Sewage pipelines are subject to various types of failures caused by different factors. Therefore, much remains unclear about the process leading to road subsidence. This study statistically analyses the mechanism of road subsidence induced by sewage pipe deterioration, focusing on differences in the types of failures. Using data of sewage pipelines in Osaka City, we first employ explainable AI (XAI) to analyze the causes of each failure type. Subsequently, we estimate a survival time model using data on road subsidence induced by sewage pipeline failures to identify the factors contributing to road subsidence. The analysis revealed that (1) failures in sewage pipes occur due to factors specific to each type of failures, and (2) corrosion and joint failure induce road subsidence. This shows the importance of considering the type of failure for the maintenance and management of sewage pipelines.

 Numerous messages have been sent out to society with the aim of raising the status of civil engineers. However, as civil engineers' work values become increasingly diverse and the importance of status varies from engineer to engineer, it is necessary to reexamine civil engineers' perceptions of status. The authors conducted a volunteer satisfaction survey of civil engineers, analyzed their job satisfaction and satisfaction factors, and examined the importance of status among multiple satisfaction factors. The survey results confirmed that civil engineers' job satisfaction is not lower than that of other industries. In addition, among satisfaction factors, the intrinsic factors of job satisfaction, such as job enjoyment and reward, were selected frequently regardless of the respondent's attributes, while the extrinsic factors, such as income, working conditions, and interpersonal relationships, were selected at different rates depending on the respondent's attributes. The selection rate for social status, which represents status, was lower than for other satisfaction factors, indicating the difficulty of positioning one's work in society.

 To adapt to changing socio-economic conditions, infrastructure systems must incorporate sustainability performance, such as decarbonization. Currently, these systems are complex, with interacting hardware and software components. Therefore, treating them as a System of Systems (SoS) to enable holistic optimization is indispensable. Moreover, as reference documents proliferate, transitioning construction production from document-based to machine-readable model-based approaches is also crucial to facilitate the adoption of collaborative robotics, generative AI, and similar technologies. Therefore, this study provides an overview of systems engineering, which is increasingly being adopted in other industries, and reviews existing literature in the construction field. Finally, this study conducts case studies of the application of systems engineering to address the construction management challenges facing infrastructure systems in Japan and evaluates its usefulness.

 This study summarizes basic research into the use of 3D data in the maintenance process, which has yet to make much progress. Specifically, it summarizes considerations of how to utilize 3D data obtained by vehicle-mounted photo laser surveying (MMS) with map information level 500 specifications, which is a general-purpose method for creating digital maps, and LidarSLAM, which performs laser surveying on foot using self-positioning with SLAM technology. It was revealed that while both methods are capable of high-precision surveying, there is a large difference in point cloud density, and it was demonstrated that it is possible to detect and quantify changes in infrastructure by overlaying MMS data, which is being considered for database creation, with LidarSLAM, which can obtain high-density point clouds. In this paper, we describe the algorithm that enables this data processing, and also discuss the results of experiments that examined the magnitude of changes that can be detected and quantified.

 The number of construction workers responsible for the maintenance, renewal, restoration, and enhancement of social infrastructure is decreasing due to the declining birthrate and aging population, and improving productivity at construction sites is an urgent issue. While time-saving effects have been evaluated for individual work types such as ICT earthwork, evaluation methods for overall process shortening effects have not been sufficiently studied.

 This paper aims to propose a perspective for evaluating the process shortening effect of introducing technology, focusing on cast-in-place concrete work, which involves multiple steps such as rebar, formwork, scaffolding, shoring, and concrete pouring. It analyzes the process and work details of construction work using a stationary horizontal jib crane, which is permanently installed on-site and does not require a dedicated operator, using digital data to evaluate the process shortening effect.

 Work is underway to replace the RC slabs of Highway Bridges that have been damaged by fatigue and other factors with PCa PC slabs while traffic regulations are in place.However, since the replacement work involves traffic regulations, it has a significant impact on social and economic activities. For this reason, there is a social demand for a construction method that can shorten the process. In addition, there is a need for infrastructure that is easy to maintain and manage, as well as a response to the shortage of workers and skilled workers. As a solution to these issues, the authors developed the “Cotter Slab Method for Highway Bridges”. In addition, in order to appropriately evaluate the effect of shortening the process of slab replacement work, we attempted to quantify the social benefits using cost-benefit analysis.

 In Japan’s disaster emergency response, governmental agencies utilize established frameworks to enable rapid coordination with local construction companies; however, an excessive burden on these companies remains a critical issue. This study analyzes the current system by focusing on the structural nature of this public-private relationship. It first confirms that, during disasters, the public-private relationship shifts from market-based governance in normal times to organizational governance, thereby saving significant transaction costs, particularly in terms of time. This cost reduction, however, is institutionally incomplete in its guarantees. The study posits that this gap is complemented by implicit selective pressures prompting construction companies to cooperate. These selective pressures are subsequently categorized into five types based on a theory of social power. Finally, the study points out that many of these power mechanisms pose challenges to the sustainability of the system.

 BIM/CIM is useful for the visualization of deterioration rate and for the search of inspection results, so BIM/CIM is expected to improve the productivity of maintenance. However, three-dimensional models of the existing port facilities are rarely made. This study aims to develop the simple and efficient method to make three-dimensional models by parametric modeling. For reducing the cost to make three-dimensional models, it is important that the developed method does not require the site measurement and the skilled modeling work by the professionals. Based on the existing materials such as a maintenance plan and an inspection report, the developed method can make three-dimensional shape data and can set properties for the existing pier without any specialized software.

 In recent years, based on the future visions of various regions, a new approach called "Regional Infrastructure Group Regeneration Strategy Management" has been proposed. This approach strategically manages regional infrastructure from a comprehensive and multifaceted perspective by considering multiple, wide-ranging, and diverse types of infrastructure as a "group." This study proposes quantitative methods for the health diagnostics and deterioration prediction necessary for preventive maintenance in the context of regional infrastructure group regeneration strategy management aimed at future comprehensive private contracting. First, the study presents a quantitative health diagnostic method that ensures high objectivity and reproducibility during inspections of various types of infrastructure groups. Additionally, it proposes a specific method to examine life-cycle cost (LCC) reduction by considering the progression of deterioration (deterioration rate) for preventive maintenance. Furthermore, the study outlines concrete evaluation methods for the effectiveness of extending infrastructure lifespan (long-life measures) through minor maintenance and performance improvements, which have traditionally been applied empirically in LCC reduction.

 This study delves into the contributions of government engineers from a historical perspective regarding the competencies required of those in-house engineers. It raises issues stemming from the hollowing out of technology from project planning to design and estimation, and provides solutions to these challenges.

 Even in advanced Western countries that have reached a mature society, the revival and inheritance of the technological capabilities of in-house engineers are being promoted as important policies. In-house engineers need to oversee and promote national strategic policy issues through collaboration with contractors. As we enter an era of maintenance, management and renewal that cannot be achieved by simply following conventional techniques, more complex coordination abilities, such as prioritizing business tasks, are required than ever before. This indicates that a wider range of technical skills is needed than in the past.

 When local governments implement various policies and projects, including public works projects, they need to prioritize candidate projects due to financial and physical constraints. For this purpose, evaluation criteria are set and methods for scoring and ranking each project are widely used. In particular, the simple additive weighting method is widely used in practice, but this method has been pointed out to have inherent problems. The non-compensatory approach has been attracting attention as a method to avoid these issues. However, although theoretical studies on this method have been accumulated, there are not enough studies on the characteristics of its ranking. In this study, we will summarize the issues with the simple additive weighting method, then focus on a non-compensatory approach that can be used in practice, and clarify the characteristics of its ranking through a comparison with the simple additive weighting method. Based on the results, we will also consider situations in which the application of this method is effective.

 The inherent necessity for renegotiation in construction projects presents challenges including escalating dispute costs and reduced project efficiency. This study comparatively analyzes the relative efficiency of renegotiation under relational and contractual governance frameworks, and investigates the role of Dispute Boards (DBs) and their potential contribution to economic efficiency. The analysis indicates that while both approaches exhibit situation-dependent complementary advantages, a dilemma of inefficient contractual mode selection can arise from strategic interactions between parties. DBs are found to possess unique values, such as efficient dispute resolution and prevention, contribution to project revenue, and facilitation of stakeholder communication, underpinned by factors including procedural flexibility, early intervention timing, continuity, and the fostering of trust. This research demonstrates that, by leveraging these functions, DBs can mitigate the governance selection dilemma and promote the appropriate application of both governance modes, thereby contributing to enhanced project efficiency through the reduction of transaction costs and the improvement of economic performance.

 Foreign engineering consultants have rapidly expanded their global presence through different over-seas expansion strategies including mergers and acquisition. This research uses publicly available infor-mation such as annual reports and interviews to key personnel from engineering consultants to gain an understanding of overseas expansion strategies including cross border M&A strategies and their effects as well as direct investment strategies The analysis found three categories of M&A strategies based on the perspective of the effects on international revenue and diversification. Further, a relationship was ob-served between the base of operations of acquirer and acquiree, as firms were more likely to purchase companies that are based in countries that share a similar language or is located closeby. Through a comparison of cases of expansion through foreign direct investment differences between foreign and Japanese companies were found. Based on these results, possible options for overseas expansion strategies for Japanese companies were proposed.

 Local construction-related companies play an important role in the early restoration of infrastructure in the immediate aftermath of a disaster, and through their activities contribute to minimizing its impact. This paper focuses on how to create an environment in which local construction-related companies can sustain their activities and how to strengthen cooperation, which is essential for an effective disaster response. Currently, cooperation among construction-related companies and the establishment of rules are important for the appropriate allocation of human and material resources in disaster response. However, interviews with construction-related companies have revealed issues such as insufficient information sharing and weak coordination systems. Based on an analysis of the social system environment in which local construction-related companies operate, this paper proposes concrete measures to strengthen cooperation, such as promoting information sharing in disaster response, establishing face-to-face relationships during normal times, and clarifying the division of roles.

 Although Regional Revitalization policies in Japan has made numbers of small and medium-sized municipalities appoint external personnels, there has been insufficient analysis of the actual conditions that lead to success of those appointments. In this study, after reviewing examples of cases in which external personnels are able or unable to fully demonstrate their competences, the key to demonstrate their abilities is to actively try to define their own missions and coordinate with the local governments that have appointed them, given that such small and mid-sized governments are not used to work with such personnels.