• Title, Summary, Keyword: bending collapse

Search Result 124, Processing Time 0.028 seconds

A Study on the Bending Collapse at the Open Cross-Section Members with Experiment and Analysis (열린 단면 부재의 굽힘 붕괴 실험 및 해석에 관한 연구)

  • 이승철;강신유
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.21 no.4
    • /
    • pp.132-139
    • /
    • 2004
  • The open section members have been used as the members of vehicle such as automotives, airplanes and trains. When vehicles are crashed, these members have absorption of the energy and it is necessary for retainment of the survival space, and as the result, the prediction for the displacement of members in this case of the crash of vehicles is very important. The displacements of members in this case of the crash of automotives show combined aspect of both axial collapse and bending collapse. In the rollover accident when bending collapse happen, the collapse of each members is progressed by the plastic hinge which made from bending moment, and therefore the research for the behavior of members under bending moment after collapse is necessary to determine the internal energy which the members can absorb and the deformed shapes of the members on the step of design. In this paper, the characteristics of bending collapse at the members of the open cross-section were studied with experiment and numerical analysis. We made a comparative studied of the result of the experiment, and changed the axis according to the parallel-axis theorem.

Experimental Study on The Bending Collapse Characteristics of Al Rectangular Tubes (알루미늄 사각관의 굽힘붕괴특성에 관한 실험적 고찰)

  • 강신유;김창수;정태은
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.265-272
    • /
    • 1997
  • In this paper the bending collapse characteristics of 60 series Al rectangular tubes were studied with a pure bending collapse test rig which could apply the pure bending moment, there occured three kinds of bending collapse modes - local buckling, delayed buckling, tensile failure - depending on the b/t(width/thickness) ratio and material properties. Experiment results are compared with the results of finite element method.

  • PDF

Center Pillar Design for High Bending Collapse Performance (굽힘 붕괴 성능 향상을 위한 센터 필라 설계)

  • Kang, Sungjong;Park, Myeongjae
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.21 no.4
    • /
    • pp.128-134
    • /
    • 2013
  • High bending collapse performance (maximum resistance force and mean resistance force) of body center pillar is an important design target for vehicle safety against side impact. In this study, effect of the upper section shape and the thickness of outer reinforcement on bending collapse performance was investigated for the center pillar of a large passenger car. First, through bending collapse analyses using simple models with uniform section, an optimized center pillar upper section was chosen. Next, bending collapse performance for various models of the actual center pillar with changing the thickness of outer reinforcement were analyzed. The finally designed model showed distinctive enhancement in bending collapse performance nearly without weight increase.

The characteristics of bending collapse of aluminum/GFRP hybrid tube (알루미늄/GFRP 혼성튜브의 굽힘붕괴 특성)

  • 송민철;이정주
    • Proceedings of the Korean Society For Composite Materials Conference
    • /
    • /
    • pp.84-87
    • /
    • 2000
  • Square tubes used for vehicle structure components have an important role on keeping its stiffness and preserving occupant safety in vehicle collision and rollover in which it experience axial collapse, bending collapse or both. Bending collapse, which absorbs kinetic energy of the impact and retains a survival space for the occupant, is a dominant failure mode in oblique collision and rollover. Thus, in this paper, the bending collapse characteristics such as the maximum bending moment and energy absorption capacity of the square tube replaced by light-weight material were evaluated and presented. The bending test of cantilever tubes which were fabricated with aluminum, GFRP and aluminum/ GFRP hybrid by co-curing process was performed. Then the maximum bending moment and the energy absorption capacity from the moment-angle curve were evaluated. Based on the test results, it was found that aluminum/ GFRP hybrid tube can show better specific energy absorption capacity compared to the pure aluminum or GFRP tube and can convert unstable collapse mode which may occur in pure GFRP tube to stable collapse mode like a aluminum tube in which plastic hinge is developed.

  • PDF

A Study on the Local Buckling Collapse Behavior of an Aluminum Square Tube Beam under a Bending Load (굽힘하중을 받는 알루미늄 사각관 보의 국부적 좌굴붕괴 거동에 관한 연구)

  • Lee, Sung-Hyuk;Choi, Nak-Sam
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.27 no.12
    • /
    • pp.2011-2018
    • /
    • 2003
  • To analyze the bending collapse behavior of an aluminum square tube beam under a bending load, a finite element simulation for the four-point bending test has been performed. Using an aluminum tube beam specimen partly inserted with two steel bars, the local buckling deformation near the center of the tube beam was induced. The maximum bending load and the bending collapse behavior obtained from the numerical simulation were in good agreement with experimental results. Using a combination of the four-point bending test and its finite element simulation, analysis of the local buckling and the accompanied bending collapse behavior of aluminum tube beam could be quantitative accomplished.

Experimental Study on The Bending Collapse Characteristics of Aluminum Rectangular Tubes (알루미늄 사각관의 굽힘붕괴특성에 관한 실험적 고찰)

  • Kim, Chang-Soo;Chung, Tae-Eun;Kang, Shin-You
    • Transactions of Materials Processing
    • /
    • v.7 no.1
    • /
    • pp.49-58
    • /
    • 1998
  • In this paper the bending collapse characteristics of 6XXX series aluminum rectangular tubes were studied with a pure bending collapse test rig which could apply the pure bending moment without imposing additional shear and tensile forces. Under the pure bending moment, there occured three kinds of bending collapse modes-local buckling delayed buckling and tensile failure-depending on the a, b, t (depth width thickness) and material properties. Experimental results are compared with the results of finite element method and other methods.

  • PDF

Viscoplastic response and collapse of 316L stainless steel tubes under cyclic bending

  • Chang, Kao-Hua;Hsu, Chien-Min;Sheu, Shane-Rong;Pan, Wen-Fung
    • Steel and Composite Structures
    • /
    • v.5 no.5
    • /
    • pp.359-374
    • /
    • 2005
  • This paper presents the experimental and theoretical results of the viscoplastic response and collapse of 316L stainless steel tubes subjected to cyclic bending. The tube bending machine and curvature-ovalization measurement apparatus, which was designed by Pan et al. (1998), were used for conducting the cyclic curvature-controlled experiment. Three different curvature-rates were controlled to highlight the characteristic of viscoplastic response and collapse. Next, the endochronic theory and the principle of virtual work were used to simulate the viscoplastic response of 316L stainless steel tubes under cyclic bending. In addition, a proposed theoretical formulation (Lee and Pan 2001) was used to simulate the relationship between the controlled cyclic curvature and the number of cycles to produce buckling under cyclic bending at different curvature-rates (viscoplastic collapse). It has been shown that the theoretical simulations of the response and collapse correlate well with the experimental data.

Closed-Form Plastic Collapse Loads of Pipe Bends Under Combined Pressure and In-Plane Bending (압력과 모멘트의 복합하중을 받는 곡관의 소성 붕괴하중 예측식 개발)

  • Oh Chang-Sik;Kim Yun-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.30 no.8
    • /
    • pp.1008-1015
    • /
    • 2006
  • Based on three-dimensional (3-D) FE limit analyses, this paper provides plastic limit, collapse and instability load solutions for pipe bends under combined pressure and in-plane bending. The plastic limit loads are determined from FE limit analyses based on elastic-perfectly plastic materials using the small geometry change option, and the FE limit analyses using the large geometry change option provide plastic collapse loads (using the twice-elastic-slope method) and instability loads. For the bending mode, both closing bending and opening bending are considered, and a wide range of parameters related to the bend geometry is considered. Based on the FE results, closed-form approximations of plastic limit and collapse load solutions for pipe bends under combined pressure and bending are proposed.

Rationally modeling collapse due to bending and external pressure in pipelines

  • Nogueira, Andre C.
    • Earthquakes and Structures
    • /
    • v.3 no.3_4
    • /
    • pp.473-494
    • /
    • 2012
  • The capacity of pipelines to resist collapse under external pressure and bending moment is a major aspect of deepwater pipeline design. Existing design codes present interaction equations that quantify pipeline capacities under such loadings, although reasonably accurate, are based on empirical data fitting of the bending strain, and assumed simplistic interaction with external pressure collapse. The rational model for collapse of deepwater pipelines, which are relatively thick with a diameter-to-thickness ratio less than 40, provides a unique theoretical basis since it is derived from first principles such as force equilibrium and compatibility equations. This paper presents the rational model methodology and compares predicted results and recently published full scale experimental data on the subject. Predictive capabilities of the rational model are shown to be excellent. The methodology is extended for the problem of pipeline collapse under point load, longitudinal bending and external pressure. Due to its rational derivation and excellent prediction capabilities, it is recommended that design codes adopt the rational model methodology.

A Study on the Specific Equation of Bending Collapse for Extruded Aluminum Members (알루미늄 압출부재의 굽힘붕괴 특성식 산출에 관한 연구)

  • Kang, Shin-Yoo;Jang, Hye-Jeong
    • Journal of Industrial Technology
    • /
    • v.20 no.B
    • /
    • pp.131-138
    • /
    • 2000
  • In this paper, we would like to develop the bending collapse specific equation of aluminum members which are usually used in light-weight vehicle or electromobiles. The result of the developed equation are compared with that of test and finite element methods as the moment-rotational angle curves. Three types of aluminum members are tested with the pure bending collapse test rig. PAM-CRASH and ABAQUS program are used for finite element analysis. As the result the developed bending collapse governing equation is accurate in estimating the yield moment and the maximum moment. Especially, in the case of the local buckling and the delayed buckling, the developed equation is better effective than F.E.M.

  • PDF