• 제목/요약/키워드: layer constructions

검색결과 36건 처리시간 0.025초

파일직경과 기초하부 토사층의 점착특성에 따른 마이크로파일 보강효과 (Reinforcing Effect of Micropiles According to the Cohesive Characteristics of the Soil Layer Beneath Foundations)

  • 장창환;김무연;황태현
    • 한국지반공학회논문집
    • /
    • 제40권2호
    • /
    • pp.41-53
    • /
    • 2024
  • 마이크로파일은 직경 300mm이하인 소구경 현장타설말뚝을 칭하며, 기존 구조물의 보강과 신축 구조물의 지지 목적으로 주로 활용되어 왔다. 또한 파일의 활용이 증가함에 따라 마이크로파일 또는 마이크로파일-레프트의 지지특성에 대한 연구가 활발히 진행되어왔으며, 연구결과를 통해 기초에 대한 파일 보강효과가 입증되었다. 그러나 대부분 기존 연구는 마이크로파일-레프트가 파일조건에 따라 기존 파일-레프트와 다른 거동을 보일 수 있고, 기초에 대한 파일의 보강효과가 기초하부 토사층의 점착특성에 따라 좌우될 수 있음을 고려하지 않았다. 따라서 본 연구에서는 수치해석을 통해 파일조건과 기초하부 토사층의 점착특성에 따른 마이크로파일의 보강효과를 평가하기 위해 3차원 수치해석을 수행하였다. 연구결과, 비 점착특성을 가진 토사층 조건에서의 기초에 대한 마이크로파일의 보강효과가 점착력을 가진 토사층인 경우보다 좀 더 효과적이고, 최대 마이크로파일의 보강효과는 전면기초의 지지력보다 3.7배 정도 증가시킬 수 있는 것으로 나타났다.

스트랜드/파티클 복합체의 기계적 성질에 관한 연구(I) - 단면구성이 기초물성에 미치는 영향 - (A Study on Mechanical Properties of Strand/Particle Composites(I) - Effect of Layer Constructions -)

  • 김유정;시부사와 타츠야
    • Journal of the Korean Wood Science and Technology
    • /
    • 제28권3호
    • /
    • pp.1-8
    • /
    • 2000
  • 본 연구는 미이용 자원인 소경목(小經木) 조생수(早生樹) 등의 저질원료로부터 고성능을 지니는 구조용 보드를 제조하는 기술을 개발하는 것을 목적으로 하여 할렬 스트랜드 (S)/파티클(P) 복합체의 층구조와 S와 P의 혼합비율을 바꾼 단면구성에 따른 기초적 물성을 검토했다. 그 결과 스트랜드층을 포함하고 있는 SP 복합체의 경우, 전체적으로 휨성능(MOR, MOE)이 매우 높았다. 또 S단층 보드는 현저한 이방성을 나타내었지만 층구조가 PB에 가까워질수록 이방성은 감소하여, 7층 구조의 복합체는 이방성이 적었으며 특히 SP7은 직교방향도 휨강도가 높았다. 습윤시 휨강도 성능도 같은 경향을 나타내었다. 박리강도(IB)는 PB가 가장 높았고, 스트랜드층을 가진 복합체는 거의 같은 값을 나타내었다. 두께팽창율(TS) 은 PB가 가장 적은 값을 나타내었으며, 표층이 P층인 구조가 S표층구조보다 적은 경향을 나타내었다. 복합체의 표면특성은 표층 엘리먼트의 영향을 받아, 적고 미세한 엘리먼트인 P표층의 복합체가 크고 두꺼운 S표층 복합체보다 양호하였다. S와 P의 혼합비율의 영향은, SP비(比)를 증가시켜도 강도물성(MOR, MOE, IB)은 향상되지 않으며, 오히려 저하되는 것도 있었다. 두께팽창율(TS)은 SP 비(比) 1:1 이상의 복합체에서는 S만으로 제조한 보드와 같은 정도의 값을 나타내었다.

  • PDF

고주파 부분방전 측정에 의한 초고압 접속함 신뢰성 평가 기술 (A Evaluation Technique for Reliability of Extra-High Voltage Cable Accessories using High Frequency Partial Discharge Measurement)

  • 신두성;이창영;김충식;전승익;김동욱;박완기
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제49권3호
    • /
    • pp.186-195
    • /
    • 2000
  • In this paper, partial discharge (PD) measurement was performed to evaluate the quality of the cable joint and termination constructions. The resistive coupling technique for PD detection using resistivity of semiconducting layer of the cable in the accessories, such as joints and terminations. With high frequency PD (HEPD) measurement, an excellent sensitivity below 20pC could be achieved under unshielded condition. The localization of the defects in the accessories could be identified. During heating cycle, PDs were monitored and analyzed. At that time, the PDs were dependent on the temperature of the heating cycle and showed cyclic behaviors, which were attributed to local delamination of the interfaces, between epoxy unit and stress relief cone(SRC) and between SRC and cable, due to the difference of thermal expansion. As a conclusion, HFPD measurement technique was proven to be an effective diagnostic method for qualification of extra high voltage (EHV) cable accessories. With this technique, the optimal design of the components of the accessories could be verified not only in an early stage but also under operating condition. This technique would result in the improvement of the reliability of the EHV cable accessories.

  • PDF

해안매립지반에서의 토류가시설 시험시공 및 변경사례 (A Field Case on the Pilot Constructions and Changes of a Braced Cut Wall in a Coastal Filled Land)

  • 황영철;김기림;김연정
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2006년도 추계 학술발표회
    • /
    • pp.46-55
    • /
    • 2006
  • There are many kinds of braced cut wall methods as the sheet pile, SCW, CIP and slurry wall which is adoptable for a deep excavation construction in a coastal filled land. The braced cut wall which has a strong stiffness is very stable but it has the weak point that the construction cost is high. Thus when a braced cut wall is designed, the geotechnical engineers choose the braced cut wall which has more safe and economic in the consideration of surrounding buildings near the construction site. Especially, when the sheet pile method as a braced cut wall is cheesed, the layer order and consistence of a coastal deposit stratum are considered and the pile driving method is also considered. This paper introduces the case that the originally box-type sheet pile wall was changed to U-type and high strength material after the pilot test at the subway construction site in a coastal filled land. This paper also introduces the case that the sheet pile's driving method was changed to special method in the section of the temporary coffer dam which had made when the present coastal filled land was formed.

  • PDF

다층 인식자 신경망 모형을 이용한 FRP 판의 부착강도 예측 모형 개발 (Development of Bond Strength Model for FRP-Plates Using Multi-layer Perceptron)

  • 곽계환;석인수;황해성;성배경;장화섭
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
    • /
    • pp.1009-1014
    • /
    • 2006
  • Synthetic materials with excellent thermodynamic characteristics and the merit of anti-corrosion are frequently used in buildings and constructions for enforcement of bent in stead of steel plates. Among them, many practical studies have been conducted on bond strength because of increased bond strength of FRP plates. Previous investigators identified the bond strength of FRP plates through experiments with settlement of various variables to identify the bond strength. However, the experiments to identify the bond force are difficult to be conducted because they requires large expenses and long time for equipment arrangement, thus, are conducted with limitation. In this study, for bond experiment, optimum neural network model was developed with use of Back-propagation and Conjugate gradient technique of previous investigators. Learning was performed with use of the variables of previous investigators in developed neural network model so as to identify the bond strength of FRP plates. for verification of developed model, credibility and excellence was proven by comparing with the models of previous investigators.

  • PDF

An English Tough-construction Resolution: A Minimalist Account

  • Hong, Sung-Shim
    • 한국언어정보학회지:언어와정보
    • /
    • 제13권1호
    • /
    • pp.127-143
    • /
    • 2009
  • Tough-construction is, undoubtedly, one of the most puzzling syntactic problems in the history of transformational grammar. Various approaches have been proposed including Deletion approaches (Akmajian, 1972; Lasnik and Fiengo, 1974) and movement approaches. Among the movement approaches, Chomsky (1977; 1981) argues for movement of null Operator, and Hornstein (2001) argues for a two-step movement equipped with Sideward movement. Most recently, Schueler (2004) and Hartman (2009) each have also argued for a kind of movement approach. With the development of the Minimalist syntax (Chomsky, 1995; Chomsky, 2000; Chomsky, 2001), tough-construction, an age old problem in the description of grammar, turns into another round toward to a more satisfactory answer. By examining the most recent competing analyses of tough-constructions, this paper defends and extends Schueler's (2004) analysis, rather than Hartman's (2009) two step movement approach. Furthermore, this paper proposes that tough-subject originates from the intermediate CP internal Spec-TopicP position rather than from the iterated CP layer (Authier, 1992). This approach has more descriptive power than it was originally argued for in Schueler (2004) and is a step closer toward Minimalism insofar as the conception of government is no longer utilized.

  • PDF

복층건물의 출입문 개방여부에 따른 화재온도분포 및 독성가스 농도 변화특성에 관한 연구 (A Study on Characteristics of Fire Temperature and Concentration of Toxic Gases while the Door Opening or Closed on Multi-layered Construction)

  • 이정윤;김정훈;김응식;김홍
    • 한국안전학회지
    • /
    • 제32권2호
    • /
    • pp.72-77
    • /
    • 2017
  • In S. Korea, recently, building fire accidents of residential accommodations or recreational facilities have taken place more frequently than before. Among various building constructions, Multi-layered structure, such as office-residential complex, are mostly made in S. korea. $O_2$, $CO_2$, CO, $NO_x$, $SO_x$, and HCl, these gases has toxic hazard and harmful for human body. And it is predicted that different concentration of released gases from diesel pool fire with upper and lower layer. Therefore, this study reports the fire characteristics of Multi-layered structure by analyzing the fire behavior and concentration of combustion gases of a experimental compartment via real scale fire experiment, in order to predict risks and secure safety for similar fire accidents.

다중반사 구조를 갖는 복합구조물의 RCS 감소를 위한 광대역 다층 전파흡수체 설계 (Broad-band Multi-layered Radar Absorbing Material Design for Radar Cross Section Reduction of Complex Targets Consisting of Multiple Reflection Structures)

  • 김국현;조대승;김진형
    • 대한조선학회논문집
    • /
    • 제44권4호
    • /
    • pp.445-450
    • /
    • 2007
  • An optimum design process of the broad-band multi-layered radar absorbing material, using genetic algorithm, is established for the radar cross section reduction of a complex target, which consists of multiple reflection structures, such as surface warships. It follows the successive process of radar cross section analysis, scattering center analysis, radar absorbing material design, and reanalysis of radar cross section after applying the radar absorbing material. It is demonstrated that it is very effective even in the optimum design of the multi-layer radar absorbing material. This results from the fact that the three factors, i.e.. the incident angle range, broad-band frequencies, and maximum thickness can be simultaneously taken into account by adopting the genetic algorithm.

조선시대 관영건축의 벽체에 사용된 중깃(中衿)과 외엮기 기법에 대한 연구 (A Study on the Method of Oeyeokki and Joongkit in Earth Wall of Government Constructions in the period of Chosun Dynasty)

  • 이승환;장헌덕
    • 건축역사연구
    • /
    • 제28권4호
    • /
    • pp.27-36
    • /
    • 2019
  • The traditional earth wall structure consists of a Joongkit(a small reinforcing post inside a wall) and a Oe(a miscellaneous tree, rendered laths) based on the space between the columns and applying the soil. The members who act as the base layer before applying soil used joongkit, sakmok, and oemok, which are known to correspond to the current joongkit, gasisae, and lath strips. This study was designed to understand the following through an analysis of the ancient texts, such as uigwe. Through a study on the usage and specifications of joongkit recorded on the uigwe, I wanted to reveal that joongkit is a material that has different specifications, functions, and installation techniques from current joongkit. The purpose of this study was to present the differences and technical features of the components of use for two types of oeyeokki technique of traditional wall. In addition, the items to be considered at the actual cultural heritage repair site were reviewed in the restoration of the earth wall weaving technique.

대심도 해저 연약점토의 압축지수(Cc) 특성에 관한 연구 (A Characteristic Study of Compression Index(Cc) of the Deep Seabed Soft-Clay)

  • 홍순택;이승호
    • 한국지반환경공학회 논문집
    • /
    • 제12권5호
    • /
    • pp.21-28
    • /
    • 2011
  • 연약지반의 효율적이고 경제적인 설계와 시공을 위하여 사전에 물리적, 역학적 특성을 상세히 파악하는 것이 중요하다. 본 연구는 대심도 해저지층의 연약점토에 대하여 함수비, 초기간극비, 액 소성한계, 압축지수 등의 물리적 역학적 특성을 파악하고 토질정수간의 상관성을 규명하여 국내 외 학자들이 발표한 식과 비교 분석하였다. 또한 이를 비교하여 높은 상관성을 가질 수 있는 대표적인 관계식을 산정하였다.