중공형 RC 슬래브의 소음 및 진동 감쇠성능에 대한 연구

김동백,김인배,김종훈,이재원 한국재난정보학회 2019 한국재난정보학회 논문집 Vol.15 No.2

연구목적: 철근콘크리트 슬래브에 발생하는 소음 및 진동을 저감하기 위하여 중공부를 설치하거나 중공 부에 액체를 채워 설치한 후 감쇠성능을 실험적으로 수행하고자 한다. 연구방법: 중공율을 실험 변수로 하여, 충격하중을 가했을 때 각 시험체의 감쇠율과 강성을 구하여 수치해석에 대한 감쇠율과 강성의 차이 를 알아낸다. 또한, 중공부의 50%를 액체로 채운 시험체의 감쇠율과 강성의 차이를 비교하여 감쇠효과를 검토한다. 연구결과: 중공부가 있는 실험체와 없는 실험체의 내력의 차이는 5% 정도로 오차범위에 있으 므로 구조적인 문제는 없는 것으로 판단되며, 중공부에 액체를 주입할 경우 감쇠율이 증가함으로 소음이 나 진동도 저감할 수 있을 것으로 판단된다. 결론: 중공율이 20%이하에서는 감쇠효과가 거의 없고, 30% 일 때 감쇠효과가 나타났다. 그러나, 실험체의 중공부에 액체를 주입하였을 경우는 감쇠율이 증가하는 것 으로 나타남으로, 중공부에 액체를 주입하면 소음이나 진동의 감쇠효과를 얻을 수 있을 것으로 사료된다. Purpose: To reduce the noise and vibration of reinforced concrete slab structures, the damping performance is to be performed experimentally after installing hollow core or filling it with liquid. Method: Using the hollow rate as an experimental variable, the damping ratio and stiffness of each test specimen at impact load are obtained to determine the difference between the damping ratio and stiffness of the numerical analysis. In addition, the damping effects are reviewed by comparing the difference in the damping ratio and stiffness of a test specimen filled with liquid 50% of the study. Results: Since the difference in resistance between a specimen with or without hollow core is 5%, it is judged that there is no structural problem, and the injection of liquid into the hollow core can increase the damping ratio, which can reduce noise or vibration. Conclusion: At less than 20% of hollow rate, there was little damping effect, and at 30%, damping effect was found. However, if liquid is injected into the hollow core of the specimen, damping rate is shown to increase, and the injection of liquid into the hollow part is believed to reduce noise or vibration.

강풍시 고층건물의 감쇠율과 고유진동수의 진폭의존성

윤성원 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

The wind tracker and structural monitoring system recorded wind and dynamic response data. The measured building is located in the mountain in Sokcho. The damping ration and natural frequency were analysed in this paper to obtain amplitude dependence. Amplitude dependent damping was showed clearly in the increasing rate of 9%. The tendency of dynamic properties of building obtained here are useful for the validation of dynamic properties of buildings in the evaluation of serviceability.

3층 철근콘크리트조 건물의 손상전후의 진동특성

윤성원,박용,지정환,임재휘,장동우 한국공간구조학회 2009 한국공간구조학회지 Vol.9 No.3

구조물이 건전한 상태에서 진동계측을 통한 고유진동수와 감쇠율과 같은 동적특성의 분석에 대하여 국내 외적으로 많은 연구가 진행되어 왔다. 그러나 실물 구조물에 대하여 파괴 직전까지의 큰 손상 후에 진동계측을 통한 동적특성에 대한 연구는 상대적으로 매우 미약한 실정이다. 따라서 본 연구는 3층 철근콘크리트조 건물에 엑츄에이터로 하중을 주어 건물에 손상을 준 후에 손상 전 후의 진동계측을 통하여 동적특성을 파악하였다. 손상 전 후에 대한 고유진동수 및 감쇠율을 산정하였으며, 이 결과를 국외의 기존 연구와 비교하였다. 상시진동계측 및 인력가진을 통한 계측방법을 실시하였으며, 계측 전에 고유치 해석을 선행하여 계측치와 비교분석을 하였다. 120mm의 수평변위를 준 결과 구조물의 파괴 직전 손상 전 후에 장변과 단변의 고유진동수는 각각 34.3%, 33.7% 감소하였고, 감쇠율은 각각 36.5%, 19.5% 감소하였다. 기존 국외의 연구결과와의 비교를 한 결과 고층형 건물보다 강성의 변화가 크게 감소됨을 확인할 수 있었으며, 저층형 구조물에 대한 안정성 검토가 시급함을 확인할 수 있다. Dynamic characteristics such as frequency and damping ratio in the ambient state of building has been progressed in domestic and foreign. However, there has not been any deep research of dynamic characteristics of full-scale structure using vibration measurement of the building damaged up to failure. Dynamic characteristics of three-story reinforced concrete building was evaluated before and after it was damaged by using a actuator. Dynamic characteristics is reviewed and compared with previous study. Ambient vibration and human excitation test were applied. After 120mm horizontal displacement by actuator, frequency of long and short direction is reduced to 34.3%, 33.7% and damping ratio is reduced to 36.5%, 19.5% respectively.

중공율과 감쇠율을 이용한 RC 중공 슬래브의 사용성 및 휨성능 평가

김종훈,김동백,김용곤,이재원,최정호 한국재난정보학회 2022 한국재난정보학회 논문집 Vol.18 No.4

연구목적: 철근콘크리트 중공 슬래브의 중공율에 따른 강성저하 및 감쇠율을 평가하여 그 성능을 분석하고, 중공체의 감쇠 효과와 중공율에 따른 강성저하가 슬래브의 사용성에 미치는 영향에 대한 연구를 수행하고자 한다. 연구방법: 슬래브의 중공율에 따른 진동영향을 평가하기 위하여 0.6m×0.21m×3.6m의 크기로 시험체를 제작하였으며, 중공율의 변화에 따른 강성과 감쇠의 변화율을 측정하기 위하여 중공률은 0.0%~30%까지 6단계로 설정하였다. 연구결과: 중공율이 증가하면 강성이 감소되므로 고유진동수도 감소하는 것으로 생각할 수 있으나 질량이 크게 감소하므로 고유진동수는 점진적으로 증가하며, 중공율 20%까지는 에너지 소산이 거의 일어나지 않으므로 층간소음 및 진동을 저감하기 위해서는 30% 정도의 중공율을 확보해야 한다. 결론: 중공율 이 30% 정도인 슬래브의 휨성능의 저하는 최소로 하되 적절한 고유진동수를 유지할 수 있으며 , 어느 정도의 감쇠증진 효과를 얻을 수 있는 것으로 나타났다.

능동질량형 제진장치의 제진성능 평가에 관한 연구

심학보(Shim Hak-Bo),이헌재(Lee Heon-Jae),정형조(Jung Hyung-Jo),박순전(Park Soon-Jeon),김상대(Kim Sang-Dae) 대한건축학회 2009 大韓建築學會論文集 : 構造系 Vol.25 No.2

This paper presents an application of the active mass damper (AMD) system to a high-rise building structure. The building has five basement floors with SRC structural system and 26 floors with steel structure system, and which makes inherent low damping ratio. To figure out the reason of the occupants’ discomfort, the preliminary field measurement was performed and additionally the wind tunnel test was carried out. The AMD system was selected to reduce the wind-induced vibration so that the serviceability of the building is assured. It is the first application of AMD for residential building in the country. Usually, the vibration control devices have been planned and implemented during construction stage. On the other hand, in this project the AMD system was implemented to the building in-use and this may be the first full-scale application of AMD to the existing building in the world. The two AMDs were implemented in June 2007 and the performance tests were also carried out. This paper mainly focuses on the performance test under the strong winds due to typhoon NARI in 2007.

초정밀장비 미진동제어를 위한 기계식 가변감쇠시스템의 진동제어성능 연구

심다솔(DaSol Shim),전종균(ChongKeun Chun),박용재(YongJai Park),박상곤(SangGon Park),한현희(HyenHee Han) 한국소음진동공학회 2017 한국소음진동공학회 논문집 Vol.27 No.4

The precision equipment for precision processing, manufacturing, and inspection process are usually managed in a strictly vibration-controlled environment that uses vibration isolators. To complement the weaknesses of these isolators, we designed and tested two types of mechanical adjustable dampers with helical gear: a box-like adjustable damper with a comb-type orifice and a round damper with a wing-type orifice. Additionally, we designed two versions for the latter: a standard version and an enhanced version to improve the variable performance. We then compared the performance of these two versions during their modal tests. Not surprisingly, the test showed that the enhanced version was superior to the standard version in variable damping. For this reason, we expect this damper to be particularly useful to semiconductor manufacturing facilities where the precision equipment are located.

H<SUB>∞</SUB> 제어알고리즘에 의한 능동형질량제진장치의 성능평가 연구

이헌재(Lee Heon-Jae),심학보(Shim Hak-Bo),정형조(Jung Hyung-Jo),박순전(Park Soon-Jeon),김상대(Kim Sang-Dae) 대한건축학회 2009 大韓建築學會論文集 : 構造系 Vol.25 No.4

This paper presents an application of the active mass damper (AMD) system to the high-rise building structure. The AMD system was installed at the top of the building already in use. The building has five basement floors with SRC structural system and 26 floors with steel structure system, and which makes inherent low damping ratio. The preliminary field measurement was performed and additionally the wind tunnel test was carried out. The H-infinity(H∞) control algorithm has been developed to utilize the maximum capacity of the AMD system. From the results of numerical simulation using the wind load obtained from the wind tunnel tests, it was found that the maximum acceleration responses of the building were reduced significantly. The acceleration responses at the top of the building in the controlled case measured under strong wind loads were compared with those in the uncontrolled case numerically simulated by using the wind load deduced from the measured data and a structural model of the building. It is demonstrated that the H-infinity control algorithm shows good control performance in reducing the building accelerations. This paper mainly focuses on the H-infinity control algorithm performance test of the building already in use under the strong winds due to typhoon NARI in 2007.

웨이브렛 변환 이용한 감쇠율 예측과 승용차 하쉬니스 평가에의 응용

이상권 한국소음진동공학회 1999 소음 진동 Vol.9 No.3

Estimation of damping ratio for vibration signals measured on the passenger car's sear is useful for the objective evaluation of impact harshness in car. The vibratio signal is a transient signal represented by many coupled modes of suspension system. Wavelet transform automatically decouples these modes in the time-frequency domain. Damping ratios for decoupled modes are obtained by logarithmic treatment for the Wavelet transformed signal. The objective evaluation using Wavelet transform has been well corresponded with subjective evaluation done by skilled engineers.

[Original] Experimental Study on the Damping Characteristics of a Cylindrical Structure Containing Oil and Bearing Balls

Bong Jo Ryu(류봉조),Seon Ho Song(송선호) 한국소음진동공학회 1996 소음 진동 Vol.6 No.1

건물의 상시진동과 인력가진에 의한 동적특성 계측 비교

장영주(Jang Young-Ju),박제우(Park Je-Woo),이지훈(Lee Jee-Hoon),김홍진(Kim Hong-Jin) 대한건축학회 2009 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.29 No.1(구조계)

This paper is concerned with comparisons of dynamic property by transient vibration and synchronized human excitation. Dynamic property including damping ratio and natural frequency is very important data of stability and usability of building. To obtain the reliability data, experiments were conducted to six buildings ranging from four to twelve stories. Dynamic property was analyzed by measuring transient vibration and synchronized human excitation using natural frequency of building. The synchronized human excitation measurement is finding dynamic property from obtained through free vibration wave after sympathy by human excitation using natural frequency of building. From the analyzed results, synchronized human excitation was more reliable data than transient vibration measurement about first mode.