• Title/Summary/Keyword: High Temperature (Fire)

Search Result 770, Processing Time 0.033 seconds

A Study on the Post-buckling Behaviour of Single-layer Domes exposed to Fire (화재에 노출된 단층 돔의 후좌굴 거동에 관한 연구)

  • Lee, Sang-Jin;Bae, Jungeun
    • Journal of the Architectural Institute of Korea Structure & Construction
    • /
    • v.35 no.8
    • /
    • pp.139-148
    • /
    • 2019
  • The lightweight structures such as domes are particularly vulnerable when it has been subjected to high temperature induced by the fire. It is therefore crucial to predict the possible instability path of structures exposed to the fire in structural design process. In this study, the instabilities of single-layer domes is investigated by using finite element technologies with the consideration of high temperature. The material properties of members under high temperature are considered by using the reduction factors which is provided in Eurocodes 3. Some damage patterns are assumed with use of a structural unit which is symmetric in radial direction. For numerical evaluations, the geometrically nonlinear truss element is implemented and the arch-length control method is employed to trace the post-buckling behaviour of domes. From numerical results, it is found to be that a significant change of post-buckling behaviour is detected in dome structures when structural members are exposed to the fire.

An Analytic Method for the Residual Strength Evaluation of Fire-Damaged Reinforced Concrete Beam

  • Park, Won-jun;Park, Ki-bong;Lee, Han-seung
    • Architectural research
    • /
    • v.10 no.2
    • /
    • pp.37-42
    • /
    • 2008
  • This study is to get the proper evaluation of the residual property of reinforced concrete beam exposed to fire. This study focused on the strength resistance and analytical evaluation of RC members exposed high temperature. And this study is the basis analytical research to conduct the other studies. To analysis by the finite element method, the Total-RC program was used to analysis it and the Total-Temp program was also used to analysis the temperature distributions at the section. All of results were compared with the pre-existing experimental data of simple supported beam. Using it, the parameters influencing the structural capacity of the high temperature-damaged RC members and residual strength estimation are investigated. The temperature distribution and the structural capacity at the section are calculated in this step. An application of this method is compared with the heating test result and residual property test for simple supported beam which is subjected to ISO 834 test fire. The results of this study are as follows; 1) The loads-displacement relationship of RC beam, considering initial thermal stress of cross section and heat transfer analysis are estimated comparing analytical value with pre-existing experimental results. 2) by the heating time (0, 1, 2 hours), the results of analysis with parameters show that the load capacity exposing at fire is affected.

Synthetic Circumstantial Judgement System Applied Recognition of Fire Levels Model (화재 상황 인식 모델을 적용한 종합 상황 판단 시스템)

  • Song, Jae-Won;Lee, Se-Hee;An, Tae-Ki;Shin, Jeong-Ryol
    • Proceedings of the KSR Conference
    • /
    • 2011.05a
    • /
    • pp.1275-1281
    • /
    • 2011
  • This paper presents synthetic circumstantial judgement system that detects and predicts a fire in subway station. Unlike conventional fire surveillance systems that judge the fire or not through smoke, CO, temperature or variation of temperature, a proposed system discovers a fire more easily or gives the alarm high possibility of fire to operator through recognition of fire levels based on Fuzzy Inference System using by FCM and information of objects from video data.

  • PDF

Analytical Estimation of Internal Temperature of RC Beam under Fire (화재시 철근 콘크리트 보 내부 온도의 해석적 추정)

  • Lee Eun-ju;Shin Mi-kyung;Kang Ji-yeon;Shin Yeong-Soo
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.05a
    • /
    • pp.548-551
    • /
    • 2004
  • The main purpose of this study is to estimate the internal temperature of RC beam under fire. For this purpose, the finite difference method was used. In the previous studies, the structural behavior of fire damaged RC beams was investigated through experiments. The result was concluded that The high temperature affects the properties of concrete such as the elastic modulus, the compressive strength. The internal temperature Estimation of the concrete is helpful for understanding the structural behavior of fire damaged RC beams. Especially, high strength concrete has more spalling than normal strength one. So, this study is performed analysis of internal temperature of RC beam considering spalling.

  • PDF

Study of fire protection performance of newly developed cementitious fire protection material for application to architectural building (건축구조물에 적용하기위한 신개발 시멘트계 내화재료의 내화성능에 관한 연구)

  • Kim, Jang-Ho;Park, Hae-Geun;Lee, Myeong-Sub;Won, Jong-Pil;Lim, Yun-Mook;Lee, Kyong-Min
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2006.11a
    • /
    • pp.633-636
    • /
    • 2006
  • High-rise and large size buildings require high strength concrete and steel structure as a necessity. However, high strength concrete and steel structure are strong material but have a weakness to high temperature. Therefore, fire protection is a matter that must be considered very importantly in design for structure of high strength concrete and steel. Fire proof board that is existing method for fire proof has relatively low performance in fire protection emphasizes the need of new fire protection material due to the using of in numerable inflammables like plastics. The objective of this study is to understand the fire-resisting performance of newly developed fire protection material for building. This paper describes the results of fire tests using ISO curve that is fire protection regulation for buildings of the newly developed cementitious fire protection coating material applied concrete tunnel lining specimens.

  • PDF

State-of-the-Art Research and Experimental Assessment on Fire-Resistance Properties of High Strength Concrete (고강도 콘크리트의 내화 특성에 관한 기존연구 고찰 및 실험적 연구)

  • Kim, Woo-Suk;Kang, Thomas H.K.;Kim, Wha-Jung
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.18 no.3
    • /
    • pp.28-39
    • /
    • 2014
  • This paper reviews past literatures relevant to fire-resistance properties of high strength concrete and investigates spalling mechanism of high strength concrete in fire. First, literatures were reviewed on spalling occurrence and fire-resistance methods. Second, a chemical change of concrete components in an elevated temperature was presented. Finally, the mechanism of the spalling occurrence and spalling resistance were examined in terms of hybrid fiber content. The focus of the experimental study as part of this research is to investigate the effects of fire on the variation of thermal properties of high strength concrete, which tends to be used in super tall buildings. This experimental study was devised to investigate the fire-resistance performance of high strength concrete containing hybrid fibers. A total of 48 test specimens were exposed to high temperature ranging from $100^{\circ}C$ to $700^{\circ}C$, including room temperature (${\sim}20^{\circ}C$). Test results provide valuable information regarding fire-resistance properties of strength concrete with 100 MPa or greater.

Evaluation on the Mechanical Properties of Fire Resistant Steels at High Temperature Conditions with Manufacturing Processes (제조 방식에 따른 건축용 내화강재의 고온 시 기계적 특성 평가)

  • Kwon, In Kyu
    • Journal of Korean Society of Steel Construction
    • /
    • v.19 no.2
    • /
    • pp.181-190
    • /
    • 2007
  • A fire-resistant steel with enhanced load-bearing capacity has been developed to enable structural elements such as columns and beams withstand exposure to severe fire conditions. To precisely evaluate the fire-resistant performance of structural elements that compose fire-resistant steels, mechanical properties such as yield strength and elastic modulus are essential. To obtain the mechanical database of fire-resistant steels at high temperatures, tensile tests at high temperatures were conducted on steels of two kinds of thicknesses. The results showed that the thickness difference could not affect the mechanical properties at a high temperature.

Comparative Study for Long Span Beams built up with Sub-marine High Strength Structural Steels at High Temperature using Analytical Method (고강도 용접구조용 강재 적용 장스팬 보부재의 해석적 내화성능 비교 연구)

  • Kwon, In-Kyu
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2016.05a
    • /
    • pp.120-121
    • /
    • 2016
  • Recently, the building has been changed into high-rise and long span and this yields a development of high performance structural steels in construction market. According to this effect, the SM 520 and the SM 570 were developed and utilized into steel building industry. However, the study for fire resistance of them were not done actively. In this study, to know and comparative the fire resistance performance of long span beams built up with high strength structural steels an analytical method is going to applied using mechanical and thermal properties at high temperature.

  • PDF

Evaluation of Structural Stability of Fire Resistant Steel Produced by Thermo-Mechanical Control Process at High Temperature (TMCP 내화강재의 고온 내력 평가 연구)

  • Kwon, In-Kyu
    • Fire Science and Engineering
    • /
    • v.27 no.6
    • /
    • pp.21-25
    • /
    • 2013
  • Fire resistance steel, grading 490 MPa, had developed by using Thermo-mechanical control process (TMCP) and it has better performance at welding, seismic resistance than those of the ordinary structural steel, But the fire resistance performance is required to verify against the ordinary fire resistance, FR 490. Therefore this study was done to make database of mechanical properties at high temperature and to evaluate the structural stability at high temperature in terms of materials and structural member such as H-section from that of FR 490. The result of this study was that the structural stability of TMCP was lower than that of ordinary FR 490 at the range up about $700^{\circ}C$.

A Study on the Oxygen Index of Interior Wallpapers at Elevated Temperature (실내 내장 벽지의 고온산소지수에 대한 연구)

  • Oh, Kyu-Hyung;Lee, Sung-Eun;Kim, Hwang-Jin
    • Fire Science and Engineering
    • /
    • v.22 no.2
    • /
    • pp.57-62
    • /
    • 2008
  • Most of all the Korean home use a wallpaper as a decoration and finishing of interior. One of the fire spread factor in a house is a combustion of wall paper. There were some research concerning oxygen index in a ambient temperature. The purpose of this study is to investigate the difference of oxygen index of a wallpaper between ambient and high temperature and a effect on the fire spreading. Based on the result, the difference of oxygen index between ambient temperature and high temperature showed $5{\sim}8%$. Difference of 0.1% of oxygen index show big differences in combustion length of sample. Therefore, it was found that the decrease of oxygen index at elevated temperature is a important factor in fire spread.