• Title/Summary/Keyword: 구조용 발포재

Search Result 7, Processing Time 0.018 seconds

Design of Lightweight Fill Method on Soft Ground using Expanded Polystyrene (연약지반상 스치로폴 경량성토공법의 설계)

  • 유기송
    • Journal of the Korean Professional Engineers Association
    • /
    • v.27 no.5
    • /
    • pp.39-45
    • /
    • 1994
  • 스치로폴은 발포폴리스티렌(EPS : Expanded Poly-Styrene)을 말하며, 이것은 스티렌모노머(Stone Monomer)를 중합하여 만든 플리스티렌과 여기에 첨가한 발포제가 주원료로 되어 있다. 폴리스티렌은 1930년대에 미국과 독일에서 공업화되었고 스치로폴은 1943년 초에 미국에서 공업화가 이루어져 건물의 단열재, 물품포장재 등으로 이용되어 왔다. 1972년에는 노르웨이에서 연약지반상 교량의 접속도로 보수공사에 처음 스치로폴 성토공법이 이용되어 교대의 측방유동 방지대책으로 성공을 거둠에 따라 연약지반상의 경량성 토재 및 토압을 받는 옹벽, 교대 등 구조물의 경량 뒷채움재로서 각광을 받게 되었다. 한편 우리나라에서는 1994. 6월에 한국지반 공학회 주최로 개최된 "발포폴리스티렌(EPS) 이용 성토공법 국제심포지엄"에서 양산-구포간 고속도로성토(L=70m) 및 서해안고속도로의 교대 뒷채움에 스치로폴 경량성토재가 이용된 문헌이 발표된 바 있으며, 시중에서 단열재용으로 판매되고 있는 스티로폴 평판의 규격은 표 1과 같다. 스치로폴은 그 가격이 비싼 편이지만 단위중량(20-40kgf/m$^3$)이 흑의 50/1-100/1 밖에 안되는 초경량재로서 강도, 내구성 및 시공성이 우수한 성토용 신재료이기 때문에 연약지반상에서 구조물 시공시 지반의 과대한 침하, 측방유동 및 사면활동 등이 생길 경우 도로성 토재 또는 교대, 옹벽 등 구조물의 뒷채움재로서 스치로폴을 사용하면 이를 방지할 수 있으므로 매우 효과적인 토목자재라 할 수 있다. 따라서 본고에서는 지금까지의 연구결과, 시험시공 및 시공실적 등을 토대로 발표된 참고문헌을 중심으로 연약지반상 스치로폴 성토공법의 설계방법에 대하여 간단히 소개하고자 한다. 소개하고자 한다.

  • PDF

Investigation of Compressive Strength and Foaming Characteristics of Acid Anhydride Epoxy Foam by Foaming Agent (발포제에 따른 산무수물계 에폭시 폼의 압축강도 및 포밍특성 분석)

  • Kwon, Dong-Jun;Kim, Jong-Hyun;Park, Sung-Min;Kwon, Il-Jun;Park, Joung-Man
    • Composites Research
    • /
    • v.31 no.4
    • /
    • pp.133-138
    • /
    • 2018
  • Polymer foams were used to fill the void in the structure in addition to flame retardant and heat insulation. Polymer foams such as polyurethane, polyisocyanurate, poly(vinyl chloride), polyethylene terephthalate were used to weight lighting materials. In this study, epoxy foam was used to improve mechanical properties of polymer foam. Acid anhydride type hardener reacts with polyol. Using this phenomenon, if blowing agent was added into epoxy resin using acid anhydride type hardener, formation and compressive properties of epoxy foam was studied. Formation of polymer foam was compared with type of blowing agent and concentration of blowing agent via compressive test. As these results, optimized condition of epoxy foam was found and epoxy foam had better compressive property than other polymer foam.

Crashworthiness Design Concepts for the Improved Energy Absorbing Performance of an Aluminum Lightweight Vehicle Body (알루미늄 경량 차체의 충돌에너지 흡수 성능 향상을 위한 설계 개선 연구)

  • 김범진;허승진
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.11 no.3
    • /
    • pp.155-160
    • /
    • 2003
  • For the weight reduction of vehicle body up to 20∼30% compared to the conventional monocoque steel body·.in-white, most automotive manufacturers have attempted to develop the aluminum intensive body-in-white using an aluminum space frame. In this paper, the crush tests and simulations for the aluminum extrusions filled with the structural from are performed to evaluate the collapse characteristics of that light weighted material. From these studies. the effectiveness of structural for is evaluated in improving automotive crashworthiness. In order to improve the improve energy absorption capability of the aluminum space frame body, safety design modifications are performed and analyzed based on the suggested collapse initiator concepts and on the application of the aluminum extrusions filled with structural foam. The effectiveness of these design concepts on the frontal and side impact characteristics of the aluminum intensive vehicle structure is investigated and summarized.

Mechanical Characteristics Analysis of Structural Light-weight Aluminum Foam (구조용 경량 알루미늄 발포금속의 기계적 특성 연구 분석)

  • Ma, Jeong Beom;Lee, Jeong Ick
    • Journal of the Korea Convergence Society
    • /
    • v.2 no.3
    • /
    • pp.1-6
    • /
    • 2011
  • Aluminum foam is one of the representative light-weight materials. In this study we analyzed the mechanical properties of the aluminum foam structures. Aluminum materials with pores have novel mechanical characteristics such as flame retardancy, damping, and energy absorption which are superior to those of polymer foam. Furthermore its reusable properties draw considerable interests. General properties, energy and acoustic absorption will be investigated and future research issues such as binding techniques of foam materials with other structures will be discussed through foam application examples.

An optimal mix design of sound absorbing block on concrete ballast in urban train tunnel (도시철도 터널내 콘크리트 도상용 흡음블럭의 최적 배합설계)

  • Lee, Hong-Joo;Oh, Soon-Taek;Lee, Dong-Jun
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.18 no.1
    • /
    • pp.75-82
    • /
    • 2016
  • As spreading of train concrete ballast leads to the increase resounding friction noise, an porous sound absorbing block is applied in urban train tunnel as a counterparts against the friction noise. Three steps of major variables tests for an optimal mix design of the block are conducted to pursue the light weight of the block. Pilot property tests of the block for the cases of the fly-ash only as lightweight aggregates are carried satisfying KRT(Korean Rail Transit) and new KRS(Korean Railway Standards). Based on the results of pilot tests, required structural strength and admixture effects are evaluated. Additionally, typical lightweight aggregates are replaced so that lightweight and strength are improved for serviceability of poor working conditions and proper maintenance in urban train tunnel.

Research on the Load Reduction Effect Using EPS (EPS의 압축성을 이용한 토압저감효과에 관한 연구)

  • 김진만;조삼덕;최봉혁;오세용
    • Journal of the Korean Geotechnical Society
    • /
    • v.20 no.1
    • /
    • pp.101-108
    • /
    • 2004
  • For the last 30 years, the use of EPS as a lightweight filling material has grown significantly throughout the world. The fields of applying EPS block have also increased. The most representative example in geotechnical applications is using EPS block as a compressible inclusion that causes the reduction of static earth pressure on earth-retaining wall, bridge abutment and pipes. EPS blocks have a good workability by its lightweight characteristic and a uniform engineering property with the change of its density. Also EPS blocks have best material property as a compressible inclusion. This paper analyzes that the compressible inclusion function of EPS causes the reduction of static earth pressure on retaining wall and concrete box culvert. A series of in-situ tests were conducted to evaluate the reduction of static earth pressure using EPS inclusion. Based on in-situ test, it is found that the magnitude of static earth pressure was reduced to about 20% for the retaining wall and about 45∼53% for the box culvert compared with theoretical active earth pressure.

Fundamental study on sound absorption of a dental hand piece using micro-porous EPP substrate processed by UV laser (UV 레이저응용 마이크로 다공성 EPP 기판의 치과용 핸드피스 흡음성능에 관한 기초연구)

  • You, Dong-Bin;Shin, Myung-Ho;Byun, Hyo-Jin;Choi, Do-Jung;Sung, Kuo-Won;Ma, Yong-Won;Shin, Bo-Sung
    • Journal of Convergence for Information Technology
    • /
    • v.9 no.5
    • /
    • pp.158-164
    • /
    • 2019
  • Recently many studies to reduce the noise of dental hand piece which generate inevitably mechanical sound to offend to the ear of a patient have been spotlighted. Generally, methods of adding a sound absorbing material inside the exhaust valve, air pump of machine or automobile are widely reported as optimal way to reduce the mechanical noise. In this paper we studied a new UV laser aided manufacturing of micro-porous structure of EPP substrate and applied dental hand piece to improve the efficiency of sound absorption. A lot of micro-sized pores were fabricated with UV laser processing on the surface of sliced EPP substrate. From fundamental experiments, more high-performance of micro-porous EPP substrate has finally demonstrated for sound-absorbing structure of the micro muffler inside dental hand piece, which actually has the excellent potential to apply a lot of potable machine.