly in order to decrease maintenance cost because Japan has entered the depopulating society and the smart shrink has been proposed. On the other hand, there will be trouble in the civil life if roads are eliminated recklessly. It is necessary to reduce the amount of road stock strategically, satisfying the demanded movement of citizens. We have proposed a community road network design model that determines the network shape satisfying the constant travel time in community roads. In this paper, we proposed to extend these models to practical applications that enable to consider multiple maintenance strategy, transit mode and timing of evaluation.

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 In the current economy, it is impossible for local municipalities in Japan to maintain all public facilities in good condition. Under these circumstances, it may be more efficient to encourage residents to support maintenance efforts, such as by engaging in daily monitoring. For these reasons, a system of “cooperative road-facility management” whereby road facilities are maintained by various stakeholders including local municipalities, private companies, and residents are proposed. To this end, this paper addresses the subject of resident partnerships involving experts and residents. More specifically, this paper considers the ideal approach for cooperative road-facility management by focusing on social cost analysis. In this model, resident's cost, expert's cost and risk is identified. This paper tends to analysis some cases. As a result, the prospect of the road facilities management is shown by the role of the residents and the cooperative between residents and experts.

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 When considering actions to the Nankai Trough Earthquake or the Tokyo Earthquake, it requires conversion of the way of thinking to “Coastal type earthquake disaster” from “Inland type arthquake disaster”. It is necessary to make the development of law and policies of countermeasures against disaster, a functional assignment in the new framework of the central government and local government, and development of the system in which every government can operate their tasks functionally and efficiently. A concrete measure is building the management system which clarifies structure of the required activities corresponding to a series of disasters from the advance preparations before the disaster and correspondence after the disaster, and performs each activitiess quickly and efficiently.This system needs to be built in the level of the municipality.
 In this study, the municipality disaster management system; it was defined as LGDMS (Local Government Disaster Management System), was tried to construct in the actural Municipality.

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 Contribution of the local construction industry is essential to elimination of road obstacles and repair work of the early period of disaster by severe earthquake. However, in late years, the number of construction machine possessed by constrruction companies tends to decrease by intensification of the competition by a decrease in public construction and the change of bidding method. Minagawa and others examined how rubble processing can be efficient by the cooperation of sorrounding regions in case of Tokai earthquake occures.
 In this article, the authors added the construction machines possessed by lease work corporations and estimated the amount of the rubble produced by an earthquake stood on the East Japan great earthquake disaster. Influenece of construction machine distribution for the effectiveness of rubble processing were discussed based on the simulations with Multi Agent Technology. As a result, it was confirmed that the distribution of the construction machines including leased machines affected the duration to remove the rubbleand especially the initial placement of the leased machines should be estimated properly.

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 Local construction companies that signed disaster relief agreements with the local goverment contributed to the rescue by promptly removing road obstacles for providing transportation after the 2011 Tohoku earthquake. The experience has been highly regarded as a proof of the effective functioning of the disaster relief agreement. Coversely, there have been reports that other disaster relief agreements did not proceed as smoothly owing to poor communication. Learning from the Tohoku earthquake, previous disaster relief agreements should be reviewed. Establishing an emergency response scheme is urgently needed to tackle future disasters. This study deals with effective disaster relief agreements for large-scale natural disasters that require the help of local construction companies.

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 Damage of coming Nankai Trough Earthquake is thought to be larger than Tohoku Earthquake in 2011, there is concern that reconstruction will takes long period. Housing relocation projects of Higashi-Matsusima city after Tohoku Earthquake were analyzed, prototype of Housing relocation projects which is categorized 4 pattern were established in this study. Based on these prototype and damage estimate of Konan city by coming Nankai Trough Earthquake, housing relocation projects of Konan city was established. Then, 4 scenarios reconstruction schedules which have difference whether the municipal government have “pre-earthquake plan for relocation” and “enough temporary pile yard for disaster waste” or not were compared, effectively of these measures were analyzed quantitatively. This kind of analysis method thought to be effective to find out good reconstruction plan by information sharing of reconstruction procedure between municipal government and residents.

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 This study, based on a case study on Southern Transport Development Project (STDP), the first highway-construction project in Sri Lanka, analytically investigates (i) the risks affected people (APs) face in the projects and (ii) the changes in the image or perceptions of APs toward the resettlement or the project.
 Through our household survey, we confirmed that resettlement in STDP was successful in that many APs are satisfied with the project and improved their perceptions. Meanwhile, post-resettlement satisfaction is negatively correlated with resettlers' recognition of Land Acquisition and Resettlement Committee (LARC), which is regarded as successful mechanism for redressing their grievances. We found that this result is driven by the answers from resettlers who are dissatisfied with the staffs and process of LARC.

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 The skill a practician possesses is indispensable in development of production activities of our country. Extinction prevention of a skill is a problem at present. Therefore it's a problem to preserve the ability of the veteran engineer. The way is to analyze a picture. And it's to record practician's skill. This research aims at development of a practician skill maintenance system by an analysis of a picture. This thesis was written about a system development method.

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 Work-related accidents and injuries are estimated to be more common in small and medium-sized enterprises (SMEs). In an attempt to better understand preventive occupational safety and health activities in SMEs, a questionnaire-based survey was performed amongst 47 prefectural labor bureaus.
 The survey reveals that, along with tertiary, manufacturing, and land transportation industries, construction industry has been regarded as one of the most important industries to develop a management initiative on occupational safety and health. In addition, it is proved that risk assessment, health hazard assessment, and safety education are the items highly valued in safety management.
 The result of the survey also shows that safety education is most effective when guidance is provided using following approaches: trainings based on case examples of work-related accidents and injuries; trainings based on examples of improvement; tutorial trainings; seminar meetings consisting of group discussion and presentation; collaboration with industrial associations and industrial accident prevention organizations. The questionnaire result identifies that tools for each operation type and result of detail analysis of workrelated accidents and injuries are expected to be useful for safety education in the future.

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 Understanding and efficiently estimating construction material prices is fundamental to the cost formation of an effective budget for public works. Early inefficiencies in evaluation can quickly develop to impact project risk and significantly impact on project programme and procurement management processes throughout the subsequent construction period. The market prices of materials are subject to regular surveys which give useful benchmark data, however there are time-lags in the production and release of survey data and impacts of unforeseen international (e.g. oil price fluctuations) or local events which can cause significant deviations from tender or budget forecasts and expectations.
 In this paper, we evaluate actual construction material price data accumulated over the last five years, and examine the deviation of the moving average as a potential modelling tool for the prediction of prices within the near future. We validate the model within a relative average error using a multiple regression technique where price prediction is a purpose function that accounts for the current price, market tendency, and the deviation of the moving average. Finally we consider and discuss the likely effectiveness of our proposed price prediction model in reducing the likelihood of tender failures and other impacts on public works projects.

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 In recent years, the design build contract scheme is expanding to use not only the developed countries but also in the developing countries. The design build contract scheme is able to improve project quality, time and cost combing the ideas coming from both design works and construction works. This contract scheme also is able to provide a big chance to contractors and consultants to get out from traditional business way and to increase their project execution ability. It has already started to apply this contract scheme to the public projects in japan. However, contractors do not like to accept this scheme because of unrealistic risk valance between the owner and contractors. The risk valance is the quite essential matter when you discuss about a contract scheme. But in Japan, people have a tendency to mix up tendering scheme and contract scheme. This paper is discussing about the solutions to the problems related to the design build contract in Japan by applying design work layered structure, such as basic planning, conceptual design, basic design, detail design and manufacturing design.

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 The present paper aimed to develop concepts explaining how construction workers acquire and transfer their techniquies. Life stories were collected from a pair of two construction workers: a master and a woker who used to be his pupil. After utilizing the tool of Analytical Worksheet, seven concepts were identifiend. It is expected that a general theory on the process of acquisition and transfer of the techniquies will be described using the seven concepts, although the development of which is a futre task.

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 Due to the reduction of the public works spending and decrease of employees, the number of the local construction company which closes the business will increase. However, the companies take important roles for supporting the community well-being such as the maintenance of the infrastructure, disaster restoration and snow clearance. Thus it is important for the local governments to take measures to improve the sustainability of the companies. In doing so, it is useful if the government can assess the sustainability briefly using commonly accessible information. This study aims to develop the method to assess the sustainability by break-even point analysis (cost-volume-profit analysis) and demonstrates the sustainability of the companies located in Tottori prefecture.

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 As one of the measures for the environmental improvement of the construction industry, it's useful to clarify the division of roles or direct employment. For the latter, the private company is necessary to consider feasible employment plan.
 In this study, to build a model for the direct employment. It is possible to have plans for Long-term employment, deliberate assigned to the project and the age structure of the workers. With this model, the performance of the workers and labor cost of the company are simulated.

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 This report focuses on the safe and effective plant growth regulators, which has been improved under the revised Agricultural Chemicals Regulation Act, and discusses the technique for controlling embankment vegetation with plant growth regulators, as the cost reduction effects of river maintenance by the reduction of public-works spending. In particular, the aim of this report is to solve problems caused by alien plants, which the invasion and growth of alien plants have brought the negative effects for embankment management such as obstacles to river inspection / embankment examine works and weakening of embankment function. The technique for controlling embankment vegetation with plant growth regulators was experimented in Watarase River, and the results showed improved effect against the maintenance problems, around 30% cost reduction in comparison with the existing maintenance cost, and safe to the environment. Therefore, it is thought that the technique for controlling embankment vegetation using the plant growth regulators is applicable enough for the future river embankment management.

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 A large amount of radioactive substances is released by the Fukushima Daiichi nuclear power plant accident, it has spread radioactive contamination around the Fukushima Prefecture. Because of reduction of the radioactive contamination, decontamination project is being carried out by the country under the direct control or municipal order. In this report, as the person in charge of the decontamination operations, which has been implemented from the 2012 fiscal year in the Fukushima Prefecture, Kawamata Town, reports the achievements and challenges of the decontamination operations. First distribution of radiation strength is made higher in the place where gather the rain water even in the same land , also dose difference of by material, explaining that there is a high place locally dose rain trough. Subsequently, reports various decontamination means and describe the result. Furthermore forest area despite the vast, point out the reason why sufficient decontamination is difficult. Last-mentioned evaluation of decontamination effects, I describe problems and challenges in managing the decontamination operations.

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 The development of Preah Vihear and its region depends on many factors from natural resources preservation to human resources. To move into the right direction of enhancing economic growth and social improvement, it is indispensable to keep the first resources from draining out in order to insure their sustainability. In this paper, the authors deal with the development strategy for the sustainable development of this valuable region and discussed the abstract strategy for natural resources and human resources. Protection and management of natural resources including green and underground resources, water resource and land resource are discussed. At last, different touristic activities and program at different time frames are proposed with priority projects.

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 This report is a project whole country's first as the tunnel construction that worked on introduction of CIM after construction start, and this report wrestles with introduction of CIM by our construction and reports contents.

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 The Ministry of Land, Infrastructure, Transport and Tourism has been expanding the application of the overall evaluation bid method, based on the principal of the ”Bill for Ensuring the Quality of Public Works", enacted in 2005, and the method has been applied for almost all the works ordered by the Ministry since 2007.
 The bipolarization was introduced in 2013 to resolve the problems of the overall evaluation bid method and it has been implemented throughout the country. In order to clarify the effect of the bipolarization, survey and analysis using the data of FY 2013 were conducted and this pater reports that (1) it was verified a certain degree of effectiveness for the construction capacity evaluation type and (2) improvement is continuously required for the technical proposal evaluation type.

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