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Before the anticipated Nankai Trough earthquake, the effects of multiple cascading hazards on bridge performance and the associated functionalities of road networks must be assessed to develop recovery strategies. This paper presents a framework for assessing the probabilistic connectivity of road networks exposed to both ground motion and tsunami, considering the spatial correlations among hazard intensities. To evaluate the joint probabilities of bridge states (i.e., passable and impassable states) and the probabilistic connectivity of road networks, the total probability theorem was used to integrate spatially correlated seismic and tsunami hazard assessments into the fragility estimates that consider the cascading effects of ground motion and tsunami-induced damages to bridges. For illustrative purposes, the probabilistic connectivity of hypothetical road networks in Japan that could be affected by both ground motion and tsunami during the anticipated Nankai Trough earthquake was assessed using the proposed method. The results showed that seismic retrofitting of bridges located along the route where the probability of impassable states due to tsunami is very low can enhance the probabilistic connectivity of entire road networks. [ABSTRACT FROM AUTHOR]

Coordinating a wide range of organizations is crucial for disaster management. This paper reviews the coordinating mechanisms of disaster management in Japan, in particular focusing on the relationship between national and local governments. While local governments have the principal responsibility of managing disasters, they often have limited capacity and experience in disaster management. Furthermore, they are often overstretched with the various tasks of response and recovery. Supporting local governments from the outside and coordinating such support activities are essential in mitigating disaster damage. This paper examines (1) coordination mechanisms, and (2) actual coordinating efforts of response and recovery in recent disasters such as the Great East Japan Earthquake and Tsunami in 2011. It was found that Japan is evolving in coordinating mechanisms by learning from disasters. The national platform of coordination was established over 50 years ago. Similar platforms were established at the local level as well. Each national agency has established and strengthened the supporting teams of response and recovery efforts in affected areas. Local governments outside the affected areas also provide support to affected governments according to pre-agreement. [ABSTRACT FROM AUTHOR]

This paper describes the state of the art of structural steel reuse in Japan. A significant part of the material is taken from a document titled the Architectural Institute of Japan (AIJ) Recommendations for Sustainable Steel Building Construction (Draft) available only in the Japanese language. The motivations for and potential benefits of steel reuse are examined. The affinity between seismic design requirements and steel reuse is highlighted through a concept known as "damage-control" design. Some technologies for disassembly are introduced. The historical development and changes in Japanese structural steel are summarized, followed by a discussion on reusability of historical steel reclaimed from existing buildings. Reuse projects whose details are known to the authors are listed. The heart of the paper is a design procedure that specifies the structural engineer's role and involvement in planning, material procurement, and executing a steel reuse project. The discussion is concluded by six directions that should be pursued to make steel reuse a widely accepted reality in Japan. Among those directions are research needs to establish a procedure to quantify the remaining structural performance of reclaimed steel considering possible exposure to earthquakes, establish connections that allow for easy disassembly, and introduce modularized structural systems. High seismicity and the general practice to adopt full moment frames pose unique challenges for steel reuse in Japan. [ABSTRACT FROM AUTHOR]

The rapid growth of urban populations and the environmental concerns associated with this growth challenge city planners and developers to consider more sustainable building systems. In Japan, the recent change in the law governing building standards and introduction of cross-laminated timber (CLT) offer the prospect of a further extension of the height of timber buildings to the high-rise category. Because of that, many researchers have begun to research the possibility of hybridizing CLT with steel-framed structures to increase the performance of buildings utilizing CLT. This paper presents the test and numerical results of cyclic loading experiments performed upon CLT shear wall infilled hybrid steel frames with concealed metal plates and drift pin (DP) connections. For the failure modes of the tests, shear failure of CLT at around 1/50–1/30 rad were observed in almost all specimens, except the specimen with slender steel beams, which led the CLT to out-of-plane deformation. The load sharing effect between two components were also evaluated, showing that the steel and CLT infill worked closely together to resist the lateral load. After the experiments, a numerical model was developed using the nonlinear finite analysis software SNAP V7.0 to predict the results of the experiments. The model was developed based on the results of element tests conducted previously, was validated using the test results, and can potentially serve as the basis for an appropriate form of methodology with which to design future CLT-steel hybrid structures for service in seismically active regions. [ABSTRACT FROM AUTHOR]

The deployment of wireless sensor network (WSN) for continuous seismic monitoring system of cable-stayed bridge is presented in this paper. A newly developed WSN that is based on simultaneous high-speed concurrent transmission flooding technique was implemented on the Shin-Nakagawa Bridge, a 530-m single-plane, single-pylon, steel box girder, cable-stayed bridge in Ibaraki prefecture, eastern Japan. The structure is seismically isolated with laminated rubber bearings at the main pylon and piers. Some isolation bearings were partially damaged by the 2011 Great East Japan (Tohoku) earthquake. As a part of monitoring, a WSN with a total of 26 sensor nodes were installed at several locations on the piers, main pylon, girder, and ground. This paper describes the WSN system, the monitoring scheme and procedure, analysis of recorded seismic responses, and their use for structural assessment, especially the performance of isolation bearings during earthquakes. The monitoring system successfully recorded structural responses from 63 earthquakes in the 45 months monitoring period between August 2017 to December 2020, which include the responses from near-field and far-field earthquakes. The comparisons of recorded ground motions with existing nearby seismograph have shown the accuracy and reliability of the WSN. Modal parameters of the bridge were successfully determined from the seismic responses obtained from the WSN using multi-input multi-output time-domain system identifications. Characteristics of seismically isolated bridge responses, such as high-frequency filtering effect and decoupling effect of the girder responses, can be clearly observed from the records of the large earthquakes. [ABSTRACT FROM AUTHOR]

Increasing attention is today being focused on the issue of dispute resolution in the Japanese construction sector. Disputes were infrequent under the traditional contract agreement system. However, against the background of a shrinking construction market, owners, contractors, builders, engineers, subcontractors, and suppliers are seeking higher profits and are increasingly asserting their rights, resulting in the creation of an adversarial environment in the industry. It is not generally known outside Japan that the term “claim” has traditionally been used in the nation’s construction industry with an entirely different meaning to its use in other countries. This paper discusses unique characteristics of the implementation of construction work in Japan that are representative of this different use of terminology. These unique characteristics are considered as the result of a business culture that has developed through a combination of historical circumstance and the specific characteristics of Japan’s construction market. The paper also examines the mechanism of dispute resolution, and considers specific details and changing trends in construction disputes using relevant statistical data. [ABSTRACT FROM AUTHOR]

In Japan, the number of houses available exceeds the demand in all prefectures. Improving housing quality has gained importance over building new dwelling stock. The thrust of housing policies and programs in Japan is to improve housing quality. Housing quality is a very loosely defined term, and there is no consensus in the housing literature on its measurement. The present paper proposes the use of the hedonic approach to estimate a quantifiable measure of housing quality in the Tokyo Metropolitan Region (TMR). The objective of this paper is to compare housing quality in the five prefectures of the TMR and among six tenures of housing choice. The results indicate that the condition of rental housing in general is poor. [ABSTRACT FROM AUTHOR]

The uncertainty in walking and waiting transfer times at transit stops depends on the environmental conditions, vehicle schedule punctuality, and variations among individuals. Relying only on the mean values ignores such uncertainty and leads to improper transfer coordination. This paper provides a general framework to estimate the time distribution parameters of walking and waiting based on automatic-fare-collection data under the assumption that the distribution function is known. The proposed methodology contributes to the existing literature by providing a stochastic frontier model (SFM) that is adaptable to transit assignment models. The normal/exponential SFM is utilized to estimate distribution parameters based on the maximum-likelihood method. The methodology was applied to smart-card data from Japan to estimate the transfer walking- and waiting-time distributions between bus stops and rail stations. The results indicate a low disturbance in the observed data for walking time and that our assumptions regarding walking-time estimation were reliable. Furthermore, we quantified how the waiting time at a bus stop depends on variations in the service headway. These findings are expected to help in making more informed decisions to optimize transit schedules. [ABSTRACT FROM AUTHOR]

This paper presents a time-varying model-based method for estimating earthquake-induced displacement responses of building structures using limited acceleration data. First, a time-varying model which considers the variability of stiffness by a time-variant story local stiffness reduction factor and the variability of damping by formulating the Rayleigh damping model with a time-variant mass coefficient was developed. Then, a displacement estimation algorithm was derived on the basis of the state space representation of the time-varying model and the unscented Kalman filter. The effectiveness of the proposed method is numerically verified through nonlinear responses of a ten-story building model where the hysteretic restoring force is simulated by the Bouc–Wen model. In addition, numerical results indicated that a few sensors with low noise are more desirable for the measurement strategy. Finally, the applicability to realistic seismic monitoring of buildings was investigated through a 1∶3-scale 18-story steel frame test at the E-Defense shaking table facility, which tested collapse behavior and realistic damage of high-rise steel buildings constructed in the 1990s in Japan. [ABSTRACT FROM AUTHOR]

Geofoam has the scientific name of expanded polystyrene (EPS). A block of EPS is made from particles of polystyrene through an expanding and melting process in an automatic mold machine by adding steam. The geofoam construction method employs large EPS blocks with unit weights between 12 and 30 kgforce/m3. In the 1970s, the use of EPS as a lightweight embankment in highway and earthwork developed concurrently in the United States and Norway. Most notably, in 1972, the Norwegian Road Research Laboratory placed geofoam in the approach fill of the Flom Bridge. The advantages of this construction method are that geofoam can be used not only to replace ground fill material but also to reduce the load applied to the foundation. This paper will introduce the following topics related to geofoam: the background and inspection conditions in Taiwan, United States, and Japan, the quality investigation of EPS production, and the experimental and analysis results of EPS manufacturing quality and homogenous test. This research illustrated that the quality control chart can analyze the stability of manufactured EPS. Meanwhile, the homogeneous testing method, which is put forth in this paper, can actually examine the stability of EPS manufacturing procedure. The results of this study can be used as the reference for quality control of geofoam. The issue of geofoam used for collision prevention, self-weight decreasing, and landslide resistance in geotechnical engineering will also be discussed. [ABSTRACT FROM AUTHOR]

Total quality management (TQM) has been recognized as a successful management philosophy that can be successfully implemented in the construction industry. By examining the Japanese contractors working in Egypt and comparing their managing systems to the local ones, a comparative analysis of the two contractors working in the Egyptian field is presented in this paper to illustrate how TQM can be implemented effectively in the Egyptian construction industry. Bearing in mind the location bound nature of the production process, the competitive bidding, which emphasizes cost and the absence of the quality culture of the clients, subcontractors and site operatives are some of the constraining factors for implementing the quality policy. Based on the research findings, the paper presents some features of the Japanese construction industry that could be implemented in the Egyptian field in addition to a new model for TQM implementation that appropriates the Egyptian construction industry. [ABSTRACT FROM AUTHOR]

Developments in information technology (IT) continue to have a significant impact on the architectural/engineering/construction (A/E/C) industry. However, the issue of whether A/E/C organizations are receiving adequate returns from their IT investments remains an important managerial concern. Recently, Pen˜a-Mora, Vadhavkar, Perkins, and Weber introduced a strategic IT planning framework for construction projects that includes four steps: environmental scan, internal scrutiny, IT diffusion analysis, and IT investment modeling. It analyzes the external and internal IT conditions of a project/firm, identifies the diffusion phase of IT in the project/firm, and finally evaluates the effects of IT investments on the project/firm. Although this framework was originally intended to plan future IT investments, we assume that the framework can also be used to evaluate ongoing or past IT investments in projects/firms. Following this idea, this paper presents an application of the Pen˜a-Mora et al. framework to an ongoing IT project in Kajima Corporation, one of the largest Japanese general contractors. Kajima is currently developing an IT system called LINCS (Linkage of Information for a New Construction System). This synthetic information network system has been designed to share building data among design and construction stages and streamline design/build activities. By using the framework proposed in this paper, we analyzed how LINCS is justified in terms of its strategic and operational value for Kajima and its construction projects. [ABSTRACT FROM AUTHOR]

This article documents research results from the recently completed United States-Japan Cooperative Earthquake Research Program on steel-concrete composite and hybrid structures (CHS) as of February 2004. This issue has variety of papers that fall into following three main categories: hybrid wall systems (HWS), concrete-filled tube (CFT) system, reinforced concrete steel (RCS) systems. Forum highlights some of main products of the CHS phase of the research. Some of the CFT papers out of eight are : "Seismic Behavior and Design of High Strength Square Concrete-Filled Steel Tube Beam-Columns", "Behavior of Concrete-Filled Steel Tube Beam-Columns". The first two of HWS papers are titled "Outrigger Beam-Wall Connections: I and II."

Compound flood disaster risks are increasing due to multiple river floods within a single storm event. Many studies targeted dependence structure based on multivariate extreme value theory; however, fewer studies focused on the sum of subset joint probabilities (SSJP), defined as the probability that any combination of rivers are flooded over the target area as an integral index of compound flooding risks. Modeling multivariate extremes at high dimensions faces two challenges: model complexity and sample size. In this study, as a classical asymptotic dependence model, the Hüsler–Reiss (HR) model was explored to resolve the former issue owing to its simplicity. From the multivariate HR model, any subset joint probability is explicitly obtained without numerical integration of angular measure, and dependence parameters are constructed from only pairwise parameters. The latter challenge was addressed using a large ensemble (50 members of 60-year simulation) of the database for policy decision-making for future climate change (d4PDF), which is consequently regarded as the annual maximum flow data of 3,000 years. This study analytically derived SSJP based on the HR model and tested its applicability using annual maximum flow data simulated from d4PDF for 20 rivers in Kyushu Island, Japan. The simulated SSJP based on the HR model and empirical SSJP were compared as the probability plot of the number of river basins where peak discharge exceeds the design level. As a result, under the constraint of HR that the partial correlation must range from −1 to 1, the estimated SSJP by the HR model was in agreement with the empirical SSJP. The case study presents promising results of the proposed HR model–based approach. [ABSTRACT FROM AUTHOR]

This paper, summarizing the beginnings, analysis, and future of self-anchored suspension bridges, examines the development of this unique bridge form, its uses over the past century, and its advantages and disadvantages. The Konohana Bridge in Osaka, Japan, illustrates this type and provides a case study to compare conventional suspension bridge theory with the results of a finite-element model. The final portion of the paper evaluates the potential for self-anchored suspension bridge design, and provides recommendations for design engineers. The goal here is to describe the structural behavior of self-anchored bridges in general, and of the Konohana Bridge in particular. [ABSTRACT FROM AUTHOR]

Earthquakes often occur with little to no warning and have the potential to cause enormous amounts of destruction and death. Countries with means have developed complex emergency management systems to address this constant threat. The United States and Japan were chosen for comparison because they share a similar amount of risk and have experienced large earthquakes in the last 20 years. These two countries approach this problem in drastically different ways; the United States uses a bottom-up approach, giving a large amount of freedom to local governments to address this risk. The Japanese system spreads responsibility through a directive approach, with the central government taking care of mitigation and parts of recovery, leaving the rest to be sorted out by the prefectures and local governments. This paper focuses specifically on the ways in which these two countries approach preparedness and recovery. The paper concludes with a short analysis of the strengths and weaknesses of each system, offering suggestions to strengthen future approaches. [ABSTRACT FROM AUTHOR]

The common design approach of compaction grouting for ground improvement works is oversimplified and does not account for the effects of soil properties and grouting variables. The obtained improvements therefore appear inconsistent with the predicted ones. This paper presents the results of a field test conducted at Tokyo International Airport to evaluate the effectiveness of compaction grouting under well-controlled conditions. The test consisted of 87 compaction grout piles injected in three cases of different pile diameters and spacings. The paper also discusses the effects of soil properties, replacement ratio, and injection sequence on the effectiveness that is evaluated in terms of the standard penetration test N-value and cone penetration test tip resistance, and the variation of effectiveness with depth. A new design procedure that accounts for the effects of initial soil properties is introduced. It has been found that the injection sequence has a significant effect on the grouting mechanisms and effectiveness; this effect is discussed for both high and low compressibility soils. Significant observations are also made on relatively shallow treatments, the associated ground surface heave, and the corresponding improvement. [ABSTRACT FROM AUTHOR]

In the summer of 2009, a full-scale midrise wood-frame building was tested under a series of simulated earthquakes on the world's largest shake table in Miki City, Japan. The objective of this series of tests was to validate a performance-based seismic design approach by qualitatively and quantitatively examining the building's seismic performance in terms of response kinematics and observed damage. This paper presents the results of detailed damage inspections following each test in a series of five shake table tests, and explains their qualitative synthesis to provide design method validation. The seismic test program had two phases. Phase I was the testing of a seven-story mixed-use building with the first story consisting of a steel special moment frame (SMF) and stories 2-7 made of light-frame wood. In Phase II, the SMF was heavily braced such that it effectively became an extension of the shake table and testing was conducted on only stories 2-7, making the building a six-story light-frame multifamily residential building instead of a mixed-use building. All earthquake motions were scalings of the 1994 Northridge earthquake at the Canoga Park recording station with seismic intensities ranging from peak ground accelerations of 0.22 to 0.88 g. The building performed quite well during all earthquakes with damage only to the gypsum wall board (drywall), no sill plate splitting, no nails withdrawing or pulling through the sheathing, no edge tearing of the sheathing, no visible stud splitting around tie-down rods, and reasonable floor accelerations. On the basis of damage inspection, it was concluded that it is possible to design this type of building and keep the damage to a manageable level during major earthquakes by utilizing the new design approach. [ABSTRACT FROM AUTHOR]

Transportation-disadvantaged groups have been defined in previous studies as those who are low income earners, are family dependent, have limited access to private motor vehicles and public transport services, and are obliged to spend relatively more time and money on their trips. Additionally the disabled, young, and elderly are commonly considered to be among the transportation-disadvantaged. Although generally this definition seems correct, it is not specific enough to become a universal definition that could apply to all urban contexts. This paper investigates whether perceptions of travel difficulty vary as does the definition of transportation-disadvantaged in socioculturally different urban contexts. For this investigation, the writers undertake a series of statistical analyses in a case study of Yamaga, Japan, and compare the findings with a previous case study, in which the same methodology, hypothesis, and assumptions were applied to a culturally and demographically different settlement in Aydin, Turkey. After comparing the findings observed in Aydin with the statistical analysis results in Yamaga, this paper reveals that there can be no detailed, universal definition of the transportation-disadvantaged. The writers conclude that the characteristics of the transportation-disadvantaged are not globally identical, and policies and solutions that work in one locality may not have the same results in another sociocultural context. [ABSTRACT FROM AUTHOR]

The safe disposal of radioactive nuclear waste is currently an urgent and challenging issue. Many countries, including the United States, Sweden, Switzerland, Finland, Germany, Canada, Belgium, France, and Japan, have initiated radioactive waste management programs, which now have reached various stages. Experiences and research results obtained in one country may offer valuable references for another, especially for some developing countries where nuclear power is being used and/or is under development. In this paper, we comprehensively overview the history of nuclear energy, the generation of high-level radioactive waste (HLW), and the policies and recent progress made in relation to the management of HLW in Japan. [ABSTRACT FROM AUTHOR]

Sand compaction piling is one of the commonly used countermeasures for earthquake liquefaction hazard of river dikes. This paper presents a case study of the performance of an instrumented dike in northeast Japan that was improved by sand compaction piles and subjected to the 2003 Northern Miyagi Earthquake, with the aim to better understand the effectiveness of this ground improvement method. Simulation has been carried out by means of a fully coupled numerical procedure which employs a sophisticated cyclic elastoplastic constitutive model and the updated Lagrangian algorithm. Comparisons between the field measurements and the computed responses, including the time histories of accelerations and pore-water pressures at different locations, show reasonably good agreement. Numerical simulation has also been made of the same dike but without ground improvement to identify the effects of sand compaction piles in altering the performance of the dike. The study demonstrates that the comprehensive numerical procedure is a promising tool for development of seismic performance-based design of earth structures. [ABSTRACT FROM AUTHOR]

Real-time reservoir operation models carried out under short operating horizons have no information about the seasonal changes in streamflow. The overall operation may improve provided that long-term information can be incorporated into the short-term process. This paper proposes a procedure that attempts to do such incorporation by means of stochastic and deterministic optimization. Long-term (monthly) and short-term (daily) reservoir inflow forecasts are assumed to be uncertain and reliable, respectively. The idea is to first solve a monthly operation model by an explicit stochastic programming approach and then use its information to guide the daily operation, which is solved by deterministic optimization. The monthly information will decide whether hedging should start being implemented during the daily operation in order to mitigate a potential future shortage. This stochastic-deterministic procedure is applied to a case study in Japan and the results show that it provides operating rules relatively similar to the ones obtained when perfect forecasts are used for the monthly inflows. [ABSTRACT FROM AUTHOR]

This paper reports on results of research conducted at the University of Washington to investigate the means and methods for overcoming barriers to the implementation of Web-based project management systems (WPMS), and to develop a set of best practices in both the United States and Japanese construction industries. The United States and Japanese economies are high-tech intensive and both cultures have embraced technology. However, a relatively small sector of the construction industry in each country has implemented WPMS. The question posed here is why have these drivers not resulted in the industry’s adoption of this new technology, and further, perhaps there are lessons learned from those who have successfully implemented WPMS. This research seeks to broaden our understanding of implementation barriers that are limiting the use of WPMS tools as well as means and methods of overcoming those barriers based on successful implementation in both countries. [ABSTRACT FROM AUTHOR]

Coupled building control has been shown to be an effective means of protection for flexible building structures. Numerous researchers have proposed various active, passive, and semiactive coupled building control strategies for both high-rise and low-rise buildings. Actual applications of coupled building control for low-rise buildings and high-rise buildings have been successfully implemented in Japan using passive and active control technology. Much of the research in the literature has focused on specific building pairs. To date, there have been no detailed studies of the effects of the building configuration and connector location on the overall system performance. This paper examines these effects and compares the efficacy of passive and active coupled building control for flexible adjacent buildings. [ABSTRACT FROM AUTHOR]

This study proposes an effective method of measuring the quality of a community, calculated from spatial-temporal age group distributions. For this purpose, niche indices, which are used in ecology, are employed as measurement techniques and are interpreted in terms of safety and communication. Traditional indices are examined theoretically by using spatial statistics and are shown to be essentially identical. This paper also proposes a special niche index for disaster risk evaluation. From the fact-finding studies in Kobe City, Japan, which was severely damaged by the 1995 Great Hanshin-Awaji earthquake, it is inferred that the niche index may possibly pertain to damage reduction. Further, community health in the recovery process in the Nagata Ward, Kobe City is evaluated by using the niche indices and related statistical tests. The results show that the quality of the community deteriorated after the disaster even in the area where the building recovery speed was relatively rapid. [ABSTRACT FROM AUTHOR]

This paper presents an empirical study of factors contributing to the success and failure of 24 large international construction firms originating in the United States, Europe, and Japan. The study is conducted using fundamental analysis, a methodology that is commonly applied in economics and investment practices to study the prospects of a company. Based on publicly available data, both quantitative and qualitative measures are developed and assessed collectively to derive insightful knowledge about corporate strategy and firm outlook. Preliminary conclusions drawn from this study include: (1) A universal formula for success is elusive-critical success factors can be uniquely derived from different modes of operational, financial, technological, and human-related conditions and (2) causes of failure are diverse, thus construction firms must consistently check the downside risks of all measures. Thus, debates concerning the merits of common dichotomies such as diversification versus focused differentiation appear rather hollow. These aspects of strategy are far from fixed and should instead be treated as variables. The findings suggest that an open perspective of strategy is necessary in construction organizations and provide the foundation for the development of a new strategic model for the industry. [ABSTRACT FROM AUTHOR]

As part of the U.S.-Japan Cooperative Research Program on Composite/Hybrid Structures (1992), investigations were carried out at the University of Nebraska-Lincoln and University of Illinois, to develop moment connection details and accompanying design provisions for connecting steel beams to circular concrete filled tube (CFT) columns. This paper provides an overview of the work carried out. Work at the University of Illinois consisted of evaluating the inelastic response of six possible connection details. Six large-scale connections were tested to failure using the quasi-static test method. Connections welded to the skin of the tube created large distortions of the tube wall, and were susceptible to weld, flange, or tube wall fracture. External diaphragm and continuous web details exhibited more favorable inelastic behavior, but the flexural strength of these connections began to deteriorate relatively early in the imposed deformation history. Continuing the flanges through the composite column showed adequate strength, however due to excessive slipping this connection did not dissipate significant inelastic dynamic energy. One of the details tested at the University of Illinois was passing the girder section through the CFT columns. This through beam detail provided the most effective detail to achieve the ideal rigid connection condition. Work at the University of Nebraska-Lincoln concentrated on comprehending the behavior of the through beam connection detail. The behavior of CFT columns under seismic loads was studied through testing six columns which were subjected to a constant axial load in addition to a cyclic lateral load. Failure modes for through beam connection detail were identified through testing seven, two-thirds scale connection specimens. These tests were used to comprehend the force transfer mechanisms between steel beams and CFT columns and develop design provisions that could estimate the capacity of the various elements of the through beam connection detail. [ABSTRACT FROM AUTHOR]

In the design of beam-to-column subassemblies in concrete-filled steel tubular column systems, a design formula established by the Architectural Institute of Japan (AIJ) is applied. However, in the current AIJ standard, the scope of the design formula is limited to ordinary material strengths; i.e. up to an unconfined compression strength of 36 MPa for concrete and tensile strength of 490 MPa for structural steel tubes. So, the effect of higher material strengths on subassembly behavior is studied in this investigation. The experimental results presented in this paper verified that the above-mentioned AIJ design formula is applicable up to an unconfined compression strength of 110 MPa for concrete and tensile strength of 809 MPa for structural steel tubes. An analytical model for the restoring force characteristics of the shear panel in the subassemblies was also proposed, and was found to reproduce the experimental results with good accuracy. [ABSTRACT FROM AUTHOR]

A total of three beam-to-column joints for composite structural systems consisting of reinforced concrete columns and steel (RCS) beams, which are referred to as “composite RCS systems,” were tested to investigate the structural performance and the stress transferring mechanisms as a part of the studies on “Composite and Hybrid Structures” of the U.S.–Japan cooperative earthquake research program, which started in April 1993 as a five-year research program. The joint details examined were “through-column type,” of which the joints are reinforced by cover plates and horizontal stiffeners without beam flanges. This paper indicates that the use of thicker cover plates and extended face bearing plates are effective to enhance the structural performance of the joints. Stress transferring mechanisms in the joints are also discussed using three macromodels. [ABSTRACT FROM AUTHOR]

Seismic design guidelines for composite reinforced concrete and steel (RCS) buildings consisting of reinforced concrete columns and structural steel beams were proposed in Japan as a practical outcome of the U.S.–Japan Cooperative Earthquake Research Program on Composite and Hybrid Structures. A design method satisfying the most prevalent seismic provisions used in Japan, which are based on the working stress design method, is described. At the same time, an alternative method, which is suitable for use in the context of the capacity spectrum method, is also briefly introduced. This paper outlines the design guidelines, giving priority to an explanation of the design method for the working stress seismic provisions. In this method, the weak beam–strong column mechanism is used as the design basis for buildings under severe earthquake. Therefore, moment magnification factors for both columns and joint panels are provided to secure the mechanism. Design equations for the ultimate shear strength of joint panels and associated hysteresis models are also included in the guidelines, and can be applied to a total of twelve details of RCS beam–column joints, including both the through beam and the through column types. [ABSTRACT FROM AUTHOR]

The 1995 Hyogo-ken Nanbu (Kobe), Japan earthquake provided the world’s first experience with earthquake damage to new long-span bridges designed to 1990s seismic standards. This paper reviews damage and describes techniques used to repair three major steel bridges along the Wangan route (Bayshore route) in Kobe—the 885 m Higashi-Kobe Bridge, the 217 m Rokko Island Bridge, and the 252 m Nishinomiya Port Bridge. These bridges, in service for less than three years, were essential components in the highway transportation system in the Kobe region. Extremely large ground motions, and failure of bearings, connections, and seismic restrainers were principal contributors to the damage sustained by these bridges. Repairs utilized heavy-lift floating cranes (up to 4,100 ton capacity) and various jacks to stabilize the structures and to realign spans. In one case, reconstruction of a collapsed span was required, with lifting weight a prime concern. Significant constraints on the repair included confined working space and requirements for maintaining maritime navigational clearances. The closure times for the repair of the bridges ranged from three to nine months. [ABSTRACT FROM AUTHOR]

Full-scale data on damping of buildings in Japan have been collected by the Damping Evaluation Committee of the Architectural Institute of Japan. Reliable data on 137 steel-framed buildings, 25 reinforced concrete (RC) buildings, 43 steel-framed reinforced concrete (SRC) buildings have been compiled in a database. Most of these data have been evaluated from vibration tests in a small amplitude region. This paper describes damping ratio characteristics of steel-framed buildings and RC/SRC buildings based on analyses of the database, including effects of several building factors. It is shown that the higher the building, the smaller the first-mode damping ratio. Furthermore, the damping ratios seem to be affected by building use: Those of hotels and apartments are generally larger than those of other buildings. However, damping ratios are more widely scattered than natural periods, because they are also affected by vibration amplitude, foundation type, and so on. Frequency and amplitude dependencies of damping ratios are also examined, and predictors of damping ratios with their dependencies are proposed. [ABSTRACT FROM AUTHOR]

It is crucial for the Japanese government to establish a new energy mix plan since the previous plan was subject to review after the Fukushima nuclear accident in March 2011. The Japanese government proposed a new energy mix option in June 2015. However, the high degree of uncertainty will impair the robustness of energy mix options decided based on predictions. This paper uses robust decision making (RDM) to take uncertainty into account and determine robust energy mix options. An hourly electricity dispatch and power plant renewal simulation covering 2016–2035 in Japan is conducted to analyze the economic and environmental impacts of several energy mix options. The results show that the options with greater use of coal-fired and wind power plants have robustness against future uncertainties and that the current government plan is inefficient. [ABSTRACT FROM AUTHOR]

This paper presents a geographic information-based mixed integer linear programming model for a district heating system design. The model minimizes the annualized investment and operation costs of the system, with the key results showing the optimal distribution network structure and optimal capacity and dispatch of heat plants. A network topology of nodes and edges, providing accurate geographic representation of the district, is generated using a geographic information system and acts as a constraint. A case study is conducted for a district in Hirosaki city, located in the northernmost prefecture of mainland Japan. The results demonstrate the considerable economic benefits of integrating locally available woodchips in heat-only boilers instead of using city gas due to lower fuel costs. Low temperature operation reduces the fuel costs due to less network heat loss compared to medium temperature operation, but it is overcome by the cost of the larger pipe size and the pumping power. Implementation of the district heating system to the case area encourages sustainable development through economic favorability, decreased primary energy consumption, and considerable CO2 emissions reduction, compared to the current heat supply structure. [ABSTRACT FROM AUTHOR]

Distributed energy systems such as solar power photovoltaics (PV) and cogeneration systems (CGS) are expected to play a main role in future energy systems. However, consumers employ these distributed energy systems based on individual decisions rather than topdown installation planning, so even if the expansion of PVand other renewable energy sources is a national energy policy, it remains uncertain how and when PV installation targets will be realized. Furthermore, when consumers extensively deploy distributed energy systems, the power-expansion planning of utilities will be affected by changes in daily load patterns. In this paper, the authors develop a two-stage model focusing on interactions between the energy system adoption behavior of customers and power-expansion planning of a utility. In the first stage, the authors disaggregate Japan’s Kanto region into 38 areas and then develop an optimum energy system model including PVand CGS for consumers. In the second stage, the demand for electric power from the utility is transferred to the power-expansion planning model of the Tokyo Electric Power Company. The authors observe how well the results for PV penetration agree with the cost and the market projection scenarios given by governmental plans. The effects of subsidy scenarios for PVare also evaluated. The authors find that PV penetration will not meet installation targets unless additional PV promotion policies are implemented. The power-expansion model in Stage 2 shows how consumer behavior affects long-term expansion. These findings suggest the need for an integrated energy policy promoting a low-carbon society [ABSTRACT FROM AUTHOR]

Frequent catastrophic earthquakes have highlighted the significance of postearthquake recovery and reconstruction (PERR) planning, a dynamic and inclusive process which encourages the building of more resilient communities. This paper aims to provide some meaningful lessons for quake-prone countries through a review, comparison, and discussion of PERR planning success and failure factors in the 1994 Northridge earthquake in the United States, the 1995 Kobe earthquake in Japan, the 2003 Bam earthquake in Iran, and the 2008 Wenchuan earthquake in China. The authors then provide some guidance for PERR planning in key areas such as formulating predisaster planning, enabling participatory planning, capacity building for public involvement, schedule control, process coordination, developing catastrophe insurance, protecting vulnerable groups, and assessing plan quality. Further in-depth studies could be done to conduct broader crossnational comparisons on some important specific aspects, such as predisaster planning, participatory planning, and plan implementation. [ABSTRACT FROM AUTHOR]

The stability of slopes subjected to vertical embedded strip footing loads under static and seismic conditions was investigated. The pseudostatic method was considered to represent an earthquake load. Two-dimensional lower-bound finite-element limit analysis (LB-FELA) and the strength reduction method (SRM) were employed to investigate the stability and failure mechanisms of the slopes subjected to the footing loads. It was found that the factor of safety (FOS) started to decrease rapidly after a certain load (defined as a threshold load). The critical location of the footing on the slope (where the FOS was at a minimum) was examined. In addition, a series of numerical analyses were carried out to check the effect of edge distance on slope stability. Changes in the FOS were evaluated for a particular footing edge distance for varying slope angles. The effects of variation in the shear strength parameters and the location of the water table on the slope stability under footing loads were also examined. It was found that the effect of loading intensity on the FOS was significant for gentle slopes, with this effect decreasing for steeper slopes. The influence of footing width on the FOS, for a given slope angle and loading intensity, was also insignificant. The footing near the slip surface at the top of the slope was the most critical location. The effect of the water table on the FOS diminished as the loading intensity on the footing increased. To demonstrate the practical application of this study, we also examined the slope failure that occurred during the 2011 Tohoku, Japan, earthquake. [ABSTRACT FROM AUTHOR]

Yokohama Bay Bridge, with a total span length of 860 m, is the second longest span cable-stayed bridge in East Japan, and one of the most densely instrumented bridges in Japan. On March 11, 2011, the Great East Japan (Tohoku) Earthquake hit northeastern Japan with magnitude of 9.0, notably the largest earthquake in Japan's modern history. Intensity of the maximum scale 7 of Japan Meteorogical Agency's seismic intensity was recorded on the bridge site. This paper describes seismic response analyses of the bridge, system identification, performance evaluation of link-bearing connections (a seismic isolation system), and postearthquake field observation. Response analyses show that transverse vibration dominated the response of girder and tower, with a maximum girder displacement of 62 cm. The large transverse vibrations induced pounding between tower and girder on the tower-girder connections as shown by the periodic impulses on acceleration records. Meanwhile, longitudinal accelerations indicate that the link-bearing connections functioned properly during the earthquake. System identification reveals nonlinearity of the response as evidenced by variations in natural frequencies and mode shapes during large excitation. Despite these conditions, the bridge did not suffer any structural damages, since the ground motions experienced during the earthquake were less than the design and seismic retrofit ground motions. [ABSTRACT FROM AUTHOR]

Cold-formed thin-walled steel residential building systems, because of their good environment protection, seismic performance, and high construction efficiency, have been widely used in the United States, Canada, Japan, and Australia, and recently, they also have had good application in China. Although a variety of studies have been carried out all over the world in the last 20 years, there is no related design code for this kind of building in China. For this reason, a series of research has been conducted in China recently, considering the consistency of standard systems in structural design in China and the newest development in the world. The contents of the paper can be divided into two parts. First, the major research works conducted by the authors over the last 5 years and the main findings are reviewed and summarized. Second, based on a Chinese professional standard, a brief summary of the design methods for cold-formed thin-walled steel framing residential buildings developed by the authors and other researchers in China is introduced. [ABSTRACT FROM AUTHOR]

Sustainable coastal zone management strategies are imperative to avoid extreme social upheaval in both developing and developed countries. There is an increasing concern that the current management practices for many coastal regions are unsustainable under changing environmental and climate conditions. Sea level rise is of particular concern in coastal regions, and few countries have planned to deal with the exacerbation of environmental decline in the face of sea level rise. It is therefore necessary to assess socioeconomic and environmental impacts of sea level rises to better understand the vulnerability of the coastal zones, as part of devising adaptive and integrated management principles. This paper presents a systematic approach in which relevant stakeholders in Australia and Japan were actively engaged in identifying and prioritizing issues relating to the impacts of inundation and reduced water quality associated with flooding. The extent to which these issues are likely to be affected by flooding is quantified using synthetic response functions, and the key issues of concern for flood impacts for coastal areas in Australia and Japan are compared. Synthetic response functions as developed in this study can be used to quantify the likely impacts of flood hazards of various magnitudes. [ABSTRACT FROM AUTHOR]

High-speed rail in infrastructure construction has become a priority worldwide, and vast investments have been made; therefore, it has become increasingly necessary to appropriately assess regional economic impact, and more importantly, to deliberate policy to improve regional industrial development. This paper looks at the impacts of Shinkansen lines on industrial locations in Japan. Unlike previous research, this study investigates both socioeconomic factors and physical determinants through an empirical industrial location model and multivariable stepwise regressions. The results indicate that during the period of 1990-2000, the dominant driving force of industrial location has changed from industrial transaction interdependence to population consumption demand. The elasticity of accessibility to the Shinkansen network has also shown an increasing trend from 1990 to 2000. Further expansion of Shinkansen lines would encourage the development of several industries, such as real estate, commerce, and services, and would thus contribute to forming the regional economic structure. [ABSTRACT FROM AUTHOR]

There is widespread awareness in seismic-prone countries about the necessity to upgrade the seismic performance of old buildings and wooden houses for disaster mitigation; however, upgrading occurs at a very slow pace. At present, Japan has approximately 11 million nonconforming old wooden houses, but most of them remain without upgrade because of the large expenditure that would be incurred by both house owners and the local government. An owner would need to spend approximately US$11,000 on average to upgrade his/her house such that it satisfies the current design requirements. In Aichi prefecture alone, upgrading would cost approximately US$10 billion in total, which is approximately 40% of the annual budget. This study, therefore, investigates alternative strategies for upgrading existing nonconforming wooden houses more efficiently and cost-effectively. The seismic risks of wooden houses as a whole in Aichi prefecture are estimated, and then the effective target level for upgrading is discussed from the viewpoint of both economic loss and the number of fatalities. It is shown here that it is worthwhile from the viewpoint of life safety to consider a target upgrading level that is lower than the current design requirements. Although the analytical models discussed in this paper might be specific to Japan, the framework of the risk assessment is universal and the conclusions drawn from this analysis are applicable to other seismic-prone regions and countries. [ABSTRACT FROM AUTHOR]

This paper presents the improved performance of a regional climate model for the Japan region when a fully coupled boundary layer model and an areally averaged land-surface flow model are employed. It also describes results from the application of the regional climate model to the region for climate-change prediction. An integrated regional-scale hydrological-atmospheric model (IRSHAM) was developed for the Japan region that consisted of a 60-km resolution large-domain model nesting a 20-km resolution small-domain model. The small-domain model was equipped with two-way interaction between the areally averaged land-surface parameterization and the first layer of the atmospheric model. A historical period was then simulated by IRSHAM for local precipitation and other hydrological processes. Simulation results showed a significant improvement in the monsoon-affected regional distribution of monthly precipitation in the Japan region. The simulation results correlated with their counterparts observed at the Tsukuba ground station, showing that IRSHAM performed well in predicting daily meteorological changes. IRSHAM performed another run to simulate local-scale effects of the climate change caused by a doubling of the CO2 concentration based on Meteorological Research Institute general circulation model (GCM) I data. IRSHAM successfully downscaled GCM-I outputs to project local-scale changes in temperature and precipitation over the Japan region. [ABSTRACT FROM AUTHOR]

Planning and preparedness is essential for any resilient infrastructure system. Modeling and simulation give engineers and planners a better understanding of the system and help them make better decisions. The objective of this study is to demonstrate an improved model for the disaster restoration process by using a discrete event simulation approach. The study also aims to help improve the postearthquake restoration process by simulating restoration curves. In this paper, colored Petri nets are used to model the system and to simulate its behavior. The resource allocation after a rare event such as an earthquake differs from the resource allocation of other projects and processes in that the time to do the repair and recovery is not known before the event, and the priorities might change for different operational plans and strategies. The trunk network of the Tokyo water distribution system was used as an example to present the scenario and to model the restoration process. The timed simulation allowed visualizing the restoration progress, which is usually depicted as a restoration curve. The results for the restoration time for multiple simulations are presented. [ABSTRACT FROM AUTHOR]

Advanced traveler information systems (ATISs) are continuously becoming key intelligent transportation system for disseminating valuable traveler information such as traffic, incident, and transit information. Developed countries such as the United States, Canada, Japan, U.K., Australia, and Germany have adopted ATIS expeditiously in comparison to developing countries that face considerable financial and framework constraints. Moreover, local traffic, roadway, signalization, demographic, topological, and social conditions in developing countries are quite different from those in developed countries. In this paper, a comprehensive framework comprising of system architecture, development methodology, and salient features of a developed ATIS for metropolitan cities in developing countries has been discussed. Development of proposed system is based on integration of two well-known information technologies, viz., geographic information systems and World Wide Web. Combination of these technologies can be used to develop an integrated ATIS that targets different types of travelers such as private vehicle owners, transit users, and casual outside visitors. [ABSTRACT FROM AUTHOR]

This paper summarizes the seismic response of five large-scale retaining walls having a geocell facing. The walls were 2.8 m high and the backfill and foundation soil were a fine sand compacted to 90% standard Proctor density (relative density of 55%). The first two walls were of the same geometry, with a tapered facing made of geocells each of height 20 cm, one infilled with gravel and the other with sand. In Wall 3, a facing of depth 60 cm was constructed while the backfill sand was reinforced with a polyester geogrid. Wall 4 was similar to Wall 3 except that the backfill was reinforced with several geocell layers. Wall 5 had thin geocell layers of 5 cm height as reinforcements in order to improve the performance compared with Wall 4. The walls were subjected to the scaled horizontal and vertical motions as recorded during the 1995 Kobe earthquake, 4.5 m/s2(450 gal) and 9.0 m/s2(900 gal) maximum horizontal accelerations in the first and second excitations, respectively. In an attempt to induce failure, and therefore, to investigate the failure mechanism, Walls 3–5 were subjected to a third shaking in which the horizontal accelerations were scaled to 12.0 m/s2(1,200 gal). The walls were fully instrumented with accelerometers, laser displacement transducers, force transducers, and strain gauges. All five walls performed satisfactorily under the simulated earthquake motions. An improved wall performance was seen with the geocells acting as reinforcement layers. The study showed that geocells can be used successfully to form gravity walls as well as reinforcement layers even when subjected to a very high seismic load beyond that of the Kobe earthquake. [ABSTRACT FROM AUTHOR]

This paper presents a sensitivity analysis of the effects of different fault plane parameters on earthquake generated tsunamis in the far field. The parameters studied include the location of epicenter, rake angle, dip angle, strike angle, fault plane dimensions, slip displacement, and focal depth. The study was carried out by applying the verified Cornell COMCOT tsunami model to simulate distant tsunamis generated by earthquakes in three different seismic regions, namely, Japan, Aleutian Islands, and Chile in the Pacific Basin. In this study, each fault plane parameter was varied and its effect on the tsunami wave height at a distant location (Hawaii offshore waters as a case study) was examined. Our results showed that under the same earthquake magnitude, in general, variations within a reasonable range of uncertainty in rake and dip angles, epicenter location, and focal depth do not affect the resulting tsunamis significantly while a variation in the fault dimensions, strike angle, and slip displacement can cause a large change in the wave heights in the far field. The study revealed that the sensitivity of the far field wave height to certain earthquake parameters including the fault plane dimensions, slip displacement, and the strike angle does not always decrease as the distance between the earthquake and the far field increases. These results indicate the importance of accurate earthquake information for accurate tsunami predictions and that even for wave heights in a far field thousands of miles away, the earthquake may not be treated as a simple point source described by its epicenter location and magnitude alone. [ABSTRACT FROM AUTHOR]

This paper describes the influence of water outside a bay on water quality within the bay for a typical enclosed bay with a sill at its mouth. The influence of water outside Ohfunato Bay, Japan was expressed in a one-dimensional vertical dissolved oxygen (DO) model as the rate of seawater exchange caused by tides and the density difference between water inside and outside the bay. A nonhydrostatic, three-dimensional model was used to confirm the occurrence of density intrusions. A one-dimensional vertical DO model was used to examine long-term changes in DO concentrations in the bottom layer of the bay. Results indicated that seawater exchange caused by density differences had a significant effect on the formation and disappearance of anoxic water in the bay’s bottom layer. [ABSTRACT FROM AUTHOR]

This paper presents the current state of the art of nonlinear analysis of steel-concrete composite structures. The focus is on frame elements, which are computationally faster than continuum finite element models. First, section models are presented, with a review of resultant and fiber models and a discussion of possible practical applications. The presentation of frame elements follows. Models with lumped and distributed inelasticity, as well as models with perfect and partial connections are covered. Rigid and partially restrained joints are then reviewed and discussed at length. A discussion of the analysis of structural walls completes the presentation of the models. Modeling applications to the analysis of composite frames are also presented. This state-of-the-art review focuses on developments that have stemmed from the recently completed National Science Foundation sponsored U.S.-Japan program on composite and hybrid structures. [ABSTRACT FROM AUTHOR]

A 5 year research on concrete-filled steel tubular (CFT) column system was carried out as a part of the fifth phase of the U.S.–Japan Cooperative Earthquake Research Program, and the tests of centrally loaded short columns were finished. The objectives of these tests were to clarify the synergistic interaction between steel tube and filled concrete, and to derive methods to characterize the load–deformation relationship of CFT columns. A total of 114 specimens was fabricated and tested in the experimental phase of investigations on centrally loaded hollow and CFT short columns. Parameters for the tests are as follows: (1) tube shape, (2) tube tensile strength, (3) tube diameter-to-thickness ratio, and (4) concrete strength. In determining the range of parameters, the emphasis was placed on obtaining a wide range of test data for establishing a generally applicable design method of CFT column systems. Design formulas to estimate the ultimate axial compressive load capacities are proposed for CFT columns with both circular and square sections based on tests results described in this paper. [ABSTRACT FROM AUTHOR]