Wood is one of the oldest materials used for building different types of structures in many parts of the World. Turkey is a country with a wide range of building traditions and traditional houses are the most important evidence of the past life style. Traditional houses in Turkey were built mostly of wood, and timber-framed building systems have frequently been used and were common there until the 20th century. While new buildings in rural areas used traditional techniques until the middle of the last century, thanks to the development of transportation and availability of modern materials such as cement and industrial bricks across the country, the construction of traditional timber-framed houses has declined considerably. This change in modern methods of building has resulted in a loss of knowledge concerning the tradition of wooden buildings. In this study, the general structural and architectural features of traditional Turkish timber-framed houses are introduced and their layouts, plan types and frame details are presented in terms of the use of wood in construction. This study is based on observations, literature and on-site investigation.

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After four decades of Jose Luis Sert′s works, the success and failure of his buildings has now become obvious. Apart from Sert′s initial intention of design, his successful buildings attest the outcome of urban naturalization of buildings. It is neither passive adaptation of nor striking contrast to a building′s surrounding, but an active and sustaining vitalization which is latent and often assumed. The successful buildings show a concatenate response to the climate, a continuation of praxis, and an architectural contribution to urban environment, while unsuccessful buildings were lacking at least in one of the above points. Three buildings will show the range that Sert intended in accomplishing his tacit approach. First, the Holyoke Center, which was the manifestation of a city with a large building, has proven to be unsuccessful in the recent use of the building. The second building is Peabody Terrace, which expressed environmental adaptation and alternative dwelling to suburbanization through the compact massing and variegated design elements of the building enclosure. The third building is the 44 Brattle Building, which has acted as a catalyst for the enhancement of the building block for more than 40 years. These examples show the range of Sert′s initial conception and more over, their actual manifestation in the built environment.

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Based on his exploration of the ″desire to be″ in architecture, and the design principle of ″served and servant spaces,″ Louis Kahn used the composition of structural elements to reveal the quality of a space and address the issue of where to place the laboratory′s large number of mechanical ducts, pipes and conduits. The University of Pennsylvania Medical Research Laboratories and the Salk Institute for Biological Studies are two of Kahn′s most celebrated buildings. They give ample expression to his poetic tectonic thinking, as well as the spatial, technological, and aesthetic innovations he pioneered for laboratory design. This paper analyzes the spatial composition and structural system of these two laboratory buildings, as well as the way in which the mechanical services were integrated into the structure. Textual research, analysis of diagrams, and the composition of three-dimensional illustrations were used to investigate how, in the process of giving shape to a space, Kahn made full use of the unique qualities of his materials to give expression to the concept of rational architecture. This paper then goes on to investigate the unique features of Kahn′s tactic of incorporating the mechanical services into the structure of these two labs. The results indicate that complying with the structural order was Kahn′s main strategy for integrating the mechanical ducts pipes and conduits into the space.

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In this paper, a traditional Korean residence, Yeongyeongdang in Seoul, is selected to demonstrate the achievement of environmental sustainability in the formal composition of traditional Korean architecture. Using the computational analysis features of Ecotect, as performed on geometric models of the Yeongyeongdang complex, the paper highlights the method of articulating environmental factors in the design of its spatial systems, which were heavily influenced by social hierarchy during the Joseon dynasty (1392-1910).

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This study aims at identifying the time of advent of the concrete floor and the development of both steel girders and concrete floor structures in the early 20^th century in Korea. The subjects of this study include the Seokjojeon in Deoksu Palace, the Bank of Chosen, and the Chosen Hotel which was destroyed. It seems that the advent of concrete floor structures in Korea started with construction of the Seokjojeon in Deoksu Palace at the end of the 1890s. The concrete floor structure was also attempted with steel girders in the Bank of Chosen and Chosen Hotel, which were constructed around the same time. Seokjojeon and the Bank of Chosen used concrete of 12cm thickness with spacing of 75cm after placing corrugated steel plates of 3.6mm thickness between the beams (J.B). The Chosen Hotel used corrugated steel plates between beams at a spacing of 170-200cm, inserted flat bars of 2.54cm width and 0.16cm thickness at a spacing of 23cm, and then laid concrete from 12cm to 24cm in thickness. The Chosen Hotel shows floor structure details including the insertion of flat bars at a specific spacing instead of unreinforced concrete, which could be seen as the initial stage for subsequent reinforced concrete structures.

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This study focuses on the spatial transformation of Taipei in colonial Taiwan from 1895-1945, and draws attention to the relationships of the following terms: the colonizer, the colonized and the urban form. The article consists of three main sections: introduction of current scholarship and major debate; discussion on the theories in relation to space and body; Taipei as a case study in light of ″city-as-text″ and ″text-as-city″ contributed by both the colonizer and the colonized subjects. The purpose of this article is to probe and to discover whether the construction of such a colonial modernity in Taiwan was a process not anticipated by its contemporary colonized subjects.

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Reducing earthquake disasters in non-engineered houses is an acute issue because they are a main cause of human casualties worldwide. Since non-engineered houses differ from engineered houses in many respects, the authors conducted a comparative study and clarified the characteristics of the former. Based on this study, they found that reducing disasters in non-engineered houses would require appropriate seismic technologies to be adopted by communities and effective channels to disseminate technical knowledge. Further, a comprehensive approach covering a wider field of activity and effort was found to be necessary as users/dwellers of non-engineered houses are low/middle-income people and a professional housing supply sector usually does not exist for such houses. This paper reports on the characteristics of non-engineered houses, indicates the items to be tackled in reducing earthquake disasters in such dwellings, and proposes an approach to safer non-engineered houses consisting of key issues and a comprehensive approach.

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The refurbishment sector has the potential to keep growing and contribute to the growth of total Malaysian construction output. The increased number of obsolete and deteriorating buildings, coupled with the limited land for new development will contribute to increased demand for refurbishment works in Malaysia. However, the performance of refurbishment projects in most developed countries is unsatisfactory. One of the sources of unsatisfactory performance is related to design problems. This study analyses the variables that could be used for measuring design performance and reviews design performance of refurbishment projects in Malaysia. The study concludes that the design performance of refurbishment projects in Malaysia is used in three-quarters of refurbishment projects. The percentage of completeness of design before work starts on site was more than 80 percent. The additional construction cost attributed to design changes during the construction stage was more than 20 percent of the original estimated cost.

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The high-rise apartment is considered to be a representative housing type in Korea and many people believe this housing type is inevitable because it provides convenience and economy without consuming vast amounts of scarce land resources. However, many debates have been arisen because some have expressed concern that high-rise living may jeopardize the health of residents. The objectives of the current study are to analyze the impacts of the residential floor level of high-rise apartment buildings on the health status of residents and to identify the detrimental factors. The study methods are as follows: (1) Based on the previous studies, detrimental factors concerning the health status of residents, which are currently being raised as an issue, have been analyzed. (2) An analysis has been carried out on residents who have received a medical check-up at the health promotion center of a tertiary medical center, in order to ascertain the correlation between their present medical symptoms and their residential floor level. (3) Based on the results of primary medical examinations, an analysis has been performed to identify the correlation with the residential floor level. Thus, detrimental factors regarding the health status of residents have been extracted based on objective data. The results were as follows: (1) Homogeneous results indicating that residents at a higher-floor level of apartment housing had a poor health status are not reliable. (2) Higher-rise living may potentially have a detrimental effect on the respiratory system. (3) Lower-rise living may is exposed to inflammatory factors probably due to the exterior environment. The focus of this study has been to find out whether there is a significant correlation between high-rise living in apartment housing and the health problem of residents. Further study is essential to find out the detrimental factors affecting the health status and to prepare the appropriate measures. Henceforth, further systematic studies are warranted to protect the residents at high-rise apartment buildings.

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This paper explores the concept of adaptability through a study of customization work on Indonesian multi-storey housing. Significant differences in interior plans and renovation, modification and customization methods in public rumah susun and private apartments enable small-scale post-occupancy adaptability using low-level industrialized building techniques. This study reveals the importance of the building system for enhancing building service life by differentiating building components according to users, decision control and customization method. The findings suggest two adaptability concepts for infill housing for rumah susun and apartments: adaptable design and affordable production.

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The purpose of this paper is to introduce and analyze the design process and issues of a new interdisciplinary science laboratory building. Unlike conventional science buildings that focus on one type of discipline, new interdisciplinary science buildings are a combination of two or more different disciplines. By illustrating a specific example of the design and construction of the Biogeochemistry (BGC) building and the Marine Research Facility (MRF) building at Woods Hole Oceanographic Institution (WHOI) ¹, the main issues pertaining to the new lab design will be covered. In discussing the development of the project, campus planning, laboratory planning, public space planning, cladding design, Mechanical Electrial and Plumbing (MEP) system coordination, interior design, laboratory bench design, and inherent design issues in interdisciplinary science labs will be reviewed.

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Urban design principles in many Chinese cities are similar to each other without considering regional climate variation. Especially in winter cities, without climate responsive urban design principles, most public open spaces are turned into useless places in winter, which is not only because of the low temperature, but is also due to strong wind influenced by the design of surrounding buildings. Therefore, by using wind tunnel simulation, this paper presents one scientific approach to developing original urban design guidelines for cities in cold regions. Taking typical blocks in downtown Shenyang, China as a case study, a series of high-rise buildings with various concepts of podium design are tested in a wind tunnel. According to the results of experiments, the authors concluded several urban design principles concerning regional climate for open space design and streetscape design in downtown Shenyang.

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This study aimed to clarify room use in the dwelling units of elderly Chinese couples in their daily lives. For this purpose, the authors used Active Radio Frequency Identification technology (Active RFID) to identify the room (Base) in which elderly Chinese couples stay for the longest duration between rising and going to bed. Findings showed that the surveyed couples could be classified into two types: i.) Those who use and share the bedroom as Base, and ii.) Those who use the living room as a shared Base in the evening and tend to use different rooms as Base during the day. Most elderly men stayed in the same Base during the day, while the elderly women used multiple rooms in the morning. The Base obtained by objective observation (Objective Base) and the Base identified by subjects (Subjective Base) were more in accord during the day. This shows that the Base in the mind of the subjects indicated the room where they spent the most time during the day. In summer, they also chose a north-facing or windowless room as Base. Additional interviews revealed that this choice was made because such rooms were cooler.

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The purpose of this study is to explore the behaviors of the residents of a Taiwanese nursing organization through their style of sharing bedrooms with other residents. This study examines day-to-day behaviors, and the differences and connotations. The investigation employs the environmental behavioral observation method in order to observe and maintain records of the residents′ behavior. As per this method, there are six types of behaviors, namely, basic behavior, quiet behavior, social interaction behavior, recuperation behavior, mobile behavior, and leaving the bedroom (social withdrawal behavior). These behaviors are studied in the context of two shared-room styles, namely, two-person bedrooms and six-person bedrooms. It was found that residents sharing two-person bedrooms exhibit an increase in withdrawal behavior; however, they are more active than residents sharing six-person bedrooms, in terms of basic behavior and social interactions. Thus, this study finds that the number of residents sharing a bedroom influences their day-to-day behavior.

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The sprawl of Egyptian cities has lead to the encompassing of adjacent peripheral villages into their urbanized areas. These encompassed villages have been undergoing uncontrolled physical transformations, causing them to lose their original identities but rarely gain full urban ones. This study aims to clarify the physical transformations occurring in such areas, while highlighting anticipated problems in continued uncontrolled transformations, for the purpose of further study on control strategies. A field survey was conducted in the El-Ekhsas neighborhood of El-Minya City, Egypt. Specifically, the study clarified physical transformations by investigating: 1) the changing urban fabric from an organic to more grid-like, and eventually to a random linear structure, 2) the decrease in plot areas due to inheritance practices and a linear subdivision system for agricultural land, and 3) changing trends in building heights and construction materials. The main existing physical problems are then summarized as: 1) inadequacy of street networks concerning vehicle access, 2) incompatibility of decreasing plot areas to the application of planning laws, and 3) lack of maintenance concerning streets, buildings, and infrastructure. Finally, the study suggests the formation of a partnership between villagers and the city government to establish special local bylaws and improvement projects applicable to encompassed villages.

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The phenomenon of unsold new housing stocks is an important indicator in the housing market system; it is directly related to the profitability of the construction business and appears as a result of an imbalance in the demand and supply of houses. Changes in demand-supply because of various factors are another phenomenon that occurs in the housing market. It is considered that these changes in demand-supply are closely related to the unsold new housing stocks. Therefore, we analyze the relationship between demand-supply in the housing market and unsold new housing stocks using the vector error correction model. We used data from Seoul as the spatial scope of this study, and the temporal scope of time series data ranged from July 2001 to July 2009. To obtain the time series data, databases of the Ministry of Land, Transport and Marine Affairs, Statistics Korea, CERIK, and Kookmin Bank were utilized. The results of variance decomposition analyses indicated that for changes in unsold new housing stocks, the explanatory powers of housing selling price indexes and housing loans were high while the explanatory powers of production factors were relatively low. Based on the results of impulse response analyses, the quantity of unsold new housing stocks showed larger changes in response to the impulses of housing prices and housing loans than to the impulse of production factors. Also, it was indicated that, among the production factors, unsold new housing stocks showed a pattern of continued change in relation to the financing status of suppliers while showing impromptu responses to the impulses of the material or manpower situation but no continued change.

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This research focuses on the renovation of historical buildings of Zhuyangxin Plaster Store, Hangzhou, China. By following three architectural design strategies, namely protecting the surrounding environment, rejuvenating the commercial and cultural function and recovering the original appearance, the historical buildings are to be retrofitted to achieve a sustainable regeneration. Meanwhile, based on an on-site investigation into the present residential environment of the buildings, suitable architectural technologies to improve the residential environment are analyzed from the aspects of envelop, facilities, sun shading, passive technology and sunlight utilization. After some retrofit measures were adopted for the envelop of the historical buildings, the simulation results showed that not only the thermal and light environment will be improved, but also energy efficiency of 50.34% can be achieved according to the standard in China.

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This study investigates the domestic spatial use patterns, trends, and organization of inner city dwellings in the Vientiane Capital Province of the Lao Peoples Democratic Republic (Lao PDR), focusing on the Mekong River residential areas. The results clarify the various issues related to house modification and expansion that can be applied to city planning and urban design strategies. To accomplish this, a field survey was conducted in nine randomly selected villages within the Sisattanak District of the Vientiane Capital Province. The samples were classified into four defining periods from 1945 to the present: (A) French Colonial (1945-1954), (B) American Colonial (1955-1975), (C) Post-Independence (1976-1986), and (D) Modern (1987-present). Discriminant analysis was used to classify the ratio into groups to support the multiple discrimination function of HAYASHI (Suryuka Riron II). Furthermore, an analysis of variance (ANOVA) was used to find size homogeneities within the residential areas.

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In a price-driven, low-bid system a cooperative contract may be helpful in reducing problems that arise from competitive bidding. In this article, the authors examine the stability of cooperation between owners and contractors through a repeated game model with provident partners. Firstly, the profits of defecting and cooperating partners are compared to determine whether there is motivation to defect. This comparison is achieved by using a dynamic model to calculate the loss and recovery of trust. Secondly, the authors examine the relationship between stability and its influential factors under the condition of partner changing. The authors′ examination reveals that stability of cooperation correlates negatively with both the recovery velocity of trust and the probability of undiscovered defection, but has a positive correlation with the number of consecutive defections. Furthermore, the possibility of extra profit is the key motivation for unilateral defections under the condition of fixed partners. The authors conclude by proposing methods for maintaining the stability of cooperation.

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Individualized care in small-scale nursing homes is becoming more prevalent in Japan in order to meet the personal needs and respect the dignity of the elderly. Since the philosophy of care and the subsequent activities of nursing home staff are changing drastically with the increase in individualized care, creating a comfortable care environment and providing a well-designed space must be taken into consideration. This paper attempts to clarify the actual conditions of a care environment in which individualized care is provided by analyzing the activities of both the residents and care staff. Data were collected from behavioral observations and examination of patterns in the use of space at an elderly care facility that has both Group Living and a Day Service. The results of this paper are as follows: 1) Several types of support, such as Direct care, Conversation care, Organizing groups and Beholding occur at the same time with a varying number of participants, and change depending on the situation. 2) While Direct care and Beholding are the main types of support for Group Living residents, for those using the Day Service, Conversation care is the main type. 3) The care environment should comprise connected spaces, such as a kitchen and dining room, rather than individual or constricted spaces.

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This paper presents an experimental result of the damping ratio and related mechanical properties of rubber concrete made by partially replacing the fine aggregate in concrete with rubber powder. The goal is to study the relationship of them with various rubber replacement ratios. First, the effect of the mixing ratio on the mechanical properties, the compression strength and Young′s Modulus, of concrete cylinders with different rubber admixtures, including #10 and #40 rubber powders, is discussed. Second, the results of impulse experiments to determine the damping ratios of the rubber concrete cantilever beams are presented. The results reveal that rubber powder increased the damping ratio, and the addition of not more than 7.5% admixture caused at most a 156% increase in the damping ratio with #10 rubber powder, and 194% with #40 rubber powder. Simultaneously, however, the compression strength is reduced by 10-27% with #10 rubber powder, and by 13-41% with #40 rubber powder.

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The deformation of building frameworks can lead to critical disasters such as building collapse. Loads, thermal expansion and creep are generally known factors, which cause deformation. High temperature due to fire can also be one of the major factors since concrete deterioration can affect the performance of building structures and eventually can weaken the frameworks. It is, however, difficult to estimate the influence of fire on concrete structures and evaluate the performance of fire resistance design. Many researchers have carried out experiments using small-scale specimens to tackle this issue and it was shown that specimens can reflect the real behavior of structures reasonably well. Nonetheless, it is challenging to achieve uniform temperature rise throughout the specimens while heating the structure as concrete has low thermal conductivity. Many different heating methods were used in recent studies to overcome this problem; however, one cannot compare the results directly to other results due to the variation of the experiment conditions. In this study, therefore, a new heating and loading method was suggested which combines the existing heating systems. Several experiments were carried out to show that a new method can maintain uniform temperature while heating so that the experiment can produce more accurate data.

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In this paper, a model of the dynamic corrosion-induced cracking process of reinforced concrete (RC) structures considering the influence of initial defects in concrete cover caused by settlement of concrete is presented. Formulas for predicting time to initial defects initiation, time to cover cracking, threshold expansive pressure and critical weight loss of reinforcing steel are proposed. Comparisons with published experimental data show that the predictions given by the present model are in a good agreement with the experimental results and have better precision than other existing models. Finally, the influences of initial defects on critical corrosion-induced cracking indexes, such as time to initial defects initiation, time to cover cracking, threshold expansion pressure and critical weight loss of reinforcing steel are investigated. It was found that the initial defects have a great effect on critical corrosion-induced cracking indexes. These critical indexes decrease sharply when the size of initial fine crack is less than 1 mm or its number is smaller than 2 respectively, but tend to moderate when the size of the initial fine crack is more than 1 mm or its number is larger than 2. Therefore, it is important to improve the compactness of concrete in order to improve the durability of RC structures.

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Reinforced concrete shear wall is one of the main lateral resistance members in tall buildings. A further understanding of shear walls is believed important to the seismic design. To day, it is recognized that boundary elements will contribute to the seismic behavior of shear walls, though the extent still remains vague and evidence is seldom given by relative experiment. Further-more, the nonlinear capacity evaluation method of shear walls is also a difficulty, especially considering the boundary elements. This paper aims to extend the relevant existing studies with the following two programs: (1) The experimental study of shear walls with different stirrup ratios in boundary areas; (2) A numerical simulation study of the three specimens. A finite element program SAPCAD is applied to simulate the seismic behavior of the shear wall specimens with different boundary condition. The experimental study and the numerical simulation in this paper indicate that: (1) A properly distributed boundary element may be helpful to avoid local crush and brittle failure; (2) The lateral load-carrying capacity could be influenced by stirrup bars; (3) The cyclical load simulation results drawn by SAPCAD agree with the test results. And some of the stirrup effect could be evaluated by this kind of simulation.

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In this study, to reduce the HHV of the high-strength mass concrete at early ages, PCM that could absorb the occurred hydration heat was applied, and the changes of autogenous shrinkage and the relationship between the hydration temperature and autogenous shrinkage were investigated. The addition of the PCM leads to a decrease of the fluidity and an increase of the air content in concrete. The acceleration of the cement hydration process by the PCM leads to an early setting and a higher development of the compressive strength and elastic modulus of concrete at very early ages. The function of PCM could be worked below the original melting point due to the eutectic effect. While the hydration temperature and HHV of high-strength mass concrete can be decreased with the use of the PCM. A close relationship could be found between the hydration temperature and autogenous shrinkage; the higher the HHV, the higher the ASV and the greater the ultimate autogenous shrinkage.

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In this study, an experiment on shear walls has been carried out to determine structural reliability; this is necessary information for practitioners when constructing non-engineered houses or earthquake-resistant residential buildings. Analytical and numerical analyses have also been conducted, to establish an appropriate method to estimate the performance of this kind of structure that can be used in the future. A 3D specimen made of a Laminated Veneer Lumber (LVL) structural frame sheathed by Fiber Cement Board (CFB) with shear wall elements embedded in the wall without openings, termed Type 36 hereafter, was tested in the study. Static push and pull cyclic load was applied at the top of the specimen to simulate the seismic load. The study found that the Non-Engineered earthquake resistant Type 36 house needs two shear wall panels without openings; these walls act as structural elements, to resist seismic force, at the zone with the highest risk of earthquake in Indonesia. The structural system consisting of wood and cement-based building materials, shows sufficient resistance to earthquake, and so the shear wall panel can be used as a structural element in houses and earthquake-resistant residential buildings.

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The strength of reinforced concrete members may vary from the calculated or the nominal strength due to variations in the material strength and dimensions of the element. Statistical descriptions of the variabilities in loads and strengths are required in all studies pertaining to the safety of reinforced concrete members. Therefore, this paper recommends a number of values for the coefficient of variation of concrete, reinforcement, dimension and load to be used in the probability analysis. Also, this study analyzes reinforced concrete members using the Advanced First Order Second Moment (AFOSM) method using the statistical characterization of variables. This study shows that Bayes′ theorem is an effective tool for updating prior probabilities when the value of a random parameter is known. Finally, the results in this paper contribute to the limit state reliabilities implied in the current design of reinforced concrete elements.

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In this study, the authors′ plan to investigate the status of steel pipe scaffolding assembled on domestic construction sites, to use specific tests to determine whether the torque of the clamps surveyed satisfies the test criteria specified in the functional examination standard of the provisional facility, to compare and analyze the marginal load of buckling using main variables (by size, construction work type) by applying the spring coefficient of the clamps as calculated using the MIDAS structural analysis program and, with all these results, to propose improvements and direction for the future. Ultimately, the goal is to establish measures to prevent accidental falls due to the collapse of improperly assembled scaffolding. The result of functional certification standard tests for clamps showed that the fastening strength of clamps on the main members (poles, wales, and joists) reached only 63.3% (13.03 average maximum load/35Nm Standard fastening strength × 100) of the standard fastening strength (35Nm), indicating that certified clamps were not used. Accordingly, there is a necessity for thorough public relations, education, guidance, and examination to allow workers to engage in safety management and understand the importance of clamp fastening strengths on outdoor steel pipe scaffolding.

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Integrated structural and materials design (ISMD) represents a new design approach that combines materials and structural engineering for the purpose of more effectively achieving targeted structural performance. Performance based design of structures provides flexibility and incentive to select composite materials with properties that efficiently meet the structural performance target. Currently, modern materials engineering provides tools for tailoring material ingredients for desired composite properties. Thus, the integration of structural and materials design is a natural joining of these technical fields. In this paper, the ISMD concept is applied to develop white Engineered Cementitious Composites (White ECC) thin panels for architectural applications. Finite Element Analysis (FEA) is carried out in order to transfer targeted structural performance to required material properties. Based on the simulation results, White ECC is developed to meet the desired mechanical properties.

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The present study is the first investigation in Japan to monitor the interstitial hygrothermal environment of a straw bale wall at various depths and heights. Extensive interstitial monitoring has been conducted on a straw bale building in Kyotango City, Kyoto Prefecture known as ″Shinrinnobokujo-tango″. The purpose of the present study is three-fold: (1) Determine if the interstitial hygrothermal environment of Shinrinnobokujo-tango′s south straw bale wall is homogenous, (2) elucidate the interstitial hygrothermal environment of the south wall, and (3) evaluate the potential for mold growth. As a result of the study, the interstitial hygrothermal environment was found to vary by height and depth. In winter, the interstitial area with the lowest temperature and highest relative humidity was the upper, exterior portion of the wall. In summer, the area with the lowest temperature and highest relative humidity was the lower, interior portion of the wall. Mold growth was predicted within the straw bale wall, with the greatest risk being the upper, exterior portion of the wall in winter and lower, interior portion of the wall in summer. These results suggest the need to control moisture in straw bale walls in Japan.

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An experimental investigation was conducted to examine the hysteretic behavior of ultrahigh-strength concrete tied columns under stress to determine the effect of the volumetric ratio of transverse reinforcements on column deformability. Eight 1/3-scale columns were fabricated to simulate a half-story of actual structural members, and their axial load ratio, transverse reinforcement configuration, and transverse reinforcement volumetric ratio were changed during the simulation. The column deformability was found to be affected by the configurations and volumetric ratios of the transverse reinforcement. The column behavior was particularly affected by the axial load ratio as compared to the amount and configuration of the transverse reinforcement. To improve the ductility behavior of an RC column using ultrahigh-strength concrete in a seismic region, a volumetric ratio of transverse reinforcement was suggested for all data satisfying the required displacement ductility ratio of over 4. The results indicate that the effective lateral confining reduction factor λ^c, calculated by considering the configuration and spacing of transverse reinforcement and the axial load ratio, is reflected in the volumetric ratio of transverse reinforcements.

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This study of the traditional sericulture residence, located inside the Minkaen, Jidayubori Park, Setagaya Ward, Tokyo, Japan, aims to clarify the environmental characteristics of a sericulture building from the engineering point of view. In sericulture, the silkworms are raised at different locations depending on their age. Therefore we describe the actual conditions of the thermal environment such as temperature and humidity when the silkworm is breeding, and the air quality such as CO2, CO, VOC, and carbonyl compound from the silkworm hearth. In addition to these factors the ventilation rate in each part of the traditional house corresponding to sericulture is determined. Moreover, the ventilation performance of the attic and the monitor roof is investigated. The mechanism of thermal conditions, IAQ and ventilation rate was clarified in this paper for the first time using the three-dimensional heat fluid simulation software. As described thus far, we have clarified the environmental situation in a sericulture house from the engineering point of view.

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Energy-efficient buildings are essential to reduce greenhouse gas emissions. However, improved energy efficiency may also bring about a rise in construction costs. If design variables can be prioritized according to their cost efficiencies, energy-efficient buildings can be designed more cost-efficiently. The aim of this study is to analyze the cost efficiencies of design variables related to energy efficiency of the apartment complex. After making 78 alternatives for 29 target items, each alternative′s increased amount of construction cost and decreased amount of energy cost against the baseline model were then estimated using actual price data and the assessment methods of the Building Energy Efficiency Rating System that has been implemented in Korea, respectively. The life cycle cost, net present value, internal rate of return, and payback period of each alternative were shown as cost efficiency indexes. The order of priority of each alternative was presented and very cost-efficient alternatives were suggested.

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This paper reports simulation results of the potential fiscal benefits from investment in improved indoor environmental quality in school buildings. Improving indoor environmental quality can result in substantial benefits due to improved academic performance, but it can also result in increased energy and heating, ventilation, and air-conditioning (HVAC) maintenance costs. The aim of this paper is to demonstrate the cost-effectiveness of additional indoor environmental control by HVAC and the associated benefit of improved academic performance in a limited-scale school building model. This study estimated the impact of an increased ventilation rate and an alteration of target room air temperature on energy costs and on academic performance. The annual benefit due to improved thermal conditions (room air temperature) was up to five times higher than the benefit of increased ventilation rate per person. Lifecycle cost analysis showed that the benefit (improved academic performance) resulting from better indoor temperature conditions was up to 20–40% against the increased costs (increased HVAC total cost) of a few thousand JPY per year [JPY/year/person].

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This study investigates the influence of cavity depth and the conditions of louvers on indoor thermal environments to propose optimum configurations of solar collecting window systems that can be effectively applied to double skin envelopes. Field measurements were performed for a reduced-scale mock-up model to represent the analysis results for a full-scale model. Computer simulations were performed using computational fluid dynamics (CFD) under a variety of cavity and horizontal louver conditions to validate the results from the field measurements. Two theoretical computation models, namely the k-e RNG and k-e standard models, were applied to the simulations. The results of field measurements imply that a cavity depth of 0.2 m was most effective in supplying air from a cavity to an indoor space with the required velocity and temperature. The validated computer simulation results imply that the k-e RNG model was more effective than the k-e standard model in predicting the properties of airflow in cavities where turbulent patterns occur due to the buoyancy effect. According to the analysis based on the k-e RNG model, a cavity depth of 0.2 m appeared to be optimum to achieve the required ventilation rates with energy savings. The temperature and velocity of air supplied from the cavity to the indoor space was most effective when the tilt angle of the horizontal louver was 45^o. While airflow passed through the cavity exchanging heat with the louvers, it was not significantly blocked by the tilted louvers. This improved natural convection and ventilation rates in the cavity. This study suggests that the solar collecting window system could be effectively applied to building envelopes in winter.

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This paper presents an application of the artificial neural network(ANN), which is a generic technique for mapping the nonlinear relationships between inputs and outputs without knowing the details of these relationships in building control system. The purpose of this study is to develop an optimized artificial neural network model to determine the optimal pre-cooling time in office buildings. For this, programs for learning of an ANN model based on back-propagation learning and predicting room air temperature based on the finite difference method were developed, and learning data for various building conditions were collected through program simulation for predicting room air temperature using systems of experimental design. Then, the optimized ANN model was presented through learning of ANN and its performance to determine the optimal pre-cooling time was evaluated.

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It is generally acknowledged that non-closed space can be more easily adapted to family lifestyle changes in terms of house planning today, but some residents have raised the issue of indoor environment in the non-closed space. The aim of this paper is to understand how environmental factors can be changed according to different furniture layouts and to examine how residents respond to the environment condition in different non-closed spaces. The study utilized computational building simulations to understand the environmental condition and observes the residents′ behavior to understand the living style of different furniture layouts. From the simulation results and observation of behavior, the paper compares the environmental condition and the living style to interpret the cause and effect between the environment and behavior. SI housing (Skeleton and Infill Housing) can be assumed as one of the eligible examples of non-closed space and the study selects an existing SI housing unit to conduct the test. It was found that the environment condition is one of the important factors that influence behavior, and a layout with various environment conditions allows the resident to behave with more ease within their preferred environment condition.

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There are both positives and negatives to constructing high-rise buildings in high population densities of large cities. The negative effect of oppressiveness will be the focus of this paper. Oppressiveness is defined as the negative feeling resulting from being surrounded by high-rise buildings. Building oppressiveness when combined with other urban stresses contributes towards making compact cities unsustainable. In other words these negative psychological factors of the environment are barriers to achieving urban sustainability. Therefore it is important to find ways to mitigate the negative psychological effects of high-rise buildings in order to improve the benefits of compact cities. This research assesses the psychological effect of green building façades and trees in Tokyo while taking into consideration a real urban environment. Within the context of the goal of ″Green Urbanism″ this research also measures and compares the effect of these two different types of greenery on residents′ psychology. The methodology consisted of two experiments that were conducted in the Hongo area of downtown Tokyo. The aim was to assess the effects of green façades and trees in terms of environmental psychology and compare them. The results showed that the effect of greenery on the facade of buildings is not as positive as the effect of a tree-lined street. Trees are significantly more effective in mitigating the perception of oppressiveness. The results are important for urban designers and government policy makers.

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A series of studies on the subjective response to aircraft, railway, and road traffic noise has previously been carried out. However few studies have examined the optimal physical parameters for this type of measurement and evaluation. To date, several physical parameters, such as the equivalent sound level (L_eq), day-night average sound level (L_dn), and day-evening-night average sound level (L_den), have been used to evaluate various types of transportation noise. However, physical parameters that are universally applicable to all types of transportation noise have not been developed. The present study was designed to analyze the relationship between transportation noise and the subjective response. The study is currently in the preliminary stages of developing a physical parameter that can evaluate both individual and combined transportation noises. In conclusion, the regression model, which includes a set of variables that describe sound levels for single and mixed source noise, predicts annoyance levels with an accuracy of >95%, as measured by the determination coefficient.

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Recently, the fight against global warming is becoming increasingly important. Being major energy consumers, air-conditioning (AC) loads are gaining importance. Therefore, the effects of heat insulation methods and AC usage patterns on AC loads should be verified before a building is constructed. This paper examines the AC loads of two typical residential units of steel (S) and reinforced concrete (RC). To compare and analyze these cases, THERB, software for dynamic simulation of the thermal environment of residential buildings, is employed to simulate the loads. Three common patterns based on the lifestyle in Japan are applied in this study to show that different family makeup can lead to varying AC loads. Further, two RC units (exterior wall insulated on the inside/outside) and one S unit (exterior wall insulated on the inside) are studied. The results reveal that the high heat capacity of concrete influences the living environment and causes differences between the RC and S units. The AC load of an RC unit with an exterior wall that is insulated on the inside is lower than that of a unit with an exterior wall that is insulated on the outside and is almost equal to that of the S unit.

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