Following the social requirement to strengthen field supervision of the asbestos containing materials (ACM) abatement process with regard to asbestos school buildings, this study was conducted to understand the status and characteristics of airborne asbestos that may potentially occur after the ACM abatement process is completed. In the area where a series of asbestos abatement processes were finally completed, comprehensive area air sampling was performed. For sample analysis, Transmission Electron Microscopy (TEM) was used according to The Asbestos Hazard Emergency Response Act (AHERA) method and Phase Contrast Microscopy (PCM) analysis was also performed. Airborne asbestos was detected in 29.5% of the total samples, and the average concentration was 0.0039 ± 0.0123 s/cc (12.3 ± 38.9 s/mm2). 4.5% of the total samples exceeded the AHERA standard (70.0 s/mm2) and the average concentration was 0.0528 ± 0.0256 s/cc (167.2 ± 82.0 s/mm2). Airborne asbestos was no longer detected at the point when AHERA is exceeded after re-cleaning. Most of the detected asbestos was chrysotile (94.4%) and the structure types of asbestos were Matrix (41.4%), Fiber (39.9%), Bundle (10.8%), and Cluster (7.8%). Among the asbestos structures detected through transmission electron microscope analysis, the asbestos structures satisfying PCM-equivalent structures were found to be 6% of the detected asbestos, indicating that there is a limitation of the PCM analysis to check the airborne asbestos in that area. As a result of reviewing the status of airborne asbestos that may potentially occur and the type and dimensions of asbestos structure detected in the area, since the airborne asbestos exposure caused by poor field supervision for the ACM abatement process could not be ruled out, thorough management is necessary. In addition, the result of this study could be used as scientific evidence for establishing and strengthening policies related to ACM abatement, including cases of school buildings.

우리나라는 삼면이 바다이며 북쪽과 동쪽으로 산지가 위치하고 서쪽으로는 평탄한 지리적 특성을 가진다. 또한 계절풍, 태풍 등의 바람이 지리적 특성으로 인하여 지역마다 풍향별 풍속이 다르다. 그러나 건축구조기준(이하 KDS 41 12 00: 2019)은 전풍향에 대 해 동일한 풍속을 적용한다고 규정하였고, 이것은 상대적으로 약한 풍향에 대해 과다한 풍속을 적용할 수 있다. 이런 점을 고려하여 건 축구조기준(이하 KDS 41 12 00: 2022)에서는 합리적인 설계를 위해 풍향계수를 적용한다. 본 연구는 8개소를 대상으로 10년간의 자 료를 수집하여 사용성 평가를 위한 1년 재현기대풍속과 풍향계수를 산출하였다. 선행 연구된 논문에서 사용성 평가를 위한 1년 재현 기대풍속과 풍향계수를 산출하였으나, 이는 기상청에서 제공하는 일최대풍속으로 산출하였기 때문에 누락되는 풍속이 있을 수 있다고 판단되었다. 따라서 분풍속을 이용하여 모든 풍향의 일최대풍속을 구하였고, Weibull 분포를 통해 재현기대풍속을 산출하였다. 최종적 으로 기상청에서 제공하는 일최대풍속으로 구한 풍향계수와 분풍속으로 구한 일최대풍속의 풍향계수를 비교하여 지역별 풍향계수의 경향 및 두 방법의 차이점에 대해 분석하였다.

Structures of high-rise buildings are less prone to earthquake damage. This is because the response acceleration of high-rise buildings appears to be small by generally occurring short-period ground motions. However, due to the increased construction volume of high-rise buildings and concerns about large earthquakes, long-period ground motions have begun to be recognized as a risk factor for high-rise buildings. Ground motion observed on each floor of the building is affected by the eigenmode of the building because the ground motion input to the building is amplified in the frequency range corresponding to the building's natural frequency. In addition, long-period components of ground motion are more easily transmitted to the floor or attached components of the building than short-period components. As such, high-rise buildings and non-structural components pose concerns about long-period ground motion. However, the criteria (ASCE 7-22) underestimate the acceleration response of buildings and non-structural components caused by long-period ground motion. Therefore, the characteristics of buildings’ acceleration response amplification ratio and non-structural components were reviewed in this study through shake table tests considering long-period ground motions.

Existing reinforced concrete building structures constructed before 1988 have seismically-deficient reinforcing details, which can lead to the premature failure of the columns and beam-column joints. The premature failure was resulted from the inadequate bonding performance between the reinforcing bars and surrounding concrete on the main structural elements. This paper aims to quantify the bond-slip effect on the dynamic responses of reinforced concrete frame models using finite element analyses. The bond-slip behavior was modeled using an one-dimensional slide line model in LS-DYNA. The bond-slip models were varied with the bonding conditions and failure modes, and implemented to the well-validated finite element models. The dynamic responses of the frame models with the several bonding conditions were compared to the validated models reproducing the actual behavior. It verifies that the bond-slip effects significantly affected the dynamic responses of the reinforced concrete building structures.

In this study, an incremental loading test of the HRS(Hybrid Rubber Slit) damper was additionally performed to define the physical characteristics according to the incremental test results, and an analytical study was performed according to the damping design procedure by selecting an example structure. As a result of performing seismic performance evaluation before reinforcement by selecting a RC structure similar to an actual school structure as an example structure, the story drift ratio was satisfied, but some column members collapsed due to bending deformation. In order to secure the seismic performance, the damping design procedure of the HRS damper was presented and performed. As a result of calculating the amount of damping device according to the expected damping ratio and applying it to the example structure, the hysteresis behavior was stable without decrease in strength, and the story drift ratio and the shear force were reduced according to the damping effect. Finally the column members that had collapsed before reinforcement satisfied the LS Level.

Architectural Monuments have to overcome the challenge of time due to physical properties. The fundamental issue must be grounded in an understanding of history and art to overcome this challenge and make them sustainable. Many efforts to preserve the monuments through the 19th century and at the beginning of the 20th century to record them in scientific form were successful. To be aware of the meaning of the art and not to be ‘barbare’ anymore was behind the promotion of these activities. Above all, the 19th-century French architect Viollet-le-Duc contrasted the concept of barbarism with the concept of art and tried to redefine architecture as art. The ritual to escape ‘barbare’ played an important role in the end. This consciousness was also at work in the propaganda for the preservation of medieval architectural monuments in France, led by intellectuals such as Rodin. Also, the concept of ‘barbare’ served as an important yardstick whenever the cause of their loss was questioned while important monuments were destroyed in the First World War. From the viewpoint of Germany, Dehio was the pioneer of the preservation movement and documentation of monuments. The principle he advocated was preservation, not restoration. The historian Pevsner, who moved to England, also surveyed monuments in various parts of England and left them in the same format as Dehio. These facts show that architecture as art plays a fundamental role in the history of human life.

Recently, the number of cases of fire spreading due to exterior materials of buildings is increasing. Due to the nature of modern architecture, which emphasizes the aesthetics of buildings, because buildings pursue a splendid appearance, they are inexpensive and have relatively good insulation performance, but an increasing number of buildings are adopting insulation materials that have poor fire safety performance. The risk of spread is also greatly increased. Since the exterior wall of a building is made of a variety of materials and structures, it is composed of a combination of several elements, including materials such as insulation and finishing materials. Therefore, it was determined that it was necessary to introduce a more systematic evaluation method for building exterior materials, and to improve the system reflecting this, away from the existing evaluation method that only checked the fire safety performance of finishing materials.

본 논문의 목적은 건축물을 드론으로 계측하여 드론의 비행 및 촬영 변수에 따른 계측 정확도를 분석하는 것이다. 드론의 비 행 및 촬영 변수는 비행고도 3가지(50m, 60m, 70m), 중복도 4가지(60%/60%, 60%/80%, 80%/60%, 80%/80%), 카메라 각도 2가지(45°, 90°), 속도 2가지(2m/s, 최고속도)이며, 총 48번을 계측하였다. 드론으로 계측하여 얻은 3D 데이터와 실제 건축물의 길이를 비교하였으 며, 드론의 비행 속도가 느릴수록 정확도가 높게 나타났다.

When compact HVAC is applied to a building, various variables exist in performing the functions of air conditioning, ventilation, and hot water supply of the building, and various experimental and empirical evaluations according to the energy performance evaluation method of the building occur. We are going to present research data for preparing domestic evaluation standards for energy evaluation methods for compact HVAC and zero-energy buildings to be applied in the future.

The precast-buckling restrained braces(PC-BRB) reinforced with engineering plastics that can compensate for the disadvantages in the manufacturing process of the existing buckling restrained brace. In this study, to examine the applicability of PC-BRB to actual structures, example structures similar to school facilities were selected and the reinforcement effect was analyzed analytically according to the damping design procedure of PC-BRB. Load-displacement curve through the incremental loading test appeared similar to the bilinear curve. Applying test result, Analytical model of PC-BRB model was constructed and applied to the example structure. As a result of the analysis, the PC-BRB showed stable hysteresis behavior without lowering the strength, and the inter story drift ratio and the shear force were reduced due to the damping effect. In addition, the reduction ratio of the shear force was similar to the reduction ratio assumed when designing the damping device.