Journal of Asian Architecture and Building Engineering
Online ISSN : 1347-2852
Print ISSN : 1346-7581
Current issue
Displaying 1-26 of 26 articles from this issue
Architectural History and Theory
  • Seunghan Paek
    2018 Volume 17 Issue 3 Pages 385-392
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This article explores how philosopher Gilles Deleuze′s theory of the fold is extended to architectural design, and how such an extension prompts ′event′ in both the conceptual and realistic senses. In doing so, this article conducts two case studies: 1) the Rebstockpark Master Plan (1990-1991), and 2) The Aronoff Center for Design and Art (1988-1996). These two projects have similarities in that both were influenced by a Deleuzian theory of the fold in one way or another, which highlights that the world we live in is not so much homogeneous and fixed but rather multiple and in a perpetual process of becoming. While one can detect the influence of Deleuze′s theory in these Eisenman projects, it becomes more prominent in the latter case—the Aronoff—given that it is a built project in which the architect′s design conception provokes a multitude of events through the entanglement of various individuals′ fabrics of everyday life. By looking at both the conception of the fold proposed by Eisenman, and my habitual encountering with his built project where his theory is actively implemented, I claim that the Deleuzian event is not just a spectacular kind prompted by Eisenman himself, but unfolds in more subtle ways.
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  • Yoonchun Jung
    2018 Volume 17 Issue 3 Pages 393-400
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
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    This paper focuses on determining the architectural intention of Tadashi Sekino, portrayed in his writings on Japanese and Korean architecture, entitled ″Kikou oyobi chishitu yori mi taru nissen no kenchiku″ [Japanese-Joseon architecture seen from the perspective of climate and geological features] published in Chosen to Kenchiku in 1924; in his journal paper, Sekino claims that the architectural differences between Japan and Korea are related to the geological, climatic, and customary differences between the two countries. However, it is very important to acknowledge that Sekino′s perspective later radically changed from his previous position where he had mainly argued stylistic similarities between Japanese and Korean architecture, beginning with his first publication on Korean architecture in 1904. In this context, this paper argues that Sekino′s architectural writings of 1924 were informed by contemporary Japanese political propagandas that expressed Japan′s attitude towards the West. Especially, for the purpose of dealing with the world politics of the time, Japanese architects attempted to construct a historical narrative to highlight the architectural uniqueness of Japan over its Asian and Western neighbors.
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  • Seunghan Paek, Dai Whan An
    2018 Volume 17 Issue 3 Pages 401-408
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This article explores how idealized architectural plans are negotiated in relation to the practical concerns and socio-cultural conditions of modern and contemporary Korea. As a case study, it focuses on analyzing the masterplans of Yonsei University, one of the key universities that illustrate the architectural modernity of Korea, as well as reflecting the continual interactions between different agents of power within and outside the country. Particular attention is given to the evolution of the university′s masterplans at four different points in time: the plans proposed in 1917, 1925, 1957, and 1970 respectively, all of which are compared to the 2016 map. The 1917 plan is a product made by an American architect—Henry K. Murphy—who proposed a design without visiting the site. Such a process lacking tactile engagement resulted in generating an overly western-style and also an ′ideal′ plan that does not adequately respond to actual site conditions. While the 1925 and 1957 plans are updated versions that are based on Murphy′s site visits, they still seem idealized to a great degree. It is rather the last two maps—1970 and 2016 plans—where one can detect how they manifest themselves for the changing conditions of modern and contemporary Korea; a number of those working at the university participated in the design process, which focused on generating more realistic strategies in response to South Korea′s ′compressed modernity′. Our in-depth visual analysis of the Yonsei masterplans shows how idealized plans are negotiated and reworked, thereby reflecting realistic demands for university life in material ways.
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Architectural/Urban Planning and Design
  • Huiqin Hu, Zhiqiu Xu, Guanyu Che
    2018 Volume 17 Issue 3 Pages 409-416
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    With community elderly care facilities as the breakthrough point, this paper is based on the field of old community research and model analysis, taking the related residence conversion methods as a philosophical basis and reference, and tentatively proposes optimal residence conversion methods and key points of design in aging old communities.
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  • Linlin Dai, Lun Liu, Jingjing Cui
    2018 Volume 17 Issue 3 Pages 417-424
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    A framework is established for evaluating the adaptability of rural households to tourism disturbance in the suburbs of a metropolis, based on the theory of the social-ecological system with tourism as the system disturbance. Two traditional villages in Beijing suburbs are selected as study cases and compared in terms of the development stage of tourism and the phases and approaches of adaption by rural households to tourism disturbance. Stepwise regression and grey relational analysis are applied to investigate the factors influencing the functionality and stability of the rural social-ecological system.
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  • Masahito Kamimura, Juichi Yamazaki
    2018 Volume 17 Issue 3 Pages 425-432
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This study clarifies three things about the housing environment that should be considered when planning future community vitalizations through collaborations among people on remote island regions with different origins and immigration motives. First, it identifies the factors that influenced the residential composition of Shiraho. Second, it classifies residents by origin. Third, it identifies the characteristics of residential locations according to the residents′ origins and immigration timing. The results show that the residential composition of Shiraho changed in four stages. Regarding the spatial distribution of households in the residential areas of Shiraho, similar Shuriners and similar Taramanians resided in respective clusters, which were spatially separate from Shirahonians. Recent immigration of outsiders changed the distribution of the old residential area, but in some cases they came to reside in newly opened areas that other residents avoided for various reasons.
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  • Huei-Chen Lee, Chih-Ming Shih
    2018 Volume 17 Issue 3 Pages 433-440
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The implementation of various preservation processes in two historical districts, the Sanxia Minquan District and the Daxi Heping District, yielded different results. In Daxi, old industries and neighborhood networks still exist, whereas in Sanxia, they have disappeared behind the formation of a new commercial community primarily focused on historical tourism. These results were influenced by the promotion and long-term implementation of government policies, the actions of architecture and urban planning professionals, and the formation of historical preservation organizations. Crucial factors for maintaining local characteristics when preserving historical districts are constant governmental investment in historical preservation and district revitalization programs, professional facilitation and assistance in the operation of community organizations, and locally operated community organizations that can propose and execute district preservation and revitalization projects.
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  • Tsuyoshi Seike, Yumi Shoji, Yuki Takemura, Yusuke Kunie, Rizalito M. M ...
    2018 Volume 17 Issue 3 Pages 441-448
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    In Manila, the Philippines, resettlement projects have been implemented to relocate informal settler families from slums and disaster-prone metro areas. At resettlement sites, housing units are often provided to beneficiaries, who then extend and renovate them. Such extensions and renovations of housing, and the processes involved, are considered to have a significant impact on living environments and local communities; however, these impacts are not yet fully understood. Thus, this paper investigates the following elements at St. Martha Estate, one of the resettlement sites: A) the condition of housing that has undergone extension and renovation, B) the construction systems used for these extensions and renovations, and C) the attributes of the residents. Subsequently, correlations among A, B, and C were analyzed to gain knowledge that can improve the living environment. First, we examined A by conducting a photographic survey of the houses′ exteriors and interiors. Then, B and C were examined through interviews with the residents. Through analysis of correlations between A, B, and C, it was found that the characteristics of the builders of the extensions and renovations were related to the construction skill and the economic conditions of the residents, which in turn affected the condition of the extensions.
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  • Yun-Cheol Nam
    2018 Volume 17 Issue 3 Pages 449-456
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This research presents the process of developing the ′Sanneoul′ Eco-village, located in South Korea, and describes community life in the village. Sanneoul village was created to welcome urban dwellers who choose to return to rural life and to prevent the exodus of the population in rural areas. The village features eco-friendly architecture and utility systems within which the residents live as a community. Nearly fifty community meetings were held by the residents of the village from the beginning to the end of the construction process. They received public funds to cover most of the basic costs for the village construction, and the households moving in as residents covered only the costs of the property, land, and buildings. This advantage is one of the important factors that attract city dwellers to return to rural areas. The ecological systems installed within the village include rainwater recycling, grass blocks, rooftop gardens, and an ecological sewage disposal plant. The ecological elements of the architecture are the sunlight and solar heat system, pellet boiler, fireplace, and ′ondol′ floor heating. The residents actively participate in recycling garbage, food waste, and feces. The village residents are contented with the eco-friendly aspects of the village and have been active participants of the system.
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  • Hyeseung Song, Hye-Young Cheong, Byunghye Jun, Myeong-Hun Lee
    2018 Volume 17 Issue 3 Pages 457-464
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    Local communities face conflict among various social values and experience many problems in the physical and social realms. Community resilience provides support to ensure that the local community continues to respond to a variety of simultaneous problems. In this study, we analyzed community resilience by observing the case of Jangsu Village in Seoul, Korea. Jangsu Village has been continuously developing its unique residential area for about ten years to enhance the self-sustenance of the region and to cope with local crises.
    From the perspectives of community resilience, we examined how to improve upon the community resilience in Jangsu Village. This study derives the resilience factors required for each stage of development. In the initial stage of activities, various civilian experts should lead projects and local activities to secure abilities according to three characteristics: reflective, resourceful, and inclusive. The resilience characteristics required for the development phase are flexibility and integration. When entering the mature phase, local actors can further expand their activities, and related projects may be carried out with stability. The resilience characteristics necessary for this stage are robust and redundant to prepare for future risks.
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Building Structures and Materials
  • Hyeong-Gook Kim, Kil-Hee Kim
    2018 Volume 17 Issue 3 Pages 465-472
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This paper proposes a simple analysis method to estimate the additional damping ratio required to achieve a target seismic performance level. The proposed method employs the Newmark and Hall′s design response spectrum and the simple version of the N2 method. With the help of combining the characteristic of the two methods, it is possible to approximately estimate additional damping ratios required to achieve target elastic or inelastic seismic responses of a building structure without iteration. To examine the validity and effective range of the proposed method, time history response analysis is conducted, and the results are compared with those of a numerical analysis in which the post-yield stiffness ratio is considered. The analytical results show that the post-yield stiffness ratio and the yield displacement are important factors that affect the validity of the proposed analysis method; it is also found that the proposed simple analysis procedure may be quite efficient in evaluating the performance point and the damping requirements for seismic response reduction of building structures.
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  • Taewan Kim, Yurim Chu
    2018 Volume 17 Issue 3 Pages 473-480
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    Korean seismic design practice for ordinary reinforced concrete wall-frame buildings is similar to but a little different from the equivalent lateral force design procedure per ASCE 7. The specific feature of the Korean practice is not to separate the walls and frames into an independent structural system, but to analyze and design them simultaneously, while they are separated and then analyzed and designed individually if following ASCE 7. Therefore, the Korean practice is assessed by using the performance evaluation procedure presented in FEMA P695. The results showed that the Korean design practice is not always applicable to all RC wall-frame buildings with ordinary shear walls. This negative result is due to a significant reduction in the design moment of the walls. The reduced moment makes the thickness and vertical reinforcement of walls designed by the Korean practice significantly smaller than those by ASCE 7, while the frame member sizes are similar. If structural engineers want to keep using the same design practice, appropriate methods to offset the significant reduction in the design moment should be incorporated such as reducing the R-factor or limiting reduction in the design moment.
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  • Yutaka Matsumoto, Masaru Shimazu, Miki Hayashi, Koji Azuma, Kazuo Kuri ...
    2018 Volume 17 Issue 3 Pages 481-485
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    In this paper, the shear strength of circular reinforced concrete (RC) columns was obtained using numerical models based on a modified compression field theory that enabled the sectional analysis of the beams. By comparing the computational results with previous experimental results, we were able to assess the suitability of this numerical model for estimating the shear strength of circular RC columns. Additionally, the validity range of the shear strengths was evaluated by substituting rectangular column sections for circular column sections. The relationship between the shear strength of the circular RC columns and the shear span-depth ratio were also discussed. On a final note, we examined by calculating the shear strength of the numerical models by using equations to estimate the concrete strength of confined concrete.
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  • Qiong Xing, Jiang Qian
    2018 Volume 17 Issue 3 Pages 487-494
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The group influence of three high-rise buildings was modelled by considering the buildings as three circular cylinders. The typical wind tunnel tests of flow around one circular cylinder at a Reynolds number of 3900 and around three circular cylinders in equilateral-triangular arrangements were numerically simulated. The numerical results were in good agreement with wind tunnel test results, demonstrating the feasibility of the numerical model. In the subsequent studies, a two-dimensional model of three circular cylinders in equilateral-triangular arrangements was used as a simplified model for the simulation of flow around the three high-rise buildings. The result showed that at a small spacing ratio, the wake behind two parallel structures downstream of the three was asymmetrical; this result was explained by the phenomenon of bistable flow around practical structures. With an increase in spacing ratios, the asymmetrical wakes of the two parallel structures disappeared, and the range of the critical spacing ratio of bistable flow was identified. The changing tendency of the drag coefficients and the lift coefficients of two parallel structures downstream was not a simple decrease, and was more complicated than that of two side-by-side cylinders. At small spacing ratios, the bistable flow generated an across-wind force.
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  • Takaya Nakamura, Manabu Yoshimura
    2018 Volume 17 Issue 3 Pages 495-502
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    Buildings with brittle columns are in danger of gravity load collapse and may be hazardous in the event of future earthquakes. To plan for building evacuation, the time required for such buildings to collapse must be known. This study thus uses dynamic analysis to examine the collapse time of reinforced-concrete (RC) buildings designed according to old Japanese codes. Model lateral load vs interstory drift relations are represented based on previous collapse tests of brittle columns. The results reveal that (1) in most cases, the time between shear failure and collapse is very short for individuals to safely evacuate a building, and (2) the collapse time can be long for earthquakes with long durations.
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  • Sejun Jang
    2018 Volume 17 Issue 3 Pages 503-509
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This paper proposes a construction method for efficient application of multi-trade prefabrication (MTP). The currently most advanced prefabrication method, MTP was recently introduced in North America and Europe. However, there have been few reports and studies of MTP in Asia. This paper discusses MTP construction method application in a workshop and presents solutions to identified problems. MTP pilot test 1 was performed using combinations of conventional chain block and scissor lift. Productivity analysis indicated that on-site MTP construction increased an extra labor input which was 19.6% compared to the total labor input of the conventional method. Pilot test 2 used manual material lifts for on-site MTP construction. Labor input per MTP module was reduced to 75.8% of that required for pilot test 1, but the manual lifts extended overall construction time. Pilot test 3 used a proposed optimized stacker based lifting device. Labor input for on-site MTP construction was reduced to 47.0% of that for pilot test 1. These results will be the basis for development of best practices for future MTP construction and provide better understanding as well as directions for improving MTP construction.
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  • Tao Wang
    2018 Volume 17 Issue 3 Pages 511-518
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
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    This paper presents a theoretical method and FEM to study the overall buckling of an H-section steel member with narrow flanges. The theoretical study aims to elaborate the significant parameters involved. Based on the theoretical analysis, a parametric study is performed to identify the adequate coefficients for the design of an efficient and general evaluation technique to form the equation. As a result, the approximate closed-form equations are successfully proposed for the elastic critical moment of the H-section beam. Besides, the numerical analysis by FEM is performed to investigate the ultimate load, and the design equation for the ultimate load of an H-section column under combined compression and bending is recommended.
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  • Kenneth Bull, Juan Jose Castro, Kozo Nakada
    2018 Volume 17 Issue 3 Pages 519-524
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The current practice in Japan for most driven pre-stressed high strength concrete (PHC) piling sites utilizes an ″energy formula″ approach involving the ″set-penetration test.″ In its current state, driven PHC piles in the Japanese construction industry are at increased risk of being damaged due to inferior driveability evaluation procedures leading to an increased probability of damaged piles remaining undetected after installation. This study presents two case studies in Okinawa, Japan which utilized dynamic analysis as the primary piling quality acceptance criteria and compares results to the energy formula approach which is more common to Japanese construction sites. Based on the observations of these two case studies, the applicability of dynamic testing, particularly the high-strain dynamic test, the low-strain integrity test, and wave equation analyses is analyzed. In conclusion, a case is presented that Japan′s over reliance on an energy formula approach should be augmented by additional QC procedures. A combination of wave equation analysis, dynamic testing and simple visual inspection of post-driven PHC pile conditions is recommended to better protect the integrity of driven PHC piles throughout Japan.
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  • Zhanguang Wang, Yang Wang, Changren Pan, Jie Li
    2018 Volume 17 Issue 3 Pages 525-531
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    Torsion tests of hollow steel tubes and aluminum foam-filled steel tubes after fire have been carried out. The influencing factors, on the static torsional behavior of aluminum foam-filled steel tubes after fire were also investigated, including the porosity rate of aluminum foam and steel rate. The research results suggested that aluminum foam filled in tube had systolic collapse after high temperature. The oxide layer of the steel tubes had an exfoliation phenomenon. The uniaxial torsional curves of aluminum foam-filled steel tubes after fire have a longer plastic collapse region, and have no obvious hardening stage. The ultimate torsional bearing capacity of the steel tubes filled with foam aluminum after fire is half of that before fire. Compared with hollow steel tubes, the deformation and ultimate torsional strength of steel tubes filled with foam aluminum after fire is improved.
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  • Xuansheng Cheng, Liang Ma, Aijun Zhang, Bo Liu
    2018 Volume 17 Issue 3 Pages 533-540
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The purpose of this paper is to study the seismic response of a base-isolated, concrete rectangular liquid-storage structure (CRLSS) under small-amplitude sloshing. In this study, the three-dimensional FEM of the base isolated CRLSS is established by using ADINA. The concrete material is assumed to be nonlinear and elastic, and the criterion for the small amplitude sloshing is defined to determine the seismic response of a base-isolated CRLSS under different conditions. The results show that when small-amplitude sloshing occurs and the nonlinear elasticity of the concrete material is considered, the displacement of wallboard, the height of liquid sloshing and the equivalent stress are increased with the increase in the earthquake intensity when comparing the same liquid height and different intensities of a bidirectional earthquake. The liquid height is found to affect the seismic response of the base-isolated CRLSS. The lower the liquid height is, the larger the equivalent stress is, and the greater the displacement of the wallboard and the amplitude of the liquid sloshing are.
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  • Sang-Woo Kim, Bum-Sik Lee, Young-Seek Kim, Sun-Hee Lee, Kil-Hee Kim
    2018 Volume 17 Issue 3 Pages 541-548
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This paper estimates the structural behavior of recycled aggregate concrete confined by spiral reinforcement. The main test parameters are designed to be the type of aggregates, replacement ratio of recycled aggregates, steel ratio and yield strength of spirals. Specimens subjected to concentrated axial load can be divided into two groups, natural and recycled aggregate specimens, based on the type of coarse aggregate used. The recycled aggregates are designed to be used from 0% to 100% in the specimens. Spiral reinforcement is varied up to 1.75% and 1,430 MPa for the steel ratio and yield strength of spiral, respectively. Furthermore, cover concrete and longitudinal reinforcement are neglected to estimate the pure capacity of recycled aggregate concrete confined by spiral reinforcement only. Test results showed that the structural performance of recycled aggregate concrete specimens confined by steel spirals was similar to that of natural aggregate concrete specimens, regardless of the replacement ratio of recycled aggregates, the steel ratio and the yield strength of the spirals.
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  • Chu-Tsen Liao
    2018 Volume 17 Issue 3 Pages 549-556
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    In recent years in Taiwan, pedestrians have been injured by external wall tiles falling from high-rise buildings. In numerous cases, exposure to temperature and/or seismic behavior caused the tiles to fall off. This is now treated as a public safety threat. Therefore, in 2015, the Office of Building Administration of the Taoyuan City Government started inspecting buildings that were eleven stories or higher and constructed before 1996. From 2015 to 2016, the authors inspected 298 high-rise buildings for external wall tile failures in the city as contract research. We put building risk into Levels from A to E. Levels D and E accounted for 41.6% of the 298 buildings. These were dangerous buildings that needed to be repaired immediately. Additionally, we analyzed our data based on building age, number of stories, exterior materials, the directions walls faced, and city districts. Of the buildings inspected, 84% were between 20 and 25 years old. Approximately 74% were 11 to 15 stories high. Moreover, 74.5% used tiles such as mosaic, square brick, Nikogake, or half of Nikogake. Also, 44.3% of degraded buildings were in Taoyuan District. The authors hope that the research results are a useful reference for inspection systems and that they will lead to periodic inspections.
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  • Wei Huang, Jiang Qian, Zhi Zhou
    2018 Volume 17 Issue 3 Pages 557-564
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The truncation of steel sections in Steel Reinforced Concrete-Reinforced Concrete (SRC-RC) transfer columns may lead to a distortion in the internal force transmission. A refined finite element model of SRC-RC transfer columns was developed in this study taking into consideration the effects of different confinement around concrete. According to the internal force and deformation characteristics of a transfer column, the shear capacity of the SRC-RC transfer column was investigated, and the results compared well with existing experimental results. Extensive parametric studies were conducted and crosschecked with the current code. It is found that the current specification may not always ensure the shear failure capacity since it is intrinsically affected by both the internal force and deformation characteristics of the transfer column. A modified formula has been proposed, by which more rational design of structural members may be expected, brittle failure can be avoided and ductility will be improved.
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  • Metin M. Uzunoğlu, Ercan Özgan, Tuncay Kap
    2018 Volume 17 Issue 3 Pages 565-571
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The aim of this study is to investigate the effect of hydrostatic pressure on the engineering properties of hardened concrete. To this end, a concrete column with dimensions of 100 cm width, 25 cm depth and 250 cm height was produced using C20 class concrete. While pouring the concrete, 15 cm reference cube samples were taken from the fresh concrete. After 28 days, 8 from the cube samples and 128 from different hydrostatic heights, in total 136 pieces of core samples with Ø100 mm diameter were taken and their compressive strength was determined. The average compressive strength of the reference core samples was 36.95 N/mm2 and the compressive strength of other samples changed between 37.3 N/mm2 and 43.0 N/mm2 according to the hydrostatic pressure. It was concluded that compressive strength changed between 0.95% and 16.37% according to the reference sample. Statistical analysis was conducted based on the experimental results. The compressive strength of the core samples related to its hydrostatic height and physical properties were predicted with a high reliability. A model equation was formed to convert the compressive strength of the core samples into reference compressive strength according to hydrostatic height and the convertibility coefficients were ascertained.
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Environmental Engineering
  • Masamichi Hanazato, Norimichi Suzuki, Chie Koga, Hiroko Nakaoka, Chisa ...
    2018 Volume 17 Issue 3 Pages 573-579
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    The prevention of sick building syndrome necessitates the design and construction of buildings that can maintain low concentrations of Volatile Organic Compounds (VOCs). This study aims to determine whether VOC concentrations in a new commercial bank can be reduced through the selection of building materials and monitoring of construction processes. The building was designed and constructed with close attention to the selection of architectural materials and supervision of construction. Twice during construction, indoor air samples were collected and their chemical compositions determined. The Ministry of Health, Labour, and Welfare of Japan (MHLW) guideline concentrations for VOCs were not exceeded for any of the specified chemicals, including toluene, xylene, ethylbenzene, styrene, p-dichlorobenzene, tetradecane, formaldehyde, and acetaldehyde. After construction, the total VOC concentration was 104 μg/m3. This value is substantially lower than the target value of 400 μg/m3 recommended by the MHLW. Construction of a bank building with low concentrations of indoor chemical substances can be achieved through the proper selection of architectural materials and construction site supervision.
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  • Chang Heon Cheong, Beungyong Park, Seonhye Lee
    2018 Volume 17 Issue 3 Pages 581-588
    Published: September 15, 2018
    Released on J-STAGE: September 15, 2018
    JOURNAL FREE ACCESS
    This study investigated design recommendations to reduce airborne infection risk in an emergency department by using airflow network simulation. The main design concepts include isolating the source of the airborne pathogen and increasing the ventilation rate. A conventional emergency department is selected as a base model, and influenza is selected as the airborne pathogen examined in the study. The Wells–Riley equation is used to model airborne infection risk in a zone. The simulation results indicate that airborne infection risk exists when a patient releases an influenza pathogen in the emergency department with a ventilation rate of 3 ACH according to the Korean building code. The findings reveal that isolating the airborne pathogen source and increasing the ventilation rate are good methods to prevent airborne infection risk. However, the isolation method can increase the infection risk in a zone with an airborne pathogen source. Thus, it is necessary to simultaneously increase the ventilation in a zone with an airborne pathogen source. Additionally, airborne infection risk continuously increases the cumulative exposure time, and it is desirable to increase the ventilation rate required for a zone based on the residing time of a patient releasing airborne pathogens in a target zone.
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