• 제목/요약/키워드: seismic applicability

검색결과 238건 처리시간 0.026초

구조단열패널의 저에너지주택 적용을 위한 내화 및 단열성능 평가 (Fire Resistance Performance and Thermal Performance Evaluation of Structural Insulated Panels for Low-Energy Houses)

  • 이현주;나환선;이철희;최성모
    • 복합신소재구조학회 논문집
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    • 제3권2호
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    • pp.36-46
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    • 2012
  • Structure Insulated Panel (SIP) is an wooden structure material with which structure and insulation functions are satisfied. Hence, it would be a cost-effective model to implement low energy house which has higher insulation and structure performance and which the wall thickness is able to be reduced. In this study, performance of thermal insulation and fire resistance were evaluated in order to verify applicability to low energy house. Fire resistance test is performed on vertical load bearing members for partitions, and the test results satisfy one hour of fire resistance condition according to KS F 2257. The members include two layers of fireproof gypsum board with thicknesses of 12.5mm attached to SIP. Thermal insulation performance is satisfied with the 2012 standard ($0.225W/m^2{\cdot}K$). As the performance of resistance and thermal insulation are satisfied, SIP is expected to be applied to low energy building materials. In the future, the structural safety will be confirmed by structural performance and seismic performance test and the guidelines for distribution will be drawn up.

벤더 엘리멘트를 이용한 토목재료의 강성측정에 대한 적용성 연구 (A Pilot Study of Bender Elements in Stiffness Measurements of Civil Engineering Materials)

  • 목영진;정재우;장인성
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.308-319
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    • 2005
  • Piezo-ceramics are special materials which transform energy between mechanical and electrical forms. Bender-elements are composite materials consisting of thin piezo-ceramics and elastic shims, and are widely used as actuators and transducers in the field of electronics, robotics, autos and mechatronics utilizing the effectiveness of energy transformation capability. In geotechnical engineering, commercial bender-elements are used in laboratory as source and receiver in the measurements of soil stiffness. The elements were built by using various metal shims sandwiched between piezo-ceramics and coating over the composite in the research. A pair of elements were buried in a concrete block and used as source and receiver to measure the stiffness of the concrete. The test results were verified by comparing with the resonant column testing results. In a preliminary stage of the development of an in-situ seismic testing equipment using bender-elements for soft clay materials, shear waves were generated and measured by burying the elements in the barrel of kaolinite and water mixture. The measured shear wave signals were so distinct for the first-arrival pick that applicability of the elements in the field measurements is very promising.

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Efficacy of pushover analysis methodologies: A critical evaluation

  • Dutta, Sekhar Chandra;Chakroborty, Suvonkar;Raychaudhuri, Anusrita
    • Structural Engineering and Mechanics
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    • 제31권3호
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    • pp.265-276
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    • 2009
  • Various Pushover analysis methodologies have evolved as an easy as well as designers-friendly alternative of nonlinear dynamic analysis for estimation of the inelastic demands of structures under seismic loading for performance based design. In fact, the established nonlinear dynamic analysis to assess the same, demands considerable analytical and computational background and rigor as well as intuitive insight into inelastic behavior for judging suitability of the results and its interpretation and hence may not be used in design office for frequent practice. In this context, the simple and viable alternative of Pushover analysis methodologies can be accepted if its efficacy is thoroughly judged over all possible varieties of the problems. Though this burning issue has invited some research efforts in this direction, still a complete picture evolving very clear guidelines for use of these alternate methodologies require much more detailed studies, providing idea about how the accuracy is influenced due to various combinations of basic parameters regulating inelastic dynamic response of the structures. The limited study presented in the paper aims to achieve this end to the extent possible. The study intends to identify the range of applicability of the technique and compares the efficacy of various alternative Pushover analysis schemes to general class of problems. Thus, the paper may prove useful in judicial use of Pushover analysis methodologies for performance based design with reasonable accuracy and relative ease.

HWAW(Harmonic Wavelet Analysis of Wave) 방법을 이용한 새로운 탄성파 지반조사기법의 현장 적용 (Field Application of New Seismic Site Characterization Using HWAW(Harmonic Wavelet Analysis of Wave) Method)

  • 박형춘;김동수;이병식
    • 한국지반공학회논문집
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    • 제20권6호
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    • pp.51-59
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    • 2004
  • 공학적 물성치로서의 저변형율에서의 전단탄성계수의 결정은 다양한 토목분야에서 매우 중요하다. 본 논문에서는 저변형율에서의 전단탄성계수를 결정하기 위하여 개발된 HWAW(Harmonic Wavelet Analysis of Wave)방법을 이용한 지반조사기법의 실제 현장에서의 타당성을 검증하기 위하여 두 곳의 현장에 HWAW방법을 적용하였다. HWAW방법을 검증하기 위하여 동일한 현장에서 수행된 SASW시험과 PS-Suspension Logging 실험의 결과와 비교하였다. 이를 통하여 HWAW방법이 배경잡음과 지반의 횡방향 불균일성에 의한 오류를 기존 방법에 비하여 최소화 할 수 있으며, 국부적이며 정밀한 대상지반의 실제 전단파 속도 주상도를 매우 효과적으로 결정할 수 있음을 확인할 수 있었다.

SKY-BRIDGE로 연결된 건물의 진동제어 (Vibration Control of Buildings Connected by a Sky-Bridge)

  • 류진국;김진구
    • 한국전산구조공학회논문집
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    • 제17권2호
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    • pp.203-213
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    • 2004
  • 본 연구에서는 최상층에 설치된 연결교량과 두 건물의 연결부에 점탄성감쇠기 (Viscoelastic Dampers, VED)를 설치하여 지진에 의한 연결된 건물의 응답을 저감하는 방법에 대해서 연구하였다. 제안된 방법의 적용성을 백작잡음하중에 대한 2자유도계 구조물의 RMS (root-mean-squared) 응답을 통하여 검토한 후, 점탄성감쇠기의 크기변화에 따른 응답 감소 효과를 분석하기 위해 다양한 층수의 연결된 구조물에 대하여 지진응답 해석을 수행하고, VED 설치 전후의 최대변위, 소성힌지 분포, 잔류변위 등을 비교하였다. 해석결과에 따르면, 구조물의 응답을 최소화하는 점탄성감최기의 적정 크기가 존재하며, 연결된 두 구조물의 고유주기의 차이가 증가할수록 점탄성감쇠기의 진동제어 효과가 커진다는 것을 알 수 있다.

탄성파 굴절법 토모그래피를 이용한 지반의 속도분포 해석 (Interpretation on the Subsurface Velocity Structure by Seismic Refraction Tomography)

  • 조창수;이희일;서정희
    • 지구물리와물리탐사
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    • 제5권1호
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    • pp.6-17
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    • 2002
  • 지형기복에 적용할 수 있는 굴절법 토모그래피법을 개발 및 적용하여 자료해석에 용이성을 주고자하였다. 굴절법 토모그래피의 적용에 있어서 중요한 요소인 측선길이 및 배치, 수신점과 송신점 간격 및 배치, 지형기복 여부를 살펴 보기 위하여 모형자료에 대한 결과를 살펴보았다. 또한 하부의 저속도 층의 규명을 위하여 VSP자료와 동시역산을 수행한 결과 시추공 주변의 저속도 층을 구별할 수 있었다. 택지개발 지역의 탐사 자료에 토모그래피법의 적용한 결과 두 측선에서 얻어진 속도구조의 연속성이 좋았고 또한 속도분포에 대하여 정량적으로 굴삭난이도를 평가하여 공학적으로 이용하고자 하였다.

An equivalent linearization method for nonlinear systems under nonstationary random excitations using orthogonal functions

  • Younespour, Amir;Cheng, Shaohong;Ghaffarzadeh, Hosein
    • Structural Engineering and Mechanics
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    • 제66권1호
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    • pp.139-149
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    • 2018
  • Many practical engineering problems are associated with nonlinear systems subjected to nonstationary random excitations. Equivalent linearization methods are commonly used to seek for approximate solutions to this kind of problems. Compared to various approaches developed in the frequency and mixed time-frequency domains, though directly solving the system equation of motion in the time domain would improve computation efficiency, only limited studies are available. Considering the fact that the orthogonal functions have been widely used to effectively improve the accuracy of the approximated responses and reduce the computational cost in various engineering applications, an orthogonal-function-based equivalent linearization method in the time domain has been proposed in the current paper for nonlinear systems subjected to nonstationary random excitations. In the numerical examples, the proposed approach is applied to a SDOF system with a set-up spring and a SDOF Duffing oscillator subjected to stationary and nonstationary excitations. In addition, its applicability to nonlinear MDOF systems is examined by a 3DOF Duffing system subjected to nonstationary excitation. Results show that the proposed method can accurately predict the nonlinear system response and the formulation of the proposed approach allows it to be capable of handling any general type of nonstationary random excitations, such as the seismic load.

토목공학 분야에서의 충격반향법의 응용 (Application of Impact Echo Method to Civil Engineering Fields)

  • 정연문;하희상
    • 지구물리와물리탐사
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    • 제3권3호
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    • pp.94-100
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    • 2000
  • 금속 물체의 내부 상태를 조사하기 위하여 사용되고 있는 여러 가지 비파괴 조사법들은 콘크리트 재료의 불균질성으로 인하여 콘크리트 물체에의 적용에는 한계가 있다 충격반향법은 물성의 변화가 존재하는 경계면이나 결함 부위에서 반사되는 탄성파의 공진 주파수를 이용하는 비파괴 조사법으로서 콘크리트 구조물의 내부 상태를 파악하기 위하여 활용될 수 있다. 본 연구에서는 충격반향법의 현장 적용을 위한 자료획득 시스템을 구축하였고 여러 가지 조건하에서 현장 시험을 수행하였다. 콘크리트 구조물의 두께 및 결함, 공동 존재 여부, 옹벽 뒷채움 상태와 터널 라이닝의 두께 및 결함, 그리고 활주로의 포장 두께 및 결함등의 조사를 위하여 충격반향법을 적용하였다. $10\%$ 이하의 오차 범위내에서 결과를 제공함으로써 충격반향법의 토목분야에서의 활용 가능성이 입증되었다.

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복합폴리우레아를 도포한 콘크리트 구조물의 구조성능 개선에 관한 실험적 연구 (An Experimental Study on the Improvement of Structural Performance for Concrete Structure Spraying Composite Polyurea)

  • 조동호;김진봉;김태완;은희창
    • 대한건축학회논문집:구조계
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    • 제35권1호
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    • pp.21-28
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    • 2019
  • This study investigates the applicability of composite polyurea to contain fiber reinforcement like fiber glass, steel fiber and carbon nanotube. Polyurea as elastomer is an excellent water-proofing material with many mechanical characteristics such as high tensile strength, ductility, high rate of expansion and contraction, and so on. The reinforcing fibers can be utilized for improving the load-carrying capacity of concrete structures. The polyurea plays a role to improve the ductility and toughness. Composite polyurea takes the mechanical advantages of the fibers and the polyurea. The test variables include the type of reinforcing fiber, its spraying thickness, and its weight ratio contained in the composite polyurea. It is observed that the load-carrying capacity, and the ductility and toughness are improved with the increase in the spraying thickness and the weight ratio contained in the composite polyurea. It is expected that the composite polyurea can be widely utilized in enhancing the structural and seismic performance.

공업용 플라스틱의 선조립형 비좌굴가새로 보강한 건축물의 내진 성능 평가 (Seismic Performance Evaluation of Structure Reinforced with Precast-Buckling Restrained Brace of Engineering Plastics)

  • 김유성;박병태;이준호
    • 한국공간구조학회논문집
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    • 제21권4호
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    • pp.31-38
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    • 2021
  • 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.