• Title/Summary/Keyword: Short Columns

Search Result 196, Processing Time 0.022 seconds

Structural Behavior of Reinforced Concrete Short Columns by Pseudo-Dynamic Test (유사동적실험을 이용한 철근콘크리트 단주실험에 관한 연구)

  • Min, Kyung-Min;Kim, Yong-In;Lee, Kang-Seok
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2008.11a
    • /
    • pp.73-76
    • /
    • 2008

  • According to the survey of earthquake disaster, low-rise reinforced concrete building larger by the extent of damage and because of the underlying distribution of reinforced concrete structures more, it is very likely to be disasters. The purpose of this study is to discuss how strength and stiffness of each system in low-rise reinforced concrete buildings consisted of extremely brittle, shear and flexural failure lateral-load resisting systems have influence on seismic capacities of the overall system. Generally, if shear failure members including extremely brittle failure members are failed during an earthquake, the lateral-load resisting seismic capacities of RC buildings are lower rapidly, and if the seismic capacities of shear failure members were higher than that of flexural failure members, failures of shear failure members have influence on failures of the overall system. The result of this paper will provide pseudo-dynamic test of carried out to estimate the possibility of proposals.

  • PDF

Bond Behavior of Thin-Walled Rectangular Profiled Steel Sheet Concrete Short Columns (절곡된 단면을 갖는 얇은 판요소 콘크리트 충전 각형강관 기둥의 부착거동)

  • Yun, Hyun-Do;Park, Wan-Shin;Han, Byung-Chan
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.9 no.1
    • /
    • pp.233-241
    • /
    • 2005

  • The paper is presented experimental study results on bond stress between profiled steel and concrete in Profiled SPC(Profiled Steel Plate Concrete) rectangular steel tubes through an experimental program in which 13 pull-out specimens were tested. Advantages and class of composite members and current problems of construction work are noted, past research of PSSC is described. An experimental study is described and evaluated. The bond capacity is interrelated with slip at the steel concrete interface. The factors influencing the mechanism of bond stress transfer were the cross section shape, length/diameter, diameter/thickness and environmental parameters (temperature, moisture). The results of experimental program indicated that the force transfer could be characterized into two regions The first region was governed by bond with no relative slip between the profiled steel and concrete. The second region occurs after the chemical debonding. Bond stress transfer in this region was governed by frictional resistance between profiled steel and concrete and cross section shapes. The important factors influencing the magnitude of frictional resistance are the profiled steel shapes, length/diameter and environmental parameters. (temperature, moisture)

  • PDF KSCI

Study of the longitudinal reinforcement in reinforced concrete-filled steel tube short column subjected to axial loading

  • Alifujiang Xiamuxi;Caijian Liu;Alipujiang Jierula
    • Steel and Composite Structures
    • /
    • v.47 no.6
    • /
    • pp.709-728
    • /
    • 2023

  • Experimental and analytical studies were conducted to clarify the influencing mechanisms of the longitudinal reinforcement on performance of axially loaded Reinforced Concrete-Filled Steel Tube (R-CFST) short columns. The longitudinal reinforcement ratio was set as parameter, and 10 R-CFST specimens with five different ratios and three Concrete-Filled Steel Tube (CFST) specimens for comparison were prepared and tested. Based on the test results, the failure modes, load transfer responses, peak load, stiffness, yield to strength ratio, ductility, fracture toughness, composite efficiency and stress state of steel tube were theoretically analyzed. To further examine, analytical investigations were then performed, material model for concrete core was proposed and verified against the test, and thereafter 36 model specimens with four different wall-thickness of steel tube, coupling with nine reinforcement ratios, were simulated. Finally, considering the experimental and analytical results, the prediction equations for ultimate load bearing capacity of R-CFSTs were modified from the equations of CFSTs given in codes, and a new equation which embeds the effect of reinforcement was proposed, and equations were validated against experimental data. The results indicate that longitudinal reinforcement significantly impacts the behavior of R-CFST as steel tube does; the proposed analytical model is effective and reasonable; proper ratios of longitudinal reinforcement enable the R-CFSTs obtain better balance between the performance and the construction cost, and the range for the proper ratios is recommended between 1.0% and 3.0%, regardless of wall-thickness of steel tube; the proposed equation is recommended for more accurate and stable prediction of the strength of R-CFSTs.

  • https://doi.org/10.12989/scs.2023.47.6.709 인용

Earthquake performance investigation of R/C residential buildings in Turkey

  • Korkmaz, Kasim Armagan;Demir, Fuat;Yenice, Tugce
    • Computers and Concrete
    • /
    • v.15 no.6
    • /
    • pp.921-933
    • /
    • 2015

  • The aim of this study is to determine the earthquake performances of reinforced concrete (R/C) residential buildings in Turkey and to analyze the parameters that affect the performance. The performance of Turkish residential buildings, determined by their levels of damage, directly relates to their structural systems. Damage parameters observed from previous earthquakes define structural parameters selected to be used in the present study. Five different types of frame R/C buildings were modeled. For the analysis, the model buildings vary according to the number of stories, column sizes, and reinforcement and concrete strength parameters. The analyses consider gravity forces and earthquake loads through 1975 and 2007 Turkish design codes. In a total of 720 different R/C buildings were investigated for the analysis to obtain capacity curves. A performance evaluation was employed by considering the Turkish design code (TDC-2007). The current study ignores irregularities such as soft stories or short columns. The study's analysis considers a comparison of the parameters' influence on the structural performance of the model buildings.

  • https://doi.org/10.12989/cac.2015.15.6.921 인용 KSCI

Strength of Square Shaped CFT Stub Column Considering the Confining Effect of Concrete (콘크리트 구속효과를 고려한 정사각형 CFT단주의 강도)

  • Hwang, Won Sup;Kim, Dong Jo
    • Journal of Korean Society of Steel Construction
    • /
    • v.14 no.6
    • /
    • pp.813-822
    • /
    • 2002

  • The squash strength and design strength are smaller than the experimental strength of square shaped concrete-filled steel tubular columns in a short concentrically loaded column. This study presents an evaluation procedure accounting for the confining effect of concrete. For the purpose of evaluating a confining effect of concrete, the 3D finite element method was used. The influence of parameters, width-thickness ratios, strength of the concrete and the yield strength of the steel, were examined. The suggested evaluation procedure that assembled three parameters was compared with previous experimental results. Also, the tendency of the confining effect of concrete was examined in the three types of load application.

  • PDF KSCI

Strength of Axially Loaded Concrete-Filled Tubular Stub Column. (중심축하중을 받는 콘크리트충전 각형강관단주의 내력)

  • Kang, Chang-Hoon;Oh, Young-Suk;Moon, Tae-Sup
    • Journal of Korean Society of Steel Construction
    • /
    • v.13 no.3
    • /
    • pp.279-287
    • /
    • 2001

  • This paper presents an experimental and analytical study on the behavior of concrete-filled tubular stub columns concentrically loaded in compression to fail. Total eleven specimens were tested and test parameters are the depth-to-thickness ratios of steel tube and the ratio of concrete cylinder strength-to-yield stress of steel tube. Depth-to-thickness ratios of steel tube between 20.22

  • PDF

Vibration Control of Flexible Structures Using ER Dampers (ER 댐퍼를 이용한 유연구조물의 진동제어)

  • 최승복;이재홍
    • Journal of KSNVE
    • /
    • v.8 no.2
    • /
    • pp.313-323
    • /
    • 1998

  • This paper addresses a sliding mode control of vibration in a flexible structure using ER(electro-rheological) dampers. A clamped-clamped flexible structure system supported by two short columns is considered. Three ER dampers to be operated in shear mode are designed on the basis of Bingham model of the arabic gum-based ER fluid, and attached to the flexible beam structure. After deriving the governing equation of motion and associated boundary conditions, a sliding mode controller is formulated to effectively suppress the vibration of the beam structure caused by sinusoidal and random excitations. In the formulation of the controller, parameter variations such as natural frequency deviation are treated to take into account the robustness of control system. The effectiveness of the proposed control system is confirmed by both simulation and experimental results.

  • PDF

Comparisons of Elasto-Fiber and Fiber & Bernoulli-Euler reinforced concrete beam-column elements

  • Karaton, Muhammet
    • Structural Engineering and Mechanics
    • /
    • v.51 no.1
    • /
    • pp.89-110
    • /
    • 2014

  • In this study, two beam-column elements based on the Elasto-Fiber element theory for reinforced concrete (RC) element have been developed and compared with each other. The first element is based on Elasto Fiber Approach (EFA) was initially developed for steel structures and this theory was applied for RC element in there and the second element is called as Fiber & Bernoulli-Euler element approach (FBEA). In this element, Cubic Hermitian polynomials are used for obtaining stiffness matrix. The beams or columns element in both approaches are divided into a sub-element called the segment for obtaining element stiffness matrix. The internal freedoms of this segment are dynamically condensed to the external freedoms at the ends of the element by using a dynamic substructure technique. Thus, nonlinear dynamic analysis of high RC building can be obtained within short times. In addition to, external loads of the segment are assumed to be distributed along to element. Therefore, damages can be taken account of along to element and redistributions of the loading for solutions. Bossak-${\alpha}$ integration with predicted-corrected method is used for the nonlinear seismic analysis of RC frames. For numerical application, seismic damage analyses for a 4-story frame and an 8-story RC frame with soft-story are obtained to comparisons of RC element according to both approaches. Damages evaluation and propagation in the frame elements are studied and response quantities from obtained both approaches are investigated in the detail.

  • https://doi.org/10.12989/sem.2014.51.1.089 인용 KSCI

Numerical simulation of concrete confined by transverse reinforcement

  • Song, Zhenhuan;Lu, Yong
    • Computers and Concrete
    • /
    • v.8 no.1
    • /
    • pp.23-41
    • /
    • 2011

  • The behaviour of concrete confined by transverse reinforcement is a classical topic. Numerous studies have been conducted to establish the stress-strain relationships for concrete under various confining reinforcement arrangements. Many empirical and semi-empirical formulas exist. Simplified analytical models have also been proposed to evaluate the increase in the strength and ductility of confined concrete. However, relatively few studies have been conducted to utilise advanced computational models for a realistic simulation of the behaviour of concrete confined by transverse reinforcement. As a matter of fact, high fidelity simulations using the latest numerical solvers in conjunction with advanced material constitutive models can be a powerful means to investigating the mechanisms underlying the confining effects of different reinforcement schemes. This paper presents a study on the use of high fidelity finite element models for the investigation of the behaviour of concrete confined by stirrups, as well as the interpretation of the numerical results. The development of the models is described in detail, and the essential modelling considerations are discussed. The models are then validated by simulating representative experimental studies on short columns with different confining reinforcement schemes. The development and distribution of the confining stress and the subsequent increase in the axial strength are examined. The models are shown to be capable of reproducing the behaviour of the confined concrete realistically, paving a way for systematic parametric studies and investigation into complicated confinement, load combination, and dynamic loading situations.

  • https://doi.org/10.12989/cac.2011.8.1.023 인용 KSCI

Optical Properties of CIGS Films as Deposition Conditions of Mo Back Contact (MO 배면전극의 제조조건이 CIGS 박막의 광특성에 미치는 영향)

  • Kim, S.K.;Lee, J.L.;Kang, K.H.;Yoon, K.H.;Park, I.J.;Song, J.;Han, S.O.
    • Proceedings of the KIEE Conference
    • /
    • 2001.07c
    • /
    • pp.1518-1520
    • /
    • 2001

  • Bi-layer Mo films were deposited on sodalime glass substrates using DC magnetron sputtering. As the gas pressure and power density, the resistivity varied from $1.5{\times}10^{-5}$ to $4.97{\times}10^{-4}{\Omega}{\cdot}cm$. Furthermore, stress direction yielded compressive-to-tensile transition stress curves. The microstructure of the compressive stress films which had poor adhesion consists of tightly packed columns, but of the tensile-stressed films had less dense structure. Under all gas pressure conditions, Mo films exhibited distinctly increasing optical reflection with decreasing gas pressure. The expansion of (110) peak width with the gas pressure meant the worse crystalline growth. Also, The highest efficiency was 15.2% on 0.2 $cm^2$. The fill factor, open circuit voltage and short circuit current were 63 %, 570 mV and 42.6 mA/$cm^2$ respectively.

  • PDF