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Given the fact that the risk of construction accidents is higher than that of other industries, various academic attempts have been made to predict the risk of construction accidents. However, previously proposed risk prediction models have been limited to monotonous calculation methods based on risk frequency and risk severity. This study aimed to develop a new model that predicts risk by identifying risk factors for the specific type of construction projects and assigning weights to each of these factors. As a foundational research, this study conducted an empirical study using the Analytic Hierarchy Process (AHP) techniques. The AHP technique was used to determine the importance and weights of each risk factor. These empirical results are significant in that they can be utilized to develop rational alternatives for predicting construction accident risks in the specific type of construction projects.

The purpose of this study is to analyze the constructing process of the Ddeulzip before 1592 at the Andong Cultural Area. At the end of the Goryeo Dynasty, the first two Ddeulzip were constructed in the Andong cultural region. This house type, where prominent figures such as Toegye and Seoae were born, likely became the central residential model of the early Joseon period. In the 15th century, large-scale (inner courtyard width of 4–5 kan) and medium-scale (inner courtyard width of 3 kan) Ddeulzip were primarily constructed. By the 16th century, smaller-scale Ddeulzip with 2-kan central courtyard width also began to appear. During this time, more complex layouts such as character-shaped houses comprising over 50 kan were developed, resulting in a diverse range of Ddeulzip types. The spatial composition of Ddeulzip expanded both along rows and columns (haenggan and yeolgan), contributing to the architectural diversity of upper-class residences. Roof forms such as Seosangak and Usangak allowed Ddeulzip to be constructed on various types of terrain.

This study analyzed the supply status of public facilities and residents' perception of accessibility in 71 rural Eup and Myeon centers in 11 counties of Jeollanam-do and Jeollabuk-do, regions facing severe population decline and aging. The centers were classified into three types based on the number of facilities and their spatial concentration. A survey of 470 residents was conducted to assess the importance and satisfaction regarding accessibility. The analysis confirmed that high resident satisfaction was correlated more strongly with efficient spatial concentration (e.g., Type 2) than with the absolute number of facilities (Type 3). Essential facilities for daily life, such as public administration, finance, and healthcare, consistently showed high importance. Notably, Public Administration Facilities accessibility was the single most significant factor influencing overall resident satisfaction across all three types. Residents overwhelmingly preferred a short walking distance of within 300 meters for most facilities, indicating a strong emphasis on immediate, human-scale accessibility. In conclusion, to proactively improve the quality of life in these centers, strategies must shift from quantitative supply to a focus on maximizing convenience and optimizing pedestrian accessibility. Specifically, essential facilities must be secured within a core walkable radius (200-300 meters), and differentiated, location-based strategies that reflect the unique spatial concentration and functional characteristics of each center type are required to effectively enhance living services and combat regional decline.

As industrialization and urbanization progressed, large-scale apartment complexes, which are key elements of the residential development and development project district, served as urban elements that played a major role in the urban expansion process as a form of housing in response to economic and policy demands. In addition, the new large-scale apartment complex provides a huge scale of volume to the field of view to form an image of the entire area, create a unique landscape, and become a representative image of the area. Therefore, this study is a follow-up of the 'A Precedent Study on the Characteristics of Region Large-scale Housing Site Development Project District in Daegu City (2024)'. The purpose of this study is to find out how the characteristics of each region were implemented in the apartment complex by grasping the specific characteristics of each region's representative apartment complex based on the characteristics of each region of the project districts derived from the previous study. In this study, major apartment complexes were selected from 18 large-scale housing development projects selected for the preceding study, and the characteristics of the apartment complex were analyzed through the complex's exterior composition, complex layout, the shape of the main building, and the pasade of the main building to confirm that the regional characteristics suggested in the previous study were due to regional characteristics in apartment complexes.

Litigation associated with construction defects and quality issues in apartment housing has markedly increased in Korea. A key objective of such litigation is to estimate defect repair costs, an issue of mutual significance for both residents and project developers. This study develops a regression-based predictive model to estimate defect repair costs in apartment complexes. Based on an integrated review of prior studies, construction cost, its natural logarithm, number of dwelling units, construction period, and elapsed period were selected as major explanatory variables. When predicting the defect repair cost or its logarithmic form, the proposed model satisfied the key assumptions of regression analysis independence and absence of multicollinearity while achieving the highest explanatory power. Future research should further explore additional determinants and refine analytical methodologies for modeling defect repair costs in multi-family housing.

This study experimentally evaluated the clamping force loosening performance of a newly developed Torque-Shear Nut (TSN) under transverse cyclic loading, comparing its performance to conventional high-strength bolts (HT) and torque-shear bolts (TSB). Customized load cells recorded real-time axial forces during testing, considering two bolt sizes (M16 and M20) and four displacement amplitudes (0.5, 1.0, 1.5, and 2.0 mm) as main variables. All bolt types showed a rapid initial loss followed by stabilization; At small displacements (0.5–1.0 mm), more than 95% of the initial preload was maintained. At larger displacements (1.5–2.0 mm)residual preload reduced to about 75–80%. In contrast, Overall, the TSN demonstrated performance equivalent to or slightly superior to that of HT and TSB, confirming its practical applicability as an alternative fastening system that provides stable and reliable clamping force retention in steel structural connections subjected to cyclic transverse loading.

This study aims to derive factors for improvement in old neighborhood facilities of Daegu by utilizing data based on a Post-Occupancy Evaluation(POE) and applying Importance-Performance Analysis(IPA). Although neighborhood facilities are highly utilized by diverse populations, those constructed since the 1970s are confronted with various problems due to significant deterioration. Consequently, 1,601 survey responses were collected across three phases. By filtering this data to include only responses pertaining to buildings aged 20-30 years (old buildings), spatial improvement factors were identified, by comparing this specific group against the total responses. The result of this study is as follows; First, the analysis of major categories revealed that, unlike the total response group, the 'indoor environment and equipment' within rental spaces registered high importance but low satisfaction, with placing it in the urgent improvement quadrant. This suggests users critically evaluate rental spaces where they spend the most time. Second, in the sub-categories, parking was classified as a lesser burden, a characteristic attributed to old neighborhood facilities on parking patterns or transition distance. Furthermore, improvements are needed for public restrooms in internal common spaces. Finally, regarding the indoor environment and equipment within rental spaces, discomfort from noise was identified as a significant issue, reflecting the deterioration of the old buildings.

Defects in apartment complex impose a significant social and economic burden. Improving this situation requires effort and a change in attitude throughout the construction industry, particularly from project owners and contractors. This study used cases of apartment defect litigation to investigate whether there were differences in repair costs based on various influence factors, using a t-test. The factors examined in previous research included the type of project owner, whether the developer was also the general contractor, whether a single prime contract was used, the project's area and urban location, the elapsed time since completion, and whether a defect repair agreement was reached. The results confirmed that there were differences in defect repair costs depending on whether the project owner was also the general contractor, the elapsed time since completion (based on a 5-year period), and whether a defect repair settlement was agreed upon. To reduce defects and restore consumer trust in apartment construction projects, it can be a crucial strategy for project owners to strengthen their capabilities as general contractors and diligently carry out defect repairs.

This study analyzed the ordinances enacted by local governments in Korea for the creation of age-friendly cities. The ordinances were classified into normative, executive, and governance frameworks to examine their characteristics, and the content of the ordinances was analyzed using the physical environment elements from the WHO Age-Friendly Cities guidelines as architectural and urban planning criteria. The analysis revealed that the ordinances lacked reflection of the objectives and fundamental principles of higher-level laws, and identified the need to establish a planning system that ensures policy implementation, to lay the foundation for sustainable age-friendly city development, and to prepare detailed regulations for the concrete realization of age-friendly cities. This study suggested directions for improving local government ordinances to promote the development of a Korean age-friendly city.

This paper analysed the visual and auditory factors influencing audience seating preferences in small-scale musical theatres, aiming to create sustainable performance spaces. The venue is a versatile 300-seat space with an irregularly shaped seating area designed to enhance intimacy through a curved, staggered arrangement connecting the first and second floors. Visual images of the stage view and binaural impulse responses toward the stage center were collected at nine selected seats in situ. A paired comparison method was employed in a laboratory setting to determine visual, auditory, and seating preferences, with ten subjects experienced in musical performances and normal hearing. Auditory stimuli were convolved with vocal anechoic recordings, while visual stimuli reflected spatial depth and distance perception. Three experimental conditions—visual only, auditory only, and combined—were conducted to derive seat preference scores. Results showed that visual information was the dominant factor, as superior visuals increased preference even for seats with poorer acoustic quality. Future research will explore more immersive reproduction techniques for deeper analysis.

The seismic fragility of piloti buildings having straight plans was evaluated varying the location of core. Since piloti buildings are known to exhibit soft-story vulnerability during earthquakes, the influence of core location requires careful consideration. Four types of piloti were modeled according with the different core location within the straight plan. Based on the estimated capacity curves, the performance points were determined using the capacity spectrum method considering as a equivalent damping as well as a bilinear idealization. Subsequently, artificial ground motions compatible with the target design spectrum were employed to develop probabilistic seismic fragility functions. The lognormal fragility models, median capacities and logarithmic standard deviations, were estimated through the maximum likelihood estimation. The results confirm that the location of the core wall is a key factor governing the seismic fragility of straight plan piloti buildings, and minimizing core eccentricity is essential for achieving a stable seismic performance.

Zero energy building(ZEB) is a hot topic. In order to implement ZEB, external insulation is applied that can minimize thermal bridges on the opaque wall, but we are indifferent to the lack of insulation around the window. The purpose of this study is to analyze the decrease effectiveness of the linear thermal transmittance of L-shaped thermal bridge breaker that can prevent heat loss and internal condensation due to insulation defects resulted from finishing work around the window. By applying thermal bridge breaker around the window, we found out 63% decrease in linear thermal transmittance from 2D heat transfer analysis, 52% decrease in Equivalent U-value from the actual size plant experiment, and 50% decrease in TDR through a condensation test. It was confirmed by thermal video system that outdoor surface temperatures of a residential building were lower around 1℃ and its indoor surface temperature were 2℃ higher thanks to the L-shaped thermal bridge breaker, which indicates that condensation prevention performance is improved.

This study experimentally evaluated the long-term thermal degradation of expanded polystyrene (EPS) insulation collected from aged buildings. Thirty-five field samples with service lives ranging from 13 to 31 years were tested using the heat flow meter method in accordance with ISO 8301 and KS L 9016 to measure thermal conductivity (λ) and density (ρ). The measured thermal conductivity varied between 0.037 and 0.050 W/(m·K), with an average of 0.044 W/(m·K), representing approximately a 2–20% increase compared with the KS reference values for new EPS. The average density decreased by about 40% relative to the initial reference level. A strong negative correlation was observed between density and thermal conductivity (r = –0.732, p < 0.05), while a weak-to-moderate positive relationship was identified between density reduction and the increase in thermal conductivity (r = 0.41, p < 0.05). These findings suggest that density loss and microcell structural degradation are likely major contributing factors to the thermal performance degradation of aged EPS insulation. The regression models derived from this study provide foundational reference data for establishing correction factors that reflect the degraded thermal properties of aged insulation in building energy performance assessments and the green remodeling applications.

This study analyzes the determinants of homeownership transition intentions among public rental housing residents in Seoul who plan to move within the next five years, using data from the 2021 Seoul Public Rental Housing Panel Survey. A binomial logistic regression model was employed to examine the factors influencing residents’ intentions to transition to homeownership. The results show that 42.2% of residents with moving plans expressed an intention to become homeowners, a proportion higher than that typically observed among general renter households. Among individual characteristics, higher educational attainment, longer residence duration, and a larger household size were associated with a greater likelihood of intending to transition to homeownership. Regarding physical characteristics, living in a mixed-tenure complex significantly increased the likelihood of homeownership intention, whereas residing in Gangnam-gu, Seocho-gu, or Songpa-gu reduced it. In terms of social characteristics, experiences of discrimination and conflicts with neighbors were found to significantly increase residents’ intentions to pursue homeownership. These findings provide empirical evidence that can inform policy measures aimed at strengthening the role of public rental housing as a stepping stone to homeownership.

This study investigated how building floor area and occupant density affect heating and cooling energy demand in office buildings. Energy simulations were conducted using DesignBuilder for an office building in Seoul, Korea, covering nine floor area cases (2,500~62,500m²) at two occupancy densities (0.0538 and 0.1110people/m²). Results showed that unit floor area energy demand decreased nonlinearly with increasing building size, a trend consistent across both occupancy conditions. Cooling energy (64.87%~88.93% of total energy demand) decreased as floor area increased, while heating energy (11.07%~35.13%) increased, indicating opposing responses to building scale changes. Occupancy density mainly influenced the magnitude of cooling and heating energy demand, while the overall trend was largely governed by building floor area. Analysis by exterior zone ratio revealed that cooling energy demand decreased linearly as the exterior zone ratio was reduced, whereas heating energy demand increased in a nonlinear manner. These results suggest that solar heat gain and heat exchange through the building envelope play a more influential role than internal heat gains in determining overall building energy demand. The findings provide quantitative insight for optimizing building scale and occupancy conditions in office buildings to improve energy efficiency.