• Title/Summary/Keyword: steel structure

Search Result 4,067, Processing Time 0.028 seconds

Bond Stress of the Bar Removed Rust with Concrete (전식녹을 제거한 철근과 콘크리트의 부착응력에 관한 실험적 연구)

  • Choi, Hyo-Seok;Lee, Joo-Il;Ryu, Soo-Hyun;Yu, Ho-Hyun;Kim, Jin-Mu
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.5 no.1
    • /
    • pp.188-194
    • /
    • 2001
  • A reinforced concrete structure is complex structure that works as one body with bonding role of steel bar and concrete. The bonding action between steel bar and concrete makes possible the compound structure. The transmission of mutual strength of the steel bar with concrete in structure is determined by the bonding characteristic of steel bar and concrete surface. But the efficiency of bonding characteristic of steel bar is Questionable by the corrosion cause by the delay construction term, the wrong management, etc. So this study investigate bonding characteristic of reinforced concrete using pull-out test method which steel bar removed rust and the principal variables of this study are concrete compression strength and the degree of corrosion. The result showed that bonding strength tend to increase when removed rust of steel bar whereas it tend to decrease when not removed rust.

  • PDF

Simplified robustness assessment of steel framed structures under fire-induced column failure

  • Jiang, Binhui;Li, Guo-Qiang;Yam, Michael C.H.
    • Steel and Composite Structures
    • /
    • v.35 no.2
    • /
    • pp.199-213
    • /
    • 2020
  • This paper proposes a Global-Local Analysis Method (GLAM) to assess the progressive collapse of steel framed structures under fire-induced column failure. GLAM obtains the overall structural response by combining dynamic analysis of the heated column (local) with static analysis of the overall structure (global). Test results of two steel frames which explicitly consider the dynamic effect during fire-induced column failure were employed to validate the proposed GLAM. Results show that GLAM gives reasonable predictions to the test frames in terms of both whether to collapse and the displacement verse temperature curves. Besides, several case studies of a two-dimensional (2D) steel frame and a three-dimensional (3D) steel frame with concrete slabs were conducted by using GLAM. Results show that GLAM gives the same collapse predictions to the studied cases with nonlinear dynamic analysis of the whole structure model. Compared with nonlinear dynamic analysis of the whole structure model, GLAM saves approximately 70% and 99% CPU time for the cases of 2D and 3D steel frame, respectively. Results also show that the load level of a structure has notable effects on the restraint condition of a heated column in the structure.

Experimental Study on the Machenical Properties of Composite Beam Composed End Reinforced Concrete and Center Steel (RC-S 복합보의 역학적 특성에 관한 실험적 연구)

  • Kim, Cheol Hwan;Chae, Won Tak
    • Journal of Korean Society of Steel Construction
    • /
    • v.14 no.5 s.60
    • /
    • pp.675-682
    • /
    • 2002
  • The beam of composite structure composed of the RC structure in the end part and steel structure in the central palt were investigated during cyclic loading, in order to evaluate strength, stiffness, and deformational capacity. The parameters used in this study include the amount of reinforced steel bar between the steel beam and RC structure and the existence of the sticking plate. Test results showed that all specimens had stabilized hysteresis loops. Likewise, the specimens with sticking plate had higher load-carrying capacity compared with the one without it. In addition, the stiffness of the composite structure was higher than the steel structure. All specimens also showed good rotational capacity.

Design Optimization of Blast Resistant CFRP-steel Composite Structure Based on Reliability Analysis (신뢰성 해석에 의한 내폭 CFRP-steel 복합구조의 최적화 설계)

  • Kim, Jung Joong;Noh, Hyuk-Chun
    • Journal of the Korean Society for Advanced Composite Structures
    • /
    • v.3 no.4
    • /
    • pp.10-16
    • /
    • 2012
  • This study presents the effectiveness of a composite structure at improving blast resistance. The proposed composite structure consists of carbon fiber reinforced polymer (CFRP) and steel layers. While CFRP layer is used for blast energy reflection due to its high strength, steel layer is used for blast energy absorption due to its high ductility. A dynamic model is used to simulate the elastoplastic behavior of the proposed composite structure subject to blast load. Considering the magnitude variations of a blast event, the probability of failure of each layer is evaluated using reliability analysis. By assigning design probability of failure of each layer in the composite structure, the thickness of layers is optimized. A case study for the design of CFRP-steel composite structure subjected to an uncertain blast event is also presented.

Comparative Study of Design Methods for Manufacturing of Steel Structure (철구조물의 설계방법에 대한 비교 연구)

  • Kim, Dong-Kwon;Choi, Jae-Seung;Hwang, Suk-Hwan
    • Proceedings of the KSME Conference
    • /
    • 2000.11a
    • /
    • pp.357-362
    • /
    • 2000
  • Allowable stress design(ASD) method has been widely used to design steel structures such as boiler and heat recovery steam generator(HRSG) of power plant. However, many researchers are recently intrested in road and resistance factor design(LRFD) method which may take the place of ASD. In this work, the weight calculation of steel structure was compared when ASD and LRFD were applied respectively. For the calculation of weight of steel structure, computer program was developed and applied to obtain beam weight. Using this program and GTSTRUDL, structural design program, weight of steel structure is calculated. As a result of weight calculation, maximum 5.4% of weight reduction is achieved among examples of this study by applying LRFD comparing with the result of ASD, and those results quite dependent on the applied load and member classification.

  • PDF

GFRP retrofitting effect on the dynamic characteristics of model steel structure

  • Tuhta, Sertac
    • Steel and Composite Structures
    • /
    • v.28 no.2
    • /
    • pp.223-231
    • /
    • 2018
  • Nowadays, there are a great number of various structures that have been retrofitted by using different FRP Composites. Due to this, more researches need to be conducted to know more the characteristics of these structures, not only that but also a comparison among them before and after the retrofitting is needed. In this research, a model steel structure is tested using a bench-scale earthquake simulator on the shake table, using recorded micro tremor data, in order to get the dynamic behaviors. Columns of the model steel structure are then retrofitted by using GFRP composite, and then tested on the Quanser shake table by using the recorded micro tremor data. At this stage, it is needed to evaluate the dynamic behaviors of the retrofitted model steel structure. Various types of methods of OMA, such as EFDD, SSI, etc. are used to take action in the ambient responses. Having a purpose to learn more about the effects of GFRP composite, experimental model analysis of both types (retrofitted and no-retrofitted models) is conducted to evaluate their dynamic behaviors. There is a provision of ambient excitation to the shake table by using recorded micro tremor ambient vibration data on ground level. Furthermore, the Enhanced Frequency Domain Decomposition is used through output-only modal identification. At the end of this study, moderate correlation is obtained between mode shapes, periods and damping ratios. The aim of this research is to show and determine the effects of GFRP Composite implementation on structural responses of the model steel structure, in terms of changing its dynamical behaviors. The frequencies for model steel structure and the retrofitted model steel structure are shown to be 33.916% in average difference. Finally, it is shown that, in order to evaluate the period and rigidity of retrofitted structures, OMA might be used.

A Study on a Development of Hybrid(Magnesium & Steel) Structure for Application of Cockpit Module (Cockpit Module용 Hybrid Structure개발에 관한 연구)

  • 박병구;이정환;김영삼;한성수
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.10 no.6
    • /
    • pp.166-170
    • /
    • 2002
  • A hybrid structure composed of magnesium and steel is Instrument Panel structure used for the basement of cockpit module components. For that reason, A hybrid structure has to be designed for satisfying components assembly design facility and styling. There are various models of If like steel structure assembly, however having been applied normally, but magnesium structure assembly selected far saving weight down. This paper introduces a hybrid structure having advantages between steel and magnesium structure and presents a CAE technical solution based on a development project. furthermore, it provides desired direction of the future development is suggested.

A Study on the Design Elements for Steel-Framed School Buildings (철골조학교(鐵骨組學校)의 설계요소(設計要素)에 관한 연구(硏究))

  • Lee, Jae-Hoon;Hwang, Jun-Geun
    • Journal of the Korean Institute of Educational Facilities
    • /
    • v.11 no.1
    • /
    • pp.47-57
    • /
    • 2004
  • The Architects' design process is subjective and mysterious'. If we can reveal this process, it will be very helpful to proceed similar design projects. In the aspect of steel production, Korea is a strong country, but in the aspect of steel usage, Korea does not show its impacts as compared with other countries'. Even though steel has many merits in design as well as in structure, in Korea we have not applied it as design elements. In this situation, the demand of steel in school buildings is increasing, but steel also is used only on the basis of the structural and material meaning. So this thesis tries to find design elements of steel structure buildings, which can be applied in school buildings, through the analysis of existing steel structure buildings and the characteristics of steel.

Shaking Table Test of Steel Cylindrical Liquid Storage Tank Considering the Roof Characteristics

  • Bae, Doobyong;Park, Jang Ho
    • International journal of steel structures
    • /
    • v.18 no.4
    • /
    • pp.1167-1176
    • /
    • 2018
  • Steel cylindrical tanks are widely used for the storage of hazardous substances of which leakage must be prevented under any circumstances. However, the dynamic response of the steel cylindrical liquid storage tank depends sensitively on the fluid-structure interaction and the vibration of the tank structure and necessitates clarification for the safety of the tank structure. This paper presents the results of shaking table tests performed to examine the dynamic behavior of a scaled cylindrical steel tank model considering the presence or not of fixed roof and added mass at the top of the tank for various fluid levels. The test results confirm the occurrence of both beam-type and oval-type vibration modes and show that the larger content of liquid inside the container amplified the acceleration along the height of the cylindrical tank. The oval-type vibration modes are seen to be more dominant in case of large water-to-structure mass ratio.

A Study on Measurement for Earth Resistance of Steel Structure (철탑접지저항 측정에 관한 연구)

  • 박석탁;김시영
    • 전기의세계
    • /
    • v.22 no.6
    • /
    • pp.33-51
    • /
    • 1973
  • To lower the earth resistance shall be one of the most effective method for the prevention of lightening damage on power transmission line. In this report, in order to investigate various characteristic necessary to lowering the earth resistance, the following experiments have been made at 154KV U1San-PoHang T/L, 154KV YoSu-SoonChun T/L and so on. 1. Measurement of Earth specific resistance, 2. Efficiency of Earthing of concrete foundation for steel structure., 3. Efficiency of Earthing with counter poise., 4. Compound impulse test with foundation of steel structure and counter poise. With the above investigate a guidance have been prepared for the effective work-performance of steel structure.

  • PDF