This study aims to validate the seismic deformation analysis for masonry stone walls using the 3D discrete element method. First, two additional cases of inclination tests with small masonry brick stone walls were conducted as a continuation to a previous study. Numerical simulations with reexamined analytical parameters were performed to reproduce the deformations of bricks and backfill cobblestones in the previous cases as well as the additional ones. The results confirmed the validity of the models constructed with spherical clump elements. Next, the spherical clump models were used to conduct numerical simulations for shaking table tests of full-scale masonry stone walls. The results showed that the deformation of masonry stone walls was well-reproduced. Furthermore, the effects of anchors were also quantitatively examined. These results confirm the validity of the deformation analysis used in this study for the dynamic behaviour of masonry stone walls subjected to earthquake ground motion.

 In Japan, many ordinary RC slabs of bridges in express ways are getting over 40 years old and have suffered from deterioration by fatigue due to heavily loaded tracks and simultaneous environmental attacks such as penetration of rainwater, salt of anti-frozen agent and freezing-melting reaction of concrete. Therefore, the express way companies, NEXCO decided to replace the deteriorated slabs into durable PC precast decks in 2015. Based on the loop joint developed by NEXCO having from 30 to 40 cm wide space for concrete casting, same types of reinforcing bar rapping were developed. As those methods are necessary much time for field works, however, shortening of those field works is required. To solve such problems, a mechanical joint called as Cotter joint, which was developed for airport aprons, was employed with scale down reformations. The joint is formed with C-shape cast iron and H-shape key cast iron. Without any reinforcing bar connection, both side precast decks can be connected by the cotter joints with 50 cm intervals and only 20 mm space between both precast panels, Therefore, the field works becomes very short of only bolting of H-shape iron into C-shape iron with simple screwdriver and injection of cementitious material. In the first one-third of the paper, the feature and mechanism of the Cotter joint is introduced. The remains describe the fatigue durability of the precast decks connected with the Cotter joints through the fatigue tests by the wheel running testing method. Extremely high fatigue durability getting over amply the requirement by NEXCO was proved and a useful S-N relation diagram was obtained.

 In both 2020 and 2021, hypoxic water masses were formed in the Ariake Bay from the inner part of the bay to the Isahaya Bay. In 2021, the distribution of hypoxic water masses were observed before and after the freshet of the Chikugo River, indicating that the area of hypoxic water masses have approximately doubled due to large-scale outflow of fresh water. Furthermore, the duration of density stratification due to the freshet was approximately one month, which is longer than the time scale of hypoxia. It is considered that the hypoxic water mass formed mainly in the tidal flat marginal area in the western part of the inner part of the bay expanded further to the southern part of the inner part of the bay due to the large scale fresh water discharge, resulting in the largest hypoxic water mass that was combined with the hypoxic water mass formed in the Isahaya Bay.

 One method to reinforce a caisson is a solidification of filling materials inside the compartment of the caisson. However, the reinforcement effect of the solidification of the filling materials on the load-bearing performance and the stiffness of the caisson wall had not been well-understood. Therefore, this study aimed to clarify the relationship between the structural performance of reinforced caisson walls by solidifying filling materials and the material property and the range of the solidification of the filling materials. For this purpose, we carried out a 1/5th-scaled experimental loading test and a numerical simulation of the loading test.

 The results of this study indicate that it was essential for the reinforcement of the caisson wall to solidify the entire filling materials inside a target compartment. In addition, material properties such as compression strength and Young’s modulus of the solidified material influenced the reinforcement effect.

 Regarding the design of reinforcement of a caisson wall reinforcement by solidification of filling materials, we showed how to evaluate the reinforcement effect and presented the result of a trial calculation.

 The “Act for Partial Amendment of the Act on Countermeasures against Flood Damage of Specified Rivers” was enacted in November 2021. Based on this act, the Hiroshima Prefecture designated the Honkawa River as an urban river in July 2022. The Honkawa River flows through Takehara City and is a Class B river in the Honkawa River system. Majority of the Honkawa River basin is designated for land use . Therefore, this study reports its application to a specific urban river basin and the issues encountered, such as river environment improvement and basin countermeasures.

 The following conclusions were drawn: 1) The Honkawa River flood control plan incorporated the runoff control into the inland water area (land use zone). Therefore, the river and sewerage system planning is needed in the phased future improvements. 2) In basins designated as land-use zones, we are considering land use methods from a wide range of perspectives, including the designation of storage function conservation areas and construction of control areas. Therefore, there is a need to examine countermeasures while aiming to reach a consensus with local residents and businesses.

 The rockfall protection soil embankment is considered a cost-effective and easily implementable solution for mitigating rockfall hazards, provided that there is adequate space alongside roads. This research aims to clarify the fracture behavior of the rockfall protection embankment. The results of weight-impact and static loading tests show that the deformation and failure behavior of the rockfall protection embankment were different under impact and static loading conditions. The damage of rockfall protection embankment subjected impact loading was smaller than the static loading for the same amount of work.

 Laboratory tests of the reliable relative water permeability of bentonite-based buffer materials are required for design and performance assessment of radioactive waste disposal facilities. A controlled-suction permeability test method under steady state is developed and a series of permeability tests for unsaturated sand/bentonite mixture are performed. Numerical simulations for the tests with coupled mechanical-two phase flow model are carried out to confirm applicability of the test to appropriately evaluating the relative permeability. In addition, the Gardner’s method as one of evaluation methods with unsteady permeability tests is discussed based on similar coupled numerical simulations. It is revealed that almost homogeneous water saturation corresponding to given suction and parallelly one-dimensional seepage flow are achieved in the test sample by the developed permeability test. It is found that the test can give reliable relative permeability with such achievement of steady state in the sample, while applicability of the Gardner’s method and attention/importance of setting suction increment according to material properties are suggested.

 Utilizing the street reconstruction for pedestrians invites new activities and rising asset value. The project of “Uptown Normal Roundabout” in Normal town, in the United States of America, is a good example for confirming those effects. This paper has explored the effective spatial design for high project evaluation and implementation system through this project by the document investigation and the interview survey. In the conclusion, this paper highlights two knowledge as a research result. At first, the Uptown Normal Roundabout that have been created by the project of street reconstruction aimed to contribute to the local issues that reduction in street accidents, reducing environmental damage, and creating the central space. Therefore, in the progress of this project, the director of Normal town and the designer opened the candidate proposals to the public and collected the public opinion. After completion, Uptown Normal Roundabout works as a plaza and invited new activities, rising asset value, and improving water storage. At second, in this project, a new position, Uptown Development Director, has been created; and this position worked effectively to create a highly effective public space by managing the progress of the entire redevelopment project, including this project, and supervising the design.

 This paper focuses on the intermodal joint management in Shikoku-island in Japan, where the sustainability of the regional public transport is critical. The philosophy of intermodal joint management in the Land Transport Industries Regulation Act (enacted in 1938) and the two cases of intermodal joint managements, old and new, in Kagawa and Tokushima were overviewed to explore their historical significance. In both cases, local governments coordinated transport operators with each other, strengthened their business foundation, and improved the usability of transport services. Based on this evidence, the paper suggests the need for relational infrastructure among diverse stakeholders in the new MaaS era, and indicates the direction to integrate transport modes into a single service for the enhancement of the social impact.

 Until now, railway facilities have been severely damaged by heavy rains, etc., and it took a long time to recover, and some lines have been abolished. In recent years, abnormal weather has become almost routine, and it is thought that the damage will increase and become more serious in the future. In addition, the new coronavirus (COVID-19) (hereinafter referred to as corona), which spread this year, has greatly reduced the movement of people. And Corona has significantly deteriorated the management of railway operators nationwide, and the abolition of regional railways is becoming a reality.

 In this paper, we examined the impact of such exogenous damage on the railway business from a medium- to long-term perspective, and showed that the impact will increase in the future. Next, we consider regional railways in terms of providing easy-to-use service levels, their sustainability, the rationality of the amount of publicly funded projects, resilience to natural disasters and corona, and early recovery., It was shown that there are problems with the existing vertical separation measures. And we have shown that the public-private shared vertical separation meets all of these requirements.

 With the declining population, the sustainable operation of Japan’s water supply has become an issue, however policy changes are not easy. This study structures the water concession policy process in Hamamatsu City, Shizuoka Prefecture, based on Kingdon’s “Policy Window Model”, and compares it with a sewerage concession implemented in the same city. It was identified that dominant factors include (1) the political nature of water services, which are susceptible to political influence, and (2) differences in problem recognitions amoung actors involved in the policy process, and (3) the political situation peculiar to the policy implementing body. In order for consensus building on policy change in water supply, this study suggests the usefulness of public participation in the problem-setting (agenda-setting) stage to share the problem definition among policy actors and citizens in the sustainable management of water supply, before the policy becomes a political issue.

 In Japan, the number of accidents because of older drivers has increased as a percentage of all drivers' ages, and this has become a social problem. The countermeasures such as the voluntary surrender of driver's licenses are policies that attribute the risk and responsibility for accidents to a single point in time and to a single individual. In addition, since the voluntary surrender of driver's licenses is an irreversible process, the longitudinal process is also a serious problem. In this study, we analyzed the relationship between accidents by older drivers and local environment in Ibaraki Prefecture, assuming that the driving frequency and driving skills of older drivers are influenced over time by differences in the usual driving environment, such as land use, road use, and congestion in each local environment, and that the resulting accidents also differ. As a result, characteristics common to many accidents involving elderly drivers were extracted. Significant correlations were also found between accidents involving personal injury and land use, road width, and other factors, suggesting the importance of accident countermeasures for older drivers according to regional characteristics.

 The location of firms that contributes to the local economy and provide employment is important for the sustainable development of urban areas. While Japanese business community has been claiming that higher corporate tax rates accelerate corporate out-migrations, there are studies that question the validity of such claims. However, these studies do not distinguish between "cross-border expansion" and "cross-border relocation" of business. In this study, we examined the hypothesis that higher corporate tax rates drive the "cross-border relocation" of business by interviewing business persons and conducting a questionnaire survey. The results revealed that corporate tax rates are rarely the main reason for relocating firms overseas, and are less important than other factors such as "capturing overseas demand" and "responding to local needs in foreign countries". It is also suggested that stimulating domestic demand may be more effective as a measure against the out-migration of businesses in urban areas.

 Before the war, a coal loading facility with special equipment was to be built in Jinnampo, Korea, depending on geographical conditions. At the same time, there was no place in Japan with similar or similar geographical conditions, so the construction of coal loading facilities at Jinnampo Port was not possible with conventional techniques. Construction will be done. As a result, the construction of facilities at the port was the first and only pre-war Japan to undergo a series of operations such as planning and construction of pilot facilities. In this paper, we aim to clarify the characteristics of the facilities constructed at Jinnampo Port by clarifying the cases of Western countries and various parts of Japan on the following points and comparing them.

 In this study, based on the interview survey, we wrote a narrative about the efforts of the transport officials of the Tokyo 2020 Olympic and Paralympic Games (Tokyo 2020 Games). Then, we asked university students studying civil engineering and transport, and Tokyo Metropolitan Government (TMG) officials to read the narrative to examine the effects of the narrative on civic pride towards the TMG, patriotism and nationalism. The results showed that the narrative constructed in this study fostered a degree of “pride in the Tokyo 2020 Games”, had a certain effect on fostering civic pride in Tokyo and nationalism, and fostered a degree of pride in the "efforts of the Tokyo 2020 Games transport team". We also showed that the “Tokyo 2020 Games” and “the efforts of the Tokyo 2020 transport team” were the 'loyal patriotism' factor of “a source of civic pride in Tokyo”, and that the “Tokyo 2020 Games” were a source of the 'patriotism' factor.

 As a method of improving construction productivity, the application of conventional Self-Compacting-Concrete can be considered. However, there are problems in terms of cost and ease of manufacturing due to the increase in the types of materials used. Therefore, the authors are developing inexpensive and versatile Self-Compacting-Concrete. In this report, regarding this Self-Compacting-Concrete, the effect of the volume ratio of particles of 0.6 mm or less contained in the mortar and the coarse aggregate volume on the properties of fresh concrete including filling property is clarified.

 Each time a new problem has arisen in the concrete field, solutions have been sought. Although the process of dealing with such problems has been documented in the historical timelines of academic societies, the efforts of companies have not been covered. Therefore, we will use patent information to examine technological transitions, including the efforts of companies. In this study, taking chloride attack as an example of a problem in the concrete field, this study focuses on electrochemical corrosion control method, one of the repair methods used to solve chloride attack. we propose a method that uses the citation relationship of patents as one way to examine technological transition. Moreover, this study will clarify one specific transition of the electrochemical corrosion control method technology and provide basic data for inspiring new developments.

 Being a kind of the civil engineering structures, many underground power transmission tunnels were constructed more than 30 years ago, and the structure of these tunnels are mainly reinforced concrete. It is one of the ways to maintenance such as aging civil engineering structures to accurately measure the stress of reinforcing bars for evaluating the residual strength and planning appropriate repairs and reinforcements. In this paper, we discussed an X-ray stress measurement method that can measure the actual stress without cutting the reinforcing bar, to apply it to steel materials for civil engineering structures.

 The purpose of this study was to clarify the factors that determine the water penetration velocity coefficient and water penetration resistance of hardened concrete using ground granulated blast furnace slag. Therefore, water penetration tests were conducted by changing the drying method and specimen size. As a result, it was confirmed that the water penetration velocity coefficient cannot be uniquely evaluated by properties of hardened concrete such as compressive strength, void volume, and surface air permeability coefficient. However, it was confirmed that the water penetration velocity coefficient was determined by the moisture content inside the hardened concrete. When ground granulated blast furnace slag is used, the hardened concrete has a high water content and produces calcium silicate hydrate with high resistance to water migration. Therefore, it was inferred that the water penetration resistance was improved.

 A transparent evaluation and decision-making process for construction costs is essential for public Infrastructure projects. There are several issues have been pointed out in the Target Price system and its pricing structure. In this study, we focused on the construction cost management system for public works in Japan, and attempted to analyze the actual cost management of the Client and the Contractor from the current law and historical background. As a result, the Client emphasizes the standard estimation used for the Target Price, and the settlement may be performed without emphasizing the cost submitted by the contractor based on the actual situation. The actual cost management is “invisible”, which is different from oversea projects. While the government-led infrastructure export policy is being promoted, it was confirmed the importance of not only the contract management that has been discussed a lot in the past but also the conversion of the cost management system, which has a third party with expertise in construction cost management evaluate bidding prices and assess progress payment at the construction stage, so that the Japanese construction industry will be more transparent in the future. This is an important factor for the future development of the Japanese construction industry overseas.

 With the current decrease in the number of snow removal operators and their aging, the inheritance of snow removal skills and knowledge from one generation to the next generation is facing challenges. To identify how the improvement and inheritance of snow removal skills are structured on the basis of individual experiences, this study conducted a questionnaire survey, targeting snow removal operators and their assistants who are working for a snow removal company in Sapporo City. The survey results show that i) the improvement and inheritance of snow removal techniques are mainly realized on the job site; ii) the frequencies of snow removal operators’ basic and higher skills learning peak in the first and third year of service, respectively, and they decline thereafter; iii) the improvement and inheritance of snow removal techniques are mainly learned through on-site experiences rather than the lessons given by proficient snow removal operators.

 Reservoir is strongly influenced by the inflow river and its watershed, and thus watershed management plays a significant role in the management of water resources in the watershed. In this study, we measured the silica and alkalinity of water collected near the downstream of a predominantly forested watershed to understand the characteristics of soil and base rock in the forest understory and water runoff therein, and analyzed their long-term evolution. The correlation analysis with the slope angle was used to determine the relationship between the slope angle and the water recharge function of the forests. It was found that silica and alkalinity were highly correlated with slope angle, and that silica content is an indicator of groundwater residence time and alkalinity is an indicator of groundwater table level, and that residence time in the soil may increase over time, even taking into account changes in flow rate.