• 한국자동차공학회논문집
• /
• 제3권5호
• /
• pp.74-81
• /
• 1995

In this paper, the crushing tests of circular tubes under axial impact loading are conducted to investigate the energy absorption abilities. A cross head with 18kg launched by the compressed air collides against circular tubes. Circular tubes used for this experiment are Al and CFRP laminates, which have 8 ply with $15^{\circ}$ and $45^{\circ}$. The absorbed energy unit mass and volume of the CFRP specimen with $15^{\circ}$ are higher than those of aluminum specimen. CFRP specimen having small stacking angle have better energy absorption abilities than that of large stacking angle.

• 한국자동차공학회논문집
• /
• 제5권3호
• /
• pp.1-14
• /
• 1997

In this paper, collapse test of thin-walled structural member widely used for automobiles is carried out under static compression load to observe the effects of cross- sectional shape and material on the energy absorbing capacity in the viewpoint of cras- hworthiness. Specimens tested consist of two sorts(Aluminium, CFRP) and configur- ations(Circular, Square) with variation in thickness. Also, comparisons of Al circular and square specimens are made to find the influence of difference in shape on the energy absorbing capability according as the thickness of specimen varies.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1995년도 추계학술대회 논문집
• /
• pp.650-654
• /
• 1995

In this study, in order to measure energy-absorbing charactistics in collapse test of CFRP thin-walled laminates and interpretate the cause of decreasing age when collapse test is carried out under the environments of high temperatures and hygrothermals, the moisture absorbing behavior according to the variety of orientation angel is observed and collapse characteristics is compared with the influence of high temperatures and hygrothermals. Especially, we supposed to clearly understand reationship between collapse characteristics in proportion to the variety of orientation angel and moisture absorbing. The value of the maximum loading, mean loading,rate of energy absorption energy per unit volume and mass in CFRP thin-walled laminates on the high temperatures and hygrothermals is measured lower than under no moisture absorbing. The maximum collapse loading in dynamic impact test is taken measurement lower than in static collapse test regarding compared with collapse characteristics conformity with the variety of the CFRP circular laminates in high temperatures and hygrothermals. But the absorbed energy per unit mass and volume is almost same and the biggest amount of energy is shown in the CFRP circular laminates with orientation angel of 15 .deg.. Therefore, in the case of use to CFRP circular laminates with axisymmetric mode, CFRP thin-walled structal members with orientation angel of 10 .deg. , 15 . deg. are generally useful.

• 한국안전학회지
• /
• 제11권3호
• /
• pp.33-43
• /
• 1996

In this paper, collapse test of thin-walled structures, which are widely used in the vehicle members is carried out to observe the dependence of cross-sectional forms and materials on the absorbed energy in the viewpoint of crashworthiness. Also, specimens consist of two kinds (Al, CFRP) with various thickness. Comparisons of circular specimens are made to find characteristics of the different specimens on the absorption ability according to specimen thickness and materials.

• 한국정밀공학회지
• /
• 제20권10호
• /
• pp.177-182
• /
• 2003

The front-end side members of automobiles absorb most of the energy in a case of front-end collision. The front-end side members are required to have a high stiffness together with easiness to collapse sequentially to absorb more impact energy. The axial static collapse test (5mm/min) was conducted by using UTM for form different types of members which have different cross section shapes; single hat, single cap, double cap, and double hat. The single hat shaped section member has the typical standard section, which the double hat shape section has a symmetry in the center to have more stiffness. As a result of the test, the energy absorbing characteristic was analyzed for different section shapes. It turned out that the change of section shape influence the absorbing energy, the mean collapse load and the maximum collapse load, and the relation between the change of section shape and the collapse mode.

• 대한기계학회논문집A
• /
• 제38권9호
• /
• pp.959-965
• /
• 2014

본 연구에서는 Al/CFRP 혼성 구조부재가 승용차용 사이드부재에 사용될 것을 상정하여 Al/CFRP 혼성 구조부재의 단면형상의 변화, 최외각층의 변화가 압궤 특성에 어떠한 영향을 미치는가를 실험적으로 고찰하여 수송기계의 경량화를 위한 사이드부재로 사용될 수 있는 설계 데이터를 얻고자 하였다. 실험결과 다음과 같은 결론을 얻었다. 최외층각이 $0^{\circ}$로 적층된 원형 Al/CFRP 혼성 충격 흡수부재가 사각 Al/CFRP 혼성 충격 흡수부재 보다 52,9%, 모자형 Al/CFRP 혼성 충격 흡수부재 보다 49.93% 높게 나타났으며, 최외층각이 $90^{\circ}$로 적층된 경우 원형 Al/CFRP 혼성 충격 흡수부재 사각 Al/CFRP 혼성 충격 흡수부재 보다 50.49%, 모자형 Al/CFRP 혼성 충격 흡수부재 보다 49.2% 높게 나타났다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2003년도 춘계학술대회 논문집
• /
• pp.1549-1552
• /
• 2003

The front-end side members of automobiles absorb most of the energy in a front-end collision. The front-end side members are required to have a high stiffness together with easiness to collapse sequentially to absorb more impact energy. The axial static collapse test (5mm/mim) was conducted by using UTM with respect to the single hat shaped section members which are the standard section shape of the spot welded section members, to the single cap shaped section members, to the double cap shaped section members and to the double hat shaped section members whose section shape are changed in order to give more stiffness. As a result of test, the energy absorbing characteristic was analyzed for different section shapes. That is, it was analyzed that the change of section shape influenced the absorbing energy, the mean collapse load and the maximum collapse load, and that the relation between the change of section shape and the collapse mode.

• 한국자동차공학회논문집
• /
• 제9권6호
• /
• pp.195-200
• /
• 2001

Composites have wide applications in aerospace vehicles and automobiles because of the inherent flexibility in their design for improved material properties. Composite tribes in particular, are potential candidates for their use as energy absorbing elements in crashworthiness applications due to their high specific energy absorbing capacity and the stroke efficiency. Their failure mechanism however is highly complicated and rather difficult to analyze. This includes fracture in fibres, in the matrix and in the fibre-matrix interface in tension, compression and shear. The purpose of this study is to investigate the energy absorption characteristics of CFRP(Carbon Fiber Reinforced Plastics) tubes on static and impact tests. Static compression tests have been carried out using the static testing machine and impact tests have been carried out using the vertical crushing testing machine. Interlaminar number affect the energy absorption capability of CFRP tubes. Also, theoretical and experimental have the same value.

• 대한기계학회논문집A
• /
• 제25권7호
• /
• pp.1131-1138
• /
• 2001

This paper concerns the crashworthiness of the widely used vehicle structure, the spot welded hat and double hat shaped section members, which are excellent on the point of the energy absorbing capacity and low production cost. The target of this paper is to analyze the energy absorption capacity of the structure against the front-end collision, and to obtain useful information for designing stage. Changing the spot weld pitches on the flanges, the hat and double hat shaped section members were tested on the axial collapse loads in impact velocities of 4.72m/sec, 6.54m/sec, 7.19m/sec and 7.27m/sec. To efficiently review the collapse characteristics of these sections, the simulation have been carried out using explicit FEM package, LS-DYNA3D. The solutions are compared with results from the impact collapse experiments.